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* Swapping a single global interrupt handler for a herd
@ 2019-01-17 14:34 Chris Wilson
  2019-01-17 14:34 ` [PATCH 01/23] drm/i915: Make all GPU resets atomic Chris Wilson
                   ` (27 more replies)
  0 siblings, 28 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx


_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* [PATCH 01/23] drm/i915: Make all GPU resets atomic
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 14:34 ` [PATCH 02/23] drm/i915/guc: Disable global reset Chris Wilson
                   ` (26 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

In preparation for the next few commits, make resetting the GPU atomic.
Currently, we have prepared gen6+ for atomic resetting of individual
engines, but now there is a requirement to perform the whole device
level reset (just the register poking) from inside an atomic context.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_reset.c             | 50 ++++++++++---------
 .../gpu/drm/i915/selftests/mock_gem_device.c  |  4 +-
 2 files changed, 29 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index 342d9ee42601..b9d0ea70361c 100644
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -144,14 +144,14 @@ static int i915_do_reset(struct drm_i915_private *i915,
 
 	/* Assert reset for at least 20 usec, and wait for acknowledgement. */
 	pci_write_config_byte(pdev, I915_GDRST, GRDOM_RESET_ENABLE);
-	usleep_range(50, 200);
-	err = wait_for(i915_in_reset(pdev), 500);
+	udelay(50);
+	err = wait_for_atomic(i915_in_reset(pdev), 50);
 
 	/* Clear the reset request. */
 	pci_write_config_byte(pdev, I915_GDRST, 0);
-	usleep_range(50, 200);
+	udelay(50);
 	if (!err)
-		err = wait_for(!i915_in_reset(pdev), 500);
+		err = wait_for_atomic(!i915_in_reset(pdev), 50);
 
 	return err;
 }
@@ -171,7 +171,7 @@ static int g33_do_reset(struct drm_i915_private *i915,
 	struct pci_dev *pdev = i915->drm.pdev;
 
 	pci_write_config_byte(pdev, I915_GDRST, GRDOM_RESET_ENABLE);
-	return wait_for(g4x_reset_complete(pdev), 500);
+	return wait_for_atomic(g4x_reset_complete(pdev), 50);
 }
 
 static int g4x_do_reset(struct drm_i915_private *dev_priv,
@@ -182,13 +182,13 @@ static int g4x_do_reset(struct drm_i915_private *dev_priv,
 	int ret;
 
 	/* WaVcpClkGateDisableForMediaReset:ctg,elk */
-	I915_WRITE(VDECCLK_GATE_D,
-		   I915_READ(VDECCLK_GATE_D) | VCP_UNIT_CLOCK_GATE_DISABLE);
-	POSTING_READ(VDECCLK_GATE_D);
+	I915_WRITE_FW(VDECCLK_GATE_D,
+		      I915_READ(VDECCLK_GATE_D) | VCP_UNIT_CLOCK_GATE_DISABLE);
+	POSTING_READ_FW(VDECCLK_GATE_D);
 
 	pci_write_config_byte(pdev, I915_GDRST,
 			      GRDOM_MEDIA | GRDOM_RESET_ENABLE);
-	ret =  wait_for(g4x_reset_complete(pdev), 500);
+	ret =  wait_for_atomic(g4x_reset_complete(pdev), 50);
 	if (ret) {
 		DRM_DEBUG_DRIVER("Wait for media reset failed\n");
 		goto out;
@@ -196,7 +196,7 @@ static int g4x_do_reset(struct drm_i915_private *dev_priv,
 
 	pci_write_config_byte(pdev, I915_GDRST,
 			      GRDOM_RENDER | GRDOM_RESET_ENABLE);
-	ret =  wait_for(g4x_reset_complete(pdev), 500);
+	ret =  wait_for_atomic(g4x_reset_complete(pdev), 50);
 	if (ret) {
 		DRM_DEBUG_DRIVER("Wait for render reset failed\n");
 		goto out;
@@ -205,9 +205,9 @@ static int g4x_do_reset(struct drm_i915_private *dev_priv,
 out:
 	pci_write_config_byte(pdev, I915_GDRST, 0);
 
-	I915_WRITE(VDECCLK_GATE_D,
-		   I915_READ(VDECCLK_GATE_D) & ~VCP_UNIT_CLOCK_GATE_DISABLE);
-	POSTING_READ(VDECCLK_GATE_D);
+	I915_WRITE_FW(VDECCLK_GATE_D,
+		      I915_READ(VDECCLK_GATE_D) & ~VCP_UNIT_CLOCK_GATE_DISABLE);
+	POSTING_READ_FW(VDECCLK_GATE_D);
 
 	return ret;
 }
@@ -218,27 +218,29 @@ static int ironlake_do_reset(struct drm_i915_private *dev_priv,
 {
 	int ret;
 
-	I915_WRITE(ILK_GDSR, ILK_GRDOM_RENDER | ILK_GRDOM_RESET_ENABLE);
-	ret = intel_wait_for_register(dev_priv,
-				      ILK_GDSR, ILK_GRDOM_RESET_ENABLE, 0,
-				      500);
+	I915_WRITE_FW(ILK_GDSR, ILK_GRDOM_RENDER | ILK_GRDOM_RESET_ENABLE);
+	ret = __intel_wait_for_register_fw(dev_priv, ILK_GDSR,
+					   ILK_GRDOM_RESET_ENABLE, 0,
+					   5000, 0,
+					   NULL);
 	if (ret) {
 		DRM_DEBUG_DRIVER("Wait for render reset failed\n");
 		goto out;
 	}
 
-	I915_WRITE(ILK_GDSR, ILK_GRDOM_MEDIA | ILK_GRDOM_RESET_ENABLE);
-	ret = intel_wait_for_register(dev_priv,
-				      ILK_GDSR, ILK_GRDOM_RESET_ENABLE, 0,
-				      500);
+	I915_WRITE_FW(ILK_GDSR, ILK_GRDOM_MEDIA | ILK_GRDOM_RESET_ENABLE);
+	ret = __intel_wait_for_register_fw(dev_priv, ILK_GDSR,
+					   ILK_GRDOM_RESET_ENABLE, 0,
+					   5000, 0,
+					   NULL);
 	if (ret) {
 		DRM_DEBUG_DRIVER("Wait for media reset failed\n");
 		goto out;
 	}
 
 out:
-	I915_WRITE(ILK_GDSR, 0);
-	POSTING_READ(ILK_GDSR);
+	I915_WRITE_FW(ILK_GDSR, 0);
+	POSTING_READ_FW(ILK_GDSR);
 	return ret;
 }
 
@@ -572,7 +574,9 @@ int intel_gpu_reset(struct drm_i915_private *i915, unsigned int engine_mask)
 		ret = -ENODEV;
 		if (reset) {
 			GEM_TRACE("engine_mask=%x\n", engine_mask);
+			preempt_disable();
 			ret = reset(i915, engine_mask, retry);
+			preempt_enable();
 		}
 		if (ret != -ETIMEDOUT || engine_mask != ALL_ENGINES)
 			break;
diff --git a/drivers/gpu/drm/i915/selftests/mock_gem_device.c b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
index 3cda66292e76..888c6978bc54 100644
--- a/drivers/gpu/drm/i915/selftests/mock_gem_device.c
+++ b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
@@ -58,8 +58,8 @@ static void mock_device_release(struct drm_device *dev)
 	i915_gem_contexts_lost(i915);
 	mutex_unlock(&i915->drm.struct_mutex);
 
-	cancel_delayed_work_sync(&i915->gt.retire_work);
-	cancel_delayed_work_sync(&i915->gt.idle_work);
+	drain_delayed_work(&i915->gt.retire_work);
+	drain_delayed_work(&i915->gt.idle_work);
 	i915_gem_drain_workqueue(i915);
 
 	mutex_lock(&i915->drm.struct_mutex);
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 02/23] drm/i915/guc: Disable global reset
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
  2019-01-17 14:34 ` [PATCH 01/23] drm/i915: Make all GPU resets atomic Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 14:34 ` [PATCH 03/23] drm/i915: Remove GPU reset dependence on struct_mutex Chris Wilson
                   ` (25 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

The guc (and huc) currently inexcruitably depend on struct_mutex for
device reinitialisation from inside the reset, and indeed taking any
mutex here is verboten (as we must be able to reset from underneath any
of our mutexes). That makes recovering the guc unviable without, for
example, reserving contiguous vma space and pages for it to use.

The plan to re-enable global reset for the GuC centers around reusing the
WOPM reserved space at the top of the aperture (that we know we can
populate a contiguous range large enough to dma xfer the fw image).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_reset.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index b9d0ea70361c..2961c21d9420 100644
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -590,6 +590,9 @@ int intel_gpu_reset(struct drm_i915_private *i915, unsigned int engine_mask)
 
 bool intel_has_gpu_reset(struct drm_i915_private *i915)
 {
+	if (USES_GUC(i915))
+		return false;
+
 	return intel_get_gpu_reset(i915);
 }
 
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 03/23] drm/i915: Remove GPU reset dependence on struct_mutex
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
  2019-01-17 14:34 ` [PATCH 01/23] drm/i915: Make all GPU resets atomic Chris Wilson
  2019-01-17 14:34 ` [PATCH 02/23] drm/i915/guc: Disable global reset Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 14:34 ` [PATCH 04/23] drm/i915/selftests: Trim struct_mutex duration for set-wedged selftest Chris Wilson
                   ` (24 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Now that the submission backends are controlled via their own spinlocks,
with a wave of a magic wand we can lift the struct_mutex requirement
around GPU reset. That is we allow the submission frontend (userspace)
to keep on submitting while we process the GPU reset as we can suspend
the backend independently.

The major change is around the backoff/handoff strategy for performing
the reset. With no mutex deadlock, we no longer have to coordinate with
any waiter, and just perform the reset immediately.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_debugfs.c           |  14 +-
 drivers/gpu/drm/i915/i915_drv.h               |   5 -
 drivers/gpu/drm/i915/i915_gem.c               |  18 +-
 drivers/gpu/drm/i915/i915_gem_fence_reg.h     |   1 -
 drivers/gpu/drm/i915/i915_gem_gtt.h           |   1 +
 drivers/gpu/drm/i915/i915_gpu_error.h         |  24 +-
 drivers/gpu/drm/i915/i915_request.c           |  47 ---
 drivers/gpu/drm/i915/i915_reset.c             | 397 ++++++++----------
 drivers/gpu/drm/i915/i915_reset.h             |   3 +
 drivers/gpu/drm/i915/intel_engine_cs.c        |   6 +-
 drivers/gpu/drm/i915/intel_guc_submission.c   |   5 +-
 drivers/gpu/drm/i915/intel_lrc.c              |  92 ++--
 drivers/gpu/drm/i915/intel_overlay.c          |   2 -
 drivers/gpu/drm/i915/intel_ringbuffer.c       |  91 ++--
 drivers/gpu/drm/i915/intel_ringbuffer.h       |  13 +-
 .../gpu/drm/i915/selftests/intel_hangcheck.c  |  57 +--
 .../drm/i915/selftests/intel_workarounds.c    |   3 -
 17 files changed, 317 insertions(+), 462 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 86152503331b..ba7f05b493ed 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1284,8 +1284,6 @@ static int i915_hangcheck_info(struct seq_file *m, void *unused)
 		seq_puts(m, "Wedged\n");
 	if (test_bit(I915_RESET_BACKOFF, &dev_priv->gpu_error.flags))
 		seq_puts(m, "Reset in progress: struct_mutex backoff\n");
-	if (test_bit(I915_RESET_HANDOFF, &dev_priv->gpu_error.flags))
-		seq_puts(m, "Reset in progress: reset handoff to waiter\n");
 	if (waitqueue_active(&dev_priv->gpu_error.wait_queue))
 		seq_puts(m, "Waiter holding struct mutex\n");
 	if (waitqueue_active(&dev_priv->gpu_error.reset_queue))
@@ -3907,11 +3905,6 @@ i915_wedged_set(void *data, u64 val)
 
 	i915_handle_error(i915, val, I915_ERROR_CAPTURE,
 			  "Manually set wedged engine mask = %llx", val);
-
-	wait_on_bit(&i915->gpu_error.flags,
-		    I915_RESET_HANDOFF,
-		    TASK_UNINTERRUPTIBLE);
-
 	return 0;
 }
 
@@ -4066,13 +4059,8 @@ i915_drop_caches_set(void *data, u64 val)
 		mutex_unlock(&i915->drm.struct_mutex);
 	}
 
-	if (val & DROP_RESET_ACTIVE &&
-	    i915_terminally_wedged(&i915->gpu_error)) {
+	if (val & DROP_RESET_ACTIVE && i915_terminally_wedged(&i915->gpu_error))
 		i915_handle_error(i915, ALL_ENGINES, 0, NULL);
-		wait_on_bit(&i915->gpu_error.flags,
-			    I915_RESET_HANDOFF,
-			    TASK_UNINTERRUPTIBLE);
-	}
 
 	fs_reclaim_acquire(GFP_KERNEL);
 	if (val & DROP_BOUND)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 310d9e1e1620..94680b15bed0 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3001,11 +3001,6 @@ static inline bool i915_reset_backoff(struct i915_gpu_error *error)
 	return unlikely(test_bit(I915_RESET_BACKOFF, &error->flags));
 }
 
-static inline bool i915_reset_handoff(struct i915_gpu_error *error)
-{
-	return unlikely(test_bit(I915_RESET_HANDOFF, &error->flags));
-}
-
 static inline bool i915_terminally_wedged(struct i915_gpu_error *error)
 {
 	return unlikely(test_bit(I915_WEDGED, &error->flags));
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index b359390ba22c..d20b42386c3c 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -657,11 +657,6 @@ i915_gem_object_wait(struct drm_i915_gem_object *obj,
 		     struct intel_rps_client *rps_client)
 {
 	might_sleep();
-#if IS_ENABLED(CONFIG_LOCKDEP)
-	GEM_BUG_ON(debug_locks &&
-		   !!lockdep_is_held(&obj->base.dev->struct_mutex) !=
-		   !!(flags & I915_WAIT_LOCKED));
-#endif
 	GEM_BUG_ON(timeout < 0);
 
 	timeout = i915_gem_object_wait_reservation(obj->resv,
@@ -4493,8 +4488,6 @@ void i915_gem_sanitize(struct drm_i915_private *i915)
 
 	GEM_TRACE("\n");
 
-	mutex_lock(&i915->drm.struct_mutex);
-
 	wakeref = intel_runtime_pm_get(i915);
 	intel_uncore_forcewake_get(i915, FORCEWAKE_ALL);
 
@@ -4520,6 +4513,7 @@ void i915_gem_sanitize(struct drm_i915_private *i915)
 	intel_uncore_forcewake_put(i915, FORCEWAKE_ALL);
 	intel_runtime_pm_put(i915, wakeref);
 
+	mutex_lock(&i915->drm.struct_mutex);
 	i915_gem_contexts_lost(i915);
 	mutex_unlock(&i915->drm.struct_mutex);
 }
@@ -4534,6 +4528,8 @@ int i915_gem_suspend(struct drm_i915_private *i915)
 	wakeref = intel_runtime_pm_get(i915);
 	intel_suspend_gt_powersave(i915);
 
+	flush_workqueue(i915->wq);
+
 	mutex_lock(&i915->drm.struct_mutex);
 
 	/*
@@ -4563,11 +4559,9 @@ int i915_gem_suspend(struct drm_i915_private *i915)
 	i915_retire_requests(i915); /* ensure we flush after wedging */
 
 	mutex_unlock(&i915->drm.struct_mutex);
+	i915_reset_flush(i915);
 
-	intel_uc_suspend(i915);
-
-	cancel_delayed_work_sync(&i915->gpu_error.hangcheck_work);
-	cancel_delayed_work_sync(&i915->gt.retire_work);
+	drain_delayed_work(&i915->gt.retire_work);
 
 	/*
 	 * As the idle_work is rearming if it detects a race, play safe and
@@ -4575,6 +4569,8 @@ int i915_gem_suspend(struct drm_i915_private *i915)
 	 */
 	drain_delayed_work(&i915->gt.idle_work);
 
+	intel_uc_suspend(i915);
+
 	/*
 	 * Assert that we successfully flushed all the work and
 	 * reset the GPU back to its idle, low power state.
diff --git a/drivers/gpu/drm/i915/i915_gem_fence_reg.h b/drivers/gpu/drm/i915/i915_gem_fence_reg.h
index 99a31ded4dfd..09dcaf14121b 100644
--- a/drivers/gpu/drm/i915/i915_gem_fence_reg.h
+++ b/drivers/gpu/drm/i915/i915_gem_fence_reg.h
@@ -50,4 +50,3 @@ struct drm_i915_fence_reg {
 };
 
 #endif
-
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 9229b03d629b..a0039ea97cdc 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -39,6 +39,7 @@
 #include <linux/pagevec.h>
 
 #include "i915_request.h"
+#include "i915_reset.h"
 #include "i915_selftest.h"
 #include "i915_timeline.h"
 
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.h b/drivers/gpu/drm/i915/i915_gpu_error.h
index 604291f7762d..733723e1ea03 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.h
+++ b/drivers/gpu/drm/i915/i915_gpu_error.h
@@ -197,6 +197,8 @@ struct i915_gpu_state {
 	struct scatterlist *sgl, *fit;
 };
 
+struct i915_gpu_restart;
+
 struct i915_gpu_error {
 	/* For hangcheck timer */
 #define DRM_I915_HANGCHECK_PERIOD 1500 /* in ms */
@@ -247,15 +249,6 @@ struct i915_gpu_error {
 	 * i915_mutex_lock_interruptible()?). I915_RESET_BACKOFF serves a
 	 * secondary role in preventing two concurrent global reset attempts.
 	 *
-	 * #I915_RESET_HANDOFF - To perform the actual GPU reset, we need the
-	 * struct_mutex. We try to acquire the struct_mutex in the reset worker,
-	 * but it may be held by some long running waiter (that we cannot
-	 * interrupt without causing trouble). Once we are ready to do the GPU
-	 * reset, we set the I915_RESET_HANDOFF bit and wakeup any waiters. If
-	 * they already hold the struct_mutex and want to participate they can
-	 * inspect the bit and do the reset directly, otherwise the worker
-	 * waits for the struct_mutex.
-	 *
 	 * #I915_RESET_ENGINE[num_engines] - Since the driver doesn't need to
 	 * acquire the struct_mutex to reset an engine, we need an explicit
 	 * flag to prevent two concurrent reset attempts in the same engine.
@@ -269,20 +262,13 @@ struct i915_gpu_error {
 	 */
 	unsigned long flags;
 #define I915_RESET_BACKOFF	0
-#define I915_RESET_HANDOFF	1
-#define I915_RESET_MODESET	2
-#define I915_RESET_ENGINE	3
+#define I915_RESET_MODESET	1
+#define I915_RESET_ENGINE	2
 #define I915_WEDGED		(BITS_PER_LONG - 1)
 
 	/** Number of times an engine has been reset */
 	u32 reset_engine_count[I915_NUM_ENGINES];
 
-	/** Set of stalled engines with guilty requests, in the current reset */
-	u32 stalled_mask;
-
-	/** Reason for the current *global* reset */
-	const char *reason;
-
 	struct mutex wedge_mutex; /* serialises wedging/unwedging */
 
 	/**
@@ -299,6 +285,8 @@ struct i915_gpu_error {
 
 	/* For missed irq/seqno simulation. */
 	unsigned long test_irq_rings;
+
+	struct i915_gpu_restart *restart;
 };
 
 struct drm_i915_error_state_buf {
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 5403d4e2cee0..fb723ed2f574 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -1076,18 +1076,6 @@ static bool __i915_spin_request(const struct i915_request *rq,
 	return false;
 }
 
-static bool __i915_wait_request_check_and_reset(struct i915_request *request)
-{
-	struct i915_gpu_error *error = &request->i915->gpu_error;
-
-	if (likely(!i915_reset_handoff(error)))
-		return false;
-
-	__set_current_state(TASK_RUNNING);
-	i915_reset(request->i915, error->stalled_mask, error->reason);
-	return true;
-}
-
 /**
  * i915_request_wait - wait until execution of request has finished
  * @rq: the request to wait upon
@@ -1113,17 +1101,10 @@ long i915_request_wait(struct i915_request *rq,
 {
 	const int state = flags & I915_WAIT_INTERRUPTIBLE ?
 		TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE;
-	wait_queue_head_t *errq = &rq->i915->gpu_error.wait_queue;
-	DEFINE_WAIT_FUNC(reset, default_wake_function);
 	DEFINE_WAIT_FUNC(exec, default_wake_function);
 	struct intel_wait wait;
 
 	might_sleep();
-#if IS_ENABLED(CONFIG_LOCKDEP)
-	GEM_BUG_ON(debug_locks &&
-		   !!lockdep_is_held(&rq->i915->drm.struct_mutex) !=
-		   !!(flags & I915_WAIT_LOCKED));
-#endif
 	GEM_BUG_ON(timeout < 0);
 
 	if (i915_request_completed(rq))
@@ -1133,11 +1114,7 @@ long i915_request_wait(struct i915_request *rq,
 		return -ETIME;
 
 	trace_i915_request_wait_begin(rq, flags);
-
 	add_wait_queue(&rq->execute, &exec);
-	if (flags & I915_WAIT_LOCKED)
-		add_wait_queue(errq, &reset);
-
 	intel_wait_init(&wait);
 	if (flags & I915_WAIT_PRIORITY)
 		i915_schedule_bump_priority(rq, I915_PRIORITY_WAIT);
@@ -1148,10 +1125,6 @@ long i915_request_wait(struct i915_request *rq,
 		if (intel_wait_update_request(&wait, rq))
 			break;
 
-		if (flags & I915_WAIT_LOCKED &&
-		    __i915_wait_request_check_and_reset(rq))
-			continue;
-
 		if (signal_pending_state(state, current)) {
 			timeout = -ERESTARTSYS;
 			goto complete;
@@ -1181,9 +1154,6 @@ long i915_request_wait(struct i915_request *rq,
 		 */
 		goto wakeup;
 
-	if (flags & I915_WAIT_LOCKED)
-		__i915_wait_request_check_and_reset(rq);
-
 	for (;;) {
 		if (signal_pending_state(state, current)) {
 			timeout = -ERESTARTSYS;
@@ -1207,21 +1177,6 @@ long i915_request_wait(struct i915_request *rq,
 		if (i915_request_completed(rq))
 			break;
 
-		/*
-		 * If the GPU is hung, and we hold the lock, reset the GPU
-		 * and then check for completion. On a full reset, the engine's
-		 * HW seqno will be advanced passed us and we are complete.
-		 * If we do a partial reset, we have to wait for the GPU to
-		 * resume and update the breadcrumb.
-		 *
-		 * If we don't hold the mutex, we can just wait for the worker
-		 * to come along and update the breadcrumb (either directly
-		 * itself, or indirectly by recovering the GPU).
-		 */
-		if (flags & I915_WAIT_LOCKED &&
-		    __i915_wait_request_check_and_reset(rq))
-			continue;
-
 		/* Only spin if we know the GPU is processing this request */
 		if (__i915_spin_request(rq, wait.seqno, state, 2))
 			break;
@@ -1235,8 +1190,6 @@ long i915_request_wait(struct i915_request *rq,
 	intel_engine_remove_wait(rq->engine, &wait);
 complete:
 	__set_current_state(TASK_RUNNING);
-	if (flags & I915_WAIT_LOCKED)
-		remove_wait_queue(errq, &reset);
 	remove_wait_queue(&rq->execute, &exec);
 	trace_i915_request_wait_end(rq);
 
diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index 2961c21d9420..064fc6da1512 100644
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -5,6 +5,7 @@
  */
 
 #include <linux/sched/mm.h>
+#include <linux/stop_machine.h>
 
 #include "i915_drv.h"
 #include "i915_gpu_error.h"
@@ -17,22 +18,23 @@ static void engine_skip_context(struct i915_request *rq)
 	struct intel_engine_cs *engine = rq->engine;
 	struct i915_gem_context *hung_ctx = rq->gem_context;
 	struct i915_timeline *timeline = rq->timeline;
-	unsigned long flags;
 
+	lockdep_assert_held(&engine->timeline.lock);
 	GEM_BUG_ON(timeline == &engine->timeline);
 
-	spin_lock_irqsave(&engine->timeline.lock, flags);
 	spin_lock(&timeline->lock);
 
-	list_for_each_entry_continue(rq, &engine->timeline.requests, link)
-		if (rq->gem_context == hung_ctx)
-			i915_request_skip(rq, -EIO);
+	if (rq->global_seqno) {
+		list_for_each_entry_continue(rq,
+					     &engine->timeline.requests, link)
+			if (rq->gem_context == hung_ctx)
+				i915_request_skip(rq, -EIO);
+	}
 
 	list_for_each_entry(rq, &timeline->requests, link)
 		i915_request_skip(rq, -EIO);
 
 	spin_unlock(&timeline->lock);
-	spin_unlock_irqrestore(&engine->timeline.lock, flags);
 }
 
 static void client_mark_guilty(struct drm_i915_file_private *file_priv,
@@ -59,7 +61,7 @@ static void client_mark_guilty(struct drm_i915_file_private *file_priv,
 	}
 }
 
-static void context_mark_guilty(struct i915_gem_context *ctx)
+static bool context_mark_guilty(struct i915_gem_context *ctx)
 {
 	unsigned int score;
 	bool banned, bannable;
@@ -72,7 +74,7 @@ static void context_mark_guilty(struct i915_gem_context *ctx)
 
 	/* Cool contexts don't accumulate client ban score */
 	if (!bannable)
-		return;
+		return false;
 
 	if (banned) {
 		DRM_DEBUG_DRIVER("context %s: guilty %d, score %u, banned\n",
@@ -83,6 +85,8 @@ static void context_mark_guilty(struct i915_gem_context *ctx)
 
 	if (!IS_ERR_OR_NULL(ctx->file_priv))
 		client_mark_guilty(ctx->file_priv, ctx);
+
+	return banned;
 }
 
 static void context_mark_innocent(struct i915_gem_context *ctx)
@@ -90,6 +94,21 @@ static void context_mark_innocent(struct i915_gem_context *ctx)
 	atomic_inc(&ctx->active_count);
 }
 
+void i915_reset_request(struct i915_request *rq, bool guilty)
+{
+	lockdep_assert_held(&rq->engine->timeline.lock);
+	GEM_BUG_ON(i915_request_completed(rq));
+
+	if (guilty) {
+		i915_request_skip(rq, -EIO);
+		if (context_mark_guilty(rq->gem_context))
+			engine_skip_context(rq);
+	} else {
+		dma_fence_set_error(&rq->fence, -EAGAIN);
+		context_mark_innocent(rq->gem_context);
+	}
+}
+
 static void gen3_stop_engine(struct intel_engine_cs *engine)
 {
 	struct drm_i915_private *dev_priv = engine->i915;
@@ -533,22 +552,6 @@ int intel_gpu_reset(struct drm_i915_private *i915, unsigned int engine_mask)
 	int retry;
 	int ret;
 
-	/*
-	 * We want to perform per-engine reset from atomic context (e.g.
-	 * softirq), which imposes the constraint that we cannot sleep.
-	 * However, experience suggests that spending a bit of time waiting
-	 * for a reset helps in various cases, so for a full-device reset
-	 * we apply the opposite rule and wait if we want to. As we should
-	 * always follow up a failed per-engine reset with a full device reset,
-	 * being a little faster, stricter and more error prone for the
-	 * atomic case seems an acceptable compromise.
-	 *
-	 * Unfortunately this leads to a bimodal routine, when the goal was
-	 * to have a single reset function that worked for resetting any
-	 * number of engines simultaneously.
-	 */
-	might_sleep_if(engine_mask == ALL_ENGINES);
-
 	/*
 	 * If the power well sleeps during the reset, the reset
 	 * request may be dropped and never completes (causing -EIO).
@@ -580,8 +583,6 @@ int intel_gpu_reset(struct drm_i915_private *i915, unsigned int engine_mask)
 		}
 		if (ret != -ETIMEDOUT || engine_mask != ALL_ENGINES)
 			break;
-
-		cond_resched();
 	}
 	intel_uncore_forcewake_put(i915, FORCEWAKE_ALL);
 
@@ -620,11 +621,8 @@ int intel_reset_guc(struct drm_i915_private *i915)
  * Ensure irq handler finishes, and not run again.
  * Also return the active request so that we only search for it once.
  */
-static struct i915_request *
-reset_prepare_engine(struct intel_engine_cs *engine)
+static void reset_prepare_engine(struct intel_engine_cs *engine)
 {
-	struct i915_request *rq;
-
 	/*
 	 * During the reset sequence, we must prevent the engine from
 	 * entering RC6. As the context state is undefined until we restart
@@ -633,162 +631,86 @@ reset_prepare_engine(struct intel_engine_cs *engine)
 	 * GPU state upon resume, i.e. fail to restart after a reset.
 	 */
 	intel_uncore_forcewake_get(engine->i915, FORCEWAKE_ALL);
-
-	rq = engine->reset.prepare(engine);
-	if (rq && rq->fence.error == -EIO)
-		rq = ERR_PTR(-EIO); /* Previous reset failed! */
-
-	return rq;
+	engine->reset.prepare(engine);
 }
 
-static int reset_prepare(struct drm_i915_private *i915)
+static void reset_prepare(struct drm_i915_private *i915)
 {
 	struct intel_engine_cs *engine;
-	struct i915_request *rq;
 	enum intel_engine_id id;
-	int err = 0;
 
-	for_each_engine(engine, i915, id) {
-		rq = reset_prepare_engine(engine);
-		if (IS_ERR(rq)) {
-			err = PTR_ERR(rq);
-			continue;
-		}
-
-		engine->hangcheck.active_request = rq;
-	}
+	for_each_engine(engine, i915, id)
+		reset_prepare_engine(engine);
 
-	i915_gem_revoke_fences(i915);
 	intel_uc_sanitize(i915);
-
-	return err;
 }
 
-/* Returns the request if it was guilty of the hang */
-static struct i915_request *
-reset_request(struct intel_engine_cs *engine,
-	      struct i915_request *rq,
-	      bool stalled)
+static int gt_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
 {
+	struct intel_engine_cs *engine;
+	enum intel_engine_id id;
+	int err;
+
 	/*
-	 * The guilty request will get skipped on a hung engine.
-	 *
-	 * Users of client default contexts do not rely on logical
-	 * state preserved between batches so it is safe to execute
-	 * queued requests following the hang. Non default contexts
-	 * rely on preserved state, so skipping a batch loses the
-	 * evolution of the state and it needs to be considered corrupted.
-	 * Executing more queued batches on top of corrupted state is
-	 * risky. But we take the risk by trying to advance through
-	 * the queued requests in order to make the client behaviour
-	 * more predictable around resets, by not throwing away random
-	 * amount of batches it has prepared for execution. Sophisticated
-	 * clients can use gem_reset_stats_ioctl and dma fence status
-	 * (exported via sync_file info ioctl on explicit fences) to observe
-	 * when it loses the context state and should rebuild accordingly.
-	 *
-	 * The context ban, and ultimately the client ban, mechanism are safety
-	 * valves if client submission ends up resulting in nothing more than
-	 * subsequent hangs.
+	 * Everything depends on having the GTT running, so we need to start
+	 * there.
 	 */
+	err = i915_ggtt_enable_hw(i915);
+	if (err)
+		return err;
 
-	if (i915_request_completed(rq)) {
-		GEM_TRACE("%s pardoned global=%d (fence %llx:%lld), current %d\n",
-			  engine->name, rq->global_seqno,
-			  rq->fence.context, rq->fence.seqno,
-			  intel_engine_get_seqno(engine));
-		stalled = false;
-	}
-
-	if (stalled) {
-		context_mark_guilty(rq->gem_context);
-		i915_request_skip(rq, -EIO);
+	for_each_engine(engine, i915, id)
+		intel_engine_reset(engine, stalled_mask & ENGINE_MASK(id));
 
-		/* If this context is now banned, skip all pending requests. */
-		if (i915_gem_context_is_banned(rq->gem_context))
-			engine_skip_context(rq);
-	} else {
-		/*
-		 * Since this is not the hung engine, it may have advanced
-		 * since the hang declaration. Double check by refinding
-		 * the active request at the time of the reset.
-		 */
-		rq = i915_gem_find_active_request(engine);
-		if (rq) {
-			unsigned long flags;
-
-			context_mark_innocent(rq->gem_context);
-			dma_fence_set_error(&rq->fence, -EAGAIN);
-
-			/* Rewind the engine to replay the incomplete rq */
-			spin_lock_irqsave(&engine->timeline.lock, flags);
-			rq = list_prev_entry(rq, link);
-			if (&rq->link == &engine->timeline.requests)
-				rq = NULL;
-			spin_unlock_irqrestore(&engine->timeline.lock, flags);
-		}
-	}
+	i915_gem_restore_fences(i915);
 
-	return rq;
+	return err;
 }
 
-static void reset_engine(struct intel_engine_cs *engine,
-			 struct i915_request *rq,
-			 bool stalled)
+static void reset_finish_engine(struct intel_engine_cs *engine)
 {
-	if (rq)
-		rq = reset_request(engine, rq, stalled);
-
-	/* Setup the CS to resume from the breadcrumb of the hung request */
-	engine->reset.reset(engine, rq);
+	engine->reset.finish(engine);
+	intel_uncore_forcewake_put(engine->i915, FORCEWAKE_ALL);
 }
 
-static void gt_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
+struct i915_gpu_restart {
+	struct work_struct work;
+	struct drm_i915_private *i915;
+};
+
+static void restart_work(struct work_struct *work)
 {
+	struct i915_gpu_restart *arg = container_of(work, typeof(*arg), work);
+	struct drm_i915_private *i915 = arg->i915;
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
+	intel_wakeref_t wakeref;
 
-	lockdep_assert_held(&i915->drm.struct_mutex);
+	wakeref = intel_runtime_pm_get(i915);
+	mutex_lock(&i915->drm.struct_mutex);
 
-	i915_retire_requests(i915);
+	smp_store_mb(i915->gpu_error.restart, NULL);
 
 	for_each_engine(engine, i915, id) {
-		struct intel_context *ce;
-
-		reset_engine(engine,
-			     engine->hangcheck.active_request,
-			     stalled_mask & ENGINE_MASK(id));
-		ce = fetch_and_zero(&engine->last_retired_context);
-		if (ce)
-			intel_context_unpin(ce);
+		struct i915_request *rq;
 
 		/*
 		 * Ostensibily, we always want a context loaded for powersaving,
 		 * so if the engine is idle after the reset, send a request
 		 * to load our scratch kernel_context.
-		 *
-		 * More mysteriously, if we leave the engine idle after a reset,
-		 * the next userspace batch may hang, with what appears to be
-		 * an incoherent read by the CS (presumably stale TLB). An
-		 * empty request appears sufficient to paper over the glitch.
 		 */
-		if (intel_engine_is_idle(engine)) {
-			struct i915_request *rq;
+		if (!intel_engine_is_idle(engine))
+			continue;
 
-			rq = i915_request_alloc(engine, i915->kernel_context);
-			if (!IS_ERR(rq))
-				i915_request_add(rq);
-		}
+		rq = i915_request_alloc(engine, i915->kernel_context);
+		if (!IS_ERR(rq))
+			i915_request_add(rq);
 	}
 
-	i915_gem_restore_fences(i915);
-}
-
-static void reset_finish_engine(struct intel_engine_cs *engine)
-{
-	engine->reset.finish(engine);
+	mutex_unlock(&i915->drm.struct_mutex);
+	intel_runtime_pm_put(i915, wakeref);
 
-	intel_uncore_forcewake_put(engine->i915, FORCEWAKE_ALL);
+	kfree(arg);
 }
 
 static void reset_finish(struct drm_i915_private *i915)
@@ -796,11 +718,30 @@ static void reset_finish(struct drm_i915_private *i915)
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
 
-	lockdep_assert_held(&i915->drm.struct_mutex);
-
-	for_each_engine(engine, i915, id) {
-		engine->hangcheck.active_request = NULL;
+	for_each_engine(engine, i915, id)
 		reset_finish_engine(engine);
+}
+
+static void reset_restart(struct drm_i915_private *i915)
+{
+	struct i915_gpu_restart *arg;
+
+	/*
+	 * Following the reset, ensure that we always reload context for
+	 * powersaving, and to correct engine->last_retired_context. Since
+	 * this requires us to submit a request, queue a worker to do that
+	 * task for us to evade any locking here.
+	 */
+	if (READ_ONCE(i915->gpu_error.restart))
+		return;
+
+	arg = kmalloc(sizeof(*arg), GFP_KERNEL);
+	if (arg) {
+		arg->i915 = i915;
+		INIT_WORK(&arg->work, restart_work);
+
+		WRITE_ONCE(i915->gpu_error.restart, arg);
+		queue_work(i915->wq, &arg->work);
 	}
 }
 
@@ -889,8 +830,6 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 	struct i915_timeline *tl;
 	bool ret = false;
 
-	lockdep_assert_held(&i915->drm.struct_mutex);
-
 	if (!test_bit(I915_WEDGED, &error->flags))
 		return true;
 
@@ -913,9 +852,9 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 	 */
 	list_for_each_entry(tl, &i915->gt.timelines, link) {
 		struct i915_request *rq;
+		long timeout;
 
-		rq = i915_gem_active_peek(&tl->last_request,
-					  &i915->drm.struct_mutex);
+		rq = i915_gem_active_get_unlocked(&tl->last_request);
 		if (!rq)
 			continue;
 
@@ -930,12 +869,12 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 		 * and when the seqno passes the fence, the signaler
 		 * then signals the fence waking us up).
 		 */
-		if (dma_fence_default_wait(&rq->fence, true,
-					   MAX_SCHEDULE_TIMEOUT) < 0)
+		timeout = dma_fence_default_wait(&rq->fence, true,
+						 MAX_SCHEDULE_TIMEOUT);
+		i915_request_put(rq);
+		if (timeout < 0)
 			goto unlock;
 	}
-	i915_retire_requests(i915);
-	GEM_BUG_ON(i915->gt.active_requests);
 
 	intel_engines_sanitize(i915, false);
 
@@ -949,7 +888,6 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 	 * context and do not require stop_machine().
 	 */
 	intel_engines_reset_default_submission(i915);
-	i915_gem_contexts_lost(i915);
 
 	GEM_TRACE("end\n");
 
@@ -962,6 +900,43 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 	return ret;
 }
 
+struct __i915_reset {
+	struct drm_i915_private *i915;
+	unsigned int stalled_mask;
+};
+
+static int __i915_reset__BKL(void *data)
+{
+	struct __i915_reset *arg = data;
+	int err;
+
+	err = intel_gpu_reset(arg->i915, ALL_ENGINES);
+	if (err)
+		return err;
+
+	return gt_reset(arg->i915, arg->stalled_mask);
+}
+
+#if 0
+#define __do_reset(fn, arg) stop_machine(fn, arg, NULL)
+#else
+#define __do_reset(fn, arg) fn(arg)
+#endif
+
+static int do_reset(struct drm_i915_private *i915, unsigned int stalled_mask)
+{
+	struct __i915_reset arg = { i915, stalled_mask };
+	int err, i;
+
+	err = __do_reset(__i915_reset__BKL, &arg);
+	for (i = 0; err && i < 3; i++) {
+		msleep(100);
+		err = __do_reset(__i915_reset__BKL, &arg);
+	}
+
+	return err;
+}
+
 /**
  * i915_reset - reset chip after a hang
  * @i915: #drm_i915_private to reset
@@ -987,31 +962,22 @@ void i915_reset(struct drm_i915_private *i915,
 {
 	struct i915_gpu_error *error = &i915->gpu_error;
 	int ret;
-	int i;
 
 	GEM_TRACE("flags=%lx\n", error->flags);
 
 	might_sleep();
-	lockdep_assert_held(&i915->drm.struct_mutex);
 	assert_rpm_wakelock_held(i915);
 	GEM_BUG_ON(!test_bit(I915_RESET_BACKOFF, &error->flags));
 
-	if (!test_bit(I915_RESET_HANDOFF, &error->flags))
-		return;
-
 	/* Clear any previous failed attempts at recovery. Time to try again. */
 	if (!i915_gem_unset_wedged(i915))
-		goto wakeup;
+		return;
 
 	if (reason)
 		dev_notice(i915->drm.dev, "Resetting chip for %s\n", reason);
 	error->reset_count++;
 
-	ret = reset_prepare(i915);
-	if (ret) {
-		dev_err(i915->drm.dev, "GPU recovery failed\n");
-		goto taint;
-	}
+	reset_prepare(i915);
 
 	if (!intel_has_gpu_reset(i915)) {
 		if (i915_modparams.reset)
@@ -1021,32 +987,11 @@ void i915_reset(struct drm_i915_private *i915,
 		goto error;
 	}
 
-	for (i = 0; i < 3; i++) {
-		ret = intel_gpu_reset(i915, ALL_ENGINES);
-		if (ret == 0)
-			break;
-
-		msleep(100);
-	}
-	if (ret) {
+	if (do_reset(i915, stalled_mask)) {
 		dev_err(i915->drm.dev, "Failed to reset chip\n");
 		goto taint;
 	}
 
-	/* Ok, now get things going again... */
-
-	/*
-	 * Everything depends on having the GTT running, so we need to start
-	 * there.
-	 */
-	ret = i915_ggtt_enable_hw(i915);
-	if (ret) {
-		DRM_ERROR("Failed to re-enable GGTT following reset (%d)\n",
-			  ret);
-		goto error;
-	}
-
-	gt_reset(i915, stalled_mask);
 	intel_overlay_reset(i915);
 
 	/*
@@ -1068,9 +1013,8 @@ void i915_reset(struct drm_i915_private *i915,
 
 finish:
 	reset_finish(i915);
-wakeup:
-	clear_bit(I915_RESET_HANDOFF, &error->flags);
-	wake_up_bit(&error->flags, I915_RESET_HANDOFF);
+	if (!i915_terminally_wedged(error))
+		reset_restart(i915);
 	return;
 
 taint:
@@ -1089,7 +1033,6 @@ void i915_reset(struct drm_i915_private *i915,
 	add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
 error:
 	i915_gem_set_wedged(i915);
-	i915_retire_requests(i915);
 	goto finish;
 }
 
@@ -1115,18 +1058,16 @@ static inline int intel_gt_reset_engine(struct drm_i915_private *i915,
 int i915_reset_engine(struct intel_engine_cs *engine, const char *msg)
 {
 	struct i915_gpu_error *error = &engine->i915->gpu_error;
-	struct i915_request *active_request;
 	int ret;
 
 	GEM_TRACE("%s flags=%lx\n", engine->name, error->flags);
 	GEM_BUG_ON(!test_bit(I915_RESET_ENGINE + engine->id, &error->flags));
 
-	active_request = reset_prepare_engine(engine);
-	if (IS_ERR_OR_NULL(active_request)) {
-		/* Either the previous reset failed, or we pardon the reset. */
-		ret = PTR_ERR(active_request);
-		goto out;
-	}
+	if (i915_seqno_passed(intel_engine_get_seqno(engine),
+			      intel_engine_last_submit(engine)))
+		return 0;
+
+	reset_prepare_engine(engine);
 
 	if (msg)
 		dev_notice(engine->i915->drm.dev,
@@ -1150,7 +1091,7 @@ int i915_reset_engine(struct intel_engine_cs *engine, const char *msg)
 	 * active request and can drop it, adjust head to skip the offending
 	 * request to resume executing remaining requests in the queue.
 	 */
-	reset_engine(engine, active_request, true);
+	intel_engine_reset(engine, true);
 
 	/*
 	 * The engine and its registers (and workarounds in case of render)
@@ -1187,30 +1128,7 @@ static void i915_reset_device(struct drm_i915_private *i915,
 	i915_wedge_on_timeout(&w, i915, 5 * HZ) {
 		intel_prepare_reset(i915);
 
-		error->reason = reason;
-		error->stalled_mask = engine_mask;
-
-		/* Signal that locked waiters should reset the GPU */
-		smp_mb__before_atomic();
-		set_bit(I915_RESET_HANDOFF, &error->flags);
-		wake_up_all(&error->wait_queue);
-
-		/*
-		 * Wait for anyone holding the lock to wakeup, without
-		 * blocking indefinitely on struct_mutex.
-		 */
-		do {
-			if (mutex_trylock(&i915->drm.struct_mutex)) {
-				i915_reset(i915, engine_mask, reason);
-				mutex_unlock(&i915->drm.struct_mutex);
-			}
-		} while (wait_on_bit_timeout(&error->flags,
-					     I915_RESET_HANDOFF,
-					     TASK_UNINTERRUPTIBLE,
-					     1));
-
-		error->stalled_mask = 0;
-		error->reason = NULL;
+		i915_reset(i915, engine_mask, reason);
 
 		intel_finish_reset(i915);
 	}
@@ -1366,6 +1284,25 @@ void i915_handle_error(struct drm_i915_private *i915,
 	intel_runtime_pm_put(i915, wakeref);
 }
 
+bool i915_reset_flush(struct drm_i915_private *i915)
+{
+	int err;
+
+	cancel_delayed_work_sync(&i915->gpu_error.hangcheck_work);
+
+	flush_workqueue(i915->wq);
+	GEM_BUG_ON(READ_ONCE(i915->gpu_error.restart));
+
+	mutex_lock(&i915->drm.struct_mutex);
+	err = i915_gem_wait_for_idle(i915,
+				     I915_WAIT_LOCKED |
+				     I915_WAIT_FOR_IDLE_BOOST,
+				     MAX_SCHEDULE_TIMEOUT);
+	mutex_unlock(&i915->drm.struct_mutex);
+
+	return !err;
+}
+
 static void i915_wedge_me(struct work_struct *work)
 {
 	struct i915_wedge_me *w = container_of(work, typeof(*w), work.work);
diff --git a/drivers/gpu/drm/i915/i915_reset.h b/drivers/gpu/drm/i915/i915_reset.h
index b6a519bde67d..f2d347f319df 100644
--- a/drivers/gpu/drm/i915/i915_reset.h
+++ b/drivers/gpu/drm/i915/i915_reset.h
@@ -29,6 +29,9 @@ void i915_reset(struct drm_i915_private *i915,
 int i915_reset_engine(struct intel_engine_cs *engine,
 		      const char *reason);
 
+void i915_reset_request(struct i915_request *rq, bool guilty);
+bool i915_reset_flush(struct drm_i915_private *i915);
+
 bool intel_has_gpu_reset(struct drm_i915_private *i915);
 bool intel_has_reset_engine(struct drm_i915_private *i915);
 
diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index c33de5c1ae66..e2f65c59d6e8 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -1074,10 +1074,8 @@ void intel_engines_sanitize(struct drm_i915_private *i915, bool force)
 	if (!reset_engines(i915) && !force)
 		return;
 
-	for_each_engine(engine, i915, id) {
-		if (engine->reset.reset)
-			engine->reset.reset(engine, NULL);
-	}
+	for_each_engine(engine, i915, id)
+		intel_engine_reset(engine, false);
 }
 
 /**
diff --git a/drivers/gpu/drm/i915/intel_guc_submission.c b/drivers/gpu/drm/i915/intel_guc_submission.c
index ab1c49b106f2..7217c7e3ee8d 100644
--- a/drivers/gpu/drm/i915/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/intel_guc_submission.c
@@ -834,8 +834,7 @@ static void guc_submission_tasklet(unsigned long data)
 	spin_unlock_irqrestore(&engine->timeline.lock, flags);
 }
 
-static struct i915_request *
-guc_reset_prepare(struct intel_engine_cs *engine)
+static void guc_reset_prepare(struct intel_engine_cs *engine)
 {
 	struct intel_engine_execlists * const execlists = &engine->execlists;
 
@@ -861,8 +860,6 @@ guc_reset_prepare(struct intel_engine_cs *engine)
 	 */
 	if (engine->i915->guc.preempt_wq)
 		flush_workqueue(engine->i915->guc.preempt_wq);
-
-	return i915_gem_find_active_request(engine);
 }
 
 /*
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index c0a42afaf177..7b56f2f17203 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -136,6 +136,7 @@
 #include <drm/i915_drm.h>
 #include "i915_drv.h"
 #include "i915_gem_render_state.h"
+#include "i915_reset.h"
 #include "i915_vgpu.h"
 #include "intel_lrc_reg.h"
 #include "intel_mocs.h"
@@ -264,7 +265,8 @@ static void unwind_wa_tail(struct i915_request *rq)
 	assert_ring_tail_valid(rq->ring, rq->tail);
 }
 
-static void __unwind_incomplete_requests(struct intel_engine_cs *engine)
+static struct i915_request *
+__unwind_incomplete_requests(struct intel_engine_cs *engine)
 {
 	struct i915_request *rq, *rn, *active = NULL;
 	struct list_head *uninitialized_var(pl);
@@ -305,6 +307,8 @@ static void __unwind_incomplete_requests(struct intel_engine_cs *engine)
 		list_move_tail(&active->sched.link,
 			       i915_sched_lookup_priolist(engine, prio));
 	}
+
+	return active;
 }
 
 void
@@ -1712,11 +1716,9 @@ static int gen8_init_common_ring(struct intel_engine_cs *engine)
 	return 0;
 }
 
-static struct i915_request *
-execlists_reset_prepare(struct intel_engine_cs *engine)
+static void execlists_reset_prepare(struct intel_engine_cs *engine)
 {
 	struct intel_engine_execlists * const execlists = &engine->execlists;
-	struct i915_request *request, *active;
 	unsigned long flags;
 
 	GEM_TRACE("%s: depth<-%d\n", engine->name,
@@ -1732,59 +1734,21 @@ execlists_reset_prepare(struct intel_engine_cs *engine)
 	 * prevents the race.
 	 */
 	__tasklet_disable_sync_once(&execlists->tasklet);
+	GEM_BUG_ON(!reset_in_progress(execlists));
 
+	/* And flush any current direct submission. */
 	spin_lock_irqsave(&engine->timeline.lock, flags);
-
-	/*
-	 * We want to flush the pending context switches, having disabled
-	 * the tasklet above, we can assume exclusive access to the execlists.
-	 * For this allows us to catch up with an inflight preemption event,
-	 * and avoid blaming an innocent request if the stall was due to the
-	 * preemption itself.
-	 */
-	process_csb(engine);
-
-	/*
-	 * The last active request can then be no later than the last request
-	 * now in ELSP[0]. So search backwards from there, so that if the GPU
-	 * has advanced beyond the last CSB update, it will be pardoned.
-	 */
-	active = NULL;
-	request = port_request(execlists->port);
-	if (request) {
-		/*
-		 * Prevent the breadcrumb from advancing before we decide
-		 * which request is currently active.
-		 */
-		intel_engine_stop_cs(engine);
-
-		list_for_each_entry_from_reverse(request,
-						 &engine->timeline.requests,
-						 link) {
-			if (__i915_request_completed(request,
-						     request->global_seqno))
-				break;
-
-			active = request;
-		}
-	}
-
+	process_csb(engine); /* drain preemption events */
 	spin_unlock_irqrestore(&engine->timeline.lock, flags);
-
-	return active;
 }
 
-static void execlists_reset(struct intel_engine_cs *engine,
-			    struct i915_request *request)
+static void execlists_reset(struct intel_engine_cs *engine, bool stalled)
 {
 	struct intel_engine_execlists * const execlists = &engine->execlists;
+	struct i915_request *rq;
 	unsigned long flags;
 	u32 *regs;
 
-	GEM_TRACE("%s request global=%d, current=%d\n",
-		  engine->name, request ? request->global_seqno : 0,
-		  intel_engine_get_seqno(engine));
-
 	spin_lock_irqsave(&engine->timeline.lock, flags);
 
 	/*
@@ -1799,12 +1763,18 @@ static void execlists_reset(struct intel_engine_cs *engine,
 	execlists_cancel_port_requests(execlists);
 
 	/* Push back any incomplete requests for replay after the reset. */
-	__unwind_incomplete_requests(engine);
+	rq = __unwind_incomplete_requests(engine);
 
 	/* Following the reset, we need to reload the CSB read/write pointers */
 	reset_csb_pointers(&engine->execlists);
 
-	spin_unlock_irqrestore(&engine->timeline.lock, flags);
+	GEM_TRACE("%s seqno=%d, current=%d, stalled? %s\n",
+		  engine->name,
+		  rq ? rq->global_seqno : 0,
+		  intel_engine_get_seqno(engine),
+		  yesno(stalled));
+	if (!rq)
+		goto out_unlock;
 
 	/*
 	 * If the request was innocent, we leave the request in the ELSP
@@ -1817,8 +1787,9 @@ static void execlists_reset(struct intel_engine_cs *engine,
 	 * and have to at least restore the RING register in the context
 	 * image back to the expected values to skip over the guilty request.
 	 */
-	if (!request || request->fence.error != -EIO)
-		return;
+	i915_reset_request(rq, stalled);
+	if (!stalled)
+		goto out_unlock;
 
 	/*
 	 * We want a simple context + ring to execute the breadcrumb update.
@@ -1828,25 +1799,23 @@ static void execlists_reset(struct intel_engine_cs *engine,
 	 * future request will be after userspace has had the opportunity
 	 * to recreate its own state.
 	 */
-	regs = request->hw_context->lrc_reg_state;
+	regs = rq->hw_context->lrc_reg_state;
 	if (engine->pinned_default_state) {
 		memcpy(regs, /* skip restoring the vanilla PPHWSP */
 		       engine->pinned_default_state + LRC_STATE_PN * PAGE_SIZE,
 		       engine->context_size - PAGE_SIZE);
 	}
-	execlists_init_reg_state(regs,
-				 request->gem_context, engine, request->ring);
+	execlists_init_reg_state(regs, rq->gem_context, engine, rq->ring);
 
 	/* Move the RING_HEAD onto the breadcrumb, past the hanging batch */
-	regs[CTX_RING_BUFFER_START + 1] = i915_ggtt_offset(request->ring->vma);
-
-	request->ring->head = intel_ring_wrap(request->ring, request->postfix);
-	regs[CTX_RING_HEAD + 1] = request->ring->head;
+	regs[CTX_RING_BUFFER_START + 1] = i915_ggtt_offset(rq->ring->vma);
 
-	intel_ring_update_space(request->ring);
+	rq->ring->head = intel_ring_wrap(rq->ring, rq->postfix);
+	regs[CTX_RING_HEAD + 1] = rq->ring->head;
+	intel_ring_update_space(rq->ring);
 
-	/* Reset WaIdleLiteRestore:bdw,skl as well */
-	unwind_wa_tail(request);
+out_unlock:
+	spin_unlock_irqrestore(&engine->timeline.lock, flags);
 }
 
 static void execlists_reset_finish(struct intel_engine_cs *engine)
@@ -1859,6 +1828,7 @@ static void execlists_reset_finish(struct intel_engine_cs *engine)
 	 * to sleep before we restart and reload a context.
 	 *
 	 */
+	GEM_BUG_ON(!reset_in_progress(execlists));
 	if (!RB_EMPTY_ROOT(&execlists->queue.rb_root))
 		execlists->tasklet.func(execlists->tasklet.data);
 
diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
index c81db81e4416..f68c7975006c 100644
--- a/drivers/gpu/drm/i915/intel_overlay.c
+++ b/drivers/gpu/drm/i915/intel_overlay.c
@@ -478,8 +478,6 @@ void intel_overlay_reset(struct drm_i915_private *dev_priv)
 	if (!overlay)
 		return;
 
-	intel_overlay_release_old_vid(overlay);
-
 	overlay->old_xscale = 0;
 	overlay->old_yscale = 0;
 	overlay->crtc = NULL;
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 26b7274a2d43..662907e1a286 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -33,6 +33,7 @@
 
 #include "i915_drv.h"
 #include "i915_gem_render_state.h"
+#include "i915_reset.h"
 #include "i915_trace.h"
 #include "intel_drv.h"
 #include "intel_workarounds.h"
@@ -707,52 +708,80 @@ static int init_ring_common(struct intel_engine_cs *engine)
 	return ret;
 }
 
-static struct i915_request *reset_prepare(struct intel_engine_cs *engine)
+static void reset_prepare(struct intel_engine_cs *engine)
 {
 	intel_engine_stop_cs(engine);
-	return i915_gem_find_active_request(engine);
 }
 
-static void skip_request(struct i915_request *rq)
+static void reset_ring(struct intel_engine_cs *engine, bool stalled)
 {
-	void *vaddr = rq->ring->vaddr;
+	struct i915_timeline *tl = &engine->timeline;
+	struct i915_request *pos, *rq;
+	unsigned long flags;
 	u32 head;
 
-	head = rq->infix;
-	if (rq->postfix < head) {
-		memset32(vaddr + head, MI_NOOP,
-			 (rq->ring->size - head) / sizeof(u32));
-		head = 0;
+	rq = NULL;
+	spin_lock_irqsave(&tl->lock, flags);
+	list_for_each_entry(pos, &tl->requests, link) {
+		if (!__i915_request_completed(pos, pos->global_seqno)) {
+			rq = pos;
+			break;
+		}
 	}
-	memset32(vaddr + head, MI_NOOP, (rq->postfix - head) / sizeof(u32));
-}
-
-static void reset_ring(struct intel_engine_cs *engine, struct i915_request *rq)
-{
-	GEM_TRACE("%s request global=%d, current=%d\n",
-		  engine->name, rq ? rq->global_seqno : 0,
-		  intel_engine_get_seqno(engine));
 
+	GEM_TRACE("%s seqno=%d, current=%d, stalled? %s\n",
+		  engine->name,
+		  rq ? rq->global_seqno : 0,
+		  intel_engine_get_seqno(engine),
+		  yesno(stalled));
 	/*
-	 * Try to restore the logical GPU state to match the continuation
-	 * of the request queue. If we skip the context/PD restore, then
-	 * the next request may try to execute assuming that its context
-	 * is valid and loaded on the GPU and so may try to access invalid
-	 * memory, prompting repeated GPU hangs.
+	 * The guilty request will get skipped on a hung engine.
 	 *
-	 * If the request was guilty, we still restore the logical state
-	 * in case the next request requires it (e.g. the aliasing ppgtt),
-	 * but skip over the hung batch.
+	 * Users of client default contexts do not rely on logical
+	 * state preserved between batches so it is safe to execute
+	 * queued requests following the hang. Non default contexts
+	 * rely on preserved state, so skipping a batch loses the
+	 * evolution of the state and it needs to be considered corrupted.
+	 * Executing more queued batches on top of corrupted state is
+	 * risky. But we take the risk by trying to advance through
+	 * the queued requests in order to make the client behaviour
+	 * more predictable around resets, by not throwing away random
+	 * amount of batches it has prepared for execution. Sophisticated
+	 * clients can use gem_reset_stats_ioctl and dma fence status
+	 * (exported via sync_file info ioctl on explicit fences) to observe
+	 * when it loses the context state and should rebuild accordingly.
 	 *
-	 * If the request was innocent, we try to replay the request with
-	 * the restored context.
+	 * The context ban, and ultimately the client ban, mechanism are safety
+	 * valves if client submission ends up resulting in nothing more than
+	 * subsequent hangs.
 	 */
+
 	if (rq) {
-		/* If the rq hung, jump to its breadcrumb and skip the batch */
-		rq->ring->head = intel_ring_wrap(rq->ring, rq->head);
-		if (rq->fence.error == -EIO)
-			skip_request(rq);
+		/*
+		 * Try to restore the logical GPU state to match the
+		 * continuation of the request queue. If we skip the
+		 * context/PD restore, then the next request may try to execute
+		 * assuming that its context is valid and loaded on the GPU and
+		 * so may try to access invalid memory, prompting repeated GPU
+		 * hangs.
+		 *
+		 * If the request was guilty, we still restore the logical
+		 * state in case the next request requires it (e.g. the
+		 * aliasing ppgtt), but skip over the hung batch.
+		 *
+		 * If the request was innocent, we try to replay the request
+		 * with the restored context.
+		 */
+		i915_reset_request(rq, stalled);
+
+		GEM_BUG_ON(rq->ring != engine->buffer);
+		head = rq->head;
+	} else {
+		head = engine->buffer->tail;
 	}
+	engine->buffer->head = intel_ring_wrap(engine->buffer, head);
+
+	spin_unlock_irqrestore(&tl->lock, flags);
 }
 
 static void reset_finish(struct intel_engine_cs *engine)
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 616f6bbb18ad..1adf9845710c 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -124,7 +124,6 @@ struct intel_engine_hangcheck {
 	unsigned long action_timestamp;
 	int deadlock;
 	struct intel_instdone instdone;
-	struct i915_request *active_request;
 	bool stalled:1;
 	bool wedged:1;
 };
@@ -445,9 +444,8 @@ struct intel_engine_cs {
 	int		(*init_hw)(struct intel_engine_cs *engine);
 
 	struct {
-		struct i915_request *(*prepare)(struct intel_engine_cs *engine);
-		void (*reset)(struct intel_engine_cs *engine,
-			      struct i915_request *rq);
+		void (*prepare)(struct intel_engine_cs *engine);
+		void (*reset)(struct intel_engine_cs *engine, bool stalled);
 		void (*finish)(struct intel_engine_cs *engine);
 	} reset;
 
@@ -1019,6 +1017,13 @@ gen8_emit_ggtt_write(u32 *cs, u32 value, u32 gtt_offset)
 	return cs;
 }
 
+static inline void intel_engine_reset(struct intel_engine_cs *engine,
+				      bool stalled)
+{
+	if (engine->reset.reset)
+		engine->reset.reset(engine, stalled);
+}
+
 void intel_engines_sanitize(struct drm_i915_private *i915, bool force);
 
 bool intel_engine_is_idle(struct intel_engine_cs *engine);
diff --git a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
index 12550b55c42f..67431355cd6e 100644
--- a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
+++ b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
@@ -363,9 +363,7 @@ static int igt_global_reset(void *arg)
 	/* Check that we can issue a global GPU reset */
 
 	igt_global_reset_lock(i915);
-	set_bit(I915_RESET_HANDOFF, &i915->gpu_error.flags);
 
-	mutex_lock(&i915->drm.struct_mutex);
 	reset_count = i915_reset_count(&i915->gpu_error);
 
 	i915_reset(i915, ALL_ENGINES, NULL);
@@ -374,9 +372,7 @@ static int igt_global_reset(void *arg)
 		pr_err("No GPU reset recorded!\n");
 		err = -EINVAL;
 	}
-	mutex_unlock(&i915->drm.struct_mutex);
 
-	GEM_BUG_ON(test_bit(I915_RESET_HANDOFF, &i915->gpu_error.flags));
 	igt_global_reset_unlock(i915);
 
 	if (i915_terminally_wedged(&i915->gpu_error))
@@ -399,9 +395,7 @@ static int igt_wedged_reset(void *arg)
 	i915_gem_set_wedged(i915);
 	GEM_BUG_ON(!i915_terminally_wedged(&i915->gpu_error));
 
-	set_bit(I915_RESET_HANDOFF, &i915->gpu_error.flags);
 	i915_reset(i915, ALL_ENGINES, NULL);
-	GEM_BUG_ON(test_bit(I915_RESET_HANDOFF, &i915->gpu_error.flags));
 
 	intel_runtime_pm_put(i915, wakeref);
 	mutex_unlock(&i915->drm.struct_mutex);
@@ -511,7 +505,7 @@ static int __igt_reset_engine(struct drm_i915_private *i915, bool active)
 				break;
 			}
 
-			if (!wait_for_idle(engine)) {
+			if (!i915_reset_flush(i915)) {
 				struct drm_printer p =
 					drm_info_printer(i915->drm.dev);
 
@@ -903,20 +897,13 @@ static int igt_reset_engines(void *arg)
 	return 0;
 }
 
-static u32 fake_hangcheck(struct i915_request *rq, u32 mask)
+static u32 fake_hangcheck(struct drm_i915_private *i915, u32 mask)
 {
-	struct i915_gpu_error *error = &rq->i915->gpu_error;
-	u32 reset_count = i915_reset_count(error);
-
-	error->stalled_mask = mask;
-
-	/* set_bit() must be after we have setup the backchannel (mask) */
-	smp_mb__before_atomic();
-	set_bit(I915_RESET_HANDOFF, &error->flags);
+	u32 count = i915_reset_count(&i915->gpu_error);
 
-	wake_up_all(&error->wait_queue);
+	i915_reset(i915, mask, NULL);
 
-	return reset_count;
+	return count;
 }
 
 static int igt_reset_wait(void *arg)
@@ -962,7 +949,7 @@ static int igt_reset_wait(void *arg)
 		goto out_rq;
 	}
 
-	reset_count = fake_hangcheck(rq, ALL_ENGINES);
+	reset_count = fake_hangcheck(i915, ALL_ENGINES);
 
 	timeout = i915_request_wait(rq, I915_WAIT_LOCKED, 10);
 	if (timeout < 0) {
@@ -972,7 +959,6 @@ static int igt_reset_wait(void *arg)
 		goto out_rq;
 	}
 
-	GEM_BUG_ON(test_bit(I915_RESET_HANDOFF, &i915->gpu_error.flags));
 	if (i915_reset_count(&i915->gpu_error) == reset_count) {
 		pr_err("No GPU reset recorded!\n");
 		err = -EINVAL;
@@ -1162,7 +1148,7 @@ static int __igt_reset_evict_vma(struct drm_i915_private *i915,
 	}
 
 out_reset:
-	fake_hangcheck(rq, intel_engine_flag(rq->engine));
+	fake_hangcheck(rq->i915, intel_engine_flag(rq->engine));
 
 	if (tsk) {
 		struct igt_wedge_me w;
@@ -1341,12 +1327,7 @@ static int igt_reset_queue(void *arg)
 				goto fini;
 			}
 
-			reset_count = fake_hangcheck(prev, ENGINE_MASK(id));
-
-			i915_reset(i915, ENGINE_MASK(id), NULL);
-
-			GEM_BUG_ON(test_bit(I915_RESET_HANDOFF,
-					    &i915->gpu_error.flags));
+			reset_count = fake_hangcheck(i915, ENGINE_MASK(id));
 
 			if (prev->fence.error != -EIO) {
 				pr_err("GPU reset not recorded on hanging request [fence.error=%d]!\n",
@@ -1565,6 +1546,7 @@ static int igt_atomic_reset_engine(struct intel_engine_cs *engine,
 		pr_err("%s(%s): Failed to start request %llx, at %x\n",
 		       __func__, engine->name,
 		       rq->fence.seqno, hws_seqno(&h, rq));
+		i915_gem_set_wedged(i915);
 		err = -EIO;
 	}
 
@@ -1588,7 +1570,6 @@ static int igt_atomic_reset_engine(struct intel_engine_cs *engine,
 static void force_reset(struct drm_i915_private *i915)
 {
 	i915_gem_set_wedged(i915);
-	set_bit(I915_RESET_HANDOFF, &i915->gpu_error.flags);
 	i915_reset(i915, 0, NULL);
 }
 
@@ -1618,6 +1599,26 @@ static int igt_atomic_reset(void *arg)
 	if (i915_terminally_wedged(&i915->gpu_error))
 		goto unlock;
 
+	if (intel_has_gpu_reset(i915)) {
+		const typeof(*phases) *p;
+
+		for (p = phases; p->name; p++) {
+			GEM_TRACE("intel_gpu_reset under %s\n", p->name);
+
+			p->critical_section_begin();
+			err = intel_gpu_reset(i915, ALL_ENGINES);
+			p->critical_section_end();
+
+			if (err) {
+				pr_err("intel_gpu_reset failed under %s\n",
+				       p->name);
+				goto out;
+			}
+		}
+
+		force_reset(i915);
+	}
+
 	if (intel_has_reset_engine(i915)) {
 		struct intel_engine_cs *engine;
 		enum intel_engine_id id;
diff --git a/drivers/gpu/drm/i915/selftests/intel_workarounds.c b/drivers/gpu/drm/i915/selftests/intel_workarounds.c
index a8cac56be835..b15c4f26c593 100644
--- a/drivers/gpu/drm/i915/selftests/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/selftests/intel_workarounds.c
@@ -214,7 +214,6 @@ static int check_whitelist(struct i915_gem_context *ctx,
 
 static int do_device_reset(struct intel_engine_cs *engine)
 {
-	set_bit(I915_RESET_HANDOFF, &engine->i915->gpu_error.flags);
 	i915_reset(engine->i915, ENGINE_MASK(engine->id), "live_workarounds");
 	return 0;
 }
@@ -394,7 +393,6 @@ static int
 live_gpu_reset_gt_engine_workarounds(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
-	struct i915_gpu_error *error = &i915->gpu_error;
 	intel_wakeref_t wakeref;
 	struct wa_lists lists;
 	bool ok;
@@ -413,7 +411,6 @@ live_gpu_reset_gt_engine_workarounds(void *arg)
 	if (!ok)
 		goto out;
 
-	set_bit(I915_RESET_HANDOFF, &error->flags);
 	i915_reset(i915, ALL_ENGINES, "live_workarounds");
 
 	ok = verify_gt_engine_wa(i915, &lists, "after reset");
-- 
2.20.1

_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 04/23] drm/i915/selftests: Trim struct_mutex duration for set-wedged selftest
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (2 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 03/23] drm/i915: Remove GPU reset dependence on struct_mutex Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 14:34 ` [PATCH 05/23] drm/i915: Issue engine resets onto idle engines Chris Wilson
                   ` (23 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx; +Cc: Mika Kuoppala

Trim the struct_mutex hold and exclude the call to i915_gem_set_wedged()
as a reminder that it must be callable without struct_mutex held.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
---
 drivers/gpu/drm/i915/selftests/intel_hangcheck.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
index 67431355cd6e..28144fd72550 100644
--- a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
+++ b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
@@ -389,16 +389,16 @@ static int igt_wedged_reset(void *arg)
 	/* Check that we can recover a wedged device with a GPU reset */
 
 	igt_global_reset_lock(i915);
-	mutex_lock(&i915->drm.struct_mutex);
 	wakeref = intel_runtime_pm_get(i915);
 
 	i915_gem_set_wedged(i915);
-	GEM_BUG_ON(!i915_terminally_wedged(&i915->gpu_error));
 
+	mutex_lock(&i915->drm.struct_mutex);
+	GEM_BUG_ON(!i915_terminally_wedged(&i915->gpu_error));
 	i915_reset(i915, ALL_ENGINES, NULL);
+	mutex_unlock(&i915->drm.struct_mutex);
 
 	intel_runtime_pm_put(i915, wakeref);
-	mutex_unlock(&i915->drm.struct_mutex);
 	igt_global_reset_unlock(i915);
 
 	return i915_terminally_wedged(&i915->gpu_error) ? -EIO : 0;
-- 
2.20.1

_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 05/23] drm/i915: Issue engine resets onto idle engines
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (3 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 04/23] drm/i915/selftests: Trim struct_mutex duration for set-wedged selftest Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-18 12:06   ` Mika Kuoppala
  2019-01-17 14:34 ` [PATCH 06/23] drm/i915: Stop tracking MRU activity on VMA Chris Wilson
                   ` (22 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Always perform the requested reset, even if we believe the engine is
idle. Presumably there was a reason the caller wanted the reset, and in
the near future we lose the easy tracking for whether the engine is
idle.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_reset.c             |  4 ----
 .../gpu/drm/i915/selftests/intel_hangcheck.c  | 22 +++++--------------
 2 files changed, 6 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index 064fc6da1512..d44b095e2860 100644
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -1063,10 +1063,6 @@ int i915_reset_engine(struct intel_engine_cs *engine, const char *msg)
 	GEM_TRACE("%s flags=%lx\n", engine->name, error->flags);
 	GEM_BUG_ON(!test_bit(I915_RESET_ENGINE + engine->id, &error->flags));
 
-	if (i915_seqno_passed(intel_engine_get_seqno(engine),
-			      intel_engine_last_submit(engine)))
-		return 0;
-
 	reset_prepare_engine(engine);
 
 	if (msg)
diff --git a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
index 28144fd72550..9d0cc9d63a1e 100644
--- a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
+++ b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
@@ -449,8 +449,6 @@ static int __igt_reset_engine(struct drm_i915_private *i915, bool active)
 
 		set_bit(I915_RESET_ENGINE + id, &i915->gpu_error.flags);
 		do {
-			u32 seqno = intel_engine_get_seqno(engine);
-
 			if (active) {
 				struct i915_request *rq;
 
@@ -479,8 +477,6 @@ static int __igt_reset_engine(struct drm_i915_private *i915, bool active)
 					break;
 				}
 
-				GEM_BUG_ON(!rq->global_seqno);
-				seqno = rq->global_seqno - 1;
 				i915_request_put(rq);
 			}
 
@@ -496,11 +492,10 @@ static int __igt_reset_engine(struct drm_i915_private *i915, bool active)
 				break;
 			}
 
-			reset_engine_count += active;
 			if (i915_reset_engine_count(&i915->gpu_error, engine) !=
-			    reset_engine_count) {
-				pr_err("%s engine reset %srecorded!\n",
-				       engine->name, active ? "not " : "");
+			    ++reset_engine_count) {
+				pr_err("%s engine reset not recorded!\n",
+				       engine->name);
 				err = -EINVAL;
 				break;
 			}
@@ -728,7 +723,6 @@ static int __igt_reset_engines(struct drm_i915_private *i915,
 
 		set_bit(I915_RESET_ENGINE + id, &i915->gpu_error.flags);
 		do {
-			u32 seqno = intel_engine_get_seqno(engine);
 			struct i915_request *rq = NULL;
 
 			if (flags & TEST_ACTIVE) {
@@ -756,9 +750,6 @@ static int __igt_reset_engines(struct drm_i915_private *i915,
 					err = -EIO;
 					break;
 				}
-
-				GEM_BUG_ON(!rq->global_seqno);
-				seqno = rq->global_seqno - 1;
 			}
 
 			err = i915_reset_engine(engine, NULL);
@@ -795,10 +786,9 @@ static int __igt_reset_engines(struct drm_i915_private *i915,
 
 		reported = i915_reset_engine_count(&i915->gpu_error, engine);
 		reported -= threads[engine->id].resets;
-		if (reported != (flags & TEST_ACTIVE ? count : 0)) {
-			pr_err("i915_reset_engine(%s:%s): reset %lu times, but reported %lu, expected %lu reported\n",
-			       engine->name, test_name, count, reported,
-			       (flags & TEST_ACTIVE ? count : 0));
+		if (reported != count) {
+			pr_err("i915_reset_engine(%s:%s): reset %lu times, but reported %lu\n",
+			       engine->name, test_name, count, reported);
 			if (!err)
 				err = -EINVAL;
 		}
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 06/23] drm/i915: Stop tracking MRU activity on VMA
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (4 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 05/23] drm/i915: Issue engine resets onto idle engines Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 14:34 ` [PATCH 07/23] drm/i915: Pull VM lists under the VM mutex Chris Wilson
                   ` (21 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Our goal is to remove struct_mutex and replace it with fine grained
locking. One of the thorny issues is our eviction logic for reclaiming
space for an execbuffer (or GTT mmaping, among a few other examples).
While eviction itself is easy to move under a per-VM mutex, performing
the activity tracking is less agreeable. One solution is not to do any
MRU tracking and do a simple coarse evaluation during eviction of
active/inactive, with a loose temporal ordering of last
insertion/evaluation. That keeps all the locking constrained to when we
are manipulating the VM itself, neatly avoiding the tricky handling of
possible recursive locking during execbuf and elsewhere.

Note that discarding the MRU is unlikely to impact upon our efficiency
to reclaim VM space (where we think a LRU model is best) as our
current strategy is to use random idle replacement first before doing
a search, and over time the use of softpinned 48b per-ppGTT is growing
(thereby eliminating any need to perform any eviction searches, in
theory at least).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.c               | 10 +--
 drivers/gpu/drm/i915/i915_gem_evict.c         | 71 ++++++++++++-------
 drivers/gpu/drm/i915/i915_gem_gtt.c           | 15 ++--
 drivers/gpu/drm/i915/i915_gem_gtt.h           | 26 +------
 drivers/gpu/drm/i915/i915_gem_shrinker.c      |  8 ++-
 drivers/gpu/drm/i915/i915_gem_stolen.c        |  3 +-
 drivers/gpu/drm/i915/i915_gpu_error.c         | 37 +++++-----
 drivers/gpu/drm/i915/i915_vma.c               |  9 +--
 .../gpu/drm/i915/selftests/i915_gem_evict.c   |  4 +-
 drivers/gpu/drm/i915/selftests/i915_gem_gtt.c |  2 +-
 10 files changed, 84 insertions(+), 101 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index d20b42386c3c..f45186ddb236 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -253,10 +253,7 @@ i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
 
 	pinned = ggtt->vm.reserved;
 	mutex_lock(&dev->struct_mutex);
-	list_for_each_entry(vma, &ggtt->vm.active_list, vm_link)
-		if (i915_vma_is_pinned(vma))
-			pinned += vma->node.size;
-	list_for_each_entry(vma, &ggtt->vm.inactive_list, vm_link)
+	list_for_each_entry(vma, &ggtt->vm.bound_list, vm_link)
 		if (i915_vma_is_pinned(vma))
 			pinned += vma->node.size;
 	mutex_unlock(&dev->struct_mutex);
@@ -1539,13 +1536,10 @@ static void i915_gem_object_bump_inactive_ggtt(struct drm_i915_gem_object *obj)
 	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
 
 	for_each_ggtt_vma(vma, obj) {
-		if (i915_vma_is_active(vma))
-			continue;
-
 		if (!drm_mm_node_allocated(&vma->node))
 			continue;
 
-		list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
+		list_move_tail(&vma->vm_link, &vma->vm->bound_list);
 	}
 
 	i915 = to_i915(obj->base.dev);
diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
index f6855401f247..5cfe4b75e7d6 100644
--- a/drivers/gpu/drm/i915/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/i915_gem_evict.c
@@ -126,14 +126,10 @@ i915_gem_evict_something(struct i915_address_space *vm,
 	struct drm_i915_private *dev_priv = vm->i915;
 	struct drm_mm_scan scan;
 	struct list_head eviction_list;
-	struct list_head *phases[] = {
-		&vm->inactive_list,
-		&vm->active_list,
-		NULL,
-	}, **phase;
 	struct i915_vma *vma, *next;
 	struct drm_mm_node *node;
 	enum drm_mm_insert_mode mode;
+	struct i915_vma *active;
 	int ret;
 
 	lockdep_assert_held(&vm->i915->drm.struct_mutex);
@@ -169,17 +165,46 @@ i915_gem_evict_something(struct i915_address_space *vm,
 	 */
 	if (!(flags & PIN_NONBLOCK))
 		i915_retire_requests(dev_priv);
-	else
-		phases[1] = NULL;
 
 search_again:
+	active = NULL;
 	INIT_LIST_HEAD(&eviction_list);
-	phase = phases;
-	do {
-		list_for_each_entry(vma, *phase, vm_link)
-			if (mark_free(&scan, vma, flags, &eviction_list))
-				goto found;
-	} while (*++phase);
+	list_for_each_entry_safe(vma, next, &vm->bound_list, vm_link) {
+		/*
+		 * We keep this list in a rough least-recently scanned order
+		 * of active elements (inactive elements are cheap to reap).
+		 * New entries are added to the end, and we move anything we
+		 * scan to the end. The assumption is that the working set
+		 * of applications is either steady state (and thanks to the
+		 * userspace bo cache it almost always is) or volatile and
+		 * frequently replaced after a frame, which are self-evicting!
+		 * Given that assumption, the MRU order of the scan list is
+		 * fairly static, and keeping it in least-recently scan order
+		 * is suitable.
+		 *
+		 * To notice when we complete one full cycle, we record the
+		 * first active element seen, before moving it to the tail.
+		 */
+		if (i915_vma_is_active(vma)) {
+			if (vma == active) {
+				if (flags & PIN_NONBLOCK)
+					break;
+
+				active = ERR_PTR(-EAGAIN);
+			}
+
+			if (active != ERR_PTR(-EAGAIN)) {
+				if (!active)
+					active = vma;
+
+				list_move_tail(&vma->vm_link, &vm->bound_list);
+				continue;
+			}
+		}
+
+		if (mark_free(&scan, vma, flags, &eviction_list))
+			goto found;
+	}
 
 	/* Nothing found, clean up and bail out! */
 	list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
@@ -388,11 +413,6 @@ int i915_gem_evict_for_node(struct i915_address_space *vm,
  */
 int i915_gem_evict_vm(struct i915_address_space *vm)
 {
-	struct list_head *phases[] = {
-		&vm->inactive_list,
-		&vm->active_list,
-		NULL
-	}, **phase;
 	struct list_head eviction_list;
 	struct i915_vma *vma, *next;
 	int ret;
@@ -412,16 +432,13 @@ int i915_gem_evict_vm(struct i915_address_space *vm)
 	}
 
 	INIT_LIST_HEAD(&eviction_list);
-	phase = phases;
-	do {
-		list_for_each_entry(vma, *phase, vm_link) {
-			if (i915_vma_is_pinned(vma))
-				continue;
+	list_for_each_entry(vma, &vm->bound_list, vm_link) {
+		if (i915_vma_is_pinned(vma))
+			continue;
 
-			__i915_vma_pin(vma);
-			list_add(&vma->evict_link, &eviction_list);
-		}
-	} while (*++phase);
+		__i915_vma_pin(vma);
+		list_add(&vma->evict_link, &eviction_list);
+	}
 
 	ret = 0;
 	list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 9081e3bc5a59..2ad9070a54c1 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -491,9 +491,8 @@ static void i915_address_space_init(struct i915_address_space *vm, int subclass)
 
 	stash_init(&vm->free_pages);
 
-	INIT_LIST_HEAD(&vm->active_list);
-	INIT_LIST_HEAD(&vm->inactive_list);
 	INIT_LIST_HEAD(&vm->unbound_list);
+	INIT_LIST_HEAD(&vm->bound_list);
 }
 
 static void i915_address_space_fini(struct i915_address_space *vm)
@@ -2111,8 +2110,7 @@ void i915_ppgtt_close(struct i915_address_space *vm)
 static void ppgtt_destroy_vma(struct i915_address_space *vm)
 {
 	struct list_head *phases[] = {
-		&vm->active_list,
-		&vm->inactive_list,
+		&vm->bound_list,
 		&vm->unbound_list,
 		NULL,
 	}, **phase;
@@ -2135,8 +2133,7 @@ void i915_ppgtt_release(struct kref *kref)
 
 	ppgtt_destroy_vma(&ppgtt->vm);
 
-	GEM_BUG_ON(!list_empty(&ppgtt->vm.active_list));
-	GEM_BUG_ON(!list_empty(&ppgtt->vm.inactive_list));
+	GEM_BUG_ON(!list_empty(&ppgtt->vm.bound_list));
 	GEM_BUG_ON(!list_empty(&ppgtt->vm.unbound_list));
 
 	ppgtt->vm.cleanup(&ppgtt->vm);
@@ -2801,8 +2798,7 @@ void i915_ggtt_cleanup_hw(struct drm_i915_private *dev_priv)
 	mutex_lock(&dev_priv->drm.struct_mutex);
 	i915_gem_fini_aliasing_ppgtt(dev_priv);
 
-	GEM_BUG_ON(!list_empty(&ggtt->vm.active_list));
-	list_for_each_entry_safe(vma, vn, &ggtt->vm.inactive_list, vm_link)
+	list_for_each_entry_safe(vma, vn, &ggtt->vm.bound_list, vm_link)
 		WARN_ON(i915_vma_unbind(vma));
 
 	if (drm_mm_node_allocated(&ggtt->error_capture))
@@ -3514,8 +3510,7 @@ void i915_gem_restore_gtt_mappings(struct drm_i915_private *dev_priv)
 	ggtt->vm.closed = true; /* skip rewriting PTE on VMA unbind */
 
 	/* clflush objects bound into the GGTT and rebind them. */
-	GEM_BUG_ON(!list_empty(&ggtt->vm.active_list));
-	list_for_each_entry_safe(vma, vn, &ggtt->vm.inactive_list, vm_link) {
+	list_for_each_entry_safe(vma, vn, &ggtt->vm.bound_list, vm_link) {
 		struct drm_i915_gem_object *obj = vma->obj;
 
 		if (!(vma->flags & I915_VMA_GLOBAL_BIND))
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index a0039ea97cdc..bd679c8c56dd 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -299,32 +299,12 @@ struct i915_address_space {
 	struct i915_page_directory_pointer *scratch_pdp; /* GEN8+ & 48b PPGTT */
 
 	/**
-	 * List of objects currently involved in rendering.
-	 *
-	 * Includes buffers having the contents of their GPU caches
-	 * flushed, not necessarily primitives. last_read_req
-	 * represents when the rendering involved will be completed.
-	 *
-	 * A reference is held on the buffer while on this list.
+	 * List of vma currently bound.
 	 */
-	struct list_head active_list;
+	struct list_head bound_list;
 
 	/**
-	 * LRU list of objects which are not in the ringbuffer and
-	 * are ready to unbind, but are still in the GTT.
-	 *
-	 * last_read_req is NULL while an object is in this list.
-	 *
-	 * A reference is not held on the buffer while on this list,
-	 * as merely being GTT-bound shouldn't prevent its being
-	 * freed, and we'll pull it off the list in the free path.
-	 */
-	struct list_head inactive_list;
-
-	/**
-	 * List of vma that have been unbound.
-	 *
-	 * A reference is not held on the buffer while on this list.
+	 * List of vma that are not unbound.
 	 */
 	struct list_head unbound_list;
 
diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c
index 8ceecb026910..a76d6c95c824 100644
--- a/drivers/gpu/drm/i915/i915_gem_shrinker.c
+++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c
@@ -462,9 +462,13 @@ i915_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr
 
 	/* We also want to clear any cached iomaps as they wrap vmap */
 	list_for_each_entry_safe(vma, next,
-				 &i915->ggtt.vm.inactive_list, vm_link) {
+				 &i915->ggtt.vm.bound_list, vm_link) {
 		unsigned long count = vma->node.size >> PAGE_SHIFT;
-		if (vma->iomap && i915_vma_unbind(vma) == 0)
+
+		if (!vma->iomap || i915_vma_is_active(vma))
+			continue;
+
+		if (i915_vma_unbind(vma) == 0)
 			freed_pages += count;
 	}
 
diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 9df615eea2d8..a9e365789686 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -701,7 +701,8 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *dev_priv
 	vma->pages = obj->mm.pages;
 	vma->flags |= I915_VMA_GLOBAL_BIND;
 	__i915_vma_set_map_and_fenceable(vma);
-	list_move_tail(&vma->vm_link, &ggtt->vm.inactive_list);
+
+	list_move_tail(&vma->vm_link, &ggtt->vm.bound_list);
 
 	spin_lock(&dev_priv->mm.obj_lock);
 	list_move_tail(&obj->mm.link, &dev_priv->mm.bound_list);
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 1f8e80e31b49..5914ed5e3735 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -1124,7 +1124,7 @@ static void capture_bo(struct drm_i915_error_buffer *err,
 
 static u32 capture_error_bo(struct drm_i915_error_buffer *err,
 			    int count, struct list_head *head,
-			    bool pinned_only)
+			    bool active_only, bool pinned_only)
 {
 	struct i915_vma *vma;
 	int i = 0;
@@ -1133,6 +1133,9 @@ static u32 capture_error_bo(struct drm_i915_error_buffer *err,
 		if (!vma->obj)
 			continue;
 
+		if (active_only && !i915_vma_is_active(vma))
+			continue;
+
 		if (pinned_only && !i915_vma_is_pinned(vma))
 			continue;
 
@@ -1610,14 +1613,16 @@ static void gem_capture_vm(struct i915_gpu_state *error,
 	int count;
 
 	count = 0;
-	list_for_each_entry(vma, &vm->active_list, vm_link)
-		count++;
+	list_for_each_entry(vma, &vm->bound_list, vm_link)
+		if (i915_vma_is_active(vma))
+			count++;
 
 	active_bo = NULL;
 	if (count)
 		active_bo = kcalloc(count, sizeof(*active_bo), GFP_ATOMIC);
 	if (active_bo)
-		count = capture_error_bo(active_bo, count, &vm->active_list, false);
+		count = capture_error_bo(active_bo, count, &vm->bound_list,
+					 true, false);
 	else
 		count = 0;
 
@@ -1655,28 +1660,20 @@ static void capture_pinned_buffers(struct i915_gpu_state *error)
 	struct i915_address_space *vm = &error->i915->ggtt.vm;
 	struct drm_i915_error_buffer *bo;
 	struct i915_vma *vma;
-	int count_inactive, count_active;
-
-	count_inactive = 0;
-	list_for_each_entry(vma, &vm->inactive_list, vm_link)
-		count_inactive++;
+	int count;
 
-	count_active = 0;
-	list_for_each_entry(vma, &vm->active_list, vm_link)
-		count_active++;
+	count = 0;
+	list_for_each_entry(vma, &vm->bound_list, vm_link)
+		count++;
 
 	bo = NULL;
-	if (count_inactive + count_active)
-		bo = kcalloc(count_inactive + count_active,
-			     sizeof(*bo), GFP_ATOMIC);
+	if (count)
+		bo = kcalloc(count, sizeof(*bo), GFP_ATOMIC);
 	if (!bo)
 		return;
 
-	count_inactive = capture_error_bo(bo, count_inactive,
-					  &vm->active_list, true);
-	count_active = capture_error_bo(bo + count_inactive, count_active,
-					&vm->inactive_list, true);
-	error->pinned_bo_count = count_inactive + count_active;
+	error->pinned_bo_count =
+		capture_error_bo(bo, count, &vm->bound_list, false, true);
 	error->pinned_bo = bo;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 5b4d78cdb4ca..7de28baffb8f 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -79,9 +79,6 @@ __i915_vma_retire(struct i915_vma *vma, struct i915_request *rq)
 	if (--vma->active_count)
 		return;
 
-	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
-	list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
-
 	GEM_BUG_ON(!i915_gem_object_is_active(obj));
 	if (--obj->active_count)
 		return;
@@ -659,7 +656,7 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
 	GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, cache_level));
 
-	list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
+	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
 
 	if (vma->obj) {
 		struct drm_i915_gem_object *obj = vma->obj;
@@ -1003,10 +1000,8 @@ int i915_vma_move_to_active(struct i915_vma *vma,
 	 * add the active reference first and queue for it to be dropped
 	 * *last*.
 	 */
-	if (!i915_gem_active_isset(active) && !vma->active_count++) {
-		list_move_tail(&vma->vm_link, &vma->vm->active_list);
+	if (!i915_gem_active_isset(active) && !vma->active_count++)
 		obj->active_count++;
-	}
 	i915_gem_active_set(active, rq);
 	GEM_BUG_ON(!i915_vma_is_active(vma));
 	GEM_BUG_ON(!obj->active_count);
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
index 067e5dfa0a24..6c9c7a1c2728 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
@@ -57,7 +57,7 @@ static int populate_ggtt(struct drm_i915_private *i915)
 		return -EINVAL;
 	}
 
-	if (list_empty(&i915->ggtt.vm.inactive_list)) {
+	if (list_empty(&i915->ggtt.vm.bound_list)) {
 		pr_err("No objects on the GGTT inactive list!\n");
 		return -EINVAL;
 	}
@@ -69,7 +69,7 @@ static void unpin_ggtt(struct drm_i915_private *i915)
 {
 	struct i915_vma *vma;
 
-	list_for_each_entry(vma, &i915->ggtt.vm.inactive_list, vm_link)
+	list_for_each_entry(vma, &i915->ggtt.vm.bound_list, vm_link)
 		i915_vma_unpin(vma);
 }
 
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
index fea8ab14e79d..852b06cb50a0 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
@@ -1237,7 +1237,7 @@ static void track_vma_bind(struct i915_vma *vma)
 	__i915_gem_object_pin_pages(obj);
 
 	vma->pages = obj->mm.pages;
-	list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
+	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
 }
 
 static int exercise_mock(struct drm_i915_private *i915,
-- 
2.20.1

_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 07/23] drm/i915: Pull VM lists under the VM mutex.
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (5 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 06/23] drm/i915: Stop tracking MRU activity on VMA Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-18 10:07   ` Tvrtko Ursulin
  2019-01-17 14:34 ` [PATCH 08/23] drm/i915: Move vma lookup to its own lock Chris Wilson
                   ` (20 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

A starting point to counter the pervasive struct_mutex. For the goal of
avoiding (or at least blocking under them!) global locks during user
request submission, a simple but important step is being able to manage
each clients GTT separately. For which, we want to replace using the
struct_mutex as the guard for all things GTT/VM and switch instead to a
specific mutex inside i915_address_space.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.c                 | 14 ++++++++------
 drivers/gpu/drm/i915/i915_gem_evict.c           |  2 ++
 drivers/gpu/drm/i915/i915_gem_gtt.c             | 15 +++++++++++++--
 drivers/gpu/drm/i915/i915_gem_shrinker.c        |  4 ++++
 drivers/gpu/drm/i915/i915_gem_stolen.c          |  2 ++
 drivers/gpu/drm/i915/i915_vma.c                 | 11 +++++++++++
 drivers/gpu/drm/i915/selftests/i915_gem_evict.c |  3 +++
 drivers/gpu/drm/i915/selftests/i915_gem_gtt.c   |  3 +++
 8 files changed, 46 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index f45186ddb236..538fa5404603 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -245,18 +245,19 @@ int
 i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
 			    struct drm_file *file)
 {
-	struct drm_i915_private *dev_priv = to_i915(dev);
-	struct i915_ggtt *ggtt = &dev_priv->ggtt;
+	struct i915_ggtt *ggtt = &to_i915(dev)->ggtt;
 	struct drm_i915_gem_get_aperture *args = data;
 	struct i915_vma *vma;
 	u64 pinned;
 
+	mutex_lock(&ggtt->vm.mutex);
+
 	pinned = ggtt->vm.reserved;
-	mutex_lock(&dev->struct_mutex);
 	list_for_each_entry(vma, &ggtt->vm.bound_list, vm_link)
 		if (i915_vma_is_pinned(vma))
 			pinned += vma->node.size;
-	mutex_unlock(&dev->struct_mutex);
+
+	mutex_unlock(&ggtt->vm.mutex);
 
 	args->aper_size = ggtt->vm.total;
 	args->aper_available_size = args->aper_size - pinned;
@@ -1529,20 +1530,21 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
 
 static void i915_gem_object_bump_inactive_ggtt(struct drm_i915_gem_object *obj)
 {
-	struct drm_i915_private *i915;
+	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 	struct list_head *list;
 	struct i915_vma *vma;
 
 	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
 
+	mutex_lock(&i915->ggtt.vm.mutex);
 	for_each_ggtt_vma(vma, obj) {
 		if (!drm_mm_node_allocated(&vma->node))
 			continue;
 
 		list_move_tail(&vma->vm_link, &vma->vm->bound_list);
 	}
+	mutex_unlock(&i915->ggtt.vm.mutex);
 
-	i915 = to_i915(obj->base.dev);
 	spin_lock(&i915->mm.obj_lock);
 	list = obj->bind_count ? &i915->mm.bound_list : &i915->mm.unbound_list;
 	list_move_tail(&obj->mm.link, list);
diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
index 5cfe4b75e7d6..dc137701acb8 100644
--- a/drivers/gpu/drm/i915/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/i915_gem_evict.c
@@ -432,6 +432,7 @@ int i915_gem_evict_vm(struct i915_address_space *vm)
 	}
 
 	INIT_LIST_HEAD(&eviction_list);
+	mutex_lock(&vm->mutex);
 	list_for_each_entry(vma, &vm->bound_list, vm_link) {
 		if (i915_vma_is_pinned(vma))
 			continue;
@@ -439,6 +440,7 @@ int i915_gem_evict_vm(struct i915_address_space *vm)
 		__i915_vma_pin(vma);
 		list_add(&vma->evict_link, &eviction_list);
 	}
+	mutex_unlock(&vm->mutex);
 
 	ret = 0;
 	list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 2ad9070a54c1..49b00996a15e 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -1931,7 +1931,10 @@ static struct i915_vma *pd_vma_create(struct gen6_hw_ppgtt *ppgtt, int size)
 	vma->ggtt_view.type = I915_GGTT_VIEW_ROTATED; /* prevent fencing */
 
 	INIT_LIST_HEAD(&vma->obj_link);
+
+	mutex_lock(&vma->vm->mutex);
 	list_add(&vma->vm_link, &vma->vm->unbound_list);
+	mutex_unlock(&vma->vm->mutex);
 
 	return vma;
 }
@@ -3504,9 +3507,10 @@ void i915_gem_restore_gtt_mappings(struct drm_i915_private *dev_priv)
 
 	i915_check_and_clear_faults(dev_priv);
 
+	mutex_lock(&ggtt->vm.mutex);
+
 	/* First fill our portion of the GTT with scratch pages */
 	ggtt->vm.clear_range(&ggtt->vm, 0, ggtt->vm.total);
-
 	ggtt->vm.closed = true; /* skip rewriting PTE on VMA unbind */
 
 	/* clflush objects bound into the GGTT and rebind them. */
@@ -3516,19 +3520,26 @@ void i915_gem_restore_gtt_mappings(struct drm_i915_private *dev_priv)
 		if (!(vma->flags & I915_VMA_GLOBAL_BIND))
 			continue;
 
+		mutex_unlock(&ggtt->vm.mutex);
+
 		if (!i915_vma_unbind(vma))
-			continue;
+			goto lock;
 
 		WARN_ON(i915_vma_bind(vma,
 				      obj ? obj->cache_level : 0,
 				      PIN_UPDATE));
 		if (obj)
 			WARN_ON(i915_gem_object_set_to_gtt_domain(obj, false));
+
+lock:
+		mutex_lock(&ggtt->vm.mutex);
 	}
 
 	ggtt->vm.closed = false;
 	i915_ggtt_invalidate(dev_priv);
 
+	mutex_unlock(&ggtt->vm.mutex);
+
 	if (INTEL_GEN(dev_priv) >= 8) {
 		struct intel_ppat *ppat = &dev_priv->ppat;
 
diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c
index a76d6c95c824..6da795c7e62e 100644
--- a/drivers/gpu/drm/i915/i915_gem_shrinker.c
+++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c
@@ -461,6 +461,7 @@ i915_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr
 					       I915_SHRINK_VMAPS);
 
 	/* We also want to clear any cached iomaps as they wrap vmap */
+	mutex_lock(&i915->ggtt.vm.mutex);
 	list_for_each_entry_safe(vma, next,
 				 &i915->ggtt.vm.bound_list, vm_link) {
 		unsigned long count = vma->node.size >> PAGE_SHIFT;
@@ -468,9 +469,12 @@ i915_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr
 		if (!vma->iomap || i915_vma_is_active(vma))
 			continue;
 
+		mutex_unlock(&i915->ggtt.vm.mutex);
 		if (i915_vma_unbind(vma) == 0)
 			freed_pages += count;
+		mutex_lock(&i915->ggtt.vm.mutex);
 	}
+	mutex_unlock(&i915->ggtt.vm.mutex);
 
 out:
 	shrinker_unlock(i915, unlock);
diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index a9e365789686..74a9661479ca 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -702,7 +702,9 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *dev_priv
 	vma->flags |= I915_VMA_GLOBAL_BIND;
 	__i915_vma_set_map_and_fenceable(vma);
 
+	mutex_lock(&ggtt->vm.mutex);
 	list_move_tail(&vma->vm_link, &ggtt->vm.bound_list);
+	mutex_unlock(&ggtt->vm.mutex);
 
 	spin_lock(&dev_priv->mm.obj_lock);
 	list_move_tail(&obj->mm.link, &dev_priv->mm.bound_list);
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 7de28baffb8f..dcbd0d345c72 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -213,7 +213,10 @@ vma_create(struct drm_i915_gem_object *obj,
 	}
 	rb_link_node(&vma->obj_node, rb, p);
 	rb_insert_color(&vma->obj_node, &obj->vma_tree);
+
+	mutex_lock(&vm->mutex);
 	list_add(&vma->vm_link, &vm->unbound_list);
+	mutex_unlock(&vm->mutex);
 
 	return vma;
 
@@ -656,7 +659,9 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
 	GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, cache_level));
 
+	mutex_lock(&vma->vm->mutex);
 	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
+	mutex_unlock(&vma->vm->mutex);
 
 	if (vma->obj) {
 		struct drm_i915_gem_object *obj = vma->obj;
@@ -689,8 +694,10 @@ i915_vma_remove(struct i915_vma *vma)
 
 	vma->ops->clear_pages(vma);
 
+	mutex_lock(&vma->vm->mutex);
 	drm_mm_remove_node(&vma->node);
 	list_move_tail(&vma->vm_link, &vma->vm->unbound_list);
+	mutex_unlock(&vma->vm->mutex);
 
 	/*
 	 * Since the unbound list is global, only move to that list if
@@ -802,7 +809,11 @@ static void __i915_vma_destroy(struct i915_vma *vma)
 	GEM_BUG_ON(i915_gem_active_isset(&vma->last_fence));
 
 	list_del(&vma->obj_link);
+
+	mutex_lock(&vma->vm->mutex);
 	list_del(&vma->vm_link);
+	mutex_unlock(&vma->vm->mutex);
+
 	if (vma->obj)
 		rb_erase(&vma->obj_node, &vma->obj->vma_tree);
 
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
index 6c9c7a1c2728..fb7df895afeb 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
@@ -67,10 +67,13 @@ static int populate_ggtt(struct drm_i915_private *i915)
 
 static void unpin_ggtt(struct drm_i915_private *i915)
 {
+	struct i915_ggtt *ggtt = &i915->ggtt;
 	struct i915_vma *vma;
 
+	mutex_lock(&ggtt->vm.mutex);
 	list_for_each_entry(vma, &i915->ggtt.vm.bound_list, vm_link)
 		i915_vma_unpin(vma);
+	mutex_unlock(&ggtt->vm.mutex);
 }
 
 static void cleanup_objects(struct drm_i915_private *i915)
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
index 852b06cb50a0..35eb40e5de91 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
@@ -1237,7 +1237,10 @@ static void track_vma_bind(struct i915_vma *vma)
 	__i915_gem_object_pin_pages(obj);
 
 	vma->pages = obj->mm.pages;
+
+	mutex_lock(&vma->vm->mutex);
 	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
+	mutex_unlock(&vma->vm->mutex);
 }
 
 static int exercise_mock(struct drm_i915_private *i915,
-- 
2.20.1

_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 08/23] drm/i915: Move vma lookup to its own lock
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (6 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 07/23] drm/i915: Pull VM lists under the VM mutex Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 16:27   ` Tvrtko Ursulin
  2019-01-17 14:34 ` [PATCH 09/23] drm/i915: Use b->irq_enable() as predicate for mock engine Chris Wilson
                   ` (19 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Remove the struct_mutex requirement for looking up the vma for an
object.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_debugfs.c       |  6 +--
 drivers/gpu/drm/i915/i915_gem.c           | 33 +++++++------
 drivers/gpu/drm/i915/i915_gem_object.h    | 45 ++++++++++-------
 drivers/gpu/drm/i915/i915_vma.c           | 60 +++++++++++++++--------
 drivers/gpu/drm/i915/i915_vma.h           |  2 +-
 drivers/gpu/drm/i915/selftests/i915_vma.c |  4 +-
 6 files changed, 92 insertions(+), 58 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index ba7f05b493ed..d052329c2319 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -159,14 +159,14 @@ describe_obj(struct seq_file *m, struct drm_i915_gem_object *obj)
 		   obj->mm.madv == I915_MADV_DONTNEED ? " purgeable" : "");
 	if (obj->base.name)
 		seq_printf(m, " (name: %d)", obj->base.name);
-	list_for_each_entry(vma, &obj->vma_list, obj_link) {
+	list_for_each_entry(vma, &obj->vma.list, obj_link) {
 		if (i915_vma_is_pinned(vma))
 			pin_count++;
 	}
 	seq_printf(m, " (pinned x %d)", pin_count);
 	if (obj->pin_global)
 		seq_printf(m, " (global)");
-	list_for_each_entry(vma, &obj->vma_list, obj_link) {
+	list_for_each_entry(vma, &obj->vma.list, obj_link) {
 		if (!drm_mm_node_allocated(&vma->node))
 			continue;
 
@@ -322,7 +322,7 @@ static int per_file_stats(int id, void *ptr, void *data)
 	if (obj->base.name || obj->base.dma_buf)
 		stats->shared += obj->base.size;
 
-	list_for_each_entry(vma, &obj->vma_list, obj_link) {
+	list_for_each_entry(vma, &obj->vma.list, obj_link) {
 		if (!drm_mm_node_allocated(&vma->node))
 			continue;
 
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 538fa5404603..15acd052da46 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -437,15 +437,19 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj)
 	if (ret)
 		return ret;
 
-	while ((vma = list_first_entry_or_null(&obj->vma_list,
-					       struct i915_vma,
-					       obj_link))) {
+	spin_lock(&obj->vma.lock);
+	while (!ret && (vma = list_first_entry_or_null(&obj->vma.list,
+						       struct i915_vma,
+						       obj_link))) {
 		list_move_tail(&vma->obj_link, &still_in_list);
+		spin_unlock(&obj->vma.lock);
+
 		ret = i915_vma_unbind(vma);
-		if (ret)
-			break;
+
+		spin_lock(&obj->vma.lock);
 	}
-	list_splice(&still_in_list, &obj->vma_list);
+	list_splice(&still_in_list, &obj->vma.list);
+	spin_unlock(&obj->vma.lock);
 
 	return ret;
 }
@@ -3489,7 +3493,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
 	 * reading an invalid PTE on older architectures.
 	 */
 restart:
-	list_for_each_entry(vma, &obj->vma_list, obj_link) {
+	list_for_each_entry(vma, &obj->vma.list, obj_link) {
 		if (!drm_mm_node_allocated(&vma->node))
 			continue;
 
@@ -3567,7 +3571,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
 			 */
 		}
 
-		list_for_each_entry(vma, &obj->vma_list, obj_link) {
+		list_for_each_entry(vma, &obj->vma.list, obj_link) {
 			if (!drm_mm_node_allocated(&vma->node))
 				continue;
 
@@ -3577,7 +3581,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
 		}
 	}
 
-	list_for_each_entry(vma, &obj->vma_list, obj_link)
+	list_for_each_entry(vma, &obj->vma.list, obj_link)
 		vma->node.color = cache_level;
 	i915_gem_object_set_cache_coherency(obj, cache_level);
 	obj->cache_dirty = true; /* Always invalidate stale cachelines */
@@ -4153,7 +4157,9 @@ void i915_gem_object_init(struct drm_i915_gem_object *obj,
 {
 	mutex_init(&obj->mm.lock);
 
-	INIT_LIST_HEAD(&obj->vma_list);
+	spin_lock_init(&obj->vma.lock);
+	INIT_LIST_HEAD(&obj->vma.list);
+
 	INIT_LIST_HEAD(&obj->lut_list);
 	INIT_LIST_HEAD(&obj->batch_pool_link);
 
@@ -4319,14 +4325,13 @@ static void __i915_gem_free_objects(struct drm_i915_private *i915,
 		mutex_lock(&i915->drm.struct_mutex);
 
 		GEM_BUG_ON(i915_gem_object_is_active(obj));
-		list_for_each_entry_safe(vma, vn,
-					 &obj->vma_list, obj_link) {
+		list_for_each_entry_safe(vma, vn, &obj->vma.list, obj_link) {
 			GEM_BUG_ON(i915_vma_is_active(vma));
 			vma->flags &= ~I915_VMA_PIN_MASK;
 			i915_vma_destroy(vma);
 		}
-		GEM_BUG_ON(!list_empty(&obj->vma_list));
-		GEM_BUG_ON(!RB_EMPTY_ROOT(&obj->vma_tree));
+		GEM_BUG_ON(!list_empty(&obj->vma.list));
+		GEM_BUG_ON(!RB_EMPTY_ROOT(&obj->vma.tree));
 
 		/* This serializes freeing with the shrinker. Since the free
 		 * is delayed, first by RCU then by the workqueue, we want the
diff --git a/drivers/gpu/drm/i915/i915_gem_object.h b/drivers/gpu/drm/i915/i915_gem_object.h
index cb1b0144d274..5a33b6d9f942 100644
--- a/drivers/gpu/drm/i915/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/i915_gem_object.h
@@ -87,24 +87,33 @@ struct drm_i915_gem_object {
 
 	const struct drm_i915_gem_object_ops *ops;
 
-	/**
-	 * @vma_list: List of VMAs backed by this object
-	 *
-	 * The VMA on this list are ordered by type, all GGTT vma are placed
-	 * at the head and all ppGTT vma are placed at the tail. The different
-	 * types of GGTT vma are unordered between themselves, use the
-	 * @vma_tree (which has a defined order between all VMA) to find an
-	 * exact match.
-	 */
-	struct list_head vma_list;
-	/**
-	 * @vma_tree: Ordered tree of VMAs backed by this object
-	 *
-	 * All VMA created for this object are placed in the @vma_tree for
-	 * fast retrieval via a binary search in i915_vma_instance().
-	 * They are also added to @vma_list for easy iteration.
-	 */
-	struct rb_root vma_tree;
+	struct {
+		/**
+		 * @vma.lock: protect the list/tree of vmas
+		 */
+		struct spinlock lock;
+
+		/**
+		 * @vma.list: List of VMAs backed by this object
+		 *
+		 * The VMA on this list are ordered by type, all GGTT vma are
+		 * placed at the head and all ppGTT vma are placed at the tail.
+		 * The different types of GGTT vma are unordered between
+		 * themselves, use the @vma.tree (which has a defined order
+		 * between all VMA) to quickly find an exact match.
+		 */
+		struct list_head list;
+
+		/**
+		 * @vma.tree: Ordered tree of VMAs backed by this object
+		 *
+		 * All VMA created for this object are placed in the @vma.tree
+		 * for fast retrieval via a binary search in
+		 * i915_vma_instance(). They are also added to @vma.list for
+		 * easy iteration.
+		 */
+		struct rb_root tree;
+	} vma;
 
 	/**
 	 * @lut_list: List of vma lookup entries in use for this object.
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index dcbd0d345c72..3a680fe2bb8b 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -187,32 +187,47 @@ vma_create(struct drm_i915_gem_object *obj,
 								i915_gem_object_get_stride(obj));
 		GEM_BUG_ON(!is_power_of_2(vma->fence_alignment));
 
-		/*
-		 * We put the GGTT vma at the start of the vma-list, followed
-		 * by the ppGGTT vma. This allows us to break early when
-		 * iterating over only the GGTT vma for an object, see
-		 * for_each_ggtt_vma()
-		 */
 		vma->flags |= I915_VMA_GGTT;
-		list_add(&vma->obj_link, &obj->vma_list);
-	} else {
-		list_add_tail(&vma->obj_link, &obj->vma_list);
 	}
 
+	spin_lock(&obj->vma.lock);
+
 	rb = NULL;
-	p = &obj->vma_tree.rb_node;
+	p = &obj->vma.tree.rb_node;
 	while (*p) {
 		struct i915_vma *pos;
+		long cmp;
 
 		rb = *p;
 		pos = rb_entry(rb, struct i915_vma, obj_node);
-		if (i915_vma_compare(pos, vm, view) < 0)
+
+		cmp = i915_vma_compare(pos, vm, view);
+		if (cmp == 0) {
+			spin_unlock(&obj->vma.lock);
+			kmem_cache_free(vm->i915->vmas, vma);
+			return pos;
+		}
+
+		if (cmp < 0)
 			p = &rb->rb_right;
 		else
 			p = &rb->rb_left;
 	}
 	rb_link_node(&vma->obj_node, rb, p);
-	rb_insert_color(&vma->obj_node, &obj->vma_tree);
+	rb_insert_color(&vma->obj_node, &obj->vma.tree);
+
+	if (i915_vma_is_ggtt(vma))
+		/*
+		 * We put the GGTT vma at the start of the vma-list, followed
+		 * by the ppGGTT vma. This allows us to break early when
+		 * iterating over only the GGTT vma for an object, see
+		 * for_each_ggtt_vma()
+		 */
+		list_add(&vma->obj_link, &obj->vma.list);
+	else
+		list_add_tail(&vma->obj_link, &obj->vma.list);
+
+	spin_unlock(&obj->vma.lock);
 
 	mutex_lock(&vm->mutex);
 	list_add(&vma->vm_link, &vm->unbound_list);
@@ -232,7 +247,7 @@ vma_lookup(struct drm_i915_gem_object *obj,
 {
 	struct rb_node *rb;
 
-	rb = obj->vma_tree.rb_node;
+	rb = obj->vma.tree.rb_node;
 	while (rb) {
 		struct i915_vma *vma = rb_entry(rb, struct i915_vma, obj_node);
 		long cmp;
@@ -272,16 +287,17 @@ i915_vma_instance(struct drm_i915_gem_object *obj,
 {
 	struct i915_vma *vma;
 
-	lockdep_assert_held(&obj->base.dev->struct_mutex);
 	GEM_BUG_ON(view && !i915_is_ggtt(vm));
 	GEM_BUG_ON(vm->closed);
 
+	spin_lock(&obj->vma.lock);
 	vma = vma_lookup(obj, vm, view);
-	if (!vma)
+	spin_unlock(&obj->vma.lock);
+
+	if (unlikely(!vma))
 		vma = vma_create(obj, vm, view);
 
 	GEM_BUG_ON(!IS_ERR(vma) && i915_vma_compare(vma, vm, view));
-	GEM_BUG_ON(!IS_ERR(vma) && vma_lookup(obj, vm, view) != vma);
 	return vma;
 }
 
@@ -808,14 +824,18 @@ static void __i915_vma_destroy(struct i915_vma *vma)
 
 	GEM_BUG_ON(i915_gem_active_isset(&vma->last_fence));
 
-	list_del(&vma->obj_link);
-
 	mutex_lock(&vma->vm->mutex);
 	list_del(&vma->vm_link);
 	mutex_unlock(&vma->vm->mutex);
 
-	if (vma->obj)
-		rb_erase(&vma->obj_node, &vma->obj->vma_tree);
+	if (vma->obj) {
+		struct drm_i915_gem_object *obj = vma->obj;
+
+		spin_lock(&obj->vma.lock);
+		list_del(&vma->obj_link);
+		rb_erase(&vma->obj_node, &vma->obj->vma.tree);
+		spin_unlock(&obj->vma.lock);
+	}
 
 	rbtree_postorder_for_each_entry_safe(iter, n, &vma->active, node) {
 		GEM_BUG_ON(i915_gem_active_isset(&iter->base));
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 4f7c1c7599f4..7252abc73d3e 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -425,7 +425,7 @@ void i915_vma_parked(struct drm_i915_private *i915);
  * or the list is empty ofc.
  */
 #define for_each_ggtt_vma(V, OBJ) \
-	list_for_each_entry(V, &(OBJ)->vma_list, obj_link)		\
+	list_for_each_entry(V, &(OBJ)->vma.list, obj_link)		\
 		for_each_until(!i915_vma_is_ggtt(V))
 
 #endif
diff --git a/drivers/gpu/drm/i915/selftests/i915_vma.c b/drivers/gpu/drm/i915/selftests/i915_vma.c
index ffa74290e054..f1008b07dfd2 100644
--- a/drivers/gpu/drm/i915/selftests/i915_vma.c
+++ b/drivers/gpu/drm/i915/selftests/i915_vma.c
@@ -670,7 +670,7 @@ static int igt_vma_partial(void *arg)
 		}
 
 		count = 0;
-		list_for_each_entry(vma, &obj->vma_list, obj_link)
+		list_for_each_entry(vma, &obj->vma.list, obj_link)
 			count++;
 		if (count != nvma) {
 			pr_err("(%s) All partial vma were not recorded on the obj->vma_list: found %u, expected %u\n",
@@ -699,7 +699,7 @@ static int igt_vma_partial(void *arg)
 		i915_vma_unpin(vma);
 
 		count = 0;
-		list_for_each_entry(vma, &obj->vma_list, obj_link)
+		list_for_each_entry(vma, &obj->vma.list, obj_link)
 			count++;
 		if (count != nvma) {
 			pr_err("(%s) allocated an extra full vma!\n", p->name);
-- 
2.20.1

_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 09/23] drm/i915: Use b->irq_enable() as predicate for mock engine
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (7 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 08/23] drm/i915: Move vma lookup to its own lock Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 16:44   ` Tvrtko Ursulin
  2019-01-17 14:34 ` [PATCH 10/23] drm/i915/selftests: Allocate mock ring/timeline per context Chris Wilson
                   ` (18 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Since commit  d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")
we have required a mechanism to avoid touching the interrupt hardware
for breadcrumbs, superseding our mock interface for selftests.

References: d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/intel_breadcrumbs.c     | 39 ++++++++------------
 drivers/gpu/drm/i915/intel_engine_cs.c       | 11 ++----
 drivers/gpu/drm/i915/intel_ringbuffer.h      |  1 -
 drivers/gpu/drm/i915/selftests/mock_engine.c |  1 -
 4 files changed, 20 insertions(+), 32 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c
index 4ed7105d7ff5..7b517bf83507 100644
--- a/drivers/gpu/drm/i915/intel_breadcrumbs.c
+++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
@@ -158,6 +158,9 @@ static void intel_breadcrumbs_fake_irq(struct timer_list *t)
 
 static void irq_enable(struct intel_engine_cs *engine)
 {
+	if (!engine->irq_enable)
+		return;
+
 	/*
 	 * FIXME: Ideally we want this on the API boundary, but for the
 	 * sake of testing with mock breadcrumbs (no HW so unable to
@@ -167,21 +170,20 @@ static void irq_enable(struct intel_engine_cs *engine)
 	GEM_BUG_ON(!intel_irqs_enabled(engine->i915));
 
 	/* Caller disables interrupts */
-	if (engine->irq_enable) {
-		spin_lock(&engine->i915->irq_lock);
-		engine->irq_enable(engine);
-		spin_unlock(&engine->i915->irq_lock);
-	}
+	spin_lock(&engine->i915->irq_lock);
+	engine->irq_enable(engine);
+	spin_unlock(&engine->i915->irq_lock);
 }
 
 static void irq_disable(struct intel_engine_cs *engine)
 {
+	if (!engine->irq_disable)
+		return;
+
 	/* Caller disables interrupts */
-	if (engine->irq_disable) {
-		spin_lock(&engine->i915->irq_lock);
-		engine->irq_disable(engine);
-		spin_unlock(&engine->i915->irq_lock);
-	}
+	spin_lock(&engine->i915->irq_lock);
+	engine->irq_disable(engine);
+	spin_unlock(&engine->i915->irq_lock);
 }
 
 void __intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine)
@@ -293,25 +295,16 @@ static bool __intel_breadcrumbs_enable_irq(struct intel_breadcrumbs *b)
 	if (b->irq_armed)
 		return false;
 
-	/* The breadcrumb irq will be disarmed on the interrupt after the
+	/*
+	 * The breadcrumb irq will be disarmed on the interrupt after the
 	 * waiters are signaled. This gives us a single interrupt window in
 	 * which we can add a new waiter and avoid the cost of re-enabling
 	 * the irq.
 	 */
 	b->irq_armed = true;
 
-	if (I915_SELFTEST_ONLY(b->mock)) {
-		/* For our mock objects we want to avoid interaction
-		 * with the real hardware (which is not set up). So
-		 * we simply pretend we have enabled the powerwell
-		 * and the irq, and leave it up to the mock
-		 * implementation to call intel_engine_wakeup()
-		 * itself when it wants to simulate a user interrupt,
-		 */
-		return true;
-	}
-
-	/* Since we are waiting on a request, the GPU should be busy
+	/*
+	 * Since we are waiting on a request, the GPU should be busy
 	 * and should have its own rpm reference. This is tracked
 	 * by i915->gt.awake, we can forgo holding our own wakref
 	 * for the interrupt as before i915->gt.awake is released (when
diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index e2f65c59d6e8..fc52737751e7 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -917,6 +917,9 @@ static bool ring_is_idle(struct intel_engine_cs *engine)
 	intel_wakeref_t wakeref;
 	bool idle = true;
 
+	if (I915_SELFTEST_ONLY(!engine->mmio_base))
+		return true;
+
 	/* If the whole device is asleep, the engine must be idle */
 	wakeref = intel_runtime_pm_get_if_in_use(dev_priv);
 	if (!wakeref)
@@ -955,9 +958,6 @@ bool intel_engine_is_idle(struct intel_engine_cs *engine)
 	if (!intel_engine_signaled(engine, intel_engine_last_submit(engine)))
 		return false;
 
-	if (I915_SELFTEST_ONLY(engine->breadcrumbs.mock))
-		return true;
-
 	/* Waiting to drain ELSP? */
 	if (READ_ONCE(engine->execlists.active)) {
 		struct tasklet_struct *t = &engine->execlists.tasklet;
@@ -983,10 +983,7 @@ bool intel_engine_is_idle(struct intel_engine_cs *engine)
 		return false;
 
 	/* Ring stopped? */
-	if (!ring_is_idle(engine))
-		return false;
-
-	return true;
+	return ring_is_idle(engine);
 }
 
 bool intel_engines_are_idle(struct drm_i915_private *dev_priv)
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 1adf9845710c..17e05d11ee34 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -397,7 +397,6 @@ struct intel_engine_cs {
 		unsigned int irq_count;
 
 		bool irq_armed : 1;
-		I915_SELFTEST_DECLARE(bool mock : 1);
 	} breadcrumbs;
 
 	struct {
diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
index 50e1a0b1af7e..9fe5b2c8f8d4 100644
--- a/drivers/gpu/drm/i915/selftests/mock_engine.c
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
@@ -201,7 +201,6 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
 	i915_timeline_set_subclass(&engine->base.timeline, TIMELINE_ENGINE);
 
 	intel_engine_init_breadcrumbs(&engine->base);
-	engine->base.breadcrumbs.mock = true; /* prevent touching HW for irqs */
 
 	/* fake hw queue */
 	spin_lock_init(&engine->hw_lock);
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 10/23] drm/i915/selftests: Allocate mock ring/timeline per context
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (8 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 09/23] drm/i915: Use b->irq_enable() as predicate for mock engine Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 14:34 ` [PATCH 11/23] drm/i915/selftests: Make evict tolerant of foreign objects Chris Wilson
                   ` (17 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

To correctly simulate preemption between contexts, we need independent
timelines along each context. Make it so.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/selftests/mock_engine.c | 90 ++++++++++----------
 1 file changed, 47 insertions(+), 43 deletions(-)

diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
index 9fe5b2c8f8d4..8b8d51af7d6a 100644
--- a/drivers/gpu/drm/i915/selftests/mock_engine.c
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
@@ -30,6 +30,36 @@ struct mock_ring {
 	struct i915_timeline timeline;
 };
 
+static struct intel_ring *mock_ring(struct intel_engine_cs *engine)
+{
+	const unsigned long sz = PAGE_SIZE / 2;
+	struct mock_ring *ring;
+
+	ring = kzalloc(sizeof(*ring) + sz, GFP_KERNEL);
+	if (!ring)
+		return NULL;
+
+	i915_timeline_init(engine->i915, &ring->timeline, engine->name);
+
+	ring->base.size = sz;
+	ring->base.effective_size = sz;
+	ring->base.vaddr = (void *)(ring + 1);
+	ring->base.timeline = &ring->timeline;
+
+	INIT_LIST_HEAD(&ring->base.request_list);
+	intel_ring_update_space(&ring->base);
+
+	return &ring->base;
+}
+
+static void mock_ring_free(struct intel_ring *base)
+{
+	struct mock_ring *ring = container_of(base, typeof(*ring), base);
+
+	i915_timeline_fini(&ring->timeline);
+	kfree(ring);
+}
+
 static struct mock_request *first_request(struct mock_engine *engine)
 {
 	return list_first_entry_or_null(&engine->hw_queue,
@@ -80,6 +110,9 @@ static void mock_context_unpin(struct intel_context *ce)
 static void mock_context_destroy(struct intel_context *ce)
 {
 	GEM_BUG_ON(ce->pin_count);
+
+	if (ce->ring)
+		mock_ring_free(ce->ring);
 }
 
 static const struct intel_context_ops mock_context_ops = {
@@ -93,13 +126,22 @@ mock_context_pin(struct intel_engine_cs *engine,
 {
 	struct intel_context *ce = to_intel_context(ctx, engine);
 
-	if (!ce->pin_count++) {
-		i915_gem_context_get(ctx);
-		ce->ring = engine->buffer;
-		ce->ops = &mock_context_ops;
+	if (ce->pin_count++)
+		return ce;
+
+	if (!ce->ring) {
+		ce->ring = mock_ring(engine);
+		if (!ce->ring)
+			goto err;
 	}
 
+	ce->ops = &mock_context_ops;
+	i915_gem_context_get(ctx);
 	return ce;
+
+err:
+	ce->pin_count = 0;
+	return ERR_PTR(-ENOMEM);
 }
 
 static int mock_request_alloc(struct i915_request *request)
@@ -143,36 +185,6 @@ static void mock_submit_request(struct i915_request *request)
 	spin_unlock_irq(&engine->hw_lock);
 }
 
-static struct intel_ring *mock_ring(struct intel_engine_cs *engine)
-{
-	const unsigned long sz = PAGE_SIZE / 2;
-	struct mock_ring *ring;
-
-	ring = kzalloc(sizeof(*ring) + sz, GFP_KERNEL);
-	if (!ring)
-		return NULL;
-
-	i915_timeline_init(engine->i915, &ring->timeline, engine->name);
-
-	ring->base.size = sz;
-	ring->base.effective_size = sz;
-	ring->base.vaddr = (void *)(ring + 1);
-	ring->base.timeline = &ring->timeline;
-
-	INIT_LIST_HEAD(&ring->base.request_list);
-	intel_ring_update_space(&ring->base);
-
-	return &ring->base;
-}
-
-static void mock_ring_free(struct intel_ring *base)
-{
-	struct mock_ring *ring = container_of(base, typeof(*ring), base);
-
-	i915_timeline_fini(&ring->timeline);
-	kfree(ring);
-}
-
 struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
 				    const char *name,
 				    int id)
@@ -207,17 +219,11 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
 	timer_setup(&engine->hw_delay, hw_delay_complete, 0);
 	INIT_LIST_HEAD(&engine->hw_queue);
 
-	engine->base.buffer = mock_ring(&engine->base);
-	if (!engine->base.buffer)
-		goto err_breadcrumbs;
-
 	if (IS_ERR(intel_context_pin(i915->kernel_context, &engine->base)))
-		goto err_ring;
+		goto err_breadcrumbs;
 
 	return &engine->base;
 
-err_ring:
-	mock_ring_free(engine->base.buffer);
 err_breadcrumbs:
 	intel_engine_fini_breadcrumbs(&engine->base);
 	i915_timeline_fini(&engine->base.timeline);
@@ -260,8 +266,6 @@ void mock_engine_free(struct intel_engine_cs *engine)
 
 	__intel_context_unpin(engine->i915->kernel_context, engine);
 
-	mock_ring_free(engine->buffer);
-
 	intel_engine_fini_breadcrumbs(engine);
 	i915_timeline_fini(&engine->timeline);
 
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 11/23] drm/i915/selftests: Make evict tolerant of foreign objects
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (9 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 10/23] drm/i915/selftests: Allocate mock ring/timeline per context Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 17:29   ` Tvrtko Ursulin
  2019-01-17 14:34 ` [PATCH 12/23] drm/i915: Always allocate an object/vma for the HWSP Chris Wilson
                   ` (16 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

The evict selftests presumed that all objects in use had been allocated
by itself. This is a dubious claim and so instead of asserting complete
control over the object lists, take (temporary) ownership of them
instead.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 .../gpu/drm/i915/selftests/i915_gem_evict.c   | 64 +++++++++++++++----
 1 file changed, 53 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
index fb7df895afeb..c8deb961a020 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
@@ -31,30 +31,63 @@
 
 static int populate_ggtt(struct drm_i915_private *i915)
 {
-	struct drm_i915_gem_object *obj;
+	struct drm_i915_gem_object *obj, *on;
+	unsigned long expected_unbound, expected_bound;
+	unsigned long unbound, bound, count;
 	u64 size;
+	int err;
+
+	expected_unbound = 0;
+	list_for_each_entry(obj, &i915->mm.unbound_list, mm.link) {
+		i915_gem_object_get(obj);
+		expected_unbound++;
+	}
+
+	expected_bound = 0;
+	list_for_each_entry(obj, &i915->mm.bound_list, mm.link) {
+		i915_gem_object_get(obj);
+		expected_bound++;
+	}
 
+	count = 0;
 	for (size = 0;
 	     size + I915_GTT_PAGE_SIZE <= i915->ggtt.vm.total;
 	     size += I915_GTT_PAGE_SIZE) {
 		struct i915_vma *vma;
 
 		obj = i915_gem_object_create_internal(i915, I915_GTT_PAGE_SIZE);
-		if (IS_ERR(obj))
-			return PTR_ERR(obj);
+		if (IS_ERR(obj)) {
+			err = PTR_ERR(obj);
+			goto cleanup;
+		}
 
 		vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
-		if (IS_ERR(vma))
-			return PTR_ERR(vma);
+		if (IS_ERR(vma)) {
+			err = PTR_ERR(vma);
+			goto cleanup;
+		}
+
+		count++;
 	}
 
-	if (!list_empty(&i915->mm.unbound_list)) {
-		size = 0;
-		list_for_each_entry(obj, &i915->mm.unbound_list, mm.link)
-			size++;
+	unbound = 0;
+	list_for_each_entry(obj, &i915->mm.unbound_list, mm.link)
+		unbound++;
+	if (unbound != expected_unbound) {
+		pr_err("%s: Found %lu objects unbound, expected %lu!\n",
+		       __func__, unbound, expected_unbound);
+		err = -EINVAL;
+		goto cleanup;
+	}
 
-		pr_err("Found %lld objects unbound!\n", size);
-		return -EINVAL;
+	bound = 0;
+	list_for_each_entry(obj, &i915->mm.bound_list, mm.link)
+		bound++;
+	if (bound != expected_bound + count) {
+		pr_err("%s: Found %lu objects bound, expected %lu!\n",
+		       __func__, bound, expected_bound + count);
+		err = -EINVAL;
+		goto cleanup;
 	}
 
 	if (list_empty(&i915->ggtt.vm.bound_list)) {
@@ -63,6 +96,15 @@ static int populate_ggtt(struct drm_i915_private *i915)
 	}
 
 	return 0;
+
+cleanup:
+	list_for_each_entry_safe(obj, on, &i915->mm.unbound_list, mm.link)
+		i915_gem_object_put(obj);
+
+	list_for_each_entry_safe(obj, on, &i915->mm.bound_list, mm.link)
+		i915_gem_object_put(obj);
+
+	return err;
 }
 
 static void unpin_ggtt(struct drm_i915_private *i915)
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 12/23] drm/i915: Always allocate an object/vma for the HWSP
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (10 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 11/23] drm/i915/selftests: Make evict tolerant of foreign objects Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 14:34 ` [PATCH 13/23] drm/i915: Move list of timelines under its own lock Chris Wilson
                   ` (15 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx; +Cc: Matthew Auld

Currently we only allocate an object and vma if we are using a GGTT
virtual HWSP, and a plain struct page for a physical HWSP. For
convenience later on with global timelines, it will be useful to always
have the status page being tracked by a struct i915_vma. Make it so.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
---
 drivers/gpu/drm/i915/intel_engine_cs.c       | 109 ++++++++++---------
 drivers/gpu/drm/i915/intel_guc_submission.c  |   5 +
 drivers/gpu/drm/i915/intel_lrc.c             |  11 +-
 drivers/gpu/drm/i915/intel_ringbuffer.c      |  20 +++-
 drivers/gpu/drm/i915/intel_ringbuffer.h      |  23 +---
 drivers/gpu/drm/i915/selftests/mock_engine.c |   2 +-
 6 files changed, 90 insertions(+), 80 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index fc52737751e7..4b4b7358c482 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -506,27 +506,61 @@ void intel_engine_setup_common(struct intel_engine_cs *engine)
 
 static void cleanup_status_page(struct intel_engine_cs *engine)
 {
+	struct i915_vma *vma;
+
 	/* Prevent writes into HWSP after returning the page to the system */
 	intel_engine_set_hwsp_writemask(engine, ~0u);
 
-	if (HWS_NEEDS_PHYSICAL(engine->i915)) {
-		void *addr = fetch_and_zero(&engine->status_page.page_addr);
+	vma = fetch_and_zero(&engine->status_page.vma);
+	if (!vma)
+		return;
 
-		__free_page(virt_to_page(addr));
-	}
+	if (!HWS_NEEDS_PHYSICAL(engine->i915))
+		i915_vma_unpin(vma);
+
+	i915_gem_object_unpin_map(vma->obj);
+	__i915_gem_object_release_unless_active(vma->obj);
+}
+
+static int pin_ggtt_status_page(struct intel_engine_cs *engine,
+				struct i915_vma *vma)
+{
+	unsigned int flags;
+
+	flags = PIN_GLOBAL;
+	if (!HAS_LLC(engine->i915))
+		/*
+		 * On g33, we cannot place HWS above 256MiB, so
+		 * restrict its pinning to the low mappable arena.
+		 * Though this restriction is not documented for
+		 * gen4, gen5, or byt, they also behave similarly
+		 * and hang if the HWS is placed at the top of the
+		 * GTT. To generalise, it appears that all !llc
+		 * platforms have issues with us placing the HWS
+		 * above the mappable region (even though we never
+		 * actually map it).
+		 */
+		flags |= PIN_MAPPABLE;
+	else
+		flags |= PIN_HIGH;
 
-	i915_vma_unpin_and_release(&engine->status_page.vma,
-				   I915_VMA_RELEASE_MAP);
+	return i915_vma_pin(vma, 0, 0, flags);
 }
 
 static int init_status_page(struct intel_engine_cs *engine)
 {
 	struct drm_i915_gem_object *obj;
 	struct i915_vma *vma;
-	unsigned int flags;
 	void *vaddr;
 	int ret;
 
+	/*
+	 * Though the HWS register does support 36bit addresses, historically
+	 * we have had hangs and corruption reported due to wild writes if
+	 * the HWS is placed above 4G. We only allow objects to be allocated
+	 * in GFP_DMA32 for i965, and no earlier physical address users had
+	 * access to more than 4G.
+	 */
 	obj = i915_gem_object_create_internal(engine->i915, PAGE_SIZE);
 	if (IS_ERR(obj)) {
 		DRM_ERROR("Failed to allocate status page\n");
@@ -543,61 +577,30 @@ static int init_status_page(struct intel_engine_cs *engine)
 		goto err;
 	}
 
-	flags = PIN_GLOBAL;
-	if (!HAS_LLC(engine->i915))
-		/* On g33, we cannot place HWS above 256MiB, so
-		 * restrict its pinning to the low mappable arena.
-		 * Though this restriction is not documented for
-		 * gen4, gen5, or byt, they also behave similarly
-		 * and hang if the HWS is placed at the top of the
-		 * GTT. To generalise, it appears that all !llc
-		 * platforms have issues with us placing the HWS
-		 * above the mappable region (even though we never
-		 * actually map it).
-		 */
-		flags |= PIN_MAPPABLE;
-	else
-		flags |= PIN_HIGH;
-	ret = i915_vma_pin(vma, 0, 0, flags);
-	if (ret)
-		goto err;
-
 	vaddr = i915_gem_object_pin_map(obj, I915_MAP_WB);
 	if (IS_ERR(vaddr)) {
 		ret = PTR_ERR(vaddr);
-		goto err_unpin;
+		goto err;
 	}
 
+	engine->status_page.addr = memset(vaddr, 0, PAGE_SIZE);
 	engine->status_page.vma = vma;
-	engine->status_page.ggtt_offset = i915_ggtt_offset(vma);
-	engine->status_page.page_addr = memset(vaddr, 0, PAGE_SIZE);
+
+	if (!HWS_NEEDS_PHYSICAL(engine->i915)) {
+		ret = pin_ggtt_status_page(engine, vma);
+		if (ret)
+			goto err_unpin;
+	}
+
 	return 0;
 
 err_unpin:
-	i915_vma_unpin(vma);
+	i915_gem_object_unpin_map(obj);
 err:
 	i915_gem_object_put(obj);
 	return ret;
 }
 
-static int init_phys_status_page(struct intel_engine_cs *engine)
-{
-	struct page *page;
-
-	/*
-	 * Though the HWS register does support 36bit addresses, historically
-	 * we have had hangs and corruption reported due to wild writes if
-	 * the HWS is placed above 4G.
-	 */
-	page = alloc_page(GFP_KERNEL | __GFP_DMA32 | __GFP_ZERO);
-	if (!page)
-		return -ENOMEM;
-
-	engine->status_page.page_addr = page_address(page);
-
-	return 0;
-}
-
 static void __intel_context_unpin(struct i915_gem_context *ctx,
 				  struct intel_engine_cs *engine)
 {
@@ -650,10 +653,7 @@ int intel_engine_init_common(struct intel_engine_cs *engine)
 	if (ret)
 		goto err_unpin_preempt;
 
-	if (HWS_NEEDS_PHYSICAL(i915))
-		ret = init_phys_status_page(engine);
-	else
-		ret = init_status_page(engine);
+	ret = init_status_page(engine);
 	if (ret)
 		goto err_breadcrumbs;
 
@@ -1318,7 +1318,8 @@ static void intel_engine_print_registers(const struct intel_engine_cs *engine,
 	}
 
 	if (HAS_EXECLISTS(dev_priv)) {
-		const u32 *hws = &engine->status_page.page_addr[I915_HWS_CSB_BUF0_INDEX];
+		const u32 *hws =
+			&engine->status_page.addr[I915_HWS_CSB_BUF0_INDEX];
 		unsigned int idx;
 		u8 read, write;
 
@@ -1501,7 +1502,7 @@ void intel_engine_dump(struct intel_engine_cs *engine,
 	spin_unlock_irqrestore(&b->rb_lock, flags);
 
 	drm_printf(m, "HWSP:\n");
-	hexdump(m, engine->status_page.page_addr, PAGE_SIZE);
+	hexdump(m, engine->status_page.addr, PAGE_SIZE);
 
 	drm_printf(m, "Idle? %s\n", yesno(intel_engine_is_idle(engine)));
 }
diff --git a/drivers/gpu/drm/i915/intel_guc_submission.c b/drivers/gpu/drm/i915/intel_guc_submission.c
index 7217c7e3ee8d..b044162a41d3 100644
--- a/drivers/gpu/drm/i915/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/intel_guc_submission.c
@@ -81,6 +81,11 @@
  *
  */
 
+static inline u32 intel_hws_preempt_done_address(struct intel_engine_cs *engine)
+{
+	return i915_ggtt_offset(engine->status_page.vma) + I915_GEM_HWS_PREEMPT_ADDR;
+}
+
 static inline struct i915_priolist *to_priolist(struct rb_node *rb)
 {
 	return rb_entry(rb, struct i915_priolist, node);
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 7b56f2f17203..edb26f69d864 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -172,6 +172,11 @@ static void execlists_init_reg_state(u32 *reg_state,
 				     struct intel_engine_cs *engine,
 				     struct intel_ring *ring);
 
+static inline u32 intel_hws_seqno_address(struct intel_engine_cs *engine)
+{
+	return i915_ggtt_offset(engine->status_page.vma) + I915_GEM_HWS_INDEX_ADDR;
+}
+
 static inline struct i915_priolist *to_priolist(struct rb_node *rb)
 {
 	return rb_entry(rb, struct i915_priolist, node);
@@ -1679,7 +1684,7 @@ static void enable_execlists(struct intel_engine_cs *engine)
 		   _MASKED_BIT_DISABLE(STOP_RING));
 
 	I915_WRITE(RING_HWS_PGA(engine->mmio_base),
-		   engine->status_page.ggtt_offset);
+		   i915_ggtt_offset(engine->status_page.vma));
 	POSTING_READ(RING_HWS_PGA(engine->mmio_base));
 }
 
@@ -2226,10 +2231,10 @@ static int logical_ring_init(struct intel_engine_cs *engine)
 	}
 
 	execlists->csb_status =
-		&engine->status_page.page_addr[I915_HWS_CSB_BUF0_INDEX];
+		&engine->status_page.addr[I915_HWS_CSB_BUF0_INDEX];
 
 	execlists->csb_write =
-		&engine->status_page.page_addr[intel_hws_csb_write_index(i915)];
+		&engine->status_page.addr[intel_hws_csb_write_index(i915)];
 
 	reset_csb_pointers(execlists);
 
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 662907e1a286..d72012b42f20 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -43,6 +43,11 @@
  */
 #define LEGACY_REQUEST_SIZE 200
 
+static inline u32 intel_hws_seqno_address(struct intel_engine_cs *engine)
+{
+	return i915_ggtt_offset(engine->status_page.vma) + I915_GEM_HWS_INDEX_ADDR;
+}
+
 static unsigned int __intel_ring_space(unsigned int head,
 				       unsigned int tail,
 				       unsigned int size)
@@ -499,12 +504,17 @@ static void set_hws_pga(struct intel_engine_cs *engine, phys_addr_t phys)
 	I915_WRITE(HWS_PGA, addr);
 }
 
-static void ring_setup_phys_status_page(struct intel_engine_cs *engine)
+static struct page *status_page(struct intel_engine_cs *engine)
 {
-	struct page *page = virt_to_page(engine->status_page.page_addr);
-	phys_addr_t phys = PFN_PHYS(page_to_pfn(page));
+	struct drm_i915_gem_object *obj = engine->status_page.vma->obj;
 
-	set_hws_pga(engine, phys);
+	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
+	return sg_page(obj->mm.pages->sgl);
+}
+
+static void ring_setup_phys_status_page(struct intel_engine_cs *engine)
+{
+	set_hws_pga(engine, PFN_PHYS(page_to_pfn(status_page(engine))));
 	set_hwstam(engine, ~0u);
 }
 
@@ -571,7 +581,7 @@ static void flush_cs_tlb(struct intel_engine_cs *engine)
 
 static void ring_setup_status_page(struct intel_engine_cs *engine)
 {
-	set_hwsp(engine, engine->status_page.ggtt_offset);
+	set_hwsp(engine, i915_ggtt_offset(engine->status_page.vma));
 	set_hwstam(engine, ~0u);
 
 	flush_cs_tlb(engine);
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 17e05d11ee34..9972c9016445 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -32,8 +32,7 @@ struct i915_sched_attr;
 
 struct intel_hw_status_page {
 	struct i915_vma *vma;
-	u32 *page_addr;
-	u32 ggtt_offset;
+	u32 *addr;
 };
 
 #define I915_READ_TAIL(engine) I915_READ(RING_TAIL((engine)->mmio_base))
@@ -675,7 +674,7 @@ static inline u32
 intel_read_status_page(const struct intel_engine_cs *engine, int reg)
 {
 	/* Ensure that the compiler doesn't optimize away the load. */
-	return READ_ONCE(engine->status_page.page_addr[reg]);
+	return READ_ONCE(engine->status_page.addr[reg]);
 }
 
 static inline void
@@ -688,12 +687,12 @@ intel_write_status_page(struct intel_engine_cs *engine, int reg, u32 value)
 	 */
 	if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
 		mb();
-		clflush(&engine->status_page.page_addr[reg]);
-		engine->status_page.page_addr[reg] = value;
-		clflush(&engine->status_page.page_addr[reg]);
+		clflush(&engine->status_page.addr[reg]);
+		engine->status_page.addr[reg] = value;
+		clflush(&engine->status_page.addr[reg]);
 		mb();
 	} else {
-		WRITE_ONCE(engine->status_page.page_addr[reg], value);
+		WRITE_ONCE(engine->status_page.addr[reg], value);
 	}
 }
 
@@ -881,16 +880,6 @@ static inline bool intel_engine_has_started(struct intel_engine_cs *engine,
 void intel_engine_get_instdone(struct intel_engine_cs *engine,
 			       struct intel_instdone *instdone);
 
-static inline u32 intel_hws_seqno_address(struct intel_engine_cs *engine)
-{
-	return engine->status_page.ggtt_offset + I915_GEM_HWS_INDEX_ADDR;
-}
-
-static inline u32 intel_hws_preempt_done_address(struct intel_engine_cs *engine)
-{
-	return engine->status_page.ggtt_offset + I915_GEM_HWS_PREEMPT_ADDR;
-}
-
 /* intel_breadcrumbs.c -- user interrupt bottom-half for waiters */
 int intel_engine_init_breadcrumbs(struct intel_engine_cs *engine);
 
diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
index 8b8d51af7d6a..968a7e139a67 100644
--- a/drivers/gpu/drm/i915/selftests/mock_engine.c
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
@@ -201,7 +201,7 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
 	engine->base.i915 = i915;
 	snprintf(engine->base.name, sizeof(engine->base.name), "%s", name);
 	engine->base.id = id;
-	engine->base.status_page.page_addr = (void *)(engine + 1);
+	engine->base.status_page.addr = (void *)(engine + 1);
 
 	engine->base.context_pin = mock_context_pin;
 	engine->base.request_alloc = mock_request_alloc;
-- 
2.20.1

_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 13/23] drm/i915: Move list of timelines under its own lock
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (11 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 12/23] drm/i915: Always allocate an object/vma for the HWSP Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 17:54   ` Tvrtko Ursulin
  2019-01-17 14:34 ` [PATCH 14/23] drm/i915: Introduce concept of per-timeline (context) HWSP Chris Wilson
                   ` (14 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Currently, the list of timelines is serialised by the struct_mutex, but
to alleviate difficulties with using that mutex in future, move the
list management under its own dedicated mutex.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_drv.h               |  5 +-
 drivers/gpu/drm/i915/i915_gem.c               | 89 +++++++++----------
 drivers/gpu/drm/i915/i915_reset.c             |  8 +-
 drivers/gpu/drm/i915/i915_timeline.c          | 38 ++++++--
 drivers/gpu/drm/i915/i915_timeline.h          |  3 +
 drivers/gpu/drm/i915/i915_vma.c               |  6 ++
 .../gpu/drm/i915/selftests/mock_gem_device.c  |  7 +-
 .../gpu/drm/i915/selftests/mock_timeline.c    |  3 +-
 8 files changed, 101 insertions(+), 58 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 94680b15bed0..3913900600b7 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1975,7 +1975,10 @@ struct drm_i915_private {
 		void (*resume)(struct drm_i915_private *);
 		void (*cleanup_engine)(struct intel_engine_cs *engine);
 
-		struct list_head timelines;
+		struct i915_gt_timelines {
+			struct mutex mutex; /* protects list, tainted by GPU */
+			struct list_head list;
+		} timelines;
 
 		struct list_head active_rings;
 		struct list_head closed_vma;
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 15acd052da46..3c6091021290 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3222,33 +3222,6 @@ i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
 	return ret;
 }
 
-static long wait_for_timeline(struct i915_timeline *tl,
-			      unsigned int flags, long timeout)
-{
-	struct i915_request *rq;
-
-	rq = i915_gem_active_get_unlocked(&tl->last_request);
-	if (!rq)
-		return timeout;
-
-	/*
-	 * "Race-to-idle".
-	 *
-	 * Switching to the kernel context is often used a synchronous
-	 * step prior to idling, e.g. in suspend for flushing all
-	 * current operations to memory before sleeping. These we
-	 * want to complete as quickly as possible to avoid prolonged
-	 * stalls, so allow the gpu to boost to maximum clocks.
-	 */
-	if (flags & I915_WAIT_FOR_IDLE_BOOST)
-		gen6_rps_boost(rq, NULL);
-
-	timeout = i915_request_wait(rq, flags, timeout);
-	i915_request_put(rq);
-
-	return timeout;
-}
-
 static int wait_for_engines(struct drm_i915_private *i915)
 {
 	if (wait_for(intel_engines_are_idle(i915), I915_IDLE_ENGINES_TIMEOUT)) {
@@ -3265,6 +3238,8 @@ static int wait_for_engines(struct drm_i915_private *i915)
 int i915_gem_wait_for_idle(struct drm_i915_private *i915,
 			   unsigned int flags, long timeout)
 {
+	struct i915_timeline *tl;
+
 	GEM_TRACE("flags=%x (%s), timeout=%ld%s\n",
 		  flags, flags & I915_WAIT_LOCKED ? "locked" : "unlocked",
 		  timeout, timeout == MAX_SCHEDULE_TIMEOUT ? " (forever)" : "");
@@ -3273,17 +3248,45 @@ int i915_gem_wait_for_idle(struct drm_i915_private *i915,
 	if (!READ_ONCE(i915->gt.awake))
 		return 0;
 
+	mutex_lock(&i915->gt.timelines.mutex);
+	list_for_each_entry(tl, &i915->gt.timelines.list, link) {
+		struct i915_request *rq;
+
+		rq = i915_gem_active_get_unlocked(&tl->last_request);
+		if (!rq)
+			continue;
+
+		mutex_unlock(&i915->gt.timelines.mutex);
+
+		/*
+		 * "Race-to-idle".
+		 *
+		 * Switching to the kernel context is often used a synchronous
+		 * step prior to idling, e.g. in suspend for flushing all
+		 * current operations to memory before sleeping. These we
+		 * want to complete as quickly as possible to avoid prolonged
+		 * stalls, so allow the gpu to boost to maximum clocks.
+		 */
+		if (flags & I915_WAIT_FOR_IDLE_BOOST)
+			gen6_rps_boost(rq, NULL);
+
+		timeout = i915_request_wait(rq, flags, timeout);
+		i915_request_put(rq);
+		if (timeout < 0)
+			return timeout;
+
+		mutex_lock(&i915->gt.timelines.mutex);
+
+		/* restart after dropping the lock */
+		tl = list_entry(&i915->gt.timelines.list, typeof(*tl), link);
+	}
+	mutex_unlock(&i915->gt.timelines.mutex);
+
 	if (flags & I915_WAIT_LOCKED) {
-		struct i915_timeline *tl;
 		int err;
 
 		lockdep_assert_held(&i915->drm.struct_mutex);
 
-		list_for_each_entry(tl, &i915->gt.timelines, link) {
-			timeout = wait_for_timeline(tl, flags, timeout);
-			if (timeout < 0)
-				return timeout;
-		}
 		if (GEM_SHOW_DEBUG() && !timeout) {
 			/* Presume that timeout was non-zero to begin with! */
 			dev_warn(&i915->drm.pdev->dev,
@@ -3297,17 +3300,6 @@ int i915_gem_wait_for_idle(struct drm_i915_private *i915,
 
 		i915_retire_requests(i915);
 		GEM_BUG_ON(i915->gt.active_requests);
-	} else {
-		struct intel_engine_cs *engine;
-		enum intel_engine_id id;
-
-		for_each_engine(engine, i915, id) {
-			struct i915_timeline *tl = &engine->timeline;
-
-			timeout = wait_for_timeline(tl, flags, timeout);
-			if (timeout < 0)
-				return timeout;
-		}
 	}
 
 	return 0;
@@ -5008,6 +5000,8 @@ int i915_gem_init(struct drm_i915_private *dev_priv)
 		dev_priv->gt.cleanup_engine = intel_engine_cleanup;
 	}
 
+	i915_timelines_init(dev_priv);
+
 	ret = i915_gem_init_userptr(dev_priv);
 	if (ret)
 		return ret;
@@ -5130,8 +5124,10 @@ int i915_gem_init(struct drm_i915_private *dev_priv)
 err_uc_misc:
 	intel_uc_fini_misc(dev_priv);
 
-	if (ret != -EIO)
+	if (ret != -EIO) {
 		i915_gem_cleanup_userptr(dev_priv);
+		i915_timelines_fini(dev_priv);
+	}
 
 	if (ret == -EIO) {
 		mutex_lock(&dev_priv->drm.struct_mutex);
@@ -5182,6 +5178,7 @@ void i915_gem_fini(struct drm_i915_private *dev_priv)
 
 	intel_uc_fini_misc(dev_priv);
 	i915_gem_cleanup_userptr(dev_priv);
+	i915_timelines_fini(dev_priv);
 
 	i915_gem_drain_freed_objects(dev_priv);
 
@@ -5284,7 +5281,6 @@ int i915_gem_init_early(struct drm_i915_private *dev_priv)
 	if (!dev_priv->priorities)
 		goto err_dependencies;
 
-	INIT_LIST_HEAD(&dev_priv->gt.timelines);
 	INIT_LIST_HEAD(&dev_priv->gt.active_rings);
 	INIT_LIST_HEAD(&dev_priv->gt.closed_vma);
 
@@ -5328,7 +5324,6 @@ void i915_gem_cleanup_early(struct drm_i915_private *dev_priv)
 	GEM_BUG_ON(!llist_empty(&dev_priv->mm.free_list));
 	GEM_BUG_ON(atomic_read(&dev_priv->mm.free_count));
 	WARN_ON(dev_priv->mm.object_count);
-	WARN_ON(!list_empty(&dev_priv->gt.timelines));
 
 	kmem_cache_destroy(dev_priv->priorities);
 	kmem_cache_destroy(dev_priv->dependencies);
diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index d44b095e2860..12e5a2bc825c 100644
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -850,7 +850,8 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 	 *
 	 * No more can be submitted until we reset the wedged bit.
 	 */
-	list_for_each_entry(tl, &i915->gt.timelines, link) {
+	mutex_lock(&i915->gt.timelines.mutex);
+	list_for_each_entry(tl, &i915->gt.timelines.list, link) {
 		struct i915_request *rq;
 		long timeout;
 
@@ -872,9 +873,12 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
 		timeout = dma_fence_default_wait(&rq->fence, true,
 						 MAX_SCHEDULE_TIMEOUT);
 		i915_request_put(rq);
-		if (timeout < 0)
+		if (timeout < 0) {
+			mutex_unlock(&i915->gt.timelines.mutex);
 			goto unlock;
+		}
 	}
+	mutex_unlock(&i915->gt.timelines.mutex);
 
 	intel_engines_sanitize(i915, false);
 
diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
index 4667cc08c416..84550f17d3df 100644
--- a/drivers/gpu/drm/i915/i915_timeline.c
+++ b/drivers/gpu/drm/i915/i915_timeline.c
@@ -13,7 +13,7 @@ void i915_timeline_init(struct drm_i915_private *i915,
 			struct i915_timeline *timeline,
 			const char *name)
 {
-	lockdep_assert_held(&i915->drm.struct_mutex);
+	struct i915_gt_timelines *gt = &i915->gt.timelines;
 
 	/*
 	 * Ideally we want a set of engines on a single leaf as we expect
@@ -23,9 +23,12 @@ void i915_timeline_init(struct drm_i915_private *i915,
 	 */
 	BUILD_BUG_ON(KSYNCMAP < I915_NUM_ENGINES);
 
+	timeline->i915 = i915;
 	timeline->name = name;
 
-	list_add(&timeline->link, &i915->gt.timelines);
+	mutex_lock(&gt->mutex);
+	list_add(&timeline->link, &gt->list);
+	mutex_unlock(&gt->mutex);
 
 	/* Called during early_init before we know how many engines there are */
 
@@ -39,6 +42,17 @@ void i915_timeline_init(struct drm_i915_private *i915,
 	i915_syncmap_init(&timeline->sync);
 }
 
+void i915_timelines_init(struct drm_i915_private *i915)
+{
+	struct i915_gt_timelines *gt = &i915->gt.timelines;
+
+	mutex_init(&gt->mutex);
+	INIT_LIST_HEAD(&gt->list);
+
+	/* via i915_gem_wait_for_idle() */
+	i915_gem_shrinker_taints_mutex(i915, &gt->mutex);
+}
+
 /**
  * i915_timelines_park - called when the driver idles
  * @i915: the drm_i915_private device
@@ -51,11 +65,11 @@ void i915_timeline_init(struct drm_i915_private *i915,
  */
 void i915_timelines_park(struct drm_i915_private *i915)
 {
+	struct i915_gt_timelines *gt = &i915->gt.timelines;
 	struct i915_timeline *timeline;
 
-	lockdep_assert_held(&i915->drm.struct_mutex);
-
-	list_for_each_entry(timeline, &i915->gt.timelines, link) {
+	mutex_lock(&gt->mutex);
+	list_for_each_entry(timeline, &gt->list, link) {
 		/*
 		 * All known fences are completed so we can scrap
 		 * the current sync point tracking and start afresh,
@@ -64,15 +78,20 @@ void i915_timelines_park(struct drm_i915_private *i915)
 		 */
 		i915_syncmap_free(&timeline->sync);
 	}
+	mutex_unlock(&gt->mutex);
 }
 
 void i915_timeline_fini(struct i915_timeline *timeline)
 {
+	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
+
 	GEM_BUG_ON(!list_empty(&timeline->requests));
 
 	i915_syncmap_free(&timeline->sync);
 
+	mutex_lock(&gt->mutex);
 	list_del(&timeline->link);
+	mutex_unlock(&gt->mutex);
 }
 
 struct i915_timeline *
@@ -99,6 +118,15 @@ void __i915_timeline_free(struct kref *kref)
 	kfree(timeline);
 }
 
+void i915_timelines_fini(struct drm_i915_private *i915)
+{
+	struct i915_gt_timelines *gt = &i915->gt.timelines;
+
+	GEM_BUG_ON(!list_empty(&gt->list));
+
+	mutex_destroy(&gt->mutex);
+}
+
 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
 #include "selftests/mock_timeline.c"
 #include "selftests/i915_timeline.c"
diff --git a/drivers/gpu/drm/i915/i915_timeline.h b/drivers/gpu/drm/i915/i915_timeline.h
index 38c1e15e927a..87ad2dd31c20 100644
--- a/drivers/gpu/drm/i915/i915_timeline.h
+++ b/drivers/gpu/drm/i915/i915_timeline.h
@@ -66,6 +66,7 @@ struct i915_timeline {
 
 	struct list_head link;
 	const char *name;
+	struct drm_i915_private *i915;
 
 	struct kref kref;
 };
@@ -134,6 +135,8 @@ static inline bool i915_timeline_sync_is_later(struct i915_timeline *tl,
 	return __i915_timeline_sync_is_later(tl, fence->context, fence->seqno);
 }
 
+void i915_timelines_init(struct drm_i915_private *i915);
 void i915_timelines_park(struct drm_i915_private *i915);
+void i915_timelines_fini(struct drm_i915_private *i915);
 
 #endif
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 3a680fe2bb8b..d83b8ad5f859 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -201,6 +201,11 @@ vma_create(struct drm_i915_gem_object *obj,
 		rb = *p;
 		pos = rb_entry(rb, struct i915_vma, obj_node);
 
+		/*
+		 * If the view already exists in the tree, another thread
+		 * already created a matching vma, so return the older instance
+		 * and dispose of ours.
+		 */
 		cmp = i915_vma_compare(pos, vm, view);
 		if (cmp == 0) {
 			spin_unlock(&obj->vma.lock);
@@ -294,6 +299,7 @@ i915_vma_instance(struct drm_i915_gem_object *obj,
 	vma = vma_lookup(obj, vm, view);
 	spin_unlock(&obj->vma.lock);
 
+	/* vma_create() will resolve the race if another creates the vma */
 	if (unlikely(!vma))
 		vma = vma_create(obj, vm, view);
 
diff --git a/drivers/gpu/drm/i915/selftests/mock_gem_device.c b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
index 888c6978bc54..41ae502361d7 100644
--- a/drivers/gpu/drm/i915/selftests/mock_gem_device.c
+++ b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
@@ -68,13 +68,14 @@ static void mock_device_release(struct drm_device *dev)
 	i915_gem_contexts_fini(i915);
 	mutex_unlock(&i915->drm.struct_mutex);
 
+	i915_timelines_fini(i915);
+
 	drain_workqueue(i915->wq);
 	i915_gem_drain_freed_objects(i915);
 
 	mutex_lock(&i915->drm.struct_mutex);
 	mock_fini_ggtt(i915);
 	mutex_unlock(&i915->drm.struct_mutex);
-	WARN_ON(!list_empty(&i915->gt.timelines));
 
 	destroy_workqueue(i915->wq);
 
@@ -226,7 +227,8 @@ struct drm_i915_private *mock_gem_device(void)
 	if (!i915->priorities)
 		goto err_dependencies;
 
-	INIT_LIST_HEAD(&i915->gt.timelines);
+	i915_timelines_init(i915);
+
 	INIT_LIST_HEAD(&i915->gt.active_rings);
 	INIT_LIST_HEAD(&i915->gt.closed_vma);
 
@@ -253,6 +255,7 @@ struct drm_i915_private *mock_gem_device(void)
 	i915_gem_contexts_fini(i915);
 err_unlock:
 	mutex_unlock(&i915->drm.struct_mutex);
+	i915_timelines_fini(i915);
 	kmem_cache_destroy(i915->priorities);
 err_dependencies:
 	kmem_cache_destroy(i915->dependencies);
diff --git a/drivers/gpu/drm/i915/selftests/mock_timeline.c b/drivers/gpu/drm/i915/selftests/mock_timeline.c
index dcf3b16f5a07..cf39ccd9fc05 100644
--- a/drivers/gpu/drm/i915/selftests/mock_timeline.c
+++ b/drivers/gpu/drm/i915/selftests/mock_timeline.c
@@ -10,6 +10,7 @@
 
 void mock_timeline_init(struct i915_timeline *timeline, u64 context)
 {
+	timeline->i915 = NULL;
 	timeline->fence_context = context;
 
 	spin_lock_init(&timeline->lock);
@@ -24,5 +25,5 @@ void mock_timeline_init(struct i915_timeline *timeline, u64 context)
 
 void mock_timeline_fini(struct i915_timeline *timeline)
 {
-	i915_timeline_fini(timeline);
+	i915_syncmap_free(&timeline->sync);
 }
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 14/23] drm/i915: Introduce concept of per-timeline (context) HWSP
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (12 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 13/23] drm/i915: Move list of timelines under its own lock Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-18 10:18   ` Tvrtko Ursulin
  2019-01-17 14:34 ` [PATCH 15/23] drm/i915: Enlarge vma->pin_count Chris Wilson
                   ` (13 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Supplement the per-engine HWSP with a per-timeline HWSP. That is a
per-request pointer through which we can check a local seqno,
abstracting away the presumption of a global seqno. In this first step,
we point each request back into the engine's HWSP so everything
continues to work with the global timeline.

v2: s/i915_request_hwsp/hwsp_seqno/ to emphasis that this is the current
HW value and that we are accessing it via i915_request merely as a
convenience.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_request.c | 16 +++++++++-----
 drivers/gpu/drm/i915/i915_request.h | 34 +++++++++++++++++++++++------
 drivers/gpu/drm/i915/intel_lrc.c    |  9 +++++---
 3 files changed, 44 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index fb723ed2f574..7d068c406a49 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -182,10 +182,11 @@ static void free_capture_list(struct i915_request *request)
 static void __retire_engine_request(struct intel_engine_cs *engine,
 				    struct i915_request *rq)
 {
-	GEM_TRACE("%s(%s) fence %llx:%lld, global=%d, current %d\n",
+	GEM_TRACE("%s(%s) fence %llx:%lld, global=%d, current %d:%d\n",
 		  __func__, engine->name,
 		  rq->fence.context, rq->fence.seqno,
 		  rq->global_seqno,
+		  hwsp_seqno(rq),
 		  intel_engine_get_seqno(engine));
 
 	GEM_BUG_ON(!i915_request_completed(rq));
@@ -244,10 +245,11 @@ static void i915_request_retire(struct i915_request *request)
 {
 	struct i915_gem_active *active, *next;
 
-	GEM_TRACE("%s fence %llx:%lld, global=%d, current %d\n",
+	GEM_TRACE("%s fence %llx:%lld, global=%d, current %d:%d\n",
 		  request->engine->name,
 		  request->fence.context, request->fence.seqno,
 		  request->global_seqno,
+		  hwsp_seqno(request),
 		  intel_engine_get_seqno(request->engine));
 
 	lockdep_assert_held(&request->i915->drm.struct_mutex);
@@ -307,10 +309,11 @@ void i915_request_retire_upto(struct i915_request *rq)
 	struct intel_ring *ring = rq->ring;
 	struct i915_request *tmp;
 
-	GEM_TRACE("%s fence %llx:%lld, global=%d, current %d\n",
+	GEM_TRACE("%s fence %llx:%lld, global=%d, current %d:%d\n",
 		  rq->engine->name,
 		  rq->fence.context, rq->fence.seqno,
 		  rq->global_seqno,
+		  hwsp_seqno(rq),
 		  intel_engine_get_seqno(rq->engine));
 
 	lockdep_assert_held(&rq->i915->drm.struct_mutex);
@@ -348,10 +351,11 @@ void __i915_request_submit(struct i915_request *request)
 	struct intel_engine_cs *engine = request->engine;
 	u32 seqno;
 
-	GEM_TRACE("%s fence %llx:%lld -> global=%d, current %d\n",
+	GEM_TRACE("%s fence %llx:%lld -> global=%d, current %d:%d\n",
 		  engine->name,
 		  request->fence.context, request->fence.seqno,
 		  engine->timeline.seqno + 1,
+		  hwsp_seqno(request),
 		  intel_engine_get_seqno(engine));
 
 	GEM_BUG_ON(!irqs_disabled());
@@ -398,10 +402,11 @@ void __i915_request_unsubmit(struct i915_request *request)
 {
 	struct intel_engine_cs *engine = request->engine;
 
-	GEM_TRACE("%s fence %llx:%lld <- global=%d, current %d\n",
+	GEM_TRACE("%s fence %llx:%lld <- global=%d, current %d:%d\n",
 		  engine->name,
 		  request->fence.context, request->fence.seqno,
 		  request->global_seqno,
+		  hwsp_seqno(request),
 		  intel_engine_get_seqno(engine));
 
 	GEM_BUG_ON(!irqs_disabled());
@@ -609,6 +614,7 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx)
 	rq->ring = ce->ring;
 	rq->timeline = ce->ring->timeline;
 	GEM_BUG_ON(rq->timeline == &engine->timeline);
+	rq->hwsp_seqno = &engine->status_page.addr[I915_GEM_HWS_INDEX];
 
 	spin_lock_init(&rq->lock);
 	dma_fence_init(&rq->fence,
diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h
index d014b0605445..4dd22dadf5ce 100644
--- a/drivers/gpu/drm/i915/i915_request.h
+++ b/drivers/gpu/drm/i915/i915_request.h
@@ -130,6 +130,13 @@ struct i915_request {
 	struct i915_sched_node sched;
 	struct i915_dependency dep;
 
+	/*
+	 * A convenience pointer to the current breadcrumb value stored in
+	 * the HW status page (or our timeline's local equivalent). The full
+	 * path would be rq->hw_context->ring->timeline->hwsp_seqno.
+	 */
+	const u32 *hwsp_seqno;
+
 	/**
 	 * GEM sequence number associated with this request on the
 	 * global execution timeline. It is zero when the request is not
@@ -280,11 +287,6 @@ long i915_request_wait(struct i915_request *rq,
 #define I915_WAIT_ALL		BIT(3) /* used by i915_gem_object_wait() */
 #define I915_WAIT_FOR_IDLE_BOOST BIT(4)
 
-static inline bool intel_engine_has_started(struct intel_engine_cs *engine,
-					    u32 seqno);
-static inline bool intel_engine_has_completed(struct intel_engine_cs *engine,
-					      u32 seqno);
-
 /**
  * Returns true if seq1 is later than seq2.
  */
@@ -293,6 +295,24 @@ static inline bool i915_seqno_passed(u32 seq1, u32 seq2)
 	return (s32)(seq1 - seq2) >= 0;
 }
 
+/**
+ * hwsp_seqno - the current breadcrumb value in the HW status page
+ * @rq: the request, to chase the relevant HW status page
+ *
+ * The emphasis in naming here is that hwsp_seqno() is not a property of the
+ * request, but an indication of the current HW state (associated with this
+ * request). Its value will change as the GPU executes more requests.
+ *
+ * Returns the current breadcrumb value in the associated HW status page (or
+ * the local timeline's equivalent) for this request. The request itself
+ * has the associated breadcrumb value of rq->fence.seqno, when the HW
+ * status page has that breadcrumb or later, this request is complete.
+ */
+static inline u32 hwsp_seqno(const struct i915_request *rq)
+{
+	return READ_ONCE(*rq->hwsp_seqno);
+}
+
 /**
  * i915_request_started - check if the request has begun being executed
  * @rq: the request
@@ -310,14 +330,14 @@ static inline bool i915_request_started(const struct i915_request *rq)
 	if (!seqno) /* not yet submitted to HW */
 		return false;
 
-	return intel_engine_has_started(rq->engine, seqno);
+	return i915_seqno_passed(hwsp_seqno(rq), seqno - 1);
 }
 
 static inline bool
 __i915_request_completed(const struct i915_request *rq, u32 seqno)
 {
 	GEM_BUG_ON(!seqno);
-	return intel_engine_has_completed(rq->engine, seqno) &&
+	return i915_seqno_passed(hwsp_seqno(rq), seqno) &&
 		seqno == i915_request_global_seqno(rq);
 }
 
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index edb26f69d864..4e942c403333 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -444,11 +444,12 @@ static void execlists_submit_ports(struct intel_engine_cs *engine)
 			desc = execlists_update_context(rq);
 			GEM_DEBUG_EXEC(port[n].context_id = upper_32_bits(desc));
 
-			GEM_TRACE("%s in[%d]:  ctx=%d.%d, global=%d (fence %llx:%lld) (current %d), prio=%d\n",
+			GEM_TRACE("%s in[%d]:  ctx=%d.%d, global=%d (fence %llx:%lld) (current %d:%d), prio=%d\n",
 				  engine->name, n,
 				  port[n].context_id, count,
 				  rq->global_seqno,
 				  rq->fence.context, rq->fence.seqno,
+				  hwsp_seqno(rq),
 				  intel_engine_get_seqno(engine),
 				  rq_prio(rq));
 		} else {
@@ -737,11 +738,12 @@ execlists_cancel_port_requests(struct intel_engine_execlists * const execlists)
 	while (num_ports-- && port_isset(port)) {
 		struct i915_request *rq = port_request(port);
 
-		GEM_TRACE("%s:port%u global=%d (fence %llx:%lld), (current %d)\n",
+		GEM_TRACE("%s:port%u global=%d (fence %llx:%lld), (current %d:%d)\n",
 			  rq->engine->name,
 			  (unsigned int)(port - execlists->port),
 			  rq->global_seqno,
 			  rq->fence.context, rq->fence.seqno,
+			  hwsp_seqno(rq),
 			  intel_engine_get_seqno(rq->engine));
 
 		GEM_BUG_ON(!execlists->active);
@@ -965,12 +967,13 @@ static void process_csb(struct intel_engine_cs *engine)
 						EXECLISTS_ACTIVE_USER));
 
 		rq = port_unpack(port, &count);
-		GEM_TRACE("%s out[0]: ctx=%d.%d, global=%d (fence %llx:%lld) (current %d), prio=%d\n",
+		GEM_TRACE("%s out[0]: ctx=%d.%d, global=%d (fence %llx:%lld) (current %d:%d), prio=%d\n",
 			  engine->name,
 			  port->context_id, count,
 			  rq ? rq->global_seqno : 0,
 			  rq ? rq->fence.context : 0,
 			  rq ? rq->fence.seqno : 0,
+			  rq ? hwsp_seqno(rq) : 0,
 			  intel_engine_get_seqno(engine),
 			  rq ? rq_prio(rq) : 0);
 
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 15/23] drm/i915: Enlarge vma->pin_count
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (13 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 14/23] drm/i915: Introduce concept of per-timeline (context) HWSP Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-17 14:34 ` [PATCH 16/23] drm/i915: Allocate a status page for each timeline Chris Wilson
                   ` (12 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Previously we only accommodated having a vma pinned by a small number of
users, with the maximum being pinned for use by the display engine. As
such, we used a small bitfield only large enough to allow the vma to
be pinned twice (for back/front buffers) in each scanout plane. Keeping
the maximum permissible pin_count small allows us to quickly catch a
potential leak. However, as we want to split a 4096B page into 64
different cachelines and pin each cacheline for use by a different
timeline, we will exceed the current maximum permissible vma->pin_count
and so time has come to enlarge it.

Whilst we are here, try to pull together the similar bits:

Address/layout specification:
 - bias, mappable, zone_4g: address limit specifiers
 - fixed: address override, limits still apply though
 - high: not strictly an address limit, but an address direction to search

Search controls:
 - nonblock, nonfault, noevict

v2: Rewrite the guideline comment on bit consumption.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: John Harrison <john.C.Harrison@intel.com>
---
 drivers/gpu/drm/i915/i915_gem_gtt.h | 26 ++++++++---------
 drivers/gpu/drm/i915/i915_vma.h     | 45 +++++++++++++++++++----------
 2 files changed, 42 insertions(+), 29 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index bd679c8c56dd..03ade71b8d9a 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -642,19 +642,19 @@ int i915_gem_gtt_insert(struct i915_address_space *vm,
 
 /* Flags used by pin/bind&friends. */
 #define PIN_NONBLOCK		BIT_ULL(0)
-#define PIN_MAPPABLE		BIT_ULL(1)
-#define PIN_ZONE_4G		BIT_ULL(2)
-#define PIN_NONFAULT		BIT_ULL(3)
-#define PIN_NOEVICT		BIT_ULL(4)
-
-#define PIN_MBZ			BIT_ULL(5) /* I915_VMA_PIN_OVERFLOW */
-#define PIN_GLOBAL		BIT_ULL(6) /* I915_VMA_GLOBAL_BIND */
-#define PIN_USER		BIT_ULL(7) /* I915_VMA_LOCAL_BIND */
-#define PIN_UPDATE		BIT_ULL(8)
-
-#define PIN_HIGH		BIT_ULL(9)
-#define PIN_OFFSET_BIAS		BIT_ULL(10)
-#define PIN_OFFSET_FIXED	BIT_ULL(11)
+#define PIN_NONFAULT		BIT_ULL(1)
+#define PIN_NOEVICT		BIT_ULL(2)
+#define PIN_MAPPABLE		BIT_ULL(3)
+#define PIN_ZONE_4G		BIT_ULL(4)
+#define PIN_HIGH		BIT_ULL(5)
+#define PIN_OFFSET_BIAS		BIT_ULL(6)
+#define PIN_OFFSET_FIXED	BIT_ULL(7)
+
+#define PIN_MBZ			BIT_ULL(8) /* I915_VMA_PIN_OVERFLOW */
+#define PIN_GLOBAL		BIT_ULL(9) /* I915_VMA_GLOBAL_BIND */
+#define PIN_USER		BIT_ULL(10) /* I915_VMA_LOCAL_BIND */
+#define PIN_UPDATE		BIT_ULL(11)
+
 #define PIN_OFFSET_MASK		(-I915_GTT_PAGE_SIZE)
 
 #endif
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 7252abc73d3e..5793abe509a2 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -71,29 +71,42 @@ struct i915_vma {
 	unsigned int open_count;
 	unsigned long flags;
 	/**
-	 * How many users have pinned this object in GTT space. The following
-	 * users can each hold at most one reference: pwrite/pread, execbuffer
-	 * (objects are not allowed multiple times for the same batchbuffer),
-	 * and the framebuffer code. When switching/pageflipping, the
-	 * framebuffer code has at most two buffers pinned per crtc.
+	 * How many users have pinned this object in GTT space.
 	 *
-	 * In the worst case this is 1 + 1 + 1 + 2*2 = 7. That would fit into 3
-	 * bits with absolutely no headroom. So use 4 bits.
+	 * This is a tightly bound, fairly small number of users, so we
+	 * stuff inside the flags field so that we can both check for overflow
+	 * and detect a no-op i915_vma_pin() in a single check, while also
+	 * pinning the vma.
+	 *
+	 * The worst case display setup would have the same vma pinned for
+	 * use on each plane on each crtc, while also building the next atomic
+	 * state and holding a pin for the length of the cleanup queue. In the
+	 * future, the flip queue may be increased from 1.
+	 * Estimated worst case: 3 [qlen] * 4 [max crtcs] * 7 [max planes] = 84
+	 *
+	 * For GEM, the number of concurrent users for pwrite/pread is
+	 * unbounded. For execbuffer, it is currently one but will in future
+	 * be extended to allow multiple clients to pin vma concurrently.
+	 *
+	 * We also use suballocated pages, with each suballocation claiming
+	 * its own pin on the shared vma. At present, this is limited to
+	 * exclusive cachelines of a single page, so a maximum of 64 possible
+	 * users.
 	 */
-#define I915_VMA_PIN_MASK 0xf
-#define I915_VMA_PIN_OVERFLOW	BIT(5)
+#define I915_VMA_PIN_MASK 0xff
+#define I915_VMA_PIN_OVERFLOW	BIT(8)
 
 	/** Flags and address space this VMA is bound to */
-#define I915_VMA_GLOBAL_BIND	BIT(6)
-#define I915_VMA_LOCAL_BIND	BIT(7)
+#define I915_VMA_GLOBAL_BIND	BIT(9)
+#define I915_VMA_LOCAL_BIND	BIT(10)
 #define I915_VMA_BIND_MASK (I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND | I915_VMA_PIN_OVERFLOW)
 
-#define I915_VMA_GGTT		BIT(8)
-#define I915_VMA_CAN_FENCE	BIT(9)
-#define I915_VMA_CLOSED		BIT(10)
-#define I915_VMA_USERFAULT_BIT	11
+#define I915_VMA_GGTT		BIT(11)
+#define I915_VMA_CAN_FENCE	BIT(12)
+#define I915_VMA_CLOSED		BIT(13)
+#define I915_VMA_USERFAULT_BIT	14
 #define I915_VMA_USERFAULT	BIT(I915_VMA_USERFAULT_BIT)
-#define I915_VMA_GGTT_WRITE	BIT(12)
+#define I915_VMA_GGTT_WRITE	BIT(15)
 
 	unsigned int active_count;
 	struct rb_root active;
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 16/23] drm/i915: Allocate a status page for each timeline
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (14 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 15/23] drm/i915: Enlarge vma->pin_count Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-18 11:19   ` Tvrtko Ursulin
  2019-01-17 14:34 ` [PATCH 17/23] drm/i915: Share per-timeline HWSP using a slab suballocator Chris Wilson
                   ` (11 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Allocate a page for use as a status page by a group of timelines, as we
only need a dword of storage for each (rounded up to the cacheline for
safety) we can pack multiple timelines into the same page. Each timeline
will then be able to track its own HW seqno.

v2: Reuse the common per-engine HWSP for the solitary ringbuffer
timeline, so that we do not have to emit (using per-gen specialised
vfuncs) the breadcrumb into the distinct timeline HWSP and instead can
keep on using the common MI_STORE_DWORD_INDEX. However, to maintain the
sleight-of-hand for the global/per-context seqno switchover, we will
store both temporarily (and so use a custom offset for the shared timeline
HWSP until the switch over).

v3: Keep things simple and allocate a page for each timeline, page
sharing comes next.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_timeline.c          | 106 ++++-
 drivers/gpu/drm/i915/i915_timeline.h          |  21 +-
 drivers/gpu/drm/i915/intel_engine_cs.c        |  64 +--
 drivers/gpu/drm/i915/intel_lrc.c              |  22 +-
 drivers/gpu/drm/i915/intel_ringbuffer.c       |  10 +-
 drivers/gpu/drm/i915/intel_ringbuffer.h       |   6 +-
 .../drm/i915/selftests/i915_live_selftests.h  |   1 +
 .../drm/i915/selftests/i915_mock_selftests.h  |   2 +-
 .../gpu/drm/i915/selftests/i915_timeline.c    | 373 +++++++++++++++++-
 drivers/gpu/drm/i915/selftests/mock_engine.c  |  17 +-
 10 files changed, 571 insertions(+), 51 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
index 84550f17d3df..380f4d25fb89 100644
--- a/drivers/gpu/drm/i915/i915_timeline.c
+++ b/drivers/gpu/drm/i915/i915_timeline.c
@@ -9,11 +9,38 @@
 #include "i915_timeline.h"
 #include "i915_syncmap.h"
 
-void i915_timeline_init(struct drm_i915_private *i915,
-			struct i915_timeline *timeline,
-			const char *name)
+static int hwsp_alloc(struct i915_timeline *timeline)
+{
+	struct drm_i915_private *i915 = timeline->i915;
+	struct drm_i915_gem_object *bo;
+	struct i915_vma *vma;
+
+	bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
+	if (IS_ERR(bo))
+		return PTR_ERR(bo);
+
+	i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
+
+	vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
+	if (IS_ERR(vma)) {
+		i915_gem_object_put(bo);
+		return PTR_ERR(vma);
+	}
+
+	timeline->hwsp_ggtt = vma;
+	timeline->hwsp_offset = 0;
+
+	return 0;
+}
+
+int i915_timeline_init(struct drm_i915_private *i915,
+		       struct i915_timeline *timeline,
+		       const char *name,
+		       struct i915_vma *global_hwsp)
 {
 	struct i915_gt_timelines *gt = &i915->gt.timelines;
+	void *vaddr;
+	int err;
 
 	/*
 	 * Ideally we want a set of engines on a single leaf as we expect
@@ -25,10 +52,27 @@ void i915_timeline_init(struct drm_i915_private *i915,
 
 	timeline->i915 = i915;
 	timeline->name = name;
+	timeline->pin_count = 0;
+
+	if (global_hwsp) {
+		timeline->hwsp_ggtt = i915_vma_get(global_hwsp);
+		timeline->hwsp_offset = I915_GEM_HWS_SEQNO_ADDR;
+	} else {
+		err = hwsp_alloc(timeline);
+		if (err)
+			return err;
+	}
 
-	mutex_lock(&gt->mutex);
-	list_add(&timeline->link, &gt->list);
-	mutex_unlock(&gt->mutex);
+	vaddr = i915_gem_object_pin_map(timeline->hwsp_ggtt->obj, I915_MAP_WB);
+	if (IS_ERR(vaddr)) {
+		i915_vma_put(timeline->hwsp_ggtt);
+		return PTR_ERR(vaddr);
+	}
+
+	timeline->hwsp_seqno =
+		memset(vaddr + timeline->hwsp_offset,
+		       0,
+		       sizeof(*timeline->hwsp_seqno));
 
 	/* Called during early_init before we know how many engines there are */
 
@@ -40,6 +84,12 @@ void i915_timeline_init(struct drm_i915_private *i915,
 	INIT_LIST_HEAD(&timeline->requests);
 
 	i915_syncmap_init(&timeline->sync);
+
+	mutex_lock(&gt->mutex);
+	list_add(&timeline->link, &gt->list);
+	mutex_unlock(&gt->mutex);
+
+	return 0;
 }
 
 void i915_timelines_init(struct drm_i915_private *i915)
@@ -85,6 +135,7 @@ void i915_timeline_fini(struct i915_timeline *timeline)
 {
 	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
 
+	GEM_BUG_ON(timeline->pin_count);
 	GEM_BUG_ON(!list_empty(&timeline->requests));
 
 	i915_syncmap_free(&timeline->sync);
@@ -92,23 +143,62 @@ void i915_timeline_fini(struct i915_timeline *timeline)
 	mutex_lock(&gt->mutex);
 	list_del(&timeline->link);
 	mutex_unlock(&gt->mutex);
+
+	i915_gem_object_unpin_map(timeline->hwsp_ggtt->obj);
+	i915_vma_put(timeline->hwsp_ggtt);
 }
 
 struct i915_timeline *
-i915_timeline_create(struct drm_i915_private *i915, const char *name)
+i915_timeline_create(struct drm_i915_private *i915,
+		     const char *name,
+		     struct i915_vma *global_hwsp)
 {
 	struct i915_timeline *timeline;
+	int err;
 
 	timeline = kzalloc(sizeof(*timeline), GFP_KERNEL);
 	if (!timeline)
 		return ERR_PTR(-ENOMEM);
 
-	i915_timeline_init(i915, timeline, name);
+	err = i915_timeline_init(i915, timeline, name, global_hwsp);
+	if (err) {
+		kfree(timeline);
+		return ERR_PTR(err);
+	}
+
 	kref_init(&timeline->kref);
 
 	return timeline;
 }
 
+int i915_timeline_pin(struct i915_timeline *tl)
+{
+	int err;
+
+	if (tl->pin_count++)
+		return 0;
+	GEM_BUG_ON(!tl->pin_count);
+
+	err = i915_vma_pin(tl->hwsp_ggtt, 0, 0, PIN_GLOBAL | PIN_HIGH);
+	if (err)
+		goto unpin;
+
+	return 0;
+
+unpin:
+	tl->pin_count = 0;
+	return err;
+}
+
+void i915_timeline_unpin(struct i915_timeline *tl)
+{
+	GEM_BUG_ON(!tl->pin_count);
+	if (--tl->pin_count)
+		return;
+
+	__i915_vma_unpin(tl->hwsp_ggtt);
+}
+
 void __i915_timeline_free(struct kref *kref)
 {
 	struct i915_timeline *timeline =
diff --git a/drivers/gpu/drm/i915/i915_timeline.h b/drivers/gpu/drm/i915/i915_timeline.h
index 87ad2dd31c20..0c3739d53d79 100644
--- a/drivers/gpu/drm/i915/i915_timeline.h
+++ b/drivers/gpu/drm/i915/i915_timeline.h
@@ -32,6 +32,8 @@
 #include "i915_syncmap.h"
 #include "i915_utils.h"
 
+struct i915_vma;
+
 struct i915_timeline {
 	u64 fence_context;
 	u32 seqno;
@@ -40,6 +42,11 @@ struct i915_timeline {
 #define TIMELINE_CLIENT 0 /* default subclass */
 #define TIMELINE_ENGINE 1
 
+	unsigned int pin_count;
+	const u32 *hwsp_seqno;
+	struct i915_vma *hwsp_ggtt;
+	u32 hwsp_offset;
+
 	/**
 	 * List of breadcrumbs associated with GPU requests currently
 	 * outstanding.
@@ -71,9 +78,10 @@ struct i915_timeline {
 	struct kref kref;
 };
 
-void i915_timeline_init(struct drm_i915_private *i915,
-			struct i915_timeline *tl,
-			const char *name);
+int i915_timeline_init(struct drm_i915_private *i915,
+		       struct i915_timeline *tl,
+		       const char *name,
+		       struct i915_vma *hwsp);
 void i915_timeline_fini(struct i915_timeline *tl);
 
 static inline void
@@ -96,7 +104,9 @@ i915_timeline_set_subclass(struct i915_timeline *timeline,
 }
 
 struct i915_timeline *
-i915_timeline_create(struct drm_i915_private *i915, const char *name);
+i915_timeline_create(struct drm_i915_private *i915,
+		     const char *name,
+		     struct i915_vma *global_hwsp);
 
 static inline struct i915_timeline *
 i915_timeline_get(struct i915_timeline *timeline)
@@ -135,6 +145,9 @@ static inline bool i915_timeline_sync_is_later(struct i915_timeline *tl,
 	return __i915_timeline_sync_is_later(tl, fence->context, fence->seqno);
 }
 
+int i915_timeline_pin(struct i915_timeline *tl);
+void i915_timeline_unpin(struct i915_timeline *tl);
+
 void i915_timelines_init(struct drm_i915_private *i915);
 void i915_timelines_park(struct drm_i915_private *i915);
 void i915_timelines_fini(struct drm_i915_private *i915);
diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index 4b4b7358c482..c850d131d8c3 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -484,26 +484,6 @@ static void intel_engine_init_execlist(struct intel_engine_cs *engine)
 	execlists->queue = RB_ROOT_CACHED;
 }
 
-/**
- * intel_engines_setup_common - setup engine state not requiring hw access
- * @engine: Engine to setup.
- *
- * Initializes @engine@ structure members shared between legacy and execlists
- * submission modes which do not require hardware access.
- *
- * Typically done early in the submission mode specific engine setup stage.
- */
-void intel_engine_setup_common(struct intel_engine_cs *engine)
-{
-	i915_timeline_init(engine->i915, &engine->timeline, engine->name);
-	i915_timeline_set_subclass(&engine->timeline, TIMELINE_ENGINE);
-
-	intel_engine_init_execlist(engine);
-	intel_engine_init_hangcheck(engine);
-	intel_engine_init_batch_pool(engine);
-	intel_engine_init_cmd_parser(engine);
-}
-
 static void cleanup_status_page(struct intel_engine_cs *engine)
 {
 	struct i915_vma *vma;
@@ -601,6 +581,44 @@ static int init_status_page(struct intel_engine_cs *engine)
 	return ret;
 }
 
+/**
+ * intel_engines_setup_common - setup engine state not requiring hw access
+ * @engine: Engine to setup.
+ *
+ * Initializes @engine@ structure members shared between legacy and execlists
+ * submission modes which do not require hardware access.
+ *
+ * Typically done early in the submission mode specific engine setup stage.
+ */
+int intel_engine_setup_common(struct intel_engine_cs *engine)
+{
+	int err;
+
+	err = init_status_page(engine);
+	if (err)
+		return err;
+
+	err = i915_timeline_init(engine->i915,
+				 &engine->timeline,
+				 engine->name,
+				 engine->status_page.vma);
+	if (err)
+		goto err_hwsp;
+
+	i915_timeline_set_subclass(&engine->timeline, TIMELINE_ENGINE);
+
+	intel_engine_init_execlist(engine);
+	intel_engine_init_hangcheck(engine);
+	intel_engine_init_batch_pool(engine);
+	intel_engine_init_cmd_parser(engine);
+
+	return 0;
+
+err_hwsp:
+	cleanup_status_page(engine);
+	return err;
+}
+
 static void __intel_context_unpin(struct i915_gem_context *ctx,
 				  struct intel_engine_cs *engine)
 {
@@ -653,14 +671,8 @@ int intel_engine_init_common(struct intel_engine_cs *engine)
 	if (ret)
 		goto err_unpin_preempt;
 
-	ret = init_status_page(engine);
-	if (ret)
-		goto err_breadcrumbs;
-
 	return 0;
 
-err_breadcrumbs:
-	intel_engine_fini_breadcrumbs(engine);
 err_unpin_preempt:
 	if (i915->preempt_context)
 		__intel_context_unpin(i915->preempt_context, engine);
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 4e942c403333..a624e644fbd7 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -2187,10 +2187,14 @@ logical_ring_default_irqs(struct intel_engine_cs *engine)
 	engine->irq_keep_mask = GT_CONTEXT_SWITCH_INTERRUPT << shift;
 }
 
-static void
+static int
 logical_ring_setup(struct intel_engine_cs *engine)
 {
-	intel_engine_setup_common(engine);
+	int err;
+
+	err = intel_engine_setup_common(engine);
+	if (err)
+		return err;
 
 	/* Intentionally left blank. */
 	engine->buffer = NULL;
@@ -2200,6 +2204,8 @@ logical_ring_setup(struct intel_engine_cs *engine)
 
 	logical_ring_default_vfuncs(engine);
 	logical_ring_default_irqs(engine);
+
+	return 0;
 }
 
 static int logical_ring_init(struct intel_engine_cs *engine)
@@ -2248,7 +2254,9 @@ int logical_render_ring_init(struct intel_engine_cs *engine)
 {
 	int ret;
 
-	logical_ring_setup(engine);
+	ret = logical_ring_setup(engine);
+	if (ret)
+		return ret;
 
 	/* Override some for render ring. */
 	engine->init_context = gen8_init_rcs_context;
@@ -2278,7 +2286,11 @@ int logical_render_ring_init(struct intel_engine_cs *engine)
 
 int logical_xcs_ring_init(struct intel_engine_cs *engine)
 {
-	logical_ring_setup(engine);
+	int err;
+
+	err = logical_ring_setup(engine);
+	if (err)
+		return err;
 
 	return logical_ring_init(engine);
 }
@@ -2612,7 +2624,7 @@ static int execlists_context_deferred_alloc(struct i915_gem_context *ctx,
 		goto error_deref_obj;
 	}
 
-	timeline = i915_timeline_create(ctx->i915, ctx->name);
+	timeline = i915_timeline_create(ctx->i915, ctx->name, NULL);
 	if (IS_ERR(timeline)) {
 		ret = PTR_ERR(timeline);
 		goto error_deref_obj;
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index d72012b42f20..5887304bc3ae 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1539,9 +1539,13 @@ static int intel_init_ring_buffer(struct intel_engine_cs *engine)
 	struct intel_ring *ring;
 	int err;
 
-	intel_engine_setup_common(engine);
+	err = intel_engine_setup_common(engine);
+	if (err)
+		return err;
 
-	timeline = i915_timeline_create(engine->i915, engine->name);
+	timeline = i915_timeline_create(engine->i915,
+					engine->name,
+					engine->status_page.vma);
 	if (IS_ERR(timeline)) {
 		err = PTR_ERR(timeline);
 		goto err;
@@ -1565,6 +1569,8 @@ static int intel_init_ring_buffer(struct intel_engine_cs *engine)
 	if (err)
 		goto err_unpin;
 
+	GEM_BUG_ON(ring->timeline->hwsp_ggtt != engine->status_page.vma);
+
 	return 0;
 
 err_unpin:
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 9972c9016445..5c20b41b6a9b 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -716,7 +716,9 @@ intel_write_status_page(struct intel_engine_cs *engine, int reg, u32 value)
 #define I915_GEM_HWS_INDEX_ADDR (I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
 #define I915_GEM_HWS_PREEMPT_INDEX	0x32
 #define I915_GEM_HWS_PREEMPT_ADDR (I915_GEM_HWS_PREEMPT_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
-#define I915_GEM_HWS_SCRATCH_INDEX	0x40
+#define I915_GEM_HWS_SEQNO		0x40
+#define I915_GEM_HWS_SEQNO_ADDR (I915_GEM_HWS_SEQNO << MI_STORE_DWORD_INDEX_SHIFT)
+#define I915_GEM_HWS_SCRATCH_INDEX	0x80
 #define I915_GEM_HWS_SCRATCH_ADDR (I915_GEM_HWS_SCRATCH_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
 
 #define I915_HWS_CSB_BUF0_INDEX		0x10
@@ -822,7 +824,7 @@ intel_ring_set_tail(struct intel_ring *ring, unsigned int tail)
 
 void intel_engine_write_global_seqno(struct intel_engine_cs *engine, u32 seqno);
 
-void intel_engine_setup_common(struct intel_engine_cs *engine);
+int intel_engine_setup_common(struct intel_engine_cs *engine);
 int intel_engine_init_common(struct intel_engine_cs *engine);
 void intel_engine_cleanup_common(struct intel_engine_cs *engine);
 
diff --git a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
index a15713cae3b3..76b4f87fc853 100644
--- a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
+++ b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
@@ -13,6 +13,7 @@ selftest(sanitycheck, i915_live_sanitycheck) /* keep first (igt selfcheck) */
 selftest(uncore, intel_uncore_live_selftests)
 selftest(workarounds, intel_workarounds_live_selftests)
 selftest(requests, i915_request_live_selftests)
+selftest(timelines, i915_timeline_live_selftests)
 selftest(objects, i915_gem_object_live_selftests)
 selftest(dmabuf, i915_gem_dmabuf_live_selftests)
 selftest(coherency, i915_gem_coherency_live_selftests)
diff --git a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
index 1b70208eeea7..4a83a1c6c406 100644
--- a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
+++ b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
@@ -16,7 +16,7 @@ selftest(syncmap, i915_syncmap_mock_selftests)
 selftest(uncore, intel_uncore_mock_selftests)
 selftest(engine, intel_engine_cs_mock_selftests)
 selftest(breadcrumbs, intel_breadcrumbs_mock_selftests)
-selftest(timelines, i915_gem_timeline_mock_selftests)
+selftest(timelines, i915_timeline_mock_selftests)
 selftest(requests, i915_request_mock_selftests)
 selftest(objects, i915_gem_object_mock_selftests)
 selftest(dmabuf, i915_gem_dmabuf_mock_selftests)
diff --git a/drivers/gpu/drm/i915/selftests/i915_timeline.c b/drivers/gpu/drm/i915/selftests/i915_timeline.c
index 19f1c6a5c8fb..d13779808200 100644
--- a/drivers/gpu/drm/i915/selftests/i915_timeline.c
+++ b/drivers/gpu/drm/i915/selftests/i915_timeline.c
@@ -256,7 +256,7 @@ static int bench_sync(void *arg)
 	return 0;
 }
 
-int i915_gem_timeline_mock_selftests(void)
+int i915_timeline_mock_selftests(void)
 {
 	static const struct i915_subtest tests[] = {
 		SUBTEST(igt_sync),
@@ -265,3 +265,374 @@ int i915_gem_timeline_mock_selftests(void)
 
 	return i915_subtests(tests, NULL);
 }
+
+static int live_hwsp_engine(void *arg)
+{
+#define NUM_TIMELINES 4096
+	struct drm_i915_private *i915 = arg;
+	struct i915_timeline **timelines;
+	struct intel_engine_cs *engine;
+	enum intel_engine_id id;
+	intel_wakeref_t wakeref;
+	unsigned long count, n;
+	int err = 0;
+
+	/*
+	 * Create a bunch of timelines and check we can write
+	 * independently to each of their breadcrumb slots.
+	 */
+
+	timelines = kvmalloc_array(NUM_TIMELINES * I915_NUM_ENGINES,
+				   sizeof(*timelines),
+				   GFP_KERNEL);
+	if (!timelines)
+		return -ENOMEM;
+
+	mutex_lock(&i915->drm.struct_mutex);
+	wakeref = intel_runtime_pm_get(i915);
+
+	count = 0;
+	for_each_engine(engine, i915, id) {
+		if (!intel_engine_can_store_dword(engine))
+			continue;
+
+		for (n = 0; n < NUM_TIMELINES; n++) {
+			struct i915_timeline *tl;
+			struct i915_request *rq;
+			u32 addr;
+			u32 *cs;
+
+			tl = i915_timeline_create(i915, "live", NULL);
+			if (IS_ERR(tl)) {
+				err = PTR_ERR(tl);
+				goto out;
+			}
+
+			if (*tl->hwsp_seqno) {
+				pr_err("Timeline %lu created with non-zero breadcrumb, found %x\n",
+				       count, *tl->hwsp_seqno);
+				err = -EINVAL;
+				i915_timeline_put(tl);
+				goto out;
+			}
+
+			err = i915_timeline_pin(tl);
+			if (err) {
+				i915_timeline_put(tl);
+				goto out;
+			}
+
+			rq = i915_request_alloc(engine, i915->kernel_context);
+			if (IS_ERR(rq)) {
+				i915_timeline_unpin(tl);
+				i915_timeline_put(tl);
+				err = PTR_ERR(rq);
+				goto out;
+			}
+
+			cs = intel_ring_begin(rq, 4);
+			if (IS_ERR(cs)) {
+				i915_request_add(rq);
+				i915_timeline_unpin(tl);
+				i915_timeline_put(tl);
+				err = PTR_ERR(cs);
+				goto out;
+			}
+
+			addr = i915_ggtt_offset(tl->hwsp_ggtt) + tl->hwsp_offset;
+
+			if (INTEL_GEN(i915) >= 8) {
+				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+				*cs++ = addr;
+				*cs++ = 0;
+				*cs++ = count;
+			} else if (INTEL_GEN(i915) >= 4) {
+				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+				*cs++ = 0;
+				*cs++ = addr;
+				*cs++ = count;
+			} else {
+				*cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
+				*cs++ = addr;
+				*cs++ = count;
+				*cs++ = MI_NOOP;
+			}
+			intel_ring_advance(rq, cs);
+
+			i915_request_add(rq);
+			i915_timeline_unpin(tl);
+
+			timelines[count++] = tl;
+		}
+	}
+
+	err = i915_gem_wait_for_idle(i915, I915_WAIT_LOCKED, MAX_SCHEDULE_TIMEOUT);
+
+out:
+	for (n = 0; n < count; n++) {
+		struct i915_timeline *tl = timelines[n];
+
+		if (!err && *tl->hwsp_seqno != n) {
+			pr_err("Invalid seqno stored in timeline %lu, found 0x%x\n",
+			       n, *tl->hwsp_seqno);
+			err = -EINVAL;
+		}
+		i915_timeline_put(tl);
+	}
+
+	intel_runtime_pm_put(i915, wakeref);
+	mutex_unlock(&i915->drm.struct_mutex);
+
+	kvfree(timelines);
+
+	return err;
+#undef NUM_TIMELINES
+}
+
+static int live_hwsp_alternate(void *arg)
+{
+#define NUM_TIMELINES 4096
+	struct drm_i915_private *i915 = arg;
+	struct i915_timeline **timelines;
+	struct intel_engine_cs *engine;
+	enum intel_engine_id id;
+	intel_wakeref_t wakeref;
+	unsigned long count, n;
+	int err = 0;
+
+	/*
+	 * Create a bunch of timelines and check we can write
+	 * independently to each of their breadcrumb slots with adjacent
+	 * engines.
+	 */
+
+	timelines = kvmalloc_array(NUM_TIMELINES * I915_NUM_ENGINES,
+				   sizeof(*timelines),
+				   GFP_KERNEL);
+	if (!timelines)
+		return -ENOMEM;
+
+	mutex_lock(&i915->drm.struct_mutex);
+	wakeref = intel_runtime_pm_get(i915);
+
+	count = 0;
+	for (n = 0; n < NUM_TIMELINES; n++) {
+		for_each_engine(engine, i915, id) {
+			struct i915_timeline *tl;
+			struct i915_request *rq;
+			u32 addr;
+			u32 *cs;
+
+			if (!intel_engine_can_store_dword(engine))
+				continue;
+
+			tl = i915_timeline_create(i915, "live", NULL);
+			if (IS_ERR(tl)) {
+				err = PTR_ERR(tl);
+				goto out;
+			}
+
+			if (*tl->hwsp_seqno) {
+				pr_err("Timeline %lu created with non-zero breadcrumb, found %x\n",
+				       count, *tl->hwsp_seqno);
+				err = -EINVAL;
+				i915_timeline_put(tl);
+				goto out;
+			}
+
+			err = i915_timeline_pin(tl);
+			if (err) {
+				i915_timeline_put(tl);
+				goto out;
+			}
+
+			rq = i915_request_alloc(engine, i915->kernel_context);
+			if (IS_ERR(rq)) {
+				i915_timeline_unpin(tl);
+				i915_timeline_put(tl);
+				err = PTR_ERR(rq);
+				goto out;
+			}
+
+			cs = intel_ring_begin(rq, 4);
+			if (IS_ERR(cs)) {
+				i915_request_add(rq);
+				i915_timeline_unpin(tl);
+				i915_timeline_put(tl);
+				err = PTR_ERR(cs);
+				goto out;
+			}
+
+			addr = i915_ggtt_offset(tl->hwsp_ggtt) + tl->hwsp_offset;
+
+			if (INTEL_GEN(i915) >= 8) {
+				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+				*cs++ = addr;
+				*cs++ = 0;
+				*cs++ = count;
+			} else if (INTEL_GEN(i915) >= 4) {
+				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+				*cs++ = 0;
+				*cs++ = addr;
+				*cs++ = count;
+			} else {
+				*cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
+				*cs++ = addr;
+				*cs++ = count;
+				*cs++ = MI_NOOP;
+			}
+			intel_ring_advance(rq, cs);
+
+			i915_request_add(rq);
+			i915_timeline_unpin(tl);
+
+			timelines[count++] = tl;
+		}
+	}
+
+	err = i915_gem_wait_for_idle(i915, I915_WAIT_LOCKED, MAX_SCHEDULE_TIMEOUT);
+
+out:
+	for (n = 0; n < count; n++) {
+		struct i915_timeline *tl = timelines[n];
+
+		if (!err && *tl->hwsp_seqno != n) {
+			pr_err("Invalid seqno stored in timeline %lu, found 0x%x\n",
+			       n, *tl->hwsp_seqno);
+			err = -EINVAL;
+		}
+		i915_timeline_put(tl);
+	}
+
+	intel_runtime_pm_put(i915, wakeref);
+	mutex_unlock(&i915->drm.struct_mutex);
+
+	kvfree(timelines);
+
+	return err;
+#undef NUM_TIMELINES
+}
+
+static int live_hwsp_recycle(void *arg)
+{
+	struct drm_i915_private *i915 = arg;
+	struct intel_engine_cs *engine;
+	enum intel_engine_id id;
+	intel_wakeref_t wakeref;
+	unsigned long count;
+	int err = 0;
+
+	/*
+	 * Check seqno writes into one timeline at a time. We expect to
+	 * recycle the breadcrumb slot between iterations and neither
+	 * want to confuse ourselves or the GPU.
+	 */
+
+	mutex_lock(&i915->drm.struct_mutex);
+	wakeref = intel_runtime_pm_get(i915);
+
+	count = 0;
+	for_each_engine(engine, i915, id) {
+		IGT_TIMEOUT(end_time);
+
+		if (!intel_engine_can_store_dword(engine))
+			continue;
+
+		do {
+			struct i915_timeline *tl;
+			struct i915_request *rq;
+			u32 addr;
+			u32 *cs;
+
+			tl = i915_timeline_create(i915, "live", NULL);
+			if (IS_ERR(tl)) {
+				err = PTR_ERR(tl);
+				goto out;
+			}
+
+			if (*tl->hwsp_seqno) {
+				pr_err("Timeline %lu created with non-zero breadcrumb, found %x\n",
+				       count, *tl->hwsp_seqno);
+				err = -EINVAL;
+				i915_timeline_put(tl);
+				goto out;
+			}
+
+			err = i915_timeline_pin(tl);
+			if (err) {
+				i915_timeline_put(tl);
+				goto out;
+			}
+
+			rq = i915_request_alloc(engine, i915->kernel_context);
+			if (IS_ERR(rq)) {
+				i915_timeline_unpin(tl);
+				i915_timeline_put(tl);
+				err = PTR_ERR(rq);
+				goto out;
+			}
+
+			cs = intel_ring_begin(rq, 4);
+			if (IS_ERR(cs)) {
+				i915_request_add(rq);
+				i915_timeline_unpin(tl);
+				i915_timeline_put(tl);
+				err = PTR_ERR(cs);
+				goto out;
+			}
+
+			addr = i915_ggtt_offset(tl->hwsp_ggtt) + tl->hwsp_offset;
+
+			if (INTEL_GEN(i915) >= 8) {
+				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+				*cs++ = addr;
+				*cs++ = 0;
+				*cs++ = count;
+			} else if (INTEL_GEN(i915) >= 4) {
+				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+				*cs++ = 0;
+				*cs++ = addr;
+				*cs++ = count;
+			} else {
+				*cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
+				*cs++ = addr;
+				*cs++ = count;
+				*cs++ = MI_NOOP;
+			}
+			intel_ring_advance(rq, cs);
+
+			i915_request_add(rq);
+			i915_timeline_unpin(tl);
+
+			i915_request_wait(rq, I915_WAIT_LOCKED, MAX_SCHEDULE_TIMEOUT);
+			if (*tl->hwsp_seqno != count) {
+				pr_err("Invalid seqno stored in timeline %lu, found 0x%x\n",
+				       count, *tl->hwsp_seqno);
+				err = -EINVAL;
+			}
+
+			i915_timeline_put(tl);
+			count++;
+
+			if (err)
+				goto out;
+		} while (!__igt_timeout(end_time, NULL));
+	}
+
+out:
+	intel_runtime_pm_put(i915, wakeref);
+	mutex_unlock(&i915->drm.struct_mutex);
+
+	return err;
+}
+
+int i915_timeline_live_selftests(struct drm_i915_private *i915)
+{
+	static const struct i915_subtest tests[] = {
+		SUBTEST(live_hwsp_recycle),
+		SUBTEST(live_hwsp_engine),
+		SUBTEST(live_hwsp_alternate),
+	};
+
+	return i915_subtests(tests, i915);
+}
diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
index 968a7e139a67..acd27c7e807b 100644
--- a/drivers/gpu/drm/i915/selftests/mock_engine.c
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
@@ -34,12 +34,20 @@ static struct intel_ring *mock_ring(struct intel_engine_cs *engine)
 {
 	const unsigned long sz = PAGE_SIZE / 2;
 	struct mock_ring *ring;
+	int err;
 
 	ring = kzalloc(sizeof(*ring) + sz, GFP_KERNEL);
 	if (!ring)
 		return NULL;
 
-	i915_timeline_init(engine->i915, &ring->timeline, engine->name);
+	err = i915_timeline_init(engine->i915,
+				 &ring->timeline,
+				 engine->name,
+				 NULL);
+	if (err) {
+		kfree(ring);
+		return NULL;
+	}
 
 	ring->base.size = sz;
 	ring->base.effective_size = sz;
@@ -209,7 +217,11 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
 	engine->base.emit_breadcrumb = mock_emit_breadcrumb;
 	engine->base.submit_request = mock_submit_request;
 
-	i915_timeline_init(i915, &engine->base.timeline, engine->base.name);
+	if (i915_timeline_init(i915,
+			       &engine->base.timeline,
+			       engine->base.name,
+			       NULL))
+		goto err_free;
 	i915_timeline_set_subclass(&engine->base.timeline, TIMELINE_ENGINE);
 
 	intel_engine_init_breadcrumbs(&engine->base);
@@ -227,6 +239,7 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
 err_breadcrumbs:
 	intel_engine_fini_breadcrumbs(&engine->base);
 	i915_timeline_fini(&engine->base.timeline);
+err_free:
 	kfree(engine);
 	return NULL;
 }
-- 
2.20.1

_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 17/23] drm/i915: Share per-timeline HWSP using a slab suballocator
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (15 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 16/23] drm/i915: Allocate a status page for each timeline Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-18 12:08   ` Tvrtko Ursulin
  2019-01-17 14:34 ` [PATCH 18/23] drm/i915: Keep all partially allocated HWSP on a freelist Chris Wilson
                   ` (10 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

If we restrict ourselves to only using a cacheline for each timeline's
HWSP (we could go smaller, but want to avoid needless polluting
cachelines on different engines between different contexts), then we can
suballocate a single 4k page into 64 different timeline HWSP. By
treating each fresh allocation as a slab of 64 entries, we can keep it
around for the next 64 allocation attempts until we need to refresh the
slab cache.

John Harrison noted the issue of fragmentation leading to the same worst
case performance of one page per timeline as before, which can be
mitigated by adopting a freelist.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Harrison <John.C.Harrison@Intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h      |  5 ++
 drivers/gpu/drm/i915/i915_timeline.c | 80 ++++++++++++++++++++++++----
 2 files changed, 74 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 3913900600b7..d59228dabb6e 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1978,6 +1978,11 @@ struct drm_i915_private {
 		struct i915_gt_timelines {
 			struct mutex mutex; /* protects list, tainted by GPU */
 			struct list_head list;
+
+			/* Pack multiple timelines' seqnos into the same page */
+			spinlock_t hwsp_lock;
+			struct i915_vma *hwsp;
+			u64 bitmap;
 		} timelines;
 
 		struct list_head active_rings;
diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
index 380f4d25fb89..e939a9e1a4ab 100644
--- a/drivers/gpu/drm/i915/i915_timeline.c
+++ b/drivers/gpu/drm/i915/i915_timeline.c
@@ -11,26 +11,73 @@
 
 static int hwsp_alloc(struct i915_timeline *timeline)
 {
+#define NBITS BITS_PER_TYPE(typeof(gt->bitmap))
 	struct drm_i915_private *i915 = timeline->i915;
-	struct drm_i915_gem_object *bo;
+	struct i915_gt_timelines *gt = &i915->gt.timelines;
 	struct i915_vma *vma;
+	int offset;
+
+	spin_lock(&gt->hwsp_lock);
+
+restart:
+	offset = find_first_bit((unsigned long *)&gt->bitmap, NBITS);
+	if (offset == NBITS && gt->hwsp) {
+		i915_vma_put(gt->hwsp);
+		gt->hwsp = NULL;
+	}
+
+	vma = gt->hwsp;
+	if (!vma) {
+		struct drm_i915_gem_object *bo;
+
+		spin_unlock(&gt->hwsp_lock);
 
-	bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
-	if (IS_ERR(bo))
-		return PTR_ERR(bo);
+		BUILD_BUG_ON(NBITS * CACHELINE_BYTES > PAGE_SIZE);
+		bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
+		if (IS_ERR(bo))
+			return PTR_ERR(bo);
 
-	i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
+		i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
 
-	vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
-	if (IS_ERR(vma)) {
-		i915_gem_object_put(bo);
-		return PTR_ERR(vma);
+		vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
+		if (IS_ERR(vma)) {
+			i915_gem_object_put(bo);
+			return PTR_ERR(vma);
+		}
+
+		spin_lock(&gt->hwsp_lock);
+		if (gt->hwsp) {
+			i915_gem_object_put(bo);
+			goto restart;
+		}
+
+		gt->hwsp = vma;
+		gt->bitmap = ~0ull;
+		offset = 0;
 	}
 
-	timeline->hwsp_ggtt = vma;
-	timeline->hwsp_offset = 0;
+	gt->bitmap &= ~BIT_ULL(offset);
+
+	spin_unlock(&gt->hwsp_lock);
+
+	timeline->hwsp_ggtt = i915_vma_get(vma);
+	timeline->hwsp_offset = offset * CACHELINE_BYTES;
 
 	return 0;
+#undef NBITS
+}
+
+static void hwsp_free(struct i915_timeline *timeline)
+{
+	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
+
+	if (timeline->hwsp_ggtt != gt->hwsp)
+		return;
+
+	spin_lock(&gt->hwsp_lock);
+	if (timeline->hwsp_ggtt == gt->hwsp)
+		gt->bitmap |= BIT_ULL(timeline->hwsp_offset / CACHELINE_BYTES);
+	spin_unlock(&gt->hwsp_lock);
 }
 
 int i915_timeline_init(struct drm_i915_private *i915,
@@ -65,6 +112,7 @@ int i915_timeline_init(struct drm_i915_private *i915,
 
 	vaddr = i915_gem_object_pin_map(timeline->hwsp_ggtt->obj, I915_MAP_WB);
 	if (IS_ERR(vaddr)) {
+		hwsp_free(timeline);
 		i915_vma_put(timeline->hwsp_ggtt);
 		return PTR_ERR(vaddr);
 	}
@@ -99,6 +147,8 @@ void i915_timelines_init(struct drm_i915_private *i915)
 	mutex_init(&gt->mutex);
 	INIT_LIST_HEAD(&gt->list);
 
+	spin_lock_init(&gt->hwsp_lock);
+
 	/* via i915_gem_wait_for_idle() */
 	i915_gem_shrinker_taints_mutex(i915, &gt->mutex);
 }
@@ -144,6 +194,9 @@ void i915_timeline_fini(struct i915_timeline *timeline)
 	list_del(&timeline->link);
 	mutex_unlock(&gt->mutex);
 
+	i915_syncmap_free(&timeline->sync);
+	hwsp_free(timeline);
+
 	i915_gem_object_unpin_map(timeline->hwsp_ggtt->obj);
 	i915_vma_put(timeline->hwsp_ggtt);
 }
@@ -211,9 +264,14 @@ void __i915_timeline_free(struct kref *kref)
 void i915_timelines_fini(struct drm_i915_private *i915)
 {
 	struct i915_gt_timelines *gt = &i915->gt.timelines;
+	struct i915_vma *vma;
 
 	GEM_BUG_ON(!list_empty(&gt->list));
 
+	vma = fetch_and_zero(&i915->gt.timelines.hwsp);
+	if (vma)
+		i915_vma_put(vma);
+
 	mutex_destroy(&gt->mutex);
 }
 
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 18/23] drm/i915: Keep all partially allocated HWSP on a freelist
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (16 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 17/23] drm/i915: Share per-timeline HWSP using a slab suballocator Chris Wilson
@ 2019-01-17 14:34 ` Chris Wilson
  2019-01-18 12:12   ` Mika Kuoppala
  2019-01-18 12:25   ` Tvrtko Ursulin
  2019-01-17 14:35 ` [PATCH 19/23] drm/i915: Track the context's seqno in its own timeline HWSP Chris Wilson
                   ` (9 subsequent siblings)
  27 siblings, 2 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:34 UTC (permalink / raw)
  To: intel-gfx

Keep track of partially allocated pages for use in allocating future
timeline HWSP. This is still without migration, so it is possible for
the system to end up with each timeline in its own page, but we ensure
that no new allocation would needless allocate a fresh page!

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Harrison <John.C.Harrison@Intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h      |  3 +-
 drivers/gpu/drm/i915/i915_timeline.c | 81 +++++++++++++++++-----------
 2 files changed, 50 insertions(+), 34 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index d59228dabb6e..0bebef428f1e 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1981,8 +1981,7 @@ struct drm_i915_private {
 
 			/* Pack multiple timelines' seqnos into the same page */
 			spinlock_t hwsp_lock;
-			struct i915_vma *hwsp;
-			u64 bitmap;
+			struct list_head hwsp;
 		} timelines;
 
 		struct list_head active_rings;
diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
index e939a9e1a4ab..64bb1ce24318 100644
--- a/drivers/gpu/drm/i915/i915_timeline.c
+++ b/drivers/gpu/drm/i915/i915_timeline.c
@@ -9,74 +9,94 @@
 #include "i915_timeline.h"
 #include "i915_syncmap.h"
 
+struct i915_timeline_hwsp {
+	struct list_head link;
+	struct i915_vma *vma;
+	u64 bitmap;
+};
+
 static int hwsp_alloc(struct i915_timeline *timeline)
 {
-#define NBITS BITS_PER_TYPE(typeof(gt->bitmap))
 	struct drm_i915_private *i915 = timeline->i915;
 	struct i915_gt_timelines *gt = &i915->gt.timelines;
-	struct i915_vma *vma;
+	struct i915_timeline_hwsp *hwsp;
 	int offset;
 
 	spin_lock(&gt->hwsp_lock);
 
-restart:
-	offset = find_first_bit((unsigned long *)&gt->bitmap, NBITS);
-	if (offset == NBITS && gt->hwsp) {
-		i915_vma_put(gt->hwsp);
-		gt->hwsp = NULL;
-	}
-
-	vma = gt->hwsp;
-	if (!vma) {
+	hwsp = list_first_entry_or_null(&gt->hwsp, typeof(*hwsp), link);
+	if (!hwsp) {
 		struct drm_i915_gem_object *bo;
+		struct i915_vma *vma;
 
 		spin_unlock(&gt->hwsp_lock);
 
-		BUILD_BUG_ON(NBITS * CACHELINE_BYTES > PAGE_SIZE);
+		hwsp = kmalloc(sizeof(*hwsp), GFP_KERNEL);
+		if (!hwsp)
+			return -ENOMEM;
+
+		BUILD_BUG_ON(BITS_PER_TYPE(hwsp->bitmap) * CACHELINE_BYTES > PAGE_SIZE);
 		bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
-		if (IS_ERR(bo))
+		if (IS_ERR(bo)) {
+			kfree(hwsp);
 			return PTR_ERR(bo);
+		}
 
 		i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
 
 		vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
 		if (IS_ERR(vma)) {
 			i915_gem_object_put(bo);
+			kfree(hwsp);
 			return PTR_ERR(vma);
 		}
 
-		spin_lock(&gt->hwsp_lock);
-		if (gt->hwsp) {
-			i915_gem_object_put(bo);
-			goto restart;
-		}
+		vma->private = hwsp;
+		hwsp->vma = vma;
+		hwsp->bitmap = ~0ull;
 
-		gt->hwsp = vma;
-		gt->bitmap = ~0ull;
-		offset = 0;
+		spin_lock(&gt->hwsp_lock);
+		list_add(&hwsp->link, &gt->hwsp);
 	}
 
-	gt->bitmap &= ~BIT_ULL(offset);
+	GEM_BUG_ON(!hwsp->bitmap);
+	offset = __ffs64(hwsp->bitmap);
+	hwsp->bitmap &= ~BIT_ULL(offset);
+	if (!hwsp->bitmap)
+		list_del(&hwsp->link);
 
 	spin_unlock(&gt->hwsp_lock);
 
-	timeline->hwsp_ggtt = i915_vma_get(vma);
+	timeline->hwsp_ggtt = i915_vma_get(hwsp->vma);
 	timeline->hwsp_offset = offset * CACHELINE_BYTES;
 
+	GEM_BUG_ON(timeline->hwsp_ggtt->private != hwsp);
+
 	return 0;
-#undef NBITS
 }
 
 static void hwsp_free(struct i915_timeline *timeline)
 {
 	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
+	struct i915_timeline_hwsp *hwsp;
 
-	if (timeline->hwsp_ggtt != gt->hwsp)
+	hwsp = timeline->hwsp_ggtt->private;
+	if (!hwsp)
 		return;
 
 	spin_lock(&gt->hwsp_lock);
-	if (timeline->hwsp_ggtt == gt->hwsp)
-		gt->bitmap |= BIT_ULL(timeline->hwsp_offset / CACHELINE_BYTES);
+
+	if (!hwsp->bitmap)
+		list_add_tail(&hwsp->link, &gt->hwsp);
+
+	hwsp->bitmap |= BIT_ULL(timeline->hwsp_offset / CACHELINE_BYTES);
+
+	if (hwsp->bitmap == ~0ull) {
+		i915_vma_put(hwsp->vma);
+		list_del(&hwsp->link);
+		kfree(hwsp);
+	}
+
 	spin_unlock(&gt->hwsp_lock);
 }
 
@@ -148,6 +168,7 @@ void i915_timelines_init(struct drm_i915_private *i915)
 	INIT_LIST_HEAD(&gt->list);
 
 	spin_lock_init(&gt->hwsp_lock);
+	INIT_LIST_HEAD(&gt->hwsp);
 
 	/* via i915_gem_wait_for_idle() */
 	i915_gem_shrinker_taints_mutex(i915, &gt->mutex);
@@ -264,13 +285,9 @@ void __i915_timeline_free(struct kref *kref)
 void i915_timelines_fini(struct drm_i915_private *i915)
 {
 	struct i915_gt_timelines *gt = &i915->gt.timelines;
-	struct i915_vma *vma;
 
 	GEM_BUG_ON(!list_empty(&gt->list));
-
-	vma = fetch_and_zero(&i915->gt.timelines.hwsp);
-	if (vma)
-		i915_vma_put(vma);
+	GEM_BUG_ON(!list_empty(&gt->hwsp));
 
 	mutex_destroy(&gt->mutex);
 }
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 19/23] drm/i915: Track the context's seqno in its own timeline HWSP
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (17 preceding siblings ...)
  2019-01-17 14:34 ` [PATCH 18/23] drm/i915: Keep all partially allocated HWSP on a freelist Chris Wilson
@ 2019-01-17 14:35 ` Chris Wilson
  2019-01-18 14:10   ` Tvrtko Ursulin
  2019-01-17 14:35 ` [PATCH 20/23] drm/i915: Identify active requests Chris Wilson
                   ` (8 subsequent siblings)
  27 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:35 UTC (permalink / raw)
  To: intel-gfx

Now that we have allocated ourselves a cacheline to store a breadcrumb,
we can emit a write from the GPU into the timeline's HWSP of the
per-context seqno as we complete each request. This drops the mirroring
of the per-engine HWSP and allows each context to operate independently.
We do not need to unwind the per-context timeline, and so requests are
always consistent with the timeline breadcrumb, greatly simplifying the
completion checks as we no longer need to be concerned about the
global_seqno changing mid check.

At this point, we are emitting both per-context and global seqno and
still using the single per-engine execution timeline for resolving
interrupts.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.c              |  2 +-
 drivers/gpu/drm/i915/i915_request.c          |  2 +-
 drivers/gpu/drm/i915/i915_request.h          | 27 ++----
 drivers/gpu/drm/i915/i915_reset.c            |  1 +
 drivers/gpu/drm/i915/i915_vma.h              |  7 ++
 drivers/gpu/drm/i915/intel_lrc.c             | 32 ++++---
 drivers/gpu/drm/i915/intel_ringbuffer.c      | 91 ++++++++++++++------
 drivers/gpu/drm/i915/selftests/mock_engine.c |  8 +-
 8 files changed, 109 insertions(+), 61 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 3c6091021290..a5bd51987c0d 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2890,7 +2890,7 @@ i915_gem_find_active_request(struct intel_engine_cs *engine)
 	 */
 	spin_lock_irqsave(&engine->timeline.lock, flags);
 	list_for_each_entry(request, &engine->timeline.requests, link) {
-		if (__i915_request_completed(request, request->global_seqno))
+		if (i915_request_completed(request))
 			continue;
 
 		active = request;
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 7d068c406a49..0d7b71aff28f 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -614,7 +614,7 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx)
 	rq->ring = ce->ring;
 	rq->timeline = ce->ring->timeline;
 	GEM_BUG_ON(rq->timeline == &engine->timeline);
-	rq->hwsp_seqno = &engine->status_page.addr[I915_GEM_HWS_INDEX];
+	rq->hwsp_seqno = rq->timeline->hwsp_seqno;
 
 	spin_lock_init(&rq->lock);
 	dma_fence_init(&rq->fence,
diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h
index 4dd22dadf5ce..a16a3b7f7d92 100644
--- a/drivers/gpu/drm/i915/i915_request.h
+++ b/drivers/gpu/drm/i915/i915_request.h
@@ -324,32 +324,21 @@ static inline u32 hwsp_seqno(const struct i915_request *rq)
  */
 static inline bool i915_request_started(const struct i915_request *rq)
 {
-	u32 seqno;
-
-	seqno = i915_request_global_seqno(rq);
-	if (!seqno) /* not yet submitted to HW */
-		return false;
-
-	return i915_seqno_passed(hwsp_seqno(rq), seqno - 1);
+	return i915_seqno_passed(hwsp_seqno(rq), rq->fence.seqno - 1);
 }
 
-static inline bool
-__i915_request_completed(const struct i915_request *rq, u32 seqno)
+static inline bool i915_request_completed(const struct i915_request *rq)
 {
-	GEM_BUG_ON(!seqno);
-	return i915_seqno_passed(hwsp_seqno(rq), seqno) &&
-		seqno == i915_request_global_seqno(rq);
+	return i915_seqno_passed(hwsp_seqno(rq), rq->fence.seqno);
 }
 
-static inline bool i915_request_completed(const struct i915_request *rq)
+static inline void i915_request_fake_complete(const struct i915_request *rq)
 {
-	u32 seqno;
-
-	seqno = i915_request_global_seqno(rq);
-	if (!seqno)
-		return false;
+	/* Don't allow ourselves to accidentally go backwards. */
+	if (i915_request_completed(rq))
+		return;
 
-	return __i915_request_completed(rq, seqno);
+	WRITE_ONCE(*(u32 *)rq->hwsp_seqno, rq->fence.seqno);
 }
 
 void i915_retire_requests(struct drm_i915_private *i915);
diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index 12e5a2bc825c..eff76558b958 100644
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -756,6 +756,7 @@ static void nop_submit_request(struct i915_request *request)
 
 	spin_lock_irqsave(&request->engine->timeline.lock, flags);
 	__i915_request_submit(request);
+	i915_request_fake_complete(request);
 	intel_engine_write_global_seqno(request->engine, request->global_seqno);
 	spin_unlock_irqrestore(&request->engine->timeline.lock, flags);
 }
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 5793abe509a2..18be786a970d 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -221,6 +221,13 @@ static inline u32 i915_ggtt_offset(const struct i915_vma *vma)
 	return lower_32_bits(vma->node.start);
 }
 
+/* XXX inline spaghetti */
+static inline u32 i915_timeline_seqno_address(const struct i915_timeline *tl)
+{
+	GEM_BUG_ON(!tl->pin_count);
+	return i915_ggtt_offset(tl->hwsp_ggtt) + tl->hwsp_offset;
+}
+
 static inline u32 i915_ggtt_pin_bias(struct i915_vma *vma)
 {
 	return i915_vm_to_ggtt(vma->vm)->pin_bias;
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index a624e644fbd7..593928dd6bbe 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -827,10 +827,10 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
 	list_for_each_entry(rq, &engine->timeline.requests, link) {
 		GEM_BUG_ON(!rq->global_seqno);
 
-		if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &rq->fence.flags))
-			continue;
+		if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &rq->fence.flags))
+			dma_fence_set_error(&rq->fence, -EIO);
 
-		dma_fence_set_error(&rq->fence, -EIO);
+		i915_request_fake_complete(rq);
 	}
 
 	/* Flush the queued requests to the timeline list (for retiring). */
@@ -843,6 +843,7 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
 
 			dma_fence_set_error(&rq->fence, -EIO);
 			__i915_request_submit(rq);
+			i915_request_fake_complete(rq);
 		}
 
 		rb_erase_cached(&p->node, &execlists->queue);
@@ -2022,31 +2023,40 @@ static void gen8_emit_breadcrumb(struct i915_request *request, u32 *cs)
 	/* w/a: bit 5 needs to be zero for MI_FLUSH_DW address. */
 	BUILD_BUG_ON(I915_GEM_HWS_INDEX_ADDR & (1 << 5));
 
-	cs = gen8_emit_ggtt_write(cs, request->global_seqno,
+	cs = gen8_emit_ggtt_write(cs,
+				  request->fence.seqno,
+				  i915_timeline_seqno_address(request->timeline));
+
+	cs = gen8_emit_ggtt_write(cs,
+				  request->global_seqno,
 				  intel_hws_seqno_address(request->engine));
+
 	*cs++ = MI_USER_INTERRUPT;
 	*cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
+
 	request->tail = intel_ring_offset(request, cs);
 	assert_ring_tail_valid(request->ring, request->tail);
 
 	gen8_emit_wa_tail(request, cs);
 }
-static const int gen8_emit_breadcrumb_sz = 6 + WA_TAIL_DWORDS;
+static const int gen8_emit_breadcrumb_sz = 10 + WA_TAIL_DWORDS;
 
 static void gen8_emit_breadcrumb_rcs(struct i915_request *request, u32 *cs)
 {
-	/* We're using qword write, seqno should be aligned to 8 bytes. */
-	BUILD_BUG_ON(I915_GEM_HWS_INDEX & 1);
-
 	cs = gen8_emit_ggtt_write_rcs(cs,
-				      request->global_seqno,
-				      intel_hws_seqno_address(request->engine),
+				      request->fence.seqno,
+				      i915_timeline_seqno_address(request->timeline),
 				      PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
 				      PIPE_CONTROL_DEPTH_CACHE_FLUSH |
 				      PIPE_CONTROL_DC_FLUSH_ENABLE |
 				      PIPE_CONTROL_FLUSH_ENABLE |
 				      PIPE_CONTROL_CS_STALL);
 
+	cs = gen8_emit_ggtt_write_rcs(cs,
+				      request->global_seqno,
+				      intel_hws_seqno_address(request->engine),
+				      PIPE_CONTROL_CS_STALL);
+
 	*cs++ = MI_USER_INTERRUPT;
 	*cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
 
@@ -2055,7 +2065,7 @@ static void gen8_emit_breadcrumb_rcs(struct i915_request *request, u32 *cs)
 
 	gen8_emit_wa_tail(request, cs);
 }
-static const int gen8_emit_breadcrumb_rcs_sz = 8 + WA_TAIL_DWORDS;
+static const int gen8_emit_breadcrumb_rcs_sz = 14 + WA_TAIL_DWORDS;
 
 static int gen8_init_rcs_context(struct i915_request *rq)
 {
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 5887304bc3ae..bcc700e7037b 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -325,6 +325,12 @@ static void gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 		 PIPE_CONTROL_DC_FLUSH_ENABLE |
 		 PIPE_CONTROL_QW_WRITE |
 		 PIPE_CONTROL_CS_STALL);
+	*cs++ = i915_timeline_seqno_address(rq->timeline) |
+		PIPE_CONTROL_GLOBAL_GTT;
+	*cs++ = rq->fence.seqno;
+
+	*cs++ = GFX_OP_PIPE_CONTROL(4);
+	*cs++ = PIPE_CONTROL_QW_WRITE | PIPE_CONTROL_CS_STALL;
 	*cs++ = intel_hws_seqno_address(rq->engine) | PIPE_CONTROL_GLOBAL_GTT;
 	*cs++ = rq->global_seqno;
 
@@ -334,7 +340,7 @@ static void gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 	rq->tail = intel_ring_offset(rq, cs);
 	assert_ring_tail_valid(rq->ring, rq->tail);
 }
-static const int gen6_rcs_emit_breadcrumb_sz = 14;
+static const int gen6_rcs_emit_breadcrumb_sz = 18;
 
 static int
 gen7_render_ring_cs_stall_wa(struct i915_request *rq)
@@ -425,6 +431,13 @@ static void gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 		 PIPE_CONTROL_QW_WRITE |
 		 PIPE_CONTROL_GLOBAL_GTT_IVB |
 		 PIPE_CONTROL_CS_STALL);
+	*cs++ = i915_timeline_seqno_address(rq->timeline);
+	*cs++ = rq->fence.seqno;
+
+	*cs++ = GFX_OP_PIPE_CONTROL(4);
+	*cs++ = (PIPE_CONTROL_QW_WRITE |
+		 PIPE_CONTROL_GLOBAL_GTT_IVB |
+		 PIPE_CONTROL_CS_STALL);
 	*cs++ = intel_hws_seqno_address(rq->engine);
 	*cs++ = rq->global_seqno;
 
@@ -434,27 +447,37 @@ static void gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 	rq->tail = intel_ring_offset(rq, cs);
 	assert_ring_tail_valid(rq->ring, rq->tail);
 }
-static const int gen7_rcs_emit_breadcrumb_sz = 6;
+static const int gen7_rcs_emit_breadcrumb_sz = 10;
 
 static void gen6_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 {
-	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW;
-	*cs++ = intel_hws_seqno_address(rq->engine) | MI_FLUSH_DW_USE_GTT;
+	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
+	*cs++ = I915_GEM_HWS_SEQNO_ADDR | MI_FLUSH_DW_USE_GTT;
+	*cs++ = rq->fence.seqno;
+
+	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
+	*cs++ = I915_GEM_HWS_INDEX_ADDR | MI_FLUSH_DW_USE_GTT;
 	*cs++ = rq->global_seqno;
+
 	*cs++ = MI_USER_INTERRUPT;
+	*cs++ = MI_NOOP;
 
 	rq->tail = intel_ring_offset(rq, cs);
 	assert_ring_tail_valid(rq->ring, rq->tail);
 }
-static const int gen6_xcs_emit_breadcrumb_sz = 4;
+static const int gen6_xcs_emit_breadcrumb_sz = 8;
 
 #define GEN7_XCS_WA 32
 static void gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 {
 	int i;
 
-	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW;
-	*cs++ = intel_hws_seqno_address(rq->engine) | MI_FLUSH_DW_USE_GTT;
+	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
+	*cs++ = I915_GEM_HWS_SEQNO_ADDR | MI_FLUSH_DW_USE_GTT;
+	*cs++ = rq->fence.seqno;
+
+	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
+	*cs++ = I915_GEM_HWS_INDEX_ADDR | MI_FLUSH_DW_USE_GTT;
 	*cs++ = rq->global_seqno;
 
 	for (i = 0; i < GEN7_XCS_WA; i++) {
@@ -468,12 +491,11 @@ static void gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 	*cs++ = 0;
 
 	*cs++ = MI_USER_INTERRUPT;
-	*cs++ = MI_NOOP;
 
 	rq->tail = intel_ring_offset(rq, cs);
 	assert_ring_tail_valid(rq->ring, rq->tail);
 }
-static const int gen7_xcs_emit_breadcrumb_sz = 8 + GEN7_XCS_WA * 3;
+static const int gen7_xcs_emit_breadcrumb_sz = 10 + GEN7_XCS_WA * 3;
 #undef GEN7_XCS_WA
 
 static void set_hwstam(struct intel_engine_cs *engine, u32 mask)
@@ -733,7 +755,7 @@ static void reset_ring(struct intel_engine_cs *engine, bool stalled)
 	rq = NULL;
 	spin_lock_irqsave(&tl->lock, flags);
 	list_for_each_entry(pos, &tl->requests, link) {
-		if (!__i915_request_completed(pos, pos->global_seqno)) {
+		if (!i915_request_completed(pos)) {
 			rq = pos;
 			break;
 		}
@@ -875,11 +897,10 @@ static void cancel_requests(struct intel_engine_cs *engine)
 	list_for_each_entry(request, &engine->timeline.requests, link) {
 		GEM_BUG_ON(!request->global_seqno);
 
-		if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
-			     &request->fence.flags))
-			continue;
-
-		dma_fence_set_error(&request->fence, -EIO);
+		if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
+			      &request->fence.flags))
+			dma_fence_set_error(&request->fence, -EIO);
+		i915_request_fake_complete(request);
 	}
 
 	intel_write_status_page(engine,
@@ -903,27 +924,38 @@ static void i9xx_submit_request(struct i915_request *request)
 
 static void i9xx_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 {
+	GEM_BUG_ON(rq->timeline->hwsp_ggtt != rq->engine->status_page.vma);
+
 	*cs++ = MI_FLUSH;
 
+	*cs++ = MI_STORE_DWORD_INDEX;
+	*cs++ = I915_GEM_HWS_SEQNO_ADDR;
+	*cs++ = rq->fence.seqno;
+
 	*cs++ = MI_STORE_DWORD_INDEX;
 	*cs++ = I915_GEM_HWS_INDEX_ADDR;
 	*cs++ = rq->global_seqno;
 
 	*cs++ = MI_USER_INTERRUPT;
-	*cs++ = MI_NOOP;
 
 	rq->tail = intel_ring_offset(rq, cs);
 	assert_ring_tail_valid(rq->ring, rq->tail);
 }
-static const int i9xx_emit_breadcrumb_sz = 6;
+static const int i9xx_emit_breadcrumb_sz = 8;
 
 #define GEN5_WA_STORES 8 /* must be at least 1! */
 static void gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 {
 	int i;
 
+	GEM_BUG_ON(rq->timeline->hwsp_ggtt != rq->engine->status_page.vma);
+
 	*cs++ = MI_FLUSH;
 
+	*cs++ = MI_STORE_DWORD_INDEX;
+	*cs++ = I915_GEM_HWS_SEQNO_ADDR;
+	*cs++ = rq->fence.seqno;
+
 	BUILD_BUG_ON(GEN5_WA_STORES < 1);
 	for (i = 0; i < GEN5_WA_STORES; i++) {
 		*cs++ = MI_STORE_DWORD_INDEX;
@@ -932,11 +964,12 @@ static void gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 	}
 
 	*cs++ = MI_USER_INTERRUPT;
+	*cs++ = MI_NOOP;
 
 	rq->tail = intel_ring_offset(rq, cs);
 	assert_ring_tail_valid(rq->ring, rq->tail);
 }
-static const int gen5_emit_breadcrumb_sz = GEN5_WA_STORES * 3 + 2;
+static const int gen5_emit_breadcrumb_sz = GEN5_WA_STORES * 3 + 6;
 #undef GEN5_WA_STORES
 
 static void
@@ -1163,6 +1196,10 @@ int intel_ring_pin(struct intel_ring *ring)
 
 	GEM_BUG_ON(ring->vaddr);
 
+	ret = i915_timeline_pin(ring->timeline);
+	if (ret)
+		return ret;
+
 	flags = PIN_GLOBAL;
 
 	/* Ring wraparound at offset 0 sometimes hangs. No idea why. */
@@ -1179,28 +1216,32 @@ int intel_ring_pin(struct intel_ring *ring)
 		else
 			ret = i915_gem_object_set_to_cpu_domain(vma->obj, true);
 		if (unlikely(ret))
-			return ret;
+			goto unpin_timeline;
 	}
 
 	ret = i915_vma_pin(vma, 0, 0, flags);
 	if (unlikely(ret))
-		return ret;
+		goto unpin_timeline;
 
 	if (i915_vma_is_map_and_fenceable(vma))
 		addr = (void __force *)i915_vma_pin_iomap(vma);
 	else
 		addr = i915_gem_object_pin_map(vma->obj, map);
-	if (IS_ERR(addr))
-		goto err;
+	if (IS_ERR(addr)) {
+		ret = PTR_ERR(addr);
+		goto unpin_ring;
+	}
 
 	vma->obj->pin_global++;
 
 	ring->vaddr = addr;
 	return 0;
 
-err:
+unpin_ring:
 	i915_vma_unpin(vma);
-	return PTR_ERR(addr);
+unpin_timeline:
+	i915_timeline_unpin(ring->timeline);
+	return ret;
 }
 
 void intel_ring_reset(struct intel_ring *ring, u32 tail)
@@ -1229,6 +1270,8 @@ void intel_ring_unpin(struct intel_ring *ring)
 
 	ring->vma->obj->pin_global--;
 	i915_vma_unpin(ring->vma);
+
+	i915_timeline_unpin(ring->timeline);
 }
 
 static struct i915_vma *
diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
index acd27c7e807b..b4b61056b227 100644
--- a/drivers/gpu/drm/i915/selftests/mock_engine.c
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
@@ -79,6 +79,7 @@ static void advance(struct mock_engine *engine,
 		    struct mock_request *request)
 {
 	list_del_init(&request->link);
+	i915_request_fake_complete(&request->base);
 	mock_seqno_advance(&engine->base, request->base.global_seqno);
 }
 
@@ -253,16 +254,13 @@ void mock_engine_flush(struct intel_engine_cs *engine)
 	del_timer_sync(&mock->hw_delay);
 
 	spin_lock_irq(&mock->hw_lock);
-	list_for_each_entry_safe(request, rn, &mock->hw_queue, link) {
-		list_del_init(&request->link);
-		mock_seqno_advance(&mock->base, request->base.global_seqno);
-	}
+	list_for_each_entry_safe(request, rn, &mock->hw_queue, link)
+		advance(mock, request);
 	spin_unlock_irq(&mock->hw_lock);
 }
 
 void mock_engine_reset(struct intel_engine_cs *engine)
 {
-	intel_write_status_page(engine, I915_GEM_HWS_INDEX, 0);
 }
 
 void mock_engine_free(struct intel_engine_cs *engine)
-- 
2.20.1

_______________________________________________
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^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 20/23] drm/i915: Identify active requests
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (18 preceding siblings ...)
  2019-01-17 14:35 ` [PATCH 19/23] drm/i915: Track the context's seqno in its own timeline HWSP Chris Wilson
@ 2019-01-17 14:35 ` Chris Wilson
  2019-01-17 14:35 ` [PATCH 21/23] drm/i915: Remove the intel_engine_notify tracepoint Chris Wilson
                   ` (7 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:35 UTC (permalink / raw)
  To: intel-gfx

To allow requests to forgo a common execution timeline, one question we
need to be able to answer is "is this request running?". To track
whether a request has started on HW, we can emit a breadcrumb at the
beginning of the request and check its timeline's HWSP to see if the
breadcrumb has advanced past the start of this request. (This is in
contrast to the global timeline where we need only ask if we are on the
global timeline and if the timeline has advanced past the end of the
previous request.)

There is still confusion from a preempted request, which has already
started but relinquished the HW to a high priority request. For the
common case, this discrepancy should be negligible. However, for
identification of hung requests, knowing which one was running at the
time of the hang will be much more important.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_request.c     |  1 +
 drivers/gpu/drm/i915/i915_request.h     |  1 +
 drivers/gpu/drm/i915/i915_timeline.c    |  1 +
 drivers/gpu/drm/i915/i915_timeline.h    |  2 ++
 drivers/gpu/drm/i915/intel_engine_cs.c  |  4 +++-
 drivers/gpu/drm/i915/intel_lrc.c        | 23 +++++++++++++++++++++++
 drivers/gpu/drm/i915/intel_ringbuffer.c |  2 ++
 7 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 0d7b71aff28f..f61cc5c1bf08 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -332,6 +332,7 @@ void i915_request_retire_upto(struct i915_request *rq)
 
 static u32 timeline_get_seqno(struct i915_timeline *tl)
 {
+	tl->seqno += tl->has_initial_breadcrumb;
 	return ++tl->seqno;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h
index a16a3b7f7d92..83ce982dcbd9 100644
--- a/drivers/gpu/drm/i915/i915_request.h
+++ b/drivers/gpu/drm/i915/i915_request.h
@@ -324,6 +324,7 @@ static inline u32 hwsp_seqno(const struct i915_request *rq)
  */
 static inline bool i915_request_started(const struct i915_request *rq)
 {
+	/* Remember: started but may have since been preempted! */
 	return i915_seqno_passed(hwsp_seqno(rq), rq->fence.seqno - 1);
 }
 
diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
index 64bb1ce24318..e4c78ea8c73c 100644
--- a/drivers/gpu/drm/i915/i915_timeline.c
+++ b/drivers/gpu/drm/i915/i915_timeline.c
@@ -120,6 +120,7 @@ int i915_timeline_init(struct drm_i915_private *i915,
 	timeline->i915 = i915;
 	timeline->name = name;
 	timeline->pin_count = 0;
+	timeline->has_initial_breadcrumb = !global_hwsp;
 
 	if (global_hwsp) {
 		timeline->hwsp_ggtt = i915_vma_get(global_hwsp);
diff --git a/drivers/gpu/drm/i915/i915_timeline.h b/drivers/gpu/drm/i915/i915_timeline.h
index 0c3739d53d79..421eb34568de 100644
--- a/drivers/gpu/drm/i915/i915_timeline.h
+++ b/drivers/gpu/drm/i915/i915_timeline.h
@@ -47,6 +47,8 @@ struct i915_timeline {
 	struct i915_vma *hwsp_ggtt;
 	u32 hwsp_offset;
 
+	bool has_initial_breadcrumb;
+
 	/**
 	 * List of breadcrumbs associated with GPU requests currently
 	 * outstanding.
diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index c850d131d8c3..ae455b874c9f 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -1239,7 +1239,9 @@ static void print_request(struct drm_printer *m,
 	drm_printf(m, "%s%x%s [%llx:%llx]%s @ %dms: %s\n",
 		   prefix,
 		   rq->global_seqno,
-		   i915_request_completed(rq) ? "!" : "",
+		   i915_request_completed(rq) ? "!" :
+		   i915_request_started(rq) ? "*" :
+		   "",
 		   rq->fence.context, rq->fence.seqno,
 		   buf,
 		   jiffies_to_msecs(jiffies - rq->emitted_jiffies),
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 593928dd6bbe..87b334a29836 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1263,6 +1263,25 @@ execlists_context_pin(struct intel_engine_cs *engine,
 	return __execlists_context_pin(engine, ctx, ce);
 }
 
+static int emit_initial_breadcrumb(struct i915_request *rq)
+{
+	u32 *cs;
+
+	GEM_BUG_ON(!rq->timeline->has_initial_breadcrumb);
+
+	cs = intel_ring_begin(rq, 4);
+	if (IS_ERR(cs))
+		return PTR_ERR(cs);
+
+	*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+	*cs++ = i915_timeline_seqno_address(rq->timeline);
+	*cs++ = 0;
+	*cs++ = rq->fence.seqno - 1;
+
+	intel_ring_advance(rq, cs);
+	return 0;
+}
+
 static int emit_pdps(struct i915_request *rq)
 {
 	const struct intel_engine_cs * const engine = rq->engine;
@@ -1337,6 +1356,10 @@ static int execlists_request_alloc(struct i915_request *request)
 	 * to cancel/unwind this request now.
 	 */
 
+	ret = emit_initial_breadcrumb(request);
+	if (ret)
+		return ret;
+
 	/* Unconditionally invalidate GPU caches and TLBs. */
 	if (i915_vm_is_48bit(&request->gem_context->ppgtt->vm))
 		ret = request->engine->emit_flush(request, EMIT_INVALIDATE);
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index bcc700e7037b..2b4beb15a271 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1593,6 +1593,7 @@ static int intel_init_ring_buffer(struct intel_engine_cs *engine)
 		err = PTR_ERR(timeline);
 		goto err;
 	}
+	GEM_BUG_ON(timeline->has_initial_breadcrumb);
 
 	ring = intel_engine_create_ring(engine, timeline, 32 * PAGE_SIZE);
 	i915_timeline_put(timeline);
@@ -1946,6 +1947,7 @@ static int ring_request_alloc(struct i915_request *request)
 	int ret;
 
 	GEM_BUG_ON(!request->hw_context->pin_count);
+	GEM_BUG_ON(request->timeline->has_initial_breadcrumb);
 
 	/*
 	 * Flush enough space to reduce the likelihood of waiting after
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 21/23] drm/i915: Remove the intel_engine_notify tracepoint
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (19 preceding siblings ...)
  2019-01-17 14:35 ` [PATCH 20/23] drm/i915: Identify active requests Chris Wilson
@ 2019-01-17 14:35 ` Chris Wilson
  2019-01-17 14:35 ` [PATCH 22/23] drm/i915: Replace global breadcrumbs with per-context interrupt tracking Chris Wilson
                   ` (6 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:35 UTC (permalink / raw)
  To: intel-gfx

The global seqno is defunct and so we have no meaningful indicator of
forward progress for an engine. You need to listen to the request
signaling tracepoints instead.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_irq.c   |  2 --
 drivers/gpu/drm/i915/i915_trace.h | 25 -------------------------
 2 files changed, 27 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 1abfc3fa76ad..8da5816e2854 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1210,8 +1210,6 @@ static void notify_ring(struct intel_engine_cs *engine)
 		wake_up_process(tsk);
 
 	rcu_read_unlock();
-
-	trace_intel_engine_notify(engine, wait);
 }
 
 static void vlv_c0_read(struct drm_i915_private *dev_priv,
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index 33d90eca9cdd..cb5bc65d575d 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -750,31 +750,6 @@ trace_i915_request_out(struct i915_request *rq)
 #endif
 #endif
 
-TRACE_EVENT(intel_engine_notify,
-	    TP_PROTO(struct intel_engine_cs *engine, bool waiters),
-	    TP_ARGS(engine, waiters),
-
-	    TP_STRUCT__entry(
-			     __field(u32, dev)
-			     __field(u16, class)
-			     __field(u16, instance)
-			     __field(u32, seqno)
-			     __field(bool, waiters)
-			     ),
-
-	    TP_fast_assign(
-			   __entry->dev = engine->i915->drm.primary->index;
-			   __entry->class = engine->uabi_class;
-			   __entry->instance = engine->instance;
-			   __entry->seqno = intel_engine_get_seqno(engine);
-			   __entry->waiters = waiters;
-			   ),
-
-	    TP_printk("dev=%u, engine=%u:%u, seqno=%u, waiters=%u",
-		      __entry->dev, __entry->class, __entry->instance,
-		      __entry->seqno, __entry->waiters)
-);
-
 DEFINE_EVENT(i915_request, i915_request_retire,
 	    TP_PROTO(struct i915_request *rq),
 	    TP_ARGS(rq)
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 22/23] drm/i915: Replace global breadcrumbs with per-context interrupt tracking
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (20 preceding siblings ...)
  2019-01-17 14:35 ` [PATCH 21/23] drm/i915: Remove the intel_engine_notify tracepoint Chris Wilson
@ 2019-01-17 14:35 ` Chris Wilson
  2019-01-17 14:35 ` [PATCH 23/23] drm/i915: Drop fake breadcrumb irq Chris Wilson
                   ` (5 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:35 UTC (permalink / raw)
  To: intel-gfx

A few years ago, see commit 688e6c725816 ("drm/i915: Slaughter the
thundering i915_wait_request herd"), the issue of handling multiple
clients waiting in parallel was brought to our attention. The
requirement was that every client should be woken immediately upon its
request being signaled, without incurring any cpu overhead.

To handle certain fragility of our hw meant that we could not do a
simple check inside the irq handler (some generations required almost
unbounded delays before we could be sure of seqno coherency) and so
request completion checking required delegation.

Before commit 688e6c725816, the solution was simple. Every client waking
on a request would be woken on every interrupt and each would do a
heavyweight check to see if their request was complete. Commit
688e6c725816 introduced an rbtree so that only the earliest waiter on
the global timeline would woken, and would wake the next and so on.
(Along with various complications to handle requests being reordered
along the global timeline, and also a requirement for kthread to provide
a delegate for fence signaling that had no process context.)

The global rbtree depends on knowing the execution timeline (and global
seqno). Without knowing that order, we must instead check all contexts
queued to the HW to see which may have advanced. We trim that list by
only checking queued contexts that are being waited on, but still we
keep a list of all active contexts and their active signalers that we
inspect from inside the irq handler. By moving the waiters onto the fence
signal list, we can combine the client wakeup with the dma_fence
signaling (a dramatic reduction in complexity, but does require the HW
being coherent, the seqno must be visible from the cpu before the
interrupt is raised - we keep a timer backup just in case).

Having previously fixed all the issues with irq-seqno serialisation (by
inserting delays onto the GPU after each request instead of random delays
on the CPU after each interrupt), we can rely on the seqno state to
perfom direct wakeups from the interrupt handler. This allows us to
preserve our single context switch behaviour of the current routine,
with the only downside that we lose the RT priority sorting of wakeups.
In general, direct wakeup latency of multiple clients is about the same
(about 10% better in most cases) with a reduction in total CPU time spent
in the waiter (about 20-50% depending on gen). Average herd behaviour is
improved, but at the cost of not delegating wakeups on task_prio.

References: 688e6c725816 ("drm/i915: Slaughter the thundering i915_wait_request herd")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_debugfs.c           |  28 +-
 drivers/gpu/drm/i915/i915_gem_context.c       |   2 +
 drivers/gpu/drm/i915/i915_gem_context.h       |   2 +
 drivers/gpu/drm/i915/i915_gpu_error.c         |  73 --
 drivers/gpu/drm/i915/i915_gpu_error.h         |   8 -
 drivers/gpu/drm/i915/i915_irq.c               |  88 +-
 drivers/gpu/drm/i915/i915_request.c           | 128 +--
 drivers/gpu/drm/i915/i915_request.h           |  22 +-
 drivers/gpu/drm/i915/i915_reset.c             |  13 +-
 drivers/gpu/drm/i915/intel_breadcrumbs.c      | 809 +++++-------------
 drivers/gpu/drm/i915/intel_engine_cs.c        |  34 +-
 drivers/gpu/drm/i915/intel_ringbuffer.c       |   6 +-
 drivers/gpu/drm/i915/intel_ringbuffer.h       |  95 +-
 .../drm/i915/selftests/i915_mock_selftests.h  |   1 -
 drivers/gpu/drm/i915/selftests/i915_request.c | 398 +++++++++
 drivers/gpu/drm/i915/selftests/igt_spinner.c  |   5 -
 .../drm/i915/selftests/intel_breadcrumbs.c    | 470 ----------
 .../gpu/drm/i915/selftests/intel_hangcheck.c  |   2 +-
 drivers/gpu/drm/i915/selftests/lib_sw_fence.c |  54 ++
 drivers/gpu/drm/i915/selftests/lib_sw_fence.h |   3 +
 drivers/gpu/drm/i915/selftests/mock_context.c |   2 +
 drivers/gpu/drm/i915/selftests/mock_engine.c  |  26 +-
 drivers/gpu/drm/i915/selftests/mock_engine.h  |   6 -
 23 files changed, 782 insertions(+), 1493 deletions(-)
 delete mode 100644 drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index d052329c2319..a8830d7d1617 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1315,29 +1315,16 @@ static int i915_hangcheck_info(struct seq_file *m, void *unused)
 	seq_printf(m, "GT active? %s\n", yesno(dev_priv->gt.awake));
 
 	for_each_engine(engine, dev_priv, id) {
-		struct intel_breadcrumbs *b = &engine->breadcrumbs;
-		struct rb_node *rb;
-
 		seq_printf(m, "%s:\n", engine->name);
 		seq_printf(m, "\tseqno = %x [current %x, last %x]\n",
 			   engine->hangcheck.seqno, seqno[id],
 			   intel_engine_last_submit(engine));
-		seq_printf(m, "\twaiters? %s, fake irq active? %s, stalled? %s, wedged? %s\n",
-			   yesno(intel_engine_has_waiter(engine)),
+		seq_printf(m, "\tfake irq active? %s, stalled? %s, wedged? %s\n",
 			   yesno(test_bit(engine->id,
 					  &dev_priv->gpu_error.missed_irq_rings)),
 			   yesno(engine->hangcheck.stalled),
 			   yesno(engine->hangcheck.wedged));
 
-		spin_lock_irq(&b->rb_lock);
-		for (rb = rb_first(&b->waiters); rb; rb = rb_next(rb)) {
-			struct intel_wait *w = rb_entry(rb, typeof(*w), node);
-
-			seq_printf(m, "\t%s [%d] waiting for %x\n",
-				   w->tsk->comm, w->tsk->pid, w->seqno);
-		}
-		spin_unlock_irq(&b->rb_lock);
-
 		seq_printf(m, "\tACTHD = 0x%08llx [current 0x%08llx]\n",
 			   (long long)engine->hangcheck.acthd,
 			   (long long)acthd[id]);
@@ -2026,18 +2013,6 @@ static int i915_swizzle_info(struct seq_file *m, void *data)
 	return 0;
 }
 
-static int count_irq_waiters(struct drm_i915_private *i915)
-{
-	struct intel_engine_cs *engine;
-	enum intel_engine_id id;
-	int count = 0;
-
-	for_each_engine(engine, i915, id)
-		count += intel_engine_has_waiter(engine);
-
-	return count;
-}
-
 static const char *rps_power_to_str(unsigned int power)
 {
 	static const char * const strings[] = {
@@ -2077,7 +2052,6 @@ static int i915_rps_boost_info(struct seq_file *m, void *data)
 	seq_printf(m, "RPS enabled? %d\n", rps->enabled);
 	seq_printf(m, "GPU busy? %s [%d requests]\n",
 		   yesno(dev_priv->gt.awake), dev_priv->gt.active_requests);
-	seq_printf(m, "CPU waiting? %d\n", count_irq_waiters(dev_priv));
 	seq_printf(m, "Boosts outstanding? %d\n",
 		   atomic_read(&rps->num_waiters));
 	seq_printf(m, "Interactive? %d\n", READ_ONCE(rps->power.interactive));
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 5933adbe3d99..054d3e1bfe00 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -342,6 +342,8 @@ __create_hw_context(struct drm_i915_private *dev_priv,
 		struct intel_context *ce = &ctx->__engine[n];
 
 		ce->gem_context = ctx;
+		INIT_LIST_HEAD(&ce->signal_link);
+		INIT_LIST_HEAD(&ce->signals);
 	}
 
 	INIT_RADIX_TREE(&ctx->handles_vma, GFP_KERNEL);
diff --git a/drivers/gpu/drm/i915/i915_gem_context.h b/drivers/gpu/drm/i915/i915_gem_context.h
index f6d870b1f73e..e5eca29cd373 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.h
+++ b/drivers/gpu/drm/i915/i915_gem_context.h
@@ -164,6 +164,8 @@ struct i915_gem_context {
 	struct intel_context {
 		struct i915_gem_context *gem_context;
 		struct intel_engine_cs *active;
+		struct list_head signal_link;
+		struct list_head signals;
 		struct i915_vma *state;
 		struct intel_ring *ring;
 		u32 *lrc_reg_state;
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 5914ed5e3735..c6057126bb53 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -530,7 +530,6 @@ static void error_print_engine(struct drm_i915_error_state_buf *m,
 	}
 	err_printf(m, "  seqno: 0x%08x\n", ee->seqno);
 	err_printf(m, "  last_seqno: 0x%08x\n", ee->last_seqno);
-	err_printf(m, "  waiting: %s\n", yesno(ee->waiting));
 	err_printf(m, "  ring->head: 0x%08x\n", ee->cpu_ring_head);
 	err_printf(m, "  ring->tail: 0x%08x\n", ee->cpu_ring_tail);
 	err_printf(m, "  hangcheck stall: %s\n", yesno(ee->hangcheck_stalled));
@@ -807,21 +806,6 @@ static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
 						    error->epoch);
 		}
 
-		if (IS_ERR(ee->waiters)) {
-			err_printf(m, "%s --- ? waiters [unable to acquire spinlock]\n",
-				   m->i915->engine[i]->name);
-		} else if (ee->num_waiters) {
-			err_printf(m, "%s --- %d waiters\n",
-				   m->i915->engine[i]->name,
-				   ee->num_waiters);
-			for (j = 0; j < ee->num_waiters; j++) {
-				err_printf(m, " seqno 0x%08x for %s [%d]\n",
-					   ee->waiters[j].seqno,
-					   ee->waiters[j].comm,
-					   ee->waiters[j].pid);
-			}
-		}
-
 		print_error_obj(m, m->i915->engine[i],
 				"ringbuffer", ee->ringbuffer);
 
@@ -1003,8 +987,6 @@ void __i915_gpu_state_free(struct kref *error_ref)
 		i915_error_object_free(ee->wa_ctx);
 
 		kfree(ee->requests);
-		if (!IS_ERR_OR_NULL(ee->waiters))
-			kfree(ee->waiters);
 	}
 
 	for (i = 0; i < ARRAY_SIZE(error->active_bo); i++)
@@ -1211,59 +1193,6 @@ static void gen6_record_semaphore_state(struct intel_engine_cs *engine,
 			I915_READ(RING_SYNC_2(engine->mmio_base));
 }
 
-static void error_record_engine_waiters(struct intel_engine_cs *engine,
-					struct drm_i915_error_engine *ee)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	struct drm_i915_error_waiter *waiter;
-	struct rb_node *rb;
-	int count;
-
-	ee->num_waiters = 0;
-	ee->waiters = NULL;
-
-	if (RB_EMPTY_ROOT(&b->waiters))
-		return;
-
-	if (!spin_trylock_irq(&b->rb_lock)) {
-		ee->waiters = ERR_PTR(-EDEADLK);
-		return;
-	}
-
-	count = 0;
-	for (rb = rb_first(&b->waiters); rb != NULL; rb = rb_next(rb))
-		count++;
-	spin_unlock_irq(&b->rb_lock);
-
-	waiter = NULL;
-	if (count)
-		waiter = kmalloc_array(count,
-				       sizeof(struct drm_i915_error_waiter),
-				       GFP_ATOMIC);
-	if (!waiter)
-		return;
-
-	if (!spin_trylock_irq(&b->rb_lock)) {
-		kfree(waiter);
-		ee->waiters = ERR_PTR(-EDEADLK);
-		return;
-	}
-
-	ee->waiters = waiter;
-	for (rb = rb_first(&b->waiters); rb; rb = rb_next(rb)) {
-		struct intel_wait *w = rb_entry(rb, typeof(*w), node);
-
-		strcpy(waiter->comm, w->tsk->comm);
-		waiter->pid = w->tsk->pid;
-		waiter->seqno = w->seqno;
-		waiter++;
-
-		if (++ee->num_waiters == count)
-			break;
-	}
-	spin_unlock_irq(&b->rb_lock);
-}
-
 static void error_record_engine_registers(struct i915_gpu_state *error,
 					  struct intel_engine_cs *engine,
 					  struct drm_i915_error_engine *ee)
@@ -1299,7 +1228,6 @@ static void error_record_engine_registers(struct i915_gpu_state *error,
 
 	intel_engine_get_instdone(engine, &ee->instdone);
 
-	ee->waiting = intel_engine_has_waiter(engine);
 	ee->instpm = I915_READ(RING_INSTPM(engine->mmio_base));
 	ee->acthd = intel_engine_get_active_head(engine);
 	ee->seqno = intel_engine_get_seqno(engine);
@@ -1549,7 +1477,6 @@ static void gem_record_rings(struct i915_gpu_state *error)
 		ee->engine_id = i;
 
 		error_record_engine_registers(error, engine, ee);
-		error_record_engine_waiters(engine, ee);
 		error_record_engine_execlists(engine, ee);
 
 		request = i915_gem_find_active_request(engine);
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.h b/drivers/gpu/drm/i915/i915_gpu_error.h
index 733723e1ea03..cb6a6add543e 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.h
+++ b/drivers/gpu/drm/i915/i915_gpu_error.h
@@ -82,8 +82,6 @@ struct i915_gpu_state {
 		int engine_id;
 		/* Software tracked state */
 		bool idle;
-		bool waiting;
-		int num_waiters;
 		unsigned long hangcheck_timestamp;
 		bool hangcheck_stalled;
 		enum intel_engine_hangcheck_action hangcheck_action;
@@ -161,12 +159,6 @@ struct i915_gpu_state {
 		} *requests, execlist[EXECLIST_MAX_PORTS];
 		unsigned int num_ports;
 
-		struct drm_i915_error_waiter {
-			char comm[TASK_COMM_LEN];
-			pid_t pid;
-			u32 seqno;
-		} *waiters;
-
 		struct {
 			u32 gfx_mode;
 			union {
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 8da5816e2854..7669b1caeef0 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -28,9 +28,10 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#include <linux/sysrq.h>
-#include <linux/slab.h>
 #include <linux/circ_buf.h>
+#include <linux/slab.h>
+#include <linux/sysrq.h>
+
 #include <drm/i915_drm.h>
 #include "i915_drv.h"
 #include "i915_trace.h"
@@ -1151,67 +1152,6 @@ static void ironlake_rps_change_irq_handler(struct drm_i915_private *dev_priv)
 	return;
 }
 
-static void notify_ring(struct intel_engine_cs *engine)
-{
-	const u32 seqno = intel_engine_get_seqno(engine);
-	struct i915_request *rq = NULL;
-	struct task_struct *tsk = NULL;
-	struct intel_wait *wait;
-
-	if (unlikely(!engine->breadcrumbs.irq_armed))
-		return;
-
-	rcu_read_lock();
-
-	spin_lock(&engine->breadcrumbs.irq_lock);
-	wait = engine->breadcrumbs.irq_wait;
-	if (wait) {
-		/*
-		 * We use a callback from the dma-fence to submit
-		 * requests after waiting on our own requests. To
-		 * ensure minimum delay in queuing the next request to
-		 * hardware, signal the fence now rather than wait for
-		 * the signaler to be woken up. We still wake up the
-		 * waiter in order to handle the irq-seqno coherency
-		 * issues (we may receive the interrupt before the
-		 * seqno is written, see __i915_request_irq_complete())
-		 * and to handle coalescing of multiple seqno updates
-		 * and many waiters.
-		 */
-		if (i915_seqno_passed(seqno, wait->seqno)) {
-			struct i915_request *waiter = wait->request;
-
-			if (waiter &&
-			    !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
-				      &waiter->fence.flags) &&
-			    intel_wait_check_request(wait, waiter))
-				rq = i915_request_get(waiter);
-
-			tsk = wait->tsk;
-		}
-
-		engine->breadcrumbs.irq_count++;
-	} else {
-		if (engine->breadcrumbs.irq_armed)
-			__intel_engine_disarm_breadcrumbs(engine);
-	}
-	spin_unlock(&engine->breadcrumbs.irq_lock);
-
-	if (rq) {
-		spin_lock(&rq->lock);
-		dma_fence_signal_locked(&rq->fence);
-		GEM_BUG_ON(!i915_request_completed(rq));
-		spin_unlock(&rq->lock);
-
-		i915_request_put(rq);
-	}
-
-	if (tsk && tsk->state & TASK_NORMAL)
-		wake_up_process(tsk);
-
-	rcu_read_unlock();
-}
-
 static void vlv_c0_read(struct drm_i915_private *dev_priv,
 			struct intel_rps_ei *ei)
 {
@@ -1456,20 +1396,20 @@ static void ilk_gt_irq_handler(struct drm_i915_private *dev_priv,
 			       u32 gt_iir)
 {
 	if (gt_iir & GT_RENDER_USER_INTERRUPT)
-		notify_ring(dev_priv->engine[RCS]);
+		intel_engine_breadcrumbs_irq(dev_priv->engine[RCS]);
 	if (gt_iir & ILK_BSD_USER_INTERRUPT)
-		notify_ring(dev_priv->engine[VCS]);
+		intel_engine_breadcrumbs_irq(dev_priv->engine[VCS]);
 }
 
 static void snb_gt_irq_handler(struct drm_i915_private *dev_priv,
 			       u32 gt_iir)
 {
 	if (gt_iir & GT_RENDER_USER_INTERRUPT)
-		notify_ring(dev_priv->engine[RCS]);
+		intel_engine_breadcrumbs_irq(dev_priv->engine[RCS]);
 	if (gt_iir & GT_BSD_USER_INTERRUPT)
-		notify_ring(dev_priv->engine[VCS]);
+		intel_engine_breadcrumbs_irq(dev_priv->engine[VCS]);
 	if (gt_iir & GT_BLT_USER_INTERRUPT)
-		notify_ring(dev_priv->engine[BCS]);
+		intel_engine_breadcrumbs_irq(dev_priv->engine[BCS]);
 
 	if (gt_iir & (GT_BLT_CS_ERROR_INTERRUPT |
 		      GT_BSD_CS_ERROR_INTERRUPT |
@@ -1489,7 +1429,7 @@ gen8_cs_irq_handler(struct intel_engine_cs *engine, u32 iir)
 		tasklet = true;
 
 	if (iir & GT_RENDER_USER_INTERRUPT) {
-		notify_ring(engine);
+		intel_engine_breadcrumbs_irq(engine);
 		tasklet |= USES_GUC_SUBMISSION(engine->i915);
 	}
 
@@ -1835,7 +1775,7 @@ static void gen6_rps_irq_handler(struct drm_i915_private *dev_priv, u32 pm_iir)
 
 	if (HAS_VEBOX(dev_priv)) {
 		if (pm_iir & PM_VEBOX_USER_INTERRUPT)
-			notify_ring(dev_priv->engine[VECS]);
+			intel_engine_breadcrumbs_irq(dev_priv->engine[VECS]);
 
 		if (pm_iir & PM_VEBOX_CS_ERROR_INTERRUPT)
 			DRM_DEBUG("Command parser error, pm_iir 0x%08x\n", pm_iir);
@@ -4258,7 +4198,7 @@ static irqreturn_t i8xx_irq_handler(int irq, void *arg)
 		I915_WRITE16(IIR, iir);
 
 		if (iir & I915_USER_INTERRUPT)
-			notify_ring(dev_priv->engine[RCS]);
+			intel_engine_breadcrumbs_irq(dev_priv->engine[RCS]);
 
 		if (iir & I915_MASTER_ERROR_INTERRUPT)
 			i8xx_error_irq_handler(dev_priv, eir, eir_stuck);
@@ -4366,7 +4306,7 @@ static irqreturn_t i915_irq_handler(int irq, void *arg)
 		I915_WRITE(IIR, iir);
 
 		if (iir & I915_USER_INTERRUPT)
-			notify_ring(dev_priv->engine[RCS]);
+			intel_engine_breadcrumbs_irq(dev_priv->engine[RCS]);
 
 		if (iir & I915_MASTER_ERROR_INTERRUPT)
 			i9xx_error_irq_handler(dev_priv, eir, eir_stuck);
@@ -4511,10 +4451,10 @@ static irqreturn_t i965_irq_handler(int irq, void *arg)
 		I915_WRITE(IIR, iir);
 
 		if (iir & I915_USER_INTERRUPT)
-			notify_ring(dev_priv->engine[RCS]);
+			intel_engine_breadcrumbs_irq(dev_priv->engine[RCS]);
 
 		if (iir & I915_BSD_USER_INTERRUPT)
-			notify_ring(dev_priv->engine[VCS]);
+			intel_engine_breadcrumbs_irq(dev_priv->engine[VCS]);
 
 		if (iir & I915_MASTER_ERROR_INTERRUPT)
 			i9xx_error_irq_handler(dev_priv, eir, eir_stuck);
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index f61cc5c1bf08..5ad14409b52d 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -60,7 +60,7 @@ static bool i915_fence_signaled(struct dma_fence *fence)
 
 static bool i915_fence_enable_signaling(struct dma_fence *fence)
 {
-	return intel_engine_enable_signaling(to_request(fence), true);
+	return intel_engine_enable_signaling(to_request(fence));
 }
 
 static signed long i915_fence_wait(struct dma_fence *fence,
@@ -370,9 +370,11 @@ void __i915_request_submit(struct i915_request *request)
 
 	/* We may be recursing from the signal callback of another i915 fence */
 	spin_lock_nested(&request->lock, SINGLE_DEPTH_NESTING);
+	set_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags);
 	request->global_seqno = seqno;
-	if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &request->fence.flags))
-		intel_engine_enable_signaling(request, false);
+	if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &request->fence.flags) &&
+	    !intel_engine_enable_signaling(request))
+		intel_engine_queue_breadcrumbs(engine);
 	spin_unlock(&request->lock);
 
 	engine->emit_breadcrumb(request,
@@ -382,8 +384,6 @@ void __i915_request_submit(struct i915_request *request)
 	move_to_timeline(request, &engine->timeline);
 
 	trace_i915_request_execute(request);
-
-	wake_up_all(&request->execute);
 }
 
 void i915_request_submit(struct i915_request *request)
@@ -427,6 +427,7 @@ void __i915_request_unsubmit(struct i915_request *request)
 	request->global_seqno = 0;
 	if (test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &request->fence.flags))
 		intel_engine_cancel_signaling(request);
+	clear_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags);
 	spin_unlock(&request->lock);
 
 	/* Transfer back from the global per-engine timeline to per-context */
@@ -626,13 +627,11 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx)
 
 	/* We bump the ref for the fence chain */
 	i915_sw_fence_init(&i915_request_get(rq)->submit, submit_notify);
-	init_waitqueue_head(&rq->execute);
 
 	i915_sched_node_init(&rq->sched);
 
 	/* No zalloc, must clear what we need by hand */
 	rq->global_seqno = 0;
-	rq->signaling.wait.seqno = 0;
 	rq->file_priv = NULL;
 	rq->batch = NULL;
 	rq->capture_list = NULL;
@@ -1023,13 +1022,10 @@ static bool busywait_stop(unsigned long timeout, unsigned int cpu)
 	return this_cpu != cpu;
 }
 
-static bool __i915_spin_request(const struct i915_request *rq,
-				u32 seqno, int state, unsigned long timeout_us)
+static bool __i915_spin_request(const struct i915_request * const rq,
+				int state, unsigned long timeout_us)
 {
-	struct intel_engine_cs *engine = rq->engine;
-	unsigned int irq, cpu;
-
-	GEM_BUG_ON(!seqno);
+	unsigned int cpu;
 
 	/*
 	 * Only wait for the request if we know it is likely to complete.
@@ -1042,7 +1038,7 @@ static bool __i915_spin_request(const struct i915_request *rq,
 	 * it is a fair assumption that it will not complete within our
 	 * relatively short timeout.
 	 */
-	if (!intel_engine_has_started(engine, seqno))
+	if (!i915_request_started(rq))
 		return false;
 
 	/*
@@ -1056,20 +1052,10 @@ static bool __i915_spin_request(const struct i915_request *rq,
 	 * takes to sleep on a request, on the order of a microsecond.
 	 */
 
-	irq = READ_ONCE(engine->breadcrumbs.irq_count);
 	timeout_us += local_clock_us(&cpu);
 	do {
-		if (intel_engine_has_completed(engine, seqno))
-			return seqno == i915_request_global_seqno(rq);
-
-		/*
-		 * Seqno are meant to be ordered *before* the interrupt. If
-		 * we see an interrupt without a corresponding seqno advance,
-		 * assume we won't see one in the near future but require
-		 * the engine->seqno_barrier() to fixup coherency.
-		 */
-		if (READ_ONCE(engine->breadcrumbs.irq_count) != irq)
-			break;
+		if (i915_request_completed(rq))
+			return true;
 
 		if (signal_pending_state(state, current))
 			break;
@@ -1083,6 +1069,18 @@ static bool __i915_spin_request(const struct i915_request *rq,
 	return false;
 }
 
+struct request_wait {
+	struct dma_fence_cb cb;
+	struct task_struct *tsk;
+};
+
+static void request_wait_wake(struct dma_fence *fence, struct dma_fence_cb *cb)
+{
+	struct request_wait *wait = container_of(cb, typeof(*wait), cb);
+
+	wake_up_process(wait->tsk);
+}
+
 /**
  * i915_request_wait - wait until execution of request has finished
  * @rq: the request to wait upon
@@ -1108,8 +1106,7 @@ long i915_request_wait(struct i915_request *rq,
 {
 	const int state = flags & I915_WAIT_INTERRUPTIBLE ?
 		TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE;
-	DEFINE_WAIT_FUNC(exec, default_wake_function);
-	struct intel_wait wait;
+	struct request_wait wait;
 
 	might_sleep();
 	GEM_BUG_ON(timeout < 0);
@@ -1121,47 +1118,24 @@ long i915_request_wait(struct i915_request *rq,
 		return -ETIME;
 
 	trace_i915_request_wait_begin(rq, flags);
-	add_wait_queue(&rq->execute, &exec);
-	intel_wait_init(&wait);
-	if (flags & I915_WAIT_PRIORITY)
-		i915_schedule_bump_priority(rq, I915_PRIORITY_WAIT);
-
-restart:
-	do {
-		set_current_state(state);
-		if (intel_wait_update_request(&wait, rq))
-			break;
-
-		if (signal_pending_state(state, current)) {
-			timeout = -ERESTARTSYS;
-			goto complete;
-		}
 
-		if (!timeout) {
-			timeout = -ETIME;
-			goto complete;
-		}
+	/* Optimistic short spin before touching IRQs */
+	if (__i915_spin_request(rq, state, 5))
+		goto out;
 
-		timeout = io_schedule_timeout(timeout);
-	} while (1);
+	if (flags & I915_WAIT_PRIORITY)
+		i915_schedule_bump_priority(rq, I915_PRIORITY_WAIT);
 
-	GEM_BUG_ON(!intel_wait_has_seqno(&wait));
-	GEM_BUG_ON(!i915_sw_fence_signaled(&rq->submit));
+	wait.tsk = current;
+	if (dma_fence_add_callback(&rq->fence, &wait.cb, request_wait_wake))
+		goto out;
 
-	/* Optimistic short spin before touching IRQs */
-	if (__i915_spin_request(rq, wait.seqno, state, 5))
-		goto complete;
+	for (;;) {
+		set_current_state(state);
 
-	set_current_state(state);
-	if (intel_engine_add_wait(rq->engine, &wait))
-		/*
-		 * In order to check that we haven't missed the interrupt
-		 * as we enabled it, we need to kick ourselves to do a
-		 * coherent check on the seqno before we sleep.
-		 */
-		goto wakeup;
+		if (i915_request_completed(rq))
+			break;
 
-	for (;;) {
 		if (signal_pending_state(state, current)) {
 			timeout = -ERESTARTSYS;
 			break;
@@ -1173,33 +1147,13 @@ long i915_request_wait(struct i915_request *rq,
 		}
 
 		timeout = io_schedule_timeout(timeout);
-
-		if (intel_wait_complete(&wait) &&
-		    intel_wait_check_request(&wait, rq))
-			break;
-
-		set_current_state(state);
-
-wakeup:
-		if (i915_request_completed(rq))
-			break;
-
-		/* Only spin if we know the GPU is processing this request */
-		if (__i915_spin_request(rq, wait.seqno, state, 2))
-			break;
-
-		if (!intel_wait_check_request(&wait, rq)) {
-			intel_engine_remove_wait(rq->engine, &wait);
-			goto restart;
-		}
 	}
-
-	intel_engine_remove_wait(rq->engine, &wait);
-complete:
 	__set_current_state(TASK_RUNNING);
-	remove_wait_queue(&rq->execute, &exec);
-	trace_i915_request_wait_end(rq);
 
+	dma_fence_remove_callback(&rq->fence, &wait.cb);
+
+out:
+	trace_i915_request_wait_end(rq);
 	return timeout;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h
index 83ce982dcbd9..b6d473923506 100644
--- a/drivers/gpu/drm/i915/i915_request.h
+++ b/drivers/gpu/drm/i915/i915_request.h
@@ -38,23 +38,16 @@ struct drm_i915_gem_object;
 struct i915_request;
 struct i915_timeline;
 
-struct intel_wait {
-	struct rb_node node;
-	struct task_struct *tsk;
-	struct i915_request *request;
-	u32 seqno;
-};
-
-struct intel_signal_node {
-	struct intel_wait wait;
-	struct list_head link;
-};
-
 struct i915_capture_list {
 	struct i915_capture_list *next;
 	struct i915_vma *vma;
 };
 
+enum {
+	I915_FENCE_FLAG_ACTIVE = DMA_FENCE_FLAG_USER_BITS,
+	I915_FENCE_FLAG_SIGNAL,
+};
+
 /**
  * Request queue structure.
  *
@@ -97,7 +90,7 @@ struct i915_request {
 	struct intel_context *hw_context;
 	struct intel_ring *ring;
 	struct i915_timeline *timeline;
-	struct intel_signal_node signaling;
+	struct list_head signal_link;
 
 	/*
 	 * The rcu epoch of when this request was allocated. Used to judiciously
@@ -116,7 +109,6 @@ struct i915_request {
 	 */
 	struct i915_sw_fence submit;
 	wait_queue_entry_t submitq;
-	wait_queue_head_t execute;
 
 	/*
 	 * A list of everyone we wait upon, and everyone who waits upon us.
@@ -255,7 +247,7 @@ i915_request_put(struct i915_request *rq)
  * that it has passed the global seqno and the global seqno is unchanged
  * after the read, it is indeed complete).
  */
-static u32
+static inline u32
 i915_request_global_seqno(const struct i915_request *request)
 {
 	return READ_ONCE(request->global_seqno);
diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
index eff76558b958..d846f49401a6 100644
--- a/drivers/gpu/drm/i915/i915_reset.c
+++ b/drivers/gpu/drm/i915/i915_reset.c
@@ -747,18 +747,19 @@ static void reset_restart(struct drm_i915_private *i915)
 
 static void nop_submit_request(struct i915_request *request)
 {
+	struct intel_engine_cs *engine = request->engine;
 	unsigned long flags;
 
 	GEM_TRACE("%s fence %llx:%lld -> -EIO\n",
-		  request->engine->name,
-		  request->fence.context, request->fence.seqno);
+		  engine->name, request->fence.context, request->fence.seqno);
 	dma_fence_set_error(&request->fence, -EIO);
 
-	spin_lock_irqsave(&request->engine->timeline.lock, flags);
+	spin_lock_irqsave(&engine->timeline.lock, flags);
 	__i915_request_submit(request);
 	i915_request_fake_complete(request);
-	intel_engine_write_global_seqno(request->engine, request->global_seqno);
-	spin_unlock_irqrestore(&request->engine->timeline.lock, flags);
+	spin_unlock_irqrestore(&engine->timeline.lock, flags);
+
+	intel_engine_queue_breadcrumbs(engine);
 }
 
 void i915_gem_set_wedged(struct drm_i915_private *i915)
@@ -813,7 +814,7 @@ void i915_gem_set_wedged(struct drm_i915_private *i915)
 
 	for_each_engine(engine, i915, id) {
 		reset_finish_engine(engine);
-		intel_engine_wakeup(engine);
+		intel_engine_signal_breadcrumbs(engine);
 	}
 
 	smp_mb__before_atomic();
diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c
index 7b517bf83507..f9fd967bb50c 100644
--- a/drivers/gpu/drm/i915/intel_breadcrumbs.c
+++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
@@ -29,48 +29,135 @@
 
 #define task_asleep(tsk) ((tsk)->state & TASK_NORMAL && !(tsk)->on_rq)
 
-static unsigned int __intel_breadcrumbs_wakeup(struct intel_breadcrumbs *b)
+static void irq_enable(struct intel_engine_cs *engine)
+{
+	if (!engine->irq_enable)
+		return;
+
+	/*
+	 * FIXME: Ideally we want this on the API boundary, but for the
+	 * sake of testing with mock breadcrumbs (no HW so unable to
+	 * enable irqs) we place it deep within the bowels, at the point
+	 * of no return.
+	 */
+	GEM_BUG_ON(!intel_irqs_enabled(engine->i915));
+
+	/* Caller disables interrupts */
+	spin_lock(&engine->i915->irq_lock);
+	engine->irq_enable(engine);
+	spin_unlock(&engine->i915->irq_lock);
+}
+
+static void irq_disable(struct intel_engine_cs *engine)
 {
-	struct intel_wait *wait;
-	unsigned int result = 0;
+	if (!engine->irq_disable)
+		return;
+
+	/* Caller disables interrupts */
+	spin_lock(&engine->i915->irq_lock);
+	engine->irq_disable(engine);
+	spin_unlock(&engine->i915->irq_lock);
+}
 
+static void __intel_breadcrumbs_disarm_irq(struct intel_breadcrumbs *b)
+{
 	lockdep_assert_held(&b->irq_lock);
 
-	wait = b->irq_wait;
-	if (wait) {
-		/*
-		 * N.B. Since task_asleep() and ttwu are not atomic, the
-		 * waiter may actually go to sleep after the check, causing
-		 * us to suppress a valid wakeup. We prefer to reduce the
-		 * number of false positive missed_breadcrumb() warnings
-		 * at the expense of a few false negatives, as it it easy
-		 * to trigger a false positive under heavy load. Enough
-		 * signal should remain from genuine missed_breadcrumb()
-		 * for us to detect in CI.
-		 */
-		bool was_asleep = task_asleep(wait->tsk);
-
-		result = ENGINE_WAKEUP_WAITER;
-		if (wake_up_process(wait->tsk) && was_asleep)
-			result |= ENGINE_WAKEUP_ASLEEP;
-	}
+	GEM_BUG_ON(!b->irq_enabled);
+	if (!--b->irq_enabled)
+		irq_disable(container_of(b,
+					 struct intel_engine_cs,
+					 breadcrumbs));
 
-	return result;
+	b->irq_armed = false;
 }
 
-unsigned int intel_engine_wakeup(struct intel_engine_cs *engine)
+void intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine)
 {
 	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	unsigned long flags;
-	unsigned int result;
 
-	spin_lock_irqsave(&b->irq_lock, flags);
-	result = __intel_breadcrumbs_wakeup(b);
-	spin_unlock_irqrestore(&b->irq_lock, flags);
+	if (!b->irq_armed)
+		return;
+
+	spin_lock_irq(&b->irq_lock);
+	if (b->irq_armed)
+		__intel_breadcrumbs_disarm_irq(b);
+	spin_unlock_irq(&b->irq_lock);
+}
+
+bool intel_engine_breadcrumbs_irq(struct intel_engine_cs *engine)
+{
+	struct intel_breadcrumbs *b = &engine->breadcrumbs;
+	struct intel_context *ce, *cn;
+	struct i915_request *rq, *rn;
+	LIST_HEAD(signal);
+
+	spin_lock(&b->irq_lock);
+
+	b->irq_fired = true;
+	if (b->irq_armed && list_empty(&b->signalers))
+		__intel_breadcrumbs_disarm_irq(b);
+
+	list_for_each_entry_safe(ce, cn, &b->signalers, signal_link) {
+		GEM_BUG_ON(list_empty(&ce->signals));
+
+		list_for_each_entry_safe(rq, rn, &ce->signals, signal_link) {
+			if (!i915_request_completed(rq))
+				break;
+
+			GEM_BUG_ON(!test_bit(I915_FENCE_FLAG_SIGNAL,
+					     &rq->fence.flags));
+			clear_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags);
+
+			if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
+				     &rq->fence.flags))
+				continue;
+
+			/*
+			 * Queue for execution after dropping the signaling
+			 * spinlock as the callback chain may end adding
+			 * more signalers to the same context or engine.
+			 */
+			i915_request_get(rq);
+			list_add_tail(&rq->signal_link, &signal);
+		}
+
+		if (!list_is_first(&rq->signal_link, &ce->signals)) {
+			__list_del_many(&ce->signals, &rq->signal_link);
+			if (&ce->signals == &rq->signal_link)
+				list_del_init(&ce->signal_link);
+		}
+	}
+
+	spin_unlock(&b->irq_lock);
+
+	list_for_each_entry_safe(rq, rn, &signal, signal_link) {
+		dma_fence_signal(&rq->fence);
+		i915_request_put(rq);
+	}
+
+	return !list_empty(&signal);
+}
+
+bool intel_engine_signal_breadcrumbs(struct intel_engine_cs *engine)
+{
+	bool result;
+
+	local_irq_disable();
+	result = intel_engine_breadcrumbs_irq(engine);
+	local_irq_enable();
 
 	return result;
 }
 
+static void signal_irq_work(struct irq_work *work)
+{
+	struct intel_engine_cs *engine =
+		container_of(work, typeof(*engine), breadcrumbs.irq_work);
+
+	intel_engine_breadcrumbs_irq(engine);
+}
+
 static unsigned long wait_timeout(void)
 {
 	return round_jiffies_up(jiffies + DRM_I915_HANGCHECK_JIFFIES);
@@ -94,19 +181,15 @@ static void intel_breadcrumbs_hangcheck(struct timer_list *t)
 	struct intel_engine_cs *engine =
 		from_timer(engine, t, breadcrumbs.hangcheck);
 	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	unsigned int irq_count;
 
 	if (!b->irq_armed)
 		return;
 
-	irq_count = READ_ONCE(b->irq_count);
-	if (b->hangcheck_interrupts != irq_count) {
-		b->hangcheck_interrupts = irq_count;
-		mod_timer(&b->hangcheck, wait_timeout());
-		return;
-	}
+	if (b->irq_fired)
+		goto rearm;
 
-	/* We keep the hangcheck timer alive until we disarm the irq, even
+	/*
+	 * We keep the hangcheck timer alive until we disarm the irq, even
 	 * if there are no waiters at present.
 	 *
 	 * If the waiter was currently running, assume it hasn't had a chance
@@ -118,10 +201,13 @@ static void intel_breadcrumbs_hangcheck(struct timer_list *t)
 	 * but we still have a waiter. Assuming all batches complete within
 	 * DRM_I915_HANGCHECK_JIFFIES [1.5s]!
 	 */
-	if (intel_engine_wakeup(engine) & ENGINE_WAKEUP_ASLEEP) {
+	synchronize_hardirq(engine->i915->drm.irq);
+	if (intel_engine_signal_breadcrumbs(engine)) {
 		missed_breadcrumb(engine);
 		mod_timer(&b->fake_irq, jiffies + 1);
 	} else {
+rearm:
+		b->irq_fired = false;
 		mod_timer(&b->hangcheck, wait_timeout());
 	}
 }
@@ -140,11 +226,7 @@ static void intel_breadcrumbs_fake_irq(struct timer_list *t)
 	 * oldest waiter to do the coherent seqno check.
 	 */
 
-	spin_lock_irq(&b->irq_lock);
-	if (b->irq_armed && !__intel_breadcrumbs_wakeup(b))
-		__intel_engine_disarm_breadcrumbs(engine);
-	spin_unlock_irq(&b->irq_lock);
-	if (!b->irq_armed)
+	if (!intel_engine_signal_breadcrumbs(engine) && !b->irq_armed)
 		return;
 
 	/* If the user has disabled the fake-irq, restore the hangchecking */
@@ -156,51 +238,6 @@ static void intel_breadcrumbs_fake_irq(struct timer_list *t)
 	mod_timer(&b->fake_irq, jiffies + 1);
 }
 
-static void irq_enable(struct intel_engine_cs *engine)
-{
-	if (!engine->irq_enable)
-		return;
-
-	/*
-	 * FIXME: Ideally we want this on the API boundary, but for the
-	 * sake of testing with mock breadcrumbs (no HW so unable to
-	 * enable irqs) we place it deep within the bowels, at the point
-	 * of no return.
-	 */
-	GEM_BUG_ON(!intel_irqs_enabled(engine->i915));
-
-	/* Caller disables interrupts */
-	spin_lock(&engine->i915->irq_lock);
-	engine->irq_enable(engine);
-	spin_unlock(&engine->i915->irq_lock);
-}
-
-static void irq_disable(struct intel_engine_cs *engine)
-{
-	if (!engine->irq_disable)
-		return;
-
-	/* Caller disables interrupts */
-	spin_lock(&engine->i915->irq_lock);
-	engine->irq_disable(engine);
-	spin_unlock(&engine->i915->irq_lock);
-}
-
-void __intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-
-	lockdep_assert_held(&b->irq_lock);
-	GEM_BUG_ON(b->irq_wait);
-	GEM_BUG_ON(!b->irq_armed);
-
-	GEM_BUG_ON(!b->irq_enabled);
-	if (!--b->irq_enabled)
-		irq_disable(engine);
-
-	b->irq_armed = false;
-}
-
 void intel_engine_pin_breadcrumbs_irq(struct intel_engine_cs *engine)
 {
 	struct intel_breadcrumbs *b = &engine->breadcrumbs;
@@ -223,40 +260,6 @@ void intel_engine_unpin_breadcrumbs_irq(struct intel_engine_cs *engine)
 	spin_unlock_irq(&b->irq_lock);
 }
 
-void intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	struct intel_wait *wait, *n;
-
-	if (!b->irq_armed)
-		return;
-
-	/*
-	 * We only disarm the irq when we are idle (all requests completed),
-	 * so if the bottom-half remains asleep, it missed the request
-	 * completion.
-	 */
-	if (intel_engine_wakeup(engine) & ENGINE_WAKEUP_ASLEEP)
-		missed_breadcrumb(engine);
-
-	spin_lock_irq(&b->rb_lock);
-
-	spin_lock(&b->irq_lock);
-	b->irq_wait = NULL;
-	if (b->irq_armed)
-		__intel_engine_disarm_breadcrumbs(engine);
-	spin_unlock(&b->irq_lock);
-
-	rbtree_postorder_for_each_entry_safe(wait, n, &b->waiters, node) {
-		GEM_BUG_ON(!intel_engine_signaled(engine, wait->seqno));
-		RB_CLEAR_NODE(&wait->node);
-		wake_up_process(wait->tsk);
-	}
-	b->waiters = RB_ROOT;
-
-	spin_unlock_irq(&b->rb_lock);
-}
-
 static bool use_fake_irq(const struct intel_breadcrumbs *b)
 {
 	const struct intel_engine_cs *engine =
@@ -272,7 +275,7 @@ static bool use_fake_irq(const struct intel_breadcrumbs *b)
 	 * engine->seqno_barrier(), a timing error that should be transient
 	 * and unlikely to reoccur.
 	 */
-	return READ_ONCE(b->irq_count) == b->hangcheck_interrupts;
+	return !b->irq_fired;
 }
 
 static void enable_fake_irq(struct intel_breadcrumbs *b)
@@ -284,7 +287,7 @@ static void enable_fake_irq(struct intel_breadcrumbs *b)
 		mod_timer(&b->hangcheck, wait_timeout());
 }
 
-static bool __intel_breadcrumbs_enable_irq(struct intel_breadcrumbs *b)
+static bool __intel_breadcrumbs_arm_irq(struct intel_breadcrumbs *b)
 {
 	struct intel_engine_cs *engine =
 		container_of(b, struct intel_engine_cs, breadcrumbs);
@@ -323,537 +326,135 @@ static bool __intel_breadcrumbs_enable_irq(struct intel_breadcrumbs *b)
 	return enabled;
 }
 
-static inline struct intel_wait *to_wait(struct rb_node *node)
+void intel_engine_init_breadcrumbs(struct intel_engine_cs *engine)
 {
-	return rb_entry(node, struct intel_wait, node);
-}
+	struct intel_breadcrumbs *b = &engine->breadcrumbs;
 
-static inline void __intel_breadcrumbs_finish(struct intel_breadcrumbs *b,
-					      struct intel_wait *wait)
-{
-	lockdep_assert_held(&b->rb_lock);
-	GEM_BUG_ON(b->irq_wait == wait);
+	spin_lock_init(&b->irq_lock);
+	INIT_LIST_HEAD(&b->signalers);
 
-	/*
-	 * This request is completed, so remove it from the tree, mark it as
-	 * complete, and *then* wake up the associated task. N.B. when the
-	 * task wakes up, it will find the empty rb_node, discern that it
-	 * has already been removed from the tree and skip the serialisation
-	 * of the b->rb_lock and b->irq_lock. This means that the destruction
-	 * of the intel_wait is not serialised with the interrupt handler
-	 * by the waiter - it must instead be serialised by the caller.
-	 */
-	rb_erase(&wait->node, &b->waiters);
-	RB_CLEAR_NODE(&wait->node);
+	init_irq_work(&b->irq_work, signal_irq_work);
 
-	if (wait->tsk->state != TASK_RUNNING)
-		wake_up_process(wait->tsk); /* implicit smp_wmb() */
+	timer_setup(&b->fake_irq, intel_breadcrumbs_fake_irq, 0);
+	timer_setup(&b->hangcheck, intel_breadcrumbs_hangcheck, 0);
 }
 
-static inline void __intel_breadcrumbs_next(struct intel_engine_cs *engine,
-					    struct rb_node *next)
+static void cancel_fake_irq(struct intel_engine_cs *engine)
 {
 	struct intel_breadcrumbs *b = &engine->breadcrumbs;
 
-	spin_lock(&b->irq_lock);
-	GEM_BUG_ON(!b->irq_armed);
-	GEM_BUG_ON(!b->irq_wait);
-	b->irq_wait = to_wait(next);
-	spin_unlock(&b->irq_lock);
-
-	/* We always wake up the next waiter that takes over as the bottom-half
-	 * as we may delegate not only the irq-seqno barrier to the next waiter
-	 * but also the task of waking up concurrent waiters.
-	 */
-	if (next)
-		wake_up_process(to_wait(next)->tsk);
+	del_timer_sync(&b->fake_irq); /* may queue b->hangcheck */
+	del_timer_sync(&b->hangcheck);
+	clear_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings);
 }
 
-static bool __intel_engine_add_wait(struct intel_engine_cs *engine,
-				    struct intel_wait *wait)
+void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine)
 {
 	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	struct rb_node **p, *parent, *completed;
-	bool first, armed;
-	u32 seqno;
+	unsigned long flags;
 
-	GEM_BUG_ON(!wait->seqno);
+	spin_lock_irqsave(&b->irq_lock, flags);
 
-	/* Insert the request into the retirement ordered list
-	 * of waiters by walking the rbtree. If we are the oldest
-	 * seqno in the tree (the first to be retired), then
-	 * set ourselves as the bottom-half.
-	 *
-	 * As we descend the tree, prune completed branches since we hold the
-	 * spinlock we know that the first_waiter must be delayed and can
-	 * reduce some of the sequential wake up latency if we take action
-	 * ourselves and wake up the completed tasks in parallel. Also, by
-	 * removing stale elements in the tree, we may be able to reduce the
-	 * ping-pong between the old bottom-half and ourselves as first-waiter.
+	/*
+	 * Leave the fake_irq timer enabled (if it is running), but clear the
+	 * bit so that it turns itself off on its next wake up and goes back
+	 * to the long hangcheck interval if still required.
 	 */
-	armed = false;
-	first = true;
-	parent = NULL;
-	completed = NULL;
-	seqno = intel_engine_get_seqno(engine);
-
-	 /* If the request completed before we managed to grab the spinlock,
-	  * return now before adding ourselves to the rbtree. We let the
-	  * current bottom-half handle any pending wakeups and instead
-	  * try and get out of the way quickly.
-	  */
-	if (i915_seqno_passed(seqno, wait->seqno)) {
-		RB_CLEAR_NODE(&wait->node);
-		return first;
-	}
-
-	p = &b->waiters.rb_node;
-	while (*p) {
-		parent = *p;
-		if (wait->seqno == to_wait(parent)->seqno) {
-			/* We have multiple waiters on the same seqno, select
-			 * the highest priority task (that with the smallest
-			 * task->prio) to serve as the bottom-half for this
-			 * group.
-			 */
-			if (wait->tsk->prio > to_wait(parent)->tsk->prio) {
-				p = &parent->rb_right;
-				first = false;
-			} else {
-				p = &parent->rb_left;
-			}
-		} else if (i915_seqno_passed(wait->seqno,
-					     to_wait(parent)->seqno)) {
-			p = &parent->rb_right;
-			if (i915_seqno_passed(seqno, to_wait(parent)->seqno))
-				completed = parent;
-			else
-				first = false;
-		} else {
-			p = &parent->rb_left;
-		}
-	}
-	rb_link_node(&wait->node, parent, p);
-	rb_insert_color(&wait->node, &b->waiters);
-
-	if (first) {
-		spin_lock(&b->irq_lock);
-		b->irq_wait = wait;
-		/* After assigning ourselves as the new bottom-half, we must
-		 * perform a cursory check to prevent a missed interrupt.
-		 * Either we miss the interrupt whilst programming the hardware,
-		 * or if there was a previous waiter (for a later seqno) they
-		 * may be woken instead of us (due to the inherent race
-		 * in the unlocked read of b->irq_seqno_bh in the irq handler)
-		 * and so we miss the wake up.
-		 */
-		armed = __intel_breadcrumbs_enable_irq(b);
-		spin_unlock(&b->irq_lock);
-	}
-
-	if (completed) {
-		/* Advance the bottom-half (b->irq_wait) before we wake up
-		 * the waiters who may scribble over their intel_wait
-		 * just as the interrupt handler is dereferencing it via
-		 * b->irq_wait.
-		 */
-		if (!first) {
-			struct rb_node *next = rb_next(completed);
-			GEM_BUG_ON(next == &wait->node);
-			__intel_breadcrumbs_next(engine, next);
-		}
-
-		do {
-			struct intel_wait *crumb = to_wait(completed);
-			completed = rb_prev(completed);
-			__intel_breadcrumbs_finish(b, crumb);
-		} while (completed);
-	}
-
-	GEM_BUG_ON(!b->irq_wait);
-	GEM_BUG_ON(!b->irq_armed);
-	GEM_BUG_ON(rb_first(&b->waiters) != &b->irq_wait->node);
-
-	return armed;
-}
-
-bool intel_engine_add_wait(struct intel_engine_cs *engine,
-			   struct intel_wait *wait)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	bool armed;
-
-	spin_lock_irq(&b->rb_lock);
-	armed = __intel_engine_add_wait(engine, wait);
-	spin_unlock_irq(&b->rb_lock);
-	if (armed)
-		return armed;
-
-	/* Make the caller recheck if its request has already started. */
-	return intel_engine_has_started(engine, wait->seqno);
-}
-
-static inline bool chain_wakeup(struct rb_node *rb, int priority)
-{
-	return rb && to_wait(rb)->tsk->prio <= priority;
-}
+	clear_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings);
 
-static inline int wakeup_priority(struct intel_breadcrumbs *b,
-				  struct task_struct *tsk)
-{
-	if (tsk == b->signaler)
-		return INT_MIN;
+	if (b->irq_enabled)
+		irq_enable(engine);
 	else
-		return tsk->prio;
-}
-
-static void __intel_engine_remove_wait(struct intel_engine_cs *engine,
-				       struct intel_wait *wait)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-
-	lockdep_assert_held(&b->rb_lock);
-
-	if (RB_EMPTY_NODE(&wait->node))
-		goto out;
-
-	if (b->irq_wait == wait) {
-		const int priority = wakeup_priority(b, wait->tsk);
-		struct rb_node *next;
-
-		/* We are the current bottom-half. Find the next candidate,
-		 * the first waiter in the queue on the remaining oldest
-		 * request. As multiple seqnos may complete in the time it
-		 * takes us to wake up and find the next waiter, we have to
-		 * wake up that waiter for it to perform its own coherent
-		 * completion check.
-		 */
-		next = rb_next(&wait->node);
-		if (chain_wakeup(next, priority)) {
-			/* If the next waiter is already complete,
-			 * wake it up and continue onto the next waiter. So
-			 * if have a small herd, they will wake up in parallel
-			 * rather than sequentially, which should reduce
-			 * the overall latency in waking all the completed
-			 * clients.
-			 *
-			 * However, waking up a chain adds extra latency to
-			 * the first_waiter. This is undesirable if that
-			 * waiter is a high priority task.
-			 */
-			u32 seqno = intel_engine_get_seqno(engine);
-
-			while (i915_seqno_passed(seqno, to_wait(next)->seqno)) {
-				struct rb_node *n = rb_next(next);
-
-				__intel_breadcrumbs_finish(b, to_wait(next));
-				next = n;
-				if (!chain_wakeup(next, priority))
-					break;
-			}
-		}
-
-		__intel_breadcrumbs_next(engine, next);
-	} else {
-		GEM_BUG_ON(rb_first(&b->waiters) == &wait->node);
-	}
-
-	GEM_BUG_ON(RB_EMPTY_NODE(&wait->node));
-	rb_erase(&wait->node, &b->waiters);
-	RB_CLEAR_NODE(&wait->node);
-
-out:
-	GEM_BUG_ON(b->irq_wait == wait);
-	GEM_BUG_ON(rb_first(&b->waiters) !=
-		   (b->irq_wait ? &b->irq_wait->node : NULL));
-}
-
-void intel_engine_remove_wait(struct intel_engine_cs *engine,
-			      struct intel_wait *wait)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-
-	/* Quick check to see if this waiter was already decoupled from
-	 * the tree by the bottom-half to avoid contention on the spinlock
-	 * by the herd.
-	 */
-	if (RB_EMPTY_NODE(&wait->node)) {
-		GEM_BUG_ON(READ_ONCE(b->irq_wait) == wait);
-		return;
-	}
+		irq_disable(engine);
 
-	spin_lock_irq(&b->rb_lock);
-	__intel_engine_remove_wait(engine, wait);
-	spin_unlock_irq(&b->rb_lock);
+	spin_unlock_irqrestore(&b->irq_lock, flags);
 }
 
-static void signaler_set_rtpriority(void)
+void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine)
 {
-	 struct sched_param param = { .sched_priority = 1 };
-
-	 sched_setscheduler_nocheck(current, SCHED_FIFO, &param);
+	cancel_fake_irq(engine);
 }
 
-static int intel_breadcrumbs_signaler(void *arg)
+bool intel_engine_enable_signaling(struct i915_request *rq)
 {
-	struct intel_engine_cs *engine = arg;
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	struct i915_request *rq, *n;
-
-	/* Install ourselves with high priority to reduce signalling latency */
-	signaler_set_rtpriority();
-
-	do {
-		bool do_schedule = true;
-		LIST_HEAD(list);
-		u32 seqno;
-
-		set_current_state(TASK_INTERRUPTIBLE);
-		if (list_empty(&b->signals))
-			goto sleep;
-
-		/*
-		 * We are either woken up by the interrupt bottom-half,
-		 * or by a client adding a new signaller. In both cases,
-		 * the GPU seqno may have advanced beyond our oldest signal.
-		 * If it has, propagate the signal, remove the waiter and
-		 * check again with the next oldest signal. Otherwise we
-		 * need to wait for a new interrupt from the GPU or for
-		 * a new client.
-		 */
-		seqno = intel_engine_get_seqno(engine);
-
-		spin_lock_irq(&b->rb_lock);
-		list_for_each_entry_safe(rq, n, &b->signals, signaling.link) {
-			u32 this = rq->signaling.wait.seqno;
-
-			GEM_BUG_ON(!rq->signaling.wait.seqno);
-
-			if (!i915_seqno_passed(seqno, this))
-				break;
+	struct intel_breadcrumbs *b = &rq->engine->breadcrumbs;
 
-			if (likely(this == i915_request_global_seqno(rq))) {
-				__intel_engine_remove_wait(engine,
-							   &rq->signaling.wait);
+	GEM_BUG_ON(test_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags));
 
-				rq->signaling.wait.seqno = 0;
-				__list_del_entry(&rq->signaling.link);
-
-				if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
-					      &rq->fence.flags)) {
-					list_add_tail(&rq->signaling.link,
-						      &list);
-					i915_request_get(rq);
-				}
-			}
-		}
-		spin_unlock_irq(&b->rb_lock);
+	if (!test_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags))
+		return true;
 
-		if (!list_empty(&list)) {
-			local_bh_disable();
-			list_for_each_entry_safe(rq, n, &list, signaling.link) {
-				dma_fence_signal(&rq->fence);
-				GEM_BUG_ON(!i915_request_completed(rq));
-				i915_request_put(rq);
-			}
-			local_bh_enable(); /* kick start the tasklets */
+	spin_lock(&b->irq_lock);
+	if (test_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags) &&
+	    !i915_request_completed(rq)) {
+		struct intel_context *ce = rq->hw_context;
+		struct list_head *pos;
 
-			/*
-			 * If the engine is saturated we may be continually
-			 * processing completed requests. This angers the
-			 * NMI watchdog if we never let anything else
-			 * have access to the CPU. Let's pretend to be nice
-			 * and relinquish the CPU if we burn through the
-			 * entire RT timeslice!
-			 */
-			do_schedule = need_resched();
-		}
+		__intel_breadcrumbs_arm_irq(b);
 
-		if (unlikely(do_schedule)) {
-sleep:
-			if (kthread_should_park())
-				kthread_parkme();
+		list_for_each_prev(pos, &ce->signals) {
+			struct i915_request *it =
+				list_entry(pos, typeof(*it), signal_link);
 
-			if (unlikely(kthread_should_stop()))
+			if (i915_seqno_passed(rq->fence.seqno, it->fence.seqno))
 				break;
-
-			schedule();
 		}
-	} while (1);
-	__set_current_state(TASK_RUNNING);
-
-	return 0;
-}
+		list_add(&rq->signal_link, pos);
+		if (pos == &ce->signals)
+			list_move_tail(&ce->signal_link, &b->signalers);
 
-static void insert_signal(struct intel_breadcrumbs *b,
-			  struct i915_request *request,
-			  const u32 seqno)
-{
-	struct i915_request *iter;
-
-	lockdep_assert_held(&b->rb_lock);
-
-	/*
-	 * A reasonable assumption is that we are called to add signals
-	 * in sequence, as the requests are submitted for execution and
-	 * assigned a global_seqno. This will be the case for the majority
-	 * of internally generated signals (inter-engine signaling).
-	 *
-	 * Out of order waiters triggering random signaling enabling will
-	 * be more problematic, but hopefully rare enough and the list
-	 * small enough that the O(N) insertion sort is not an issue.
-	 */
-
-	list_for_each_entry_reverse(iter, &b->signals, signaling.link)
-		if (i915_seqno_passed(seqno, iter->signaling.wait.seqno))
-			break;
-
-	list_add(&request->signaling.link, &iter->signaling.link);
-}
-
-bool intel_engine_enable_signaling(struct i915_request *request, bool wakeup)
-{
-	struct intel_engine_cs *engine = request->engine;
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	struct intel_wait *wait = &request->signaling.wait;
-	u32 seqno;
-
-	/*
-	 * Note that we may be called from an interrupt handler on another
-	 * device (e.g. nouveau signaling a fence completion causing us
-	 * to submit a request, and so enable signaling). As such,
-	 * we need to make sure that all other users of b->rb_lock protect
-	 * against interrupts, i.e. use spin_lock_irqsave.
-	 */
-
-	/* locked by dma_fence_enable_sw_signaling() (irqsafe fence->lock) */
-	GEM_BUG_ON(!irqs_disabled());
-	lockdep_assert_held(&request->lock);
-
-	seqno = i915_request_global_seqno(request);
-	if (!seqno) /* will be enabled later upon execution */
-		return true;
-
-	GEM_BUG_ON(wait->seqno);
-	wait->tsk = b->signaler;
-	wait->request = request;
-	wait->seqno = seqno;
-
-	/*
-	 * Add ourselves into the list of waiters, but registering our
-	 * bottom-half as the signaller thread. As per usual, only the oldest
-	 * waiter (not just signaller) is tasked as the bottom-half waking
-	 * up all completed waiters after the user interrupt.
-	 *
-	 * If we are the oldest waiter, enable the irq (after which we
-	 * must double check that the seqno did not complete).
-	 */
-	spin_lock(&b->rb_lock);
-	insert_signal(b, request, seqno);
-	wakeup &= __intel_engine_add_wait(engine, wait);
-	spin_unlock(&b->rb_lock);
-
-	if (wakeup) {
-		wake_up_process(b->signaler);
-		return !intel_wait_complete(wait);
+		set_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags);
 	}
+	spin_unlock(&b->irq_lock);
 
-	return true;
+	return !i915_request_completed(rq);
 }
 
-void intel_engine_cancel_signaling(struct i915_request *request)
+void intel_engine_cancel_signaling(struct i915_request *rq)
 {
-	struct intel_engine_cs *engine = request->engine;
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-
-	GEM_BUG_ON(!irqs_disabled());
-	lockdep_assert_held(&request->lock);
+	struct intel_breadcrumbs *b = &rq->engine->breadcrumbs;
 
-	if (!READ_ONCE(request->signaling.wait.seqno))
+	if (!test_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags))
 		return;
 
-	spin_lock(&b->rb_lock);
-	__intel_engine_remove_wait(engine, &request->signaling.wait);
-	if (fetch_and_zero(&request->signaling.wait.seqno))
-		__list_del_entry(&request->signaling.link);
-	spin_unlock(&b->rb_lock);
-}
-
-int intel_engine_init_breadcrumbs(struct intel_engine_cs *engine)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	struct task_struct *tsk;
-
-	spin_lock_init(&b->rb_lock);
-	spin_lock_init(&b->irq_lock);
-
-	timer_setup(&b->fake_irq, intel_breadcrumbs_fake_irq, 0);
-	timer_setup(&b->hangcheck, intel_breadcrumbs_hangcheck, 0);
-
-	INIT_LIST_HEAD(&b->signals);
-
-	/* Spawn a thread to provide a common bottom-half for all signals.
-	 * As this is an asynchronous interface we cannot steal the current
-	 * task for handling the bottom-half to the user interrupt, therefore
-	 * we create a thread to do the coherent seqno dance after the
-	 * interrupt and then signal the waitqueue (via the dma-buf/fence).
-	 */
-	tsk = kthread_run(intel_breadcrumbs_signaler, engine,
-			  "i915/signal:%d", engine->id);
-	if (IS_ERR(tsk))
-		return PTR_ERR(tsk);
-
-	b->signaler = tsk;
-
-	return 0;
-}
+	spin_lock(&b->irq_lock);
+	if (test_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags)) {
+		struct intel_context *ce = rq->hw_context;
 
-static void cancel_fake_irq(struct intel_engine_cs *engine)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
+		list_del(&rq->signal_link);
+		if (list_empty(&ce->signals))
+			list_del_init(&ce->signal_link);
 
-	del_timer_sync(&b->fake_irq); /* may queue b->hangcheck */
-	del_timer_sync(&b->hangcheck);
-	clear_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings);
+		clear_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags);
+	}
+	spin_unlock(&b->irq_lock);
 }
 
-void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine)
+void intel_engine_print_breadcrumbs(struct intel_engine_cs *engine,
+				    struct drm_printer *p)
 {
 	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	unsigned long flags;
+	struct intel_context *ce;
+	struct i915_request *rq;
 
-	spin_lock_irqsave(&b->irq_lock, flags);
-
-	/*
-	 * Leave the fake_irq timer enabled (if it is running), but clear the
-	 * bit so that it turns itself off on its next wake up and goes back
-	 * to the long hangcheck interval if still required.
-	 */
-	clear_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings);
-
-	if (b->irq_enabled)
-		irq_enable(engine);
-	else
-		irq_disable(engine);
-
-	spin_unlock_irqrestore(&b->irq_lock, flags);
-}
-
-void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
+	if (list_empty(&b->signalers))
+		return;
 
-	/* The engines should be idle and all requests accounted for! */
-	WARN_ON(READ_ONCE(b->irq_wait));
-	WARN_ON(!RB_EMPTY_ROOT(&b->waiters));
-	WARN_ON(!list_empty(&b->signals));
+	drm_printf(p, "Signals:\n");
 
-	if (!IS_ERR_OR_NULL(b->signaler))
-		kthread_stop(b->signaler);
+	spin_lock_irq(&b->irq_lock);
+	list_for_each_entry(ce, &b->signalers, signal_link) {
+		list_for_each_entry(rq, &ce->signals, signal_link) {
+			drm_printf(p, "\t[%llx:%llx%s] @ %dms\n",
+				   rq->fence.context, rq->fence.seqno,
+				   i915_request_completed(rq) ? "!" :
+				   i915_request_started(rq) ? "*" :
+				   "",
+				   jiffies_to_msecs(jiffies - rq->emitted_jiffies));
+		}
+	}
+	spin_unlock_irq(&b->irq_lock);
 
-	cancel_fake_irq(engine);
+	if (test_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings))
+		drm_printf(p, "Fake irq active\n");
 }
-
-#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
-#include "selftests/intel_breadcrumbs.c"
-#endif
diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index ae455b874c9f..429f21e16428 100644
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -458,12 +458,6 @@ int intel_engines_init(struct drm_i915_private *dev_priv)
 void intel_engine_write_global_seqno(struct intel_engine_cs *engine, u32 seqno)
 {
 	intel_write_status_page(engine, I915_GEM_HWS_INDEX, seqno);
-
-	/* After manually advancing the seqno, fake the interrupt in case
-	 * there are any waiters for that seqno.
-	 */
-	intel_engine_wakeup(engine);
-
 	GEM_BUG_ON(intel_engine_get_seqno(engine) != seqno);
 }
 
@@ -667,16 +661,10 @@ int intel_engine_init_common(struct intel_engine_cs *engine)
 		}
 	}
 
-	ret = intel_engine_init_breadcrumbs(engine);
-	if (ret)
-		goto err_unpin_preempt;
+	intel_engine_init_breadcrumbs(engine);
 
 	return 0;
 
-err_unpin_preempt:
-	if (i915->preempt_context)
-		__intel_context_unpin(i915->preempt_context, engine);
-
 err_unpin_kernel:
 	__intel_context_unpin(i915->kernel_context, engine);
 	return ret;
@@ -1236,12 +1224,14 @@ static void print_request(struct drm_printer *m,
 
 	x = print_sched_attr(rq->i915, &rq->sched.attr, buf, x, sizeof(buf));
 
-	drm_printf(m, "%s%x%s [%llx:%llx]%s @ %dms: %s\n",
+	drm_printf(m, "%s%x%s%s [%llx:%llx]%s @ %dms: %s\n",
 		   prefix,
 		   rq->global_seqno,
 		   i915_request_completed(rq) ? "!" :
 		   i915_request_started(rq) ? "*" :
 		   "",
+		   test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT,
+			    &rq->fence.flags) ?  "+" : "",
 		   rq->fence.context, rq->fence.seqno,
 		   buf,
 		   jiffies_to_msecs(jiffies - rq->emitted_jiffies),
@@ -1433,12 +1423,9 @@ void intel_engine_dump(struct intel_engine_cs *engine,
 		       struct drm_printer *m,
 		       const char *header, ...)
 {
-	struct intel_breadcrumbs * const b = &engine->breadcrumbs;
 	struct i915_gpu_error * const error = &engine->i915->gpu_error;
 	struct i915_request *rq;
 	intel_wakeref_t wakeref;
-	unsigned long flags;
-	struct rb_node *rb;
 
 	if (header) {
 		va_list ap;
@@ -1504,21 +1491,12 @@ void intel_engine_dump(struct intel_engine_cs *engine,
 
 	intel_execlists_show_requests(engine, m, print_request, 8);
 
-	spin_lock_irqsave(&b->rb_lock, flags);
-	for (rb = rb_first(&b->waiters); rb; rb = rb_next(rb)) {
-		struct intel_wait *w = rb_entry(rb, typeof(*w), node);
-
-		drm_printf(m, "\t%s [%d:%c] waiting for %x\n",
-			   w->tsk->comm, w->tsk->pid,
-			   task_state_to_char(w->tsk),
-			   w->seqno);
-	}
-	spin_unlock_irqrestore(&b->rb_lock, flags);
-
 	drm_printf(m, "HWSP:\n");
 	hexdump(m, engine->status_page.addr, PAGE_SIZE);
 
 	drm_printf(m, "Idle? %s\n", yesno(intel_engine_is_idle(engine)));
+
+	intel_engine_print_breadcrumbs(engine, m);
 }
 
 static u8 user_class_map[] = {
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 2b4beb15a271..97732e387821 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -482,8 +482,8 @@ static void gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
 
 	for (i = 0; i < GEN7_XCS_WA; i++) {
 		*cs++ = MI_STORE_DWORD_INDEX;
-		*cs++ = I915_GEM_HWS_INDEX_ADDR;
-		*cs++ = rq->global_seqno;
+		*cs++ = I915_GEM_HWS_SEQNO_ADDR;
+		*cs++ = rq->fence.seqno;
 	}
 
 	*cs++ = MI_FLUSH_DW;
@@ -733,7 +733,7 @@ static int init_ring_common(struct intel_engine_cs *engine)
 	}
 
 	/* Papering over lost _interrupts_ immediately following the restart */
-	intel_engine_wakeup(engine);
+	intel_engine_queue_breadcrumbs(engine);
 out:
 	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
 
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 5c20b41b6a9b..ca56816902e6 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -5,6 +5,7 @@
 #include <drm/drm_util.h>
 
 #include <linux/hashtable.h>
+#include <linux/irq_work.h>
 #include <linux/seqlock.h>
 
 #include "i915_gem_batch_pool.h"
@@ -380,22 +381,19 @@ struct intel_engine_cs {
 	 * the overhead of waking that client is much preferred.
 	 */
 	struct intel_breadcrumbs {
-		spinlock_t irq_lock; /* protects irq_*; irqsafe */
-		struct intel_wait *irq_wait; /* oldest waiter by retirement */
+		spinlock_t irq_lock;
+		struct list_head signalers;
 
-		spinlock_t rb_lock; /* protects the rb and wraps irq_lock */
-		struct rb_root waiters; /* sorted by retirement, priority */
-		struct list_head signals; /* sorted by retirement */
-		struct task_struct *signaler; /* used for fence signalling */
+		struct irq_work irq_work;
 
 		struct timer_list fake_irq; /* used after a missed interrupt */
 		struct timer_list hangcheck; /* detect missed interrupts */
 
 		unsigned int hangcheck_interrupts;
 		unsigned int irq_enabled;
-		unsigned int irq_count;
 
-		bool irq_armed : 1;
+		bool irq_armed;
+		bool irq_fired;
 	} breadcrumbs;
 
 	struct {
@@ -882,83 +880,32 @@ static inline bool intel_engine_has_started(struct intel_engine_cs *engine,
 void intel_engine_get_instdone(struct intel_engine_cs *engine,
 			       struct intel_instdone *instdone);
 
-/* intel_breadcrumbs.c -- user interrupt bottom-half for waiters */
-int intel_engine_init_breadcrumbs(struct intel_engine_cs *engine);
-
-static inline void intel_wait_init(struct intel_wait *wait)
-{
-	wait->tsk = current;
-	wait->request = NULL;
-}
-
-static inline void intel_wait_init_for_seqno(struct intel_wait *wait, u32 seqno)
-{
-	wait->tsk = current;
-	wait->seqno = seqno;
-}
-
-static inline bool intel_wait_has_seqno(const struct intel_wait *wait)
-{
-	return wait->seqno;
-}
-
-static inline bool
-intel_wait_update_seqno(struct intel_wait *wait, u32 seqno)
-{
-	wait->seqno = seqno;
-	return intel_wait_has_seqno(wait);
-}
-
-static inline bool
-intel_wait_update_request(struct intel_wait *wait,
-			  const struct i915_request *rq)
-{
-	return intel_wait_update_seqno(wait, i915_request_global_seqno(rq));
-}
-
-static inline bool
-intel_wait_check_seqno(const struct intel_wait *wait, u32 seqno)
-{
-	return wait->seqno == seqno;
-}
-
-static inline bool
-intel_wait_check_request(const struct intel_wait *wait,
-			 const struct i915_request *rq)
-{
-	return intel_wait_check_seqno(wait, i915_request_global_seqno(rq));
-}
-
-static inline bool intel_wait_complete(const struct intel_wait *wait)
-{
-	return RB_EMPTY_NODE(&wait->node);
-}
+void intel_engine_init_breadcrumbs(struct intel_engine_cs *engine);
+void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine);
 
-bool intel_engine_add_wait(struct intel_engine_cs *engine,
-			   struct intel_wait *wait);
-void intel_engine_remove_wait(struct intel_engine_cs *engine,
-			      struct intel_wait *wait);
-bool intel_engine_enable_signaling(struct i915_request *request, bool wakeup);
+bool intel_engine_enable_signaling(struct i915_request *request);
 void intel_engine_cancel_signaling(struct i915_request *request);
 
-static inline bool intel_engine_has_waiter(const struct intel_engine_cs *engine)
-{
-	return READ_ONCE(engine->breadcrumbs.irq_wait);
-}
-
-unsigned int intel_engine_wakeup(struct intel_engine_cs *engine);
-#define ENGINE_WAKEUP_WAITER BIT(0)
-#define ENGINE_WAKEUP_ASLEEP BIT(1)
-
 void intel_engine_pin_breadcrumbs_irq(struct intel_engine_cs *engine);
 void intel_engine_unpin_breadcrumbs_irq(struct intel_engine_cs *engine);
 
-void __intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine);
+bool intel_engine_signal_breadcrumbs(struct intel_engine_cs *engine);
 void intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine);
 
+static inline void
+intel_engine_queue_breadcrumbs(struct intel_engine_cs *engine)
+{
+	irq_work_queue(&engine->breadcrumbs.irq_work);
+}
+
+bool intel_engine_breadcrumbs_irq(struct intel_engine_cs *engine);
+
 void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine);
 void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine);
 
+void intel_engine_print_breadcrumbs(struct intel_engine_cs *engine,
+				    struct drm_printer *p);
+
 static inline u32 *gen8_emit_pipe_control(u32 *batch, u32 flags, u32 offset)
 {
 	memset(batch, 0, 6 * sizeof(u32));
diff --git a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
index 4a83a1c6c406..88e5ab586337 100644
--- a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
+++ b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
@@ -15,7 +15,6 @@ selftest(scatterlist, scatterlist_mock_selftests)
 selftest(syncmap, i915_syncmap_mock_selftests)
 selftest(uncore, intel_uncore_mock_selftests)
 selftest(engine, intel_engine_cs_mock_selftests)
-selftest(breadcrumbs, intel_breadcrumbs_mock_selftests)
 selftest(timelines, i915_timeline_mock_selftests)
 selftest(requests, i915_request_mock_selftests)
 selftest(objects, i915_gem_object_mock_selftests)
diff --git a/drivers/gpu/drm/i915/selftests/i915_request.c b/drivers/gpu/drm/i915/selftests/i915_request.c
index 2e14d6d3bad7..48b6159afe64 100644
--- a/drivers/gpu/drm/i915/selftests/i915_request.c
+++ b/drivers/gpu/drm/i915/selftests/i915_request.c
@@ -25,8 +25,11 @@
 #include <linux/prime_numbers.h>
 
 #include "../i915_selftest.h"
+#include "i915_random.h"
+#include "lib_sw_fence.h"
 
 #include "mock_context.h"
+#include "mock_drm.h"
 #include "mock_gem_device.h"
 
 static int igt_add_request(void *arg)
@@ -246,6 +249,239 @@ static int igt_request_rewind(void *arg)
 	return err;
 }
 
+struct smoketest {
+	struct intel_engine_cs *engine;
+	struct i915_gem_context **contexts;
+	unsigned int ncontexts, max_batch;
+	atomic_long_t num_waits, num_fences;
+	struct i915_request *(*request_alloc)(struct i915_gem_context *,
+					      struct intel_engine_cs *);
+
+};
+
+static struct i915_request *
+__mock_request_alloc(struct i915_gem_context *ctx,
+		     struct intel_engine_cs *engine)
+{
+	return mock_request(engine, ctx, 0);
+}
+
+static struct i915_request *
+__live_request_alloc(struct i915_gem_context *ctx,
+		     struct intel_engine_cs *engine)
+{
+	return i915_request_alloc(engine, ctx);
+}
+
+static int __igt_breadcrumbs_smoketest(void *arg)
+{
+	struct smoketest *t = arg;
+	struct mutex *BKL = &t->engine->i915->drm.struct_mutex;
+	struct i915_request **requests;
+	I915_RND_STATE(prng);
+	const unsigned int total = 4 * t->ncontexts + 1;
+	const unsigned int max_batch = min(t->ncontexts, t->max_batch) - 1;
+	unsigned int num_waits = 0, num_fences = 0;
+	unsigned int *order;
+	int err = 0;
+
+	requests = kmalloc_array(total, sizeof(*requests), GFP_KERNEL);
+	if (!requests)
+		return -ENOMEM;
+
+	order = i915_random_order(total, &prng);
+	if (!order) {
+		err = -ENOMEM;
+		goto out_requests;
+	}
+
+	while (!kthread_should_stop()) {
+		struct i915_sw_fence *submit, *wait;
+		unsigned int n, count;
+
+		submit = heap_fence_create(GFP_KERNEL);
+		if (!submit) {
+			err = -ENOMEM;
+			break;
+		}
+
+		wait = heap_fence_create(GFP_KERNEL);
+		if (!wait) {
+			i915_sw_fence_commit(submit);
+			heap_fence_put(submit);
+			err = ENOMEM;
+			break;
+		}
+
+		i915_random_reorder(order, total, &prng);
+		count = 1 + i915_prandom_u32_max_state(max_batch, &prng);
+
+		for (n = 0; n < count; n++) {
+			struct i915_gem_context *ctx =
+				t->contexts[order[n] % t->ncontexts];
+			struct i915_request *rq;
+
+			mutex_lock(BKL);
+
+			rq = t->request_alloc(ctx, t->engine);
+			if (IS_ERR(rq)) {
+				mutex_unlock(BKL);
+				err = PTR_ERR(rq);
+				count = n;
+				break;
+			}
+
+			err = i915_sw_fence_await_sw_fence_gfp(&rq->submit,
+							       submit,
+							       GFP_KERNEL);
+
+			requests[n] = i915_request_get(rq);
+			i915_request_add(rq);
+
+			mutex_unlock(BKL);
+
+			if (err >= 0)
+				err = i915_sw_fence_await_dma_fence(wait,
+								    &rq->fence,
+								    0,
+								    GFP_KERNEL);
+			if (err < 0) {
+				i915_request_put(rq);
+				count = n;
+				break;
+			}
+		}
+
+		i915_sw_fence_commit(submit);
+		i915_sw_fence_commit(wait);
+
+		if (!wait_event_timeout(wait->wait,
+					i915_sw_fence_done(wait),
+					HZ / 2)) {
+			struct i915_request *rq = requests[count - 1];
+
+			pr_err("waiting for %d fences (last %llx:%lld) on %s timed out!\n",
+			       count,
+			       rq->fence.context, rq->fence.seqno,
+			       t->engine->name);
+			i915_gem_set_wedged(t->engine->i915);
+			GEM_BUG_ON(!i915_request_completed(rq));
+			i915_sw_fence_wait(wait);
+			err = -EIO;
+		}
+
+		for (n = 0; n < count; n++) {
+			struct i915_request *rq = requests[n];
+
+			if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
+				      &rq->fence.flags)) {
+				pr_err("%llu:%llu was not signaled!\n",
+				       rq->fence.context, rq->fence.seqno);
+				err = -EINVAL;
+			}
+
+			i915_request_put(rq);
+		}
+
+		heap_fence_put(wait);
+		heap_fence_put(submit);
+
+		if (err < 0)
+			break;
+
+		num_fences += count;
+		num_waits++;
+
+		cond_resched();
+	}
+
+	atomic_long_add(num_fences, &t->num_fences);
+	atomic_long_add(num_waits, &t->num_waits);
+
+	kfree(order);
+out_requests:
+	kfree(requests);
+	return err;
+}
+
+static int mock_breadcrumbs_smoketest(void *arg)
+{
+	struct drm_i915_private *i915 = arg;
+	struct smoketest t = {
+		.engine = i915->engine[RCS],
+		.ncontexts = 1024,
+		.max_batch = 1024,
+		.request_alloc = __mock_request_alloc
+	};
+	unsigned int ncpus = num_online_cpus();
+	struct task_struct **threads;
+	unsigned int n;
+	int ret = 0;
+
+	threads = kmalloc_array(ncpus, sizeof(*threads), GFP_KERNEL);
+	if (!threads)
+		return -ENOMEM;
+
+	t.contexts =
+		kmalloc_array(t.ncontexts, sizeof(*t.contexts), GFP_KERNEL);
+	if (!t.contexts) {
+		ret = -ENOMEM;
+		goto out_threads;
+	}
+
+	mutex_lock(&t.engine->i915->drm.struct_mutex);
+	for (n = 0; n < t.ncontexts; n++) {
+		t.contexts[n] = mock_context(t.engine->i915, "mock");
+		if (!t.contexts[n]) {
+			ret = -ENOMEM;
+			goto out_contexts;
+		}
+	}
+
+	for (n = 0; n < ncpus; n++) {
+		threads[n] = kthread_run(__igt_breadcrumbs_smoketest,
+					 &t, "igt/%d", n);
+		if (IS_ERR(threads[n])) {
+			ret = PTR_ERR(threads[n]);
+			ncpus = n;
+			break;
+		}
+
+		get_task_struct(threads[n]);
+	}
+	mutex_unlock(&t.engine->i915->drm.struct_mutex);
+
+	msleep(jiffies_to_msecs(i915_selftest.timeout_jiffies));
+
+	for (n = 0; n < ncpus; n++) {
+		int err;
+
+		err = kthread_stop(threads[n]);
+		if (err < 0 && !ret)
+			ret = err;
+
+		put_task_struct(threads[n]);
+	}
+	pr_info("Completed %lu waits for %lu fence across %d cpus\n",
+		atomic_long_read(&t.num_waits),
+		atomic_long_read(&t.num_fences),
+		ncpus);
+
+	mutex_lock(&t.engine->i915->drm.struct_mutex);
+out_contexts:
+	for (n = 0; n < t.ncontexts; n++) {
+		if (!t.contexts[n])
+			break;
+		mock_context_close(t.contexts[n]);
+	}
+	mutex_unlock(&t.engine->i915->drm.struct_mutex);
+	kfree(t.contexts);
+out_threads:
+	kfree(threads);
+
+	return ret;
+}
+
 int i915_request_mock_selftests(void)
 {
 	static const struct i915_subtest tests[] = {
@@ -253,6 +489,7 @@ int i915_request_mock_selftests(void)
 		SUBTEST(igt_wait_request),
 		SUBTEST(igt_fence_wait),
 		SUBTEST(igt_request_rewind),
+		SUBTEST(mock_breadcrumbs_smoketest),
 	};
 	struct drm_i915_private *i915;
 	intel_wakeref_t wakeref;
@@ -872,6 +1109,166 @@ static int live_sequential_engines(void *arg)
 	return err;
 }
 
+static int
+max_batches(struct i915_gem_context *ctx, struct intel_engine_cs *engine)
+{
+	struct i915_request *rq;
+	int ret;
+
+	/*
+	 * Before execlists, all contexts share the same ringbuffer. With
+	 * execlists, each context/engine has a separate ringbuffer and
+	 * for the purposes of this test, inexhaustible.
+	 *
+	 * For the global ringbuffer though, we have to be very careful
+	 * that we do not wrap while preventing the execution of requests
+	 * with a unsignaled fence.
+	 */
+	if (HAS_EXECLISTS(ctx->i915))
+		return INT_MAX;
+
+	rq = i915_request_alloc(engine, ctx);
+	if (IS_ERR(rq)) {
+		ret = PTR_ERR(rq);
+	} else {
+		int sz;
+
+		ret = rq->ring->size - rq->reserved_space;
+		i915_request_add(rq);
+
+		sz = rq->ring->emit - rq->head;
+		if (sz < 0)
+			sz += rq->ring->size;
+		ret /= sz;
+		ret /= 2; /* leave half spare, in case of emergency! */
+
+		/* One ring interleaved between requests from all cpus */
+		ret /= num_online_cpus() + 1;
+	}
+
+	return ret;
+}
+
+static int live_breadcrumbs_smoketest(void *arg)
+{
+	struct drm_i915_private *i915 = arg;
+	struct smoketest t[I915_NUM_ENGINES];
+	unsigned int ncpus = num_online_cpus();
+	unsigned long num_waits, num_fences;
+	struct intel_engine_cs *engine;
+	struct task_struct **threads;
+	enum intel_engine_id id;
+	intel_wakeref_t wakeref;
+	struct drm_file *file;
+	struct live_test live;
+	unsigned int n;
+	int ret = 0;
+
+	wakeref = intel_runtime_pm_get(i915);
+
+	file = mock_file(i915);
+	if (IS_ERR(file)) {
+		ret = PTR_ERR(file);
+		goto out_rpm;
+	}
+
+	threads = kcalloc(ncpus * I915_NUM_ENGINES,
+			  sizeof(*threads),
+			  GFP_KERNEL);
+	if (!threads)
+		return -ENOMEM;
+
+	memset(&t[0], 0, sizeof(t[0]));
+	t[0].request_alloc = __live_request_alloc;
+	t[0].ncontexts = 64;
+	t[0].contexts = kmalloc_array(t[0].ncontexts,
+				      sizeof(*t[0].contexts),
+				      GFP_KERNEL);
+	if (!t[0].contexts) {
+		ret = -ENOMEM;
+		goto out_threads;
+	}
+
+	mutex_lock(&i915->drm.struct_mutex);
+	for (n = 0; n < t[0].ncontexts; n++) {
+		t[0].contexts[n] = live_context(i915, file);
+		if (!t[0].contexts[n]) {
+			ret = -ENOMEM;
+			goto out_contexts;
+		}
+	}
+
+	ret = begin_live_test(&live, i915, __func__, "");
+	if (ret)
+		goto out_contexts;
+
+	for_each_engine(engine, i915, id) {
+		t[id] = t[0];
+		t[id].engine = engine;
+		t[id].max_batch = max_batches(t[0].contexts[0], engine);
+		if (t[id].max_batch < 0) {
+			ret = t[id].max_batch;
+			goto out_flush;
+		}
+		pr_debug("Limiting batches to %d requests on %s\n",
+			 t[id].max_batch, engine->name);
+
+		for (n = 0; n < ncpus; n++) {
+			struct task_struct *tsk;
+
+			tsk = kthread_run(__igt_breadcrumbs_smoketest,
+					  &t[id], "igt/%d.%d", id, n);
+			if (IS_ERR(tsk)) {
+				ret = PTR_ERR(tsk);
+				goto out_flush;
+			}
+
+			get_task_struct(tsk);
+			threads[id * ncpus + n] = tsk;
+		}
+	}
+	mutex_unlock(&i915->drm.struct_mutex);
+
+	msleep(jiffies_to_msecs(i915_selftest.timeout_jiffies));
+
+out_flush:
+	num_waits = 0;
+	num_fences = 0;
+	for_each_engine(engine, i915, id) {
+		for (n = 0; n < ncpus; n++) {
+			struct task_struct *tsk = threads[id * ncpus + n];
+			int err;
+
+			if (!tsk)
+				continue;
+
+			err = kthread_stop(tsk);
+			if (err < 0 && !ret)
+				ret = err;
+
+			put_task_struct(tsk);
+		}
+
+		num_waits += atomic_long_read(&t[id].num_waits);
+		num_fences += atomic_long_read(&t[id].num_fences);
+	}
+	pr_info("Completed %lu waits for %lu fence across %d engines and %d cpus\n",
+		num_waits, num_fences, RUNTIME_INFO(i915)->num_rings, ncpus);
+
+	mutex_lock(&i915->drm.struct_mutex);
+	ret = end_live_test(&live) ?: ret;
+out_contexts:
+	mutex_unlock(&i915->drm.struct_mutex);
+	kfree(t[0].contexts);
+out_threads:
+	kfree(threads);
+	mock_file_free(i915, file);
+out_rpm:
+	intel_runtime_pm_put(i915, wakeref);
+
+	return ret;
+}
+
 int i915_request_live_selftests(struct drm_i915_private *i915)
 {
 	static const struct i915_subtest tests[] = {
@@ -879,6 +1276,7 @@ int i915_request_live_selftests(struct drm_i915_private *i915)
 		SUBTEST(live_all_engines),
 		SUBTEST(live_sequential_engines),
 		SUBTEST(live_empty_request),
+		SUBTEST(live_breadcrumbs_smoketest),
 	};
 
 	if (i915_terminally_wedged(&i915->gpu_error))
diff --git a/drivers/gpu/drm/i915/selftests/igt_spinner.c b/drivers/gpu/drm/i915/selftests/igt_spinner.c
index 0e70df0230b8..9ebd9225684e 100644
--- a/drivers/gpu/drm/i915/selftests/igt_spinner.c
+++ b/drivers/gpu/drm/i915/selftests/igt_spinner.c
@@ -185,11 +185,6 @@ void igt_spinner_fini(struct igt_spinner *spin)
 
 bool igt_wait_for_spinner(struct igt_spinner *spin, struct i915_request *rq)
 {
-	if (!wait_event_timeout(rq->execute,
-				READ_ONCE(rq->global_seqno),
-				msecs_to_jiffies(10)))
-		return false;
-
 	return !(wait_for_us(i915_seqno_passed(hws_seqno(spin, rq),
 					       rq->fence.seqno),
 			     10) &&
diff --git a/drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c b/drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c
deleted file mode 100644
index f03b407fdbe2..000000000000
--- a/drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c
+++ /dev/null
@@ -1,470 +0,0 @@
-/*
- * Copyright © 2016 Intel Corporation
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice (including the next
- * paragraph) shall be included in all copies or substantial portions of the
- * Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
- * IN THE SOFTWARE.
- *
- */
-
-#include "../i915_selftest.h"
-#include "i915_random.h"
-
-#include "mock_gem_device.h"
-#include "mock_engine.h"
-
-static int check_rbtree(struct intel_engine_cs *engine,
-			const unsigned long *bitmap,
-			const struct intel_wait *waiters,
-			const int count)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-	struct rb_node *rb;
-	int n;
-
-	if (&b->irq_wait->node != rb_first(&b->waiters)) {
-		pr_err("First waiter does not match first element of wait-tree\n");
-		return -EINVAL;
-	}
-
-	n = find_first_bit(bitmap, count);
-	for (rb = rb_first(&b->waiters); rb; rb = rb_next(rb)) {
-		struct intel_wait *w = container_of(rb, typeof(*w), node);
-		int idx = w - waiters;
-
-		if (!test_bit(idx, bitmap)) {
-			pr_err("waiter[%d, seqno=%d] removed but still in wait-tree\n",
-			       idx, w->seqno);
-			return -EINVAL;
-		}
-
-		if (n != idx) {
-			pr_err("waiter[%d, seqno=%d] does not match expected next element in tree [%d]\n",
-			       idx, w->seqno, n);
-			return -EINVAL;
-		}
-
-		n = find_next_bit(bitmap, count, n + 1);
-	}
-
-	return 0;
-}
-
-static int check_completion(struct intel_engine_cs *engine,
-			    const unsigned long *bitmap,
-			    const struct intel_wait *waiters,
-			    const int count)
-{
-	int n;
-
-	for (n = 0; n < count; n++) {
-		if (intel_wait_complete(&waiters[n]) != !!test_bit(n, bitmap))
-			continue;
-
-		pr_err("waiter[%d, seqno=%d] is %s, but expected %s\n",
-		       n, waiters[n].seqno,
-		       intel_wait_complete(&waiters[n]) ? "complete" : "active",
-		       test_bit(n, bitmap) ? "active" : "complete");
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-static int check_rbtree_empty(struct intel_engine_cs *engine)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-
-	if (b->irq_wait) {
-		pr_err("Empty breadcrumbs still has a waiter\n");
-		return -EINVAL;
-	}
-
-	if (!RB_EMPTY_ROOT(&b->waiters)) {
-		pr_err("Empty breadcrumbs, but wait-tree not empty\n");
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-static int igt_random_insert_remove(void *arg)
-{
-	const u32 seqno_bias = 0x1000;
-	I915_RND_STATE(prng);
-	struct intel_engine_cs *engine = arg;
-	struct intel_wait *waiters;
-	const int count = 4096;
-	unsigned int *order;
-	unsigned long *bitmap;
-	int err = -ENOMEM;
-	int n;
-
-	mock_engine_reset(engine);
-
-	waiters = kvmalloc_array(count, sizeof(*waiters), GFP_KERNEL);
-	if (!waiters)
-		goto out_engines;
-
-	bitmap = kcalloc(DIV_ROUND_UP(count, BITS_PER_LONG), sizeof(*bitmap),
-			 GFP_KERNEL);
-	if (!bitmap)
-		goto out_waiters;
-
-	order = i915_random_order(count, &prng);
-	if (!order)
-		goto out_bitmap;
-
-	for (n = 0; n < count; n++)
-		intel_wait_init_for_seqno(&waiters[n], seqno_bias + n);
-
-	err = check_rbtree(engine, bitmap, waiters, count);
-	if (err)
-		goto out_order;
-
-	/* Add and remove waiters into the rbtree in random order. At each
-	 * step, we verify that the rbtree is correctly ordered.
-	 */
-	for (n = 0; n < count; n++) {
-		int i = order[n];
-
-		intel_engine_add_wait(engine, &waiters[i]);
-		__set_bit(i, bitmap);
-
-		err = check_rbtree(engine, bitmap, waiters, count);
-		if (err)
-			goto out_order;
-	}
-
-	i915_random_reorder(order, count, &prng);
-	for (n = 0; n < count; n++) {
-		int i = order[n];
-
-		intel_engine_remove_wait(engine, &waiters[i]);
-		__clear_bit(i, bitmap);
-
-		err = check_rbtree(engine, bitmap, waiters, count);
-		if (err)
-			goto out_order;
-	}
-
-	err = check_rbtree_empty(engine);
-out_order:
-	kfree(order);
-out_bitmap:
-	kfree(bitmap);
-out_waiters:
-	kvfree(waiters);
-out_engines:
-	mock_engine_flush(engine);
-	return err;
-}
-
-static int igt_insert_complete(void *arg)
-{
-	const u32 seqno_bias = 0x1000;
-	struct intel_engine_cs *engine = arg;
-	struct intel_wait *waiters;
-	const int count = 4096;
-	unsigned long *bitmap;
-	int err = -ENOMEM;
-	int n, m;
-
-	mock_engine_reset(engine);
-
-	waiters = kvmalloc_array(count, sizeof(*waiters), GFP_KERNEL);
-	if (!waiters)
-		goto out_engines;
-
-	bitmap = kcalloc(DIV_ROUND_UP(count, BITS_PER_LONG), sizeof(*bitmap),
-			 GFP_KERNEL);
-	if (!bitmap)
-		goto out_waiters;
-
-	for (n = 0; n < count; n++) {
-		intel_wait_init_for_seqno(&waiters[n], n + seqno_bias);
-		intel_engine_add_wait(engine, &waiters[n]);
-		__set_bit(n, bitmap);
-	}
-	err = check_rbtree(engine, bitmap, waiters, count);
-	if (err)
-		goto out_bitmap;
-
-	/* On each step, we advance the seqno so that several waiters are then
-	 * complete (we increase the seqno by increasingly larger values to
-	 * retire more and more waiters at once). All retired waiters should
-	 * be woken and removed from the rbtree, and so that we check.
-	 */
-	for (n = 0; n < count; n = m) {
-		int seqno = 2 * n;
-
-		GEM_BUG_ON(find_first_bit(bitmap, count) != n);
-
-		if (intel_wait_complete(&waiters[n])) {
-			pr_err("waiter[%d, seqno=%d] completed too early\n",
-			       n, waiters[n].seqno);
-			err = -EINVAL;
-			goto out_bitmap;
-		}
-
-		/* complete the following waiters */
-		mock_seqno_advance(engine, seqno + seqno_bias);
-		for (m = n; m <= seqno; m++) {
-			if (m == count)
-				break;
-
-			GEM_BUG_ON(!test_bit(m, bitmap));
-			__clear_bit(m, bitmap);
-		}
-
-		intel_engine_remove_wait(engine, &waiters[n]);
-		RB_CLEAR_NODE(&waiters[n].node);
-
-		err = check_rbtree(engine, bitmap, waiters, count);
-		if (err) {
-			pr_err("rbtree corrupt after seqno advance to %d\n",
-			       seqno + seqno_bias);
-			goto out_bitmap;
-		}
-
-		err = check_completion(engine, bitmap, waiters, count);
-		if (err) {
-			pr_err("completions after seqno advance to %d failed\n",
-			       seqno + seqno_bias);
-			goto out_bitmap;
-		}
-	}
-
-	err = check_rbtree_empty(engine);
-out_bitmap:
-	kfree(bitmap);
-out_waiters:
-	kvfree(waiters);
-out_engines:
-	mock_engine_flush(engine);
-	return err;
-}
-
-struct igt_wakeup {
-	struct task_struct *tsk;
-	atomic_t *ready, *set, *done;
-	struct intel_engine_cs *engine;
-	unsigned long flags;
-#define STOP 0
-#define IDLE 1
-	wait_queue_head_t *wq;
-	u32 seqno;
-};
-
-static bool wait_for_ready(struct igt_wakeup *w)
-{
-	DEFINE_WAIT(ready);
-
-	set_bit(IDLE, &w->flags);
-	if (atomic_dec_and_test(w->done))
-		wake_up_var(w->done);
-
-	if (test_bit(STOP, &w->flags))
-		goto out;
-
-	for (;;) {
-		prepare_to_wait(w->wq, &ready, TASK_INTERRUPTIBLE);
-		if (atomic_read(w->ready) == 0)
-			break;
-
-		schedule();
-	}
-	finish_wait(w->wq, &ready);
-
-out:
-	clear_bit(IDLE, &w->flags);
-	if (atomic_dec_and_test(w->set))
-		wake_up_var(w->set);
-
-	return !test_bit(STOP, &w->flags);
-}
-
-static int igt_wakeup_thread(void *arg)
-{
-	struct igt_wakeup *w = arg;
-	struct intel_wait wait;
-
-	while (wait_for_ready(w)) {
-		GEM_BUG_ON(kthread_should_stop());
-
-		intel_wait_init_for_seqno(&wait, w->seqno);
-		intel_engine_add_wait(w->engine, &wait);
-		for (;;) {
-			set_current_state(TASK_UNINTERRUPTIBLE);
-			if (i915_seqno_passed(intel_engine_get_seqno(w->engine),
-					      w->seqno))
-				break;
-
-			if (test_bit(STOP, &w->flags)) /* emergency escape */
-				break;
-
-			schedule();
-		}
-		intel_engine_remove_wait(w->engine, &wait);
-		__set_current_state(TASK_RUNNING);
-	}
-
-	return 0;
-}
-
-static void igt_wake_all_sync(atomic_t *ready,
-			      atomic_t *set,
-			      atomic_t *done,
-			      wait_queue_head_t *wq,
-			      int count)
-{
-	atomic_set(set, count);
-	atomic_set(ready, 0);
-	wake_up_all(wq);
-
-	wait_var_event(set, !atomic_read(set));
-	atomic_set(ready, count);
-	atomic_set(done, count);
-}
-
-static int igt_wakeup(void *arg)
-{
-	I915_RND_STATE(prng);
-	struct intel_engine_cs *engine = arg;
-	struct igt_wakeup *waiters;
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
-	const int count = 4096;
-	const u32 max_seqno = count / 4;
-	atomic_t ready, set, done;
-	int err = -ENOMEM;
-	int n, step;
-
-	mock_engine_reset(engine);
-
-	waiters = kvmalloc_array(count, sizeof(*waiters), GFP_KERNEL);
-	if (!waiters)
-		goto out_engines;
-
-	/* Create a large number of threads, each waiting on a random seqno.
-	 * Multiple waiters will be waiting for the same seqno.
-	 */
-	atomic_set(&ready, count);
-	for (n = 0; n < count; n++) {
-		waiters[n].wq = &wq;
-		waiters[n].ready = &ready;
-		waiters[n].set = &set;
-		waiters[n].done = &done;
-		waiters[n].engine = engine;
-		waiters[n].flags = BIT(IDLE);
-
-		waiters[n].tsk = kthread_run(igt_wakeup_thread, &waiters[n],
-					     "i915/igt:%d", n);
-		if (IS_ERR(waiters[n].tsk))
-			goto out_waiters;
-
-		get_task_struct(waiters[n].tsk);
-	}
-
-	for (step = 1; step <= max_seqno; step <<= 1) {
-		u32 seqno;
-
-		/* The waiter threads start paused as we assign them a random
-		 * seqno and reset the engine. Once the engine is reset,
-		 * we signal that the threads may begin their wait upon their
-		 * seqno.
-		 */
-		for (n = 0; n < count; n++) {
-			GEM_BUG_ON(!test_bit(IDLE, &waiters[n].flags));
-			waiters[n].seqno =
-				1 + prandom_u32_state(&prng) % max_seqno;
-		}
-		mock_seqno_advance(engine, 0);
-		igt_wake_all_sync(&ready, &set, &done, &wq, count);
-
-		/* Simulate the GPU doing chunks of work, with one or more
-		 * seqno appearing to finish at the same time. A random number
-		 * of threads will be waiting upon the update and hopefully be
-		 * woken.
-		 */
-		for (seqno = 1; seqno <= max_seqno + step; seqno += step) {
-			usleep_range(50, 500);
-			mock_seqno_advance(engine, seqno);
-		}
-		GEM_BUG_ON(intel_engine_get_seqno(engine) < 1 + max_seqno);
-
-		/* With the seqno now beyond any of the waiting threads, they
-		 * should all be woken, see that they are complete and signal
-		 * that they are ready for the next test. We wait until all
-		 * threads are complete and waiting for us (i.e. not a seqno).
-		 */
-		if (!wait_var_event_timeout(&done,
-					    !atomic_read(&done), 10 * HZ)) {
-			pr_err("Timed out waiting for %d remaining waiters\n",
-			       atomic_read(&done));
-			err = -ETIMEDOUT;
-			break;
-		}
-
-		err = check_rbtree_empty(engine);
-		if (err)
-			break;
-	}
-
-out_waiters:
-	for (n = 0; n < count; n++) {
-		if (IS_ERR(waiters[n].tsk))
-			break;
-
-		set_bit(STOP, &waiters[n].flags);
-	}
-	mock_seqno_advance(engine, INT_MAX); /* wakeup any broken waiters */
-	igt_wake_all_sync(&ready, &set, &done, &wq, n);
-
-	for (n = 0; n < count; n++) {
-		if (IS_ERR(waiters[n].tsk))
-			break;
-
-		kthread_stop(waiters[n].tsk);
-		put_task_struct(waiters[n].tsk);
-	}
-
-	kvfree(waiters);
-out_engines:
-	mock_engine_flush(engine);
-	return err;
-}
-
-int intel_breadcrumbs_mock_selftests(void)
-{
-	static const struct i915_subtest tests[] = {
-		SUBTEST(igt_random_insert_remove),
-		SUBTEST(igt_insert_complete),
-		SUBTEST(igt_wakeup),
-	};
-	struct drm_i915_private *i915;
-	int err;
-
-	i915 = mock_gem_device();
-	if (!i915)
-		return -ENOMEM;
-
-	err = i915_subtests(tests, i915->engine[RCS]);
-	drm_dev_put(&i915->drm);
-
-	return err;
-}
diff --git a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
index 9d0cc9d63a1e..128d37bba1ac 100644
--- a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
+++ b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
@@ -1127,7 +1127,7 @@ static int __igt_reset_evict_vma(struct drm_i915_private *i915,
 
 	wait_for_completion(&arg.completion);
 
-	if (wait_for(waitqueue_active(&rq->execute), 10)) {
+	if (wait_for(!list_empty(&rq->fence.cb_list), 10)) {
 		struct drm_printer p = drm_info_printer(i915->drm.dev);
 
 		pr_err("igt/evict_vma kthread did not wait\n");
diff --git a/drivers/gpu/drm/i915/selftests/lib_sw_fence.c b/drivers/gpu/drm/i915/selftests/lib_sw_fence.c
index b26f07b55d86..2bfa72c1654b 100644
--- a/drivers/gpu/drm/i915/selftests/lib_sw_fence.c
+++ b/drivers/gpu/drm/i915/selftests/lib_sw_fence.c
@@ -76,3 +76,57 @@ void timed_fence_fini(struct timed_fence *tf)
 	destroy_timer_on_stack(&tf->timer);
 	i915_sw_fence_fini(&tf->fence);
 }
+
+struct heap_fence {
+	struct i915_sw_fence fence;
+	union {
+		struct kref ref;
+		struct rcu_head rcu;
+	};
+};
+
+static int __i915_sw_fence_call
+heap_fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
+{
+	struct heap_fence *h = container_of(fence, typeof(*h), fence);
+
+	switch (state) {
+	case FENCE_COMPLETE:
+		break;
+
+	case FENCE_FREE:
+		heap_fence_put(&h->fence);
+	}
+
+	return NOTIFY_DONE;
+}
+
+struct i915_sw_fence *heap_fence_create(gfp_t gfp)
+{
+	struct heap_fence *h;
+
+	h = kmalloc(sizeof(*h), gfp);
+	if (!h)
+		return NULL;
+
+	i915_sw_fence_init(&h->fence, heap_fence_notify);
+	refcount_set(&h->ref.refcount, 2);
+
+	return &h->fence;
+}
+
+static void heap_fence_release(struct kref *ref)
+{
+	struct heap_fence *h = container_of(ref, typeof(*h), ref);
+
+	i915_sw_fence_fini(&h->fence);
+
+	kfree_rcu(h, rcu);
+}
+
+void heap_fence_put(struct i915_sw_fence *fence)
+{
+	struct heap_fence *h = container_of(fence, typeof(*h), fence);
+
+	kref_put(&h->ref, heap_fence_release);
+}
diff --git a/drivers/gpu/drm/i915/selftests/lib_sw_fence.h b/drivers/gpu/drm/i915/selftests/lib_sw_fence.h
index 474aafb92ae1..1f9927e10f3a 100644
--- a/drivers/gpu/drm/i915/selftests/lib_sw_fence.h
+++ b/drivers/gpu/drm/i915/selftests/lib_sw_fence.h
@@ -39,4 +39,7 @@ struct timed_fence {
 void timed_fence_init(struct timed_fence *tf, unsigned long expires);
 void timed_fence_fini(struct timed_fence *tf);
 
+struct i915_sw_fence *heap_fence_create(gfp_t gfp);
+void heap_fence_put(struct i915_sw_fence *fence);
+
 #endif /* _LIB_SW_FENCE_H_ */
diff --git a/drivers/gpu/drm/i915/selftests/mock_context.c b/drivers/gpu/drm/i915/selftests/mock_context.c
index d937bdff26f9..e4db9a31b510 100644
--- a/drivers/gpu/drm/i915/selftests/mock_context.c
+++ b/drivers/gpu/drm/i915/selftests/mock_context.c
@@ -49,6 +49,8 @@ mock_context(struct drm_i915_private *i915,
 		struct intel_context *ce = &ctx->__engine[n];
 
 		ce->gem_context = ctx;
+		INIT_LIST_HEAD(&ce->signal_link);
+		INIT_LIST_HEAD(&ce->signals);
 	}
 
 	ret = i915_gem_context_pin_hw_id(ctx);
diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
index b4b61056b227..c1cd8b27b32a 100644
--- a/drivers/gpu/drm/i915/selftests/mock_engine.c
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
@@ -75,25 +75,27 @@ static struct mock_request *first_request(struct mock_engine *engine)
 					link);
 }
 
-static void advance(struct mock_engine *engine,
-		    struct mock_request *request)
+static void advance(struct mock_request *request)
 {
 	list_del_init(&request->link);
 	i915_request_fake_complete(&request->base);
-	mock_seqno_advance(&engine->base, request->base.global_seqno);
+	intel_engine_write_global_seqno(request->base.engine,
+					request->base.global_seqno);
+	intel_engine_queue_breadcrumbs(request->base.engine);
 }
 
 static void hw_delay_complete(struct timer_list *t)
 {
 	struct mock_engine *engine = from_timer(engine, t, hw_delay);
 	struct mock_request *request;
+	unsigned long flags;
 
-	spin_lock(&engine->hw_lock);
+	spin_lock_irqsave(&engine->hw_lock, flags);
 
 	/* Timer fired, first request is complete */
 	request = first_request(engine);
 	if (request)
-		advance(engine, request);
+		advance(request);
 
 	/*
 	 * Also immediately signal any subsequent 0-delay requests, but
@@ -105,10 +107,10 @@ static void hw_delay_complete(struct timer_list *t)
 			break;
 		}
 
-		advance(engine, request);
+		advance(request);
 	}
 
-	spin_unlock(&engine->hw_lock);
+	spin_unlock_irqrestore(&engine->hw_lock, flags);
 }
 
 static void mock_context_unpin(struct intel_context *ce)
@@ -179,19 +181,20 @@ static void mock_submit_request(struct i915_request *request)
 	struct mock_request *mock = container_of(request, typeof(*mock), base);
 	struct mock_engine *engine =
 		container_of(request->engine, typeof(*engine), base);
+	unsigned long flags;
 
 	i915_request_submit(request);
 	GEM_BUG_ON(!request->global_seqno);
 
-	spin_lock_irq(&engine->hw_lock);
+	spin_lock_irqsave(&engine->hw_lock, flags);
 	list_add_tail(&mock->link, &engine->hw_queue);
 	if (mock->link.prev == &engine->hw_queue) {
 		if (mock->delay)
 			mod_timer(&engine->hw_delay, jiffies + mock->delay);
 		else
-			advance(engine, mock);
+			advance(mock);
 	}
-	spin_unlock_irq(&engine->hw_lock);
+	spin_unlock_irqrestore(&engine->hw_lock, flags);
 }
 
 struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
@@ -255,12 +258,13 @@ void mock_engine_flush(struct intel_engine_cs *engine)
 
 	spin_lock_irq(&mock->hw_lock);
 	list_for_each_entry_safe(request, rn, &mock->hw_queue, link)
-		advance(mock, request);
+		advance(request);
 	spin_unlock_irq(&mock->hw_lock);
 }
 
 void mock_engine_reset(struct intel_engine_cs *engine)
 {
+	intel_engine_write_global_seqno(engine, 0);
 }
 
 void mock_engine_free(struct intel_engine_cs *engine)
diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.h b/drivers/gpu/drm/i915/selftests/mock_engine.h
index 133d0c21790d..b9cc3a245f16 100644
--- a/drivers/gpu/drm/i915/selftests/mock_engine.h
+++ b/drivers/gpu/drm/i915/selftests/mock_engine.h
@@ -46,10 +46,4 @@ void mock_engine_flush(struct intel_engine_cs *engine);
 void mock_engine_reset(struct intel_engine_cs *engine);
 void mock_engine_free(struct intel_engine_cs *engine);
 
-static inline void mock_seqno_advance(struct intel_engine_cs *engine, u32 seqno)
-{
-	intel_write_status_page(engine, I915_GEM_HWS_INDEX, seqno);
-	intel_engine_wakeup(engine);
-}
-
 #endif /* !__MOCK_ENGINE_H__ */
-- 
2.20.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 50+ messages in thread

* [PATCH 23/23] drm/i915: Drop fake breadcrumb irq
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (21 preceding siblings ...)
  2019-01-17 14:35 ` [PATCH 22/23] drm/i915: Replace global breadcrumbs with per-context interrupt tracking Chris Wilson
@ 2019-01-17 14:35 ` Chris Wilson
  2019-01-17 14:37 ` Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (4 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:35 UTC (permalink / raw)
  To: intel-gfx

Missed breadcrumb detection is defunct due to the tight coupling with
dma_fence signaling and the myriad ways we may signal fences from
everywhere but from an interrupt, i.e. we frequently signal a fence
before we even see its interrupt. This means that even if we miss an
interrupt for a fence, it still is signaled before our breadcrumb
hangcheck fires, so simplify the breadcrumb hangchecking by moving it
into the GPU hangcheck and forgo fake interrupts.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_debugfs.c           |  94 +----------
 drivers/gpu/drm/i915/i915_gpu_error.c         |   2 -
 drivers/gpu/drm/i915/i915_gpu_error.h         |   5 -
 drivers/gpu/drm/i915/intel_breadcrumbs.c      | 147 +-----------------
 drivers/gpu/drm/i915/intel_hangcheck.c        |   2 +
 drivers/gpu/drm/i915/intel_ringbuffer.h       |   5 -
 .../gpu/drm/i915/selftests/i915_gem_context.c |   7 -
 drivers/gpu/drm/i915/selftests/i915_request.c |   7 -
 8 files changed, 6 insertions(+), 263 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index a8830d7d1617..3c89ab5ea480 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1319,9 +1319,7 @@ static int i915_hangcheck_info(struct seq_file *m, void *unused)
 		seq_printf(m, "\tseqno = %x [current %x, last %x]\n",
 			   engine->hangcheck.seqno, seqno[id],
 			   intel_engine_last_submit(engine));
-		seq_printf(m, "\tfake irq active? %s, stalled? %s, wedged? %s\n",
-			   yesno(test_bit(engine->id,
-					  &dev_priv->gpu_error.missed_irq_rings)),
+		seq_printf(m, "\tstalled? %s, wedged? %s\n",
 			   yesno(engine->hangcheck.stalled),
 			   yesno(engine->hangcheck.wedged));
 
@@ -3886,94 +3884,6 @@ DEFINE_SIMPLE_ATTRIBUTE(i915_wedged_fops,
 			i915_wedged_get, i915_wedged_set,
 			"%llu\n");
 
-static int
-fault_irq_set(struct drm_i915_private *i915,
-	      unsigned long *irq,
-	      unsigned long val)
-{
-	int err;
-
-	err = mutex_lock_interruptible(&i915->drm.struct_mutex);
-	if (err)
-		return err;
-
-	err = i915_gem_wait_for_idle(i915,
-				     I915_WAIT_LOCKED |
-				     I915_WAIT_INTERRUPTIBLE,
-				     MAX_SCHEDULE_TIMEOUT);
-	if (err)
-		goto err_unlock;
-
-	*irq = val;
-	mutex_unlock(&i915->drm.struct_mutex);
-
-	/* Flush idle worker to disarm irq */
-	drain_delayed_work(&i915->gt.idle_work);
-
-	return 0;
-
-err_unlock:
-	mutex_unlock(&i915->drm.struct_mutex);
-	return err;
-}
-
-static int
-i915_ring_missed_irq_get(void *data, u64 *val)
-{
-	struct drm_i915_private *dev_priv = data;
-
-	*val = dev_priv->gpu_error.missed_irq_rings;
-	return 0;
-}
-
-static int
-i915_ring_missed_irq_set(void *data, u64 val)
-{
-	struct drm_i915_private *i915 = data;
-
-	return fault_irq_set(i915, &i915->gpu_error.missed_irq_rings, val);
-}
-
-DEFINE_SIMPLE_ATTRIBUTE(i915_ring_missed_irq_fops,
-			i915_ring_missed_irq_get, i915_ring_missed_irq_set,
-			"0x%08llx\n");
-
-static int
-i915_ring_test_irq_get(void *data, u64 *val)
-{
-	struct drm_i915_private *dev_priv = data;
-
-	*val = dev_priv->gpu_error.test_irq_rings;
-
-	return 0;
-}
-
-static int
-i915_ring_test_irq_set(void *data, u64 val)
-{
-	struct drm_i915_private *i915 = data;
-
-	/* GuC keeps the user interrupt permanently enabled for submission */
-	if (USES_GUC_SUBMISSION(i915))
-		return -ENODEV;
-
-	/*
-	 * From icl, we can no longer individually mask interrupt generation
-	 * from each engine.
-	 */
-	if (INTEL_GEN(i915) >= 11)
-		return -ENODEV;
-
-	val &= INTEL_INFO(i915)->ring_mask;
-	DRM_DEBUG_DRIVER("Masking interrupts on rings 0x%08llx\n", val);
-
-	return fault_irq_set(i915, &i915->gpu_error.test_irq_rings, val);
-}
-
-DEFINE_SIMPLE_ATTRIBUTE(i915_ring_test_irq_fops,
-			i915_ring_test_irq_get, i915_ring_test_irq_set,
-			"0x%08llx\n");
-
 #define DROP_UNBOUND	BIT(0)
 #define DROP_BOUND	BIT(1)
 #define DROP_RETIRE	BIT(2)
@@ -4735,8 +4645,6 @@ static const struct i915_debugfs_files {
 } i915_debugfs_files[] = {
 	{"i915_wedged", &i915_wedged_fops},
 	{"i915_cache_sharing", &i915_cache_sharing_fops},
-	{"i915_ring_missed_irq", &i915_ring_missed_irq_fops},
-	{"i915_ring_test_irq", &i915_ring_test_irq_fops},
 	{"i915_gem_drop_caches", &i915_drop_caches_fops},
 #if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
 	{"i915_error_state", &i915_error_state_fops},
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index c6057126bb53..ccdb412f6a75 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -721,8 +721,6 @@ static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
 	err_printf(m, "FORCEWAKE: 0x%08x\n", error->forcewake);
 	err_printf(m, "DERRMR: 0x%08x\n", error->derrmr);
 	err_printf(m, "CCID: 0x%08x\n", error->ccid);
-	err_printf(m, "Missed interrupts: 0x%08lx\n",
-		   m->i915->gpu_error.missed_irq_rings);
 
 	for (i = 0; i < error->nfence; i++)
 		err_printf(m, "  fence[%d] = %08llx\n", i, error->fence[i]);
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.h b/drivers/gpu/drm/i915/i915_gpu_error.h
index cb6a6add543e..5231d433a880 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.h
+++ b/drivers/gpu/drm/i915/i915_gpu_error.h
@@ -205,8 +205,6 @@ struct i915_gpu_error {
 
 	atomic_t pending_fb_pin;
 
-	unsigned long missed_irq_rings;
-
 	/**
 	 * State variable controlling the reset flow and count
 	 *
@@ -275,9 +273,6 @@ struct i915_gpu_error {
 	 */
 	wait_queue_head_t reset_queue;
 
-	/* For missed irq/seqno simulation. */
-	unsigned long test_irq_rings;
-
 	struct i915_gpu_restart *restart;
 };
 
diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c
index f9fd967bb50c..f1bd7e51d951 100644
--- a/drivers/gpu/drm/i915/intel_breadcrumbs.c
+++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
@@ -94,7 +94,6 @@ bool intel_engine_breadcrumbs_irq(struct intel_engine_cs *engine)
 
 	spin_lock(&b->irq_lock);
 
-	b->irq_fired = true;
 	if (b->irq_armed && list_empty(&b->signalers))
 		__intel_breadcrumbs_disarm_irq(b);
 
@@ -158,86 +157,6 @@ static void signal_irq_work(struct irq_work *work)
 	intel_engine_breadcrumbs_irq(engine);
 }
 
-static unsigned long wait_timeout(void)
-{
-	return round_jiffies_up(jiffies + DRM_I915_HANGCHECK_JIFFIES);
-}
-
-static noinline void missed_breadcrumb(struct intel_engine_cs *engine)
-{
-	if (GEM_SHOW_DEBUG()) {
-		struct drm_printer p = drm_debug_printer(__func__);
-
-		intel_engine_dump(engine, &p,
-				  "%s missed breadcrumb at %pS\n",
-				  engine->name, __builtin_return_address(0));
-	}
-
-	set_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings);
-}
-
-static void intel_breadcrumbs_hangcheck(struct timer_list *t)
-{
-	struct intel_engine_cs *engine =
-		from_timer(engine, t, breadcrumbs.hangcheck);
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-
-	if (!b->irq_armed)
-		return;
-
-	if (b->irq_fired)
-		goto rearm;
-
-	/*
-	 * We keep the hangcheck timer alive until we disarm the irq, even
-	 * if there are no waiters at present.
-	 *
-	 * If the waiter was currently running, assume it hasn't had a chance
-	 * to process the pending interrupt (e.g, low priority task on a loaded
-	 * system) and wait until it sleeps before declaring a missed interrupt.
-	 *
-	 * If the waiter was asleep (and not even pending a wakeup), then we
-	 * must have missed an interrupt as the GPU has stopped advancing
-	 * but we still have a waiter. Assuming all batches complete within
-	 * DRM_I915_HANGCHECK_JIFFIES [1.5s]!
-	 */
-	synchronize_hardirq(engine->i915->drm.irq);
-	if (intel_engine_signal_breadcrumbs(engine)) {
-		missed_breadcrumb(engine);
-		mod_timer(&b->fake_irq, jiffies + 1);
-	} else {
-rearm:
-		b->irq_fired = false;
-		mod_timer(&b->hangcheck, wait_timeout());
-	}
-}
-
-static void intel_breadcrumbs_fake_irq(struct timer_list *t)
-{
-	struct intel_engine_cs *engine =
-		from_timer(engine, t, breadcrumbs.fake_irq);
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-
-	/*
-	 * The timer persists in case we cannot enable interrupts,
-	 * or if we have previously seen seqno/interrupt incoherency
-	 * ("missed interrupt" syndrome, better known as a "missed breadcrumb").
-	 * Here the worker will wake up every jiffie in order to kick the
-	 * oldest waiter to do the coherent seqno check.
-	 */
-
-	if (!intel_engine_signal_breadcrumbs(engine) && !b->irq_armed)
-		return;
-
-	/* If the user has disabled the fake-irq, restore the hangchecking */
-	if (!test_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings)) {
-		mod_timer(&b->hangcheck, wait_timeout());
-		return;
-	}
-
-	mod_timer(&b->fake_irq, jiffies + 1);
-}
-
 void intel_engine_pin_breadcrumbs_irq(struct intel_engine_cs *engine)
 {
 	struct intel_breadcrumbs *b = &engine->breadcrumbs;
@@ -260,43 +179,14 @@ void intel_engine_unpin_breadcrumbs_irq(struct intel_engine_cs *engine)
 	spin_unlock_irq(&b->irq_lock);
 }
 
-static bool use_fake_irq(const struct intel_breadcrumbs *b)
-{
-	const struct intel_engine_cs *engine =
-		container_of(b, struct intel_engine_cs, breadcrumbs);
-
-	if (!test_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings))
-		return false;
-
-	/*
-	 * Only start with the heavy weight fake irq timer if we have not
-	 * seen any interrupts since enabling it the first time. If the
-	 * interrupts are still arriving, it means we made a mistake in our
-	 * engine->seqno_barrier(), a timing error that should be transient
-	 * and unlikely to reoccur.
-	 */
-	return !b->irq_fired;
-}
-
-static void enable_fake_irq(struct intel_breadcrumbs *b)
-{
-	/* Ensure we never sleep indefinitely */
-	if (!b->irq_enabled || use_fake_irq(b))
-		mod_timer(&b->fake_irq, jiffies + 1);
-	else
-		mod_timer(&b->hangcheck, wait_timeout());
-}
-
-static bool __intel_breadcrumbs_arm_irq(struct intel_breadcrumbs *b)
+static void __intel_breadcrumbs_arm_irq(struct intel_breadcrumbs *b)
 {
 	struct intel_engine_cs *engine =
 		container_of(b, struct intel_engine_cs, breadcrumbs);
-	struct drm_i915_private *i915 = engine->i915;
-	bool enabled;
 
 	lockdep_assert_held(&b->irq_lock);
 	if (b->irq_armed)
-		return false;
+		return;
 
 	/*
 	 * The breadcrumb irq will be disarmed on the interrupt after the
@@ -314,16 +204,8 @@ static bool __intel_breadcrumbs_arm_irq(struct intel_breadcrumbs *b)
 	 * the driver is idle) we disarm the breadcrumbs.
 	 */
 
-	/* No interrupts? Kick the waiter every jiffie! */
-	enabled = false;
-	if (!b->irq_enabled++ &&
-	    !test_bit(engine->id, &i915->gpu_error.test_irq_rings)) {
+	if (!b->irq_enabled++)
 		irq_enable(engine);
-		enabled = true;
-	}
-
-	enable_fake_irq(b);
-	return enabled;
 }
 
 void intel_engine_init_breadcrumbs(struct intel_engine_cs *engine)
@@ -334,18 +216,6 @@ void intel_engine_init_breadcrumbs(struct intel_engine_cs *engine)
 	INIT_LIST_HEAD(&b->signalers);
 
 	init_irq_work(&b->irq_work, signal_irq_work);
-
-	timer_setup(&b->fake_irq, intel_breadcrumbs_fake_irq, 0);
-	timer_setup(&b->hangcheck, intel_breadcrumbs_hangcheck, 0);
-}
-
-static void cancel_fake_irq(struct intel_engine_cs *engine)
-{
-	struct intel_breadcrumbs *b = &engine->breadcrumbs;
-
-	del_timer_sync(&b->fake_irq); /* may queue b->hangcheck */
-	del_timer_sync(&b->hangcheck);
-	clear_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings);
 }
 
 void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine)
@@ -355,13 +225,6 @@ void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine)
 
 	spin_lock_irqsave(&b->irq_lock, flags);
 
-	/*
-	 * Leave the fake_irq timer enabled (if it is running), but clear the
-	 * bit so that it turns itself off on its next wake up and goes back
-	 * to the long hangcheck interval if still required.
-	 */
-	clear_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings);
-
 	if (b->irq_enabled)
 		irq_enable(engine);
 	else
@@ -372,7 +235,6 @@ void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine)
 
 void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine)
 {
-	cancel_fake_irq(engine);
 }
 
 bool intel_engine_enable_signaling(struct i915_request *rq)
@@ -454,7 +316,4 @@ void intel_engine_print_breadcrumbs(struct intel_engine_cs *engine,
 		}
 	}
 	spin_unlock_irq(&b->irq_lock);
-
-	if (test_bit(engine->id, &engine->i915->gpu_error.missed_irq_rings))
-		drm_printf(p, "Fake irq active\n");
 }
diff --git a/drivers/gpu/drm/i915/intel_hangcheck.c b/drivers/gpu/drm/i915/intel_hangcheck.c
index 7dc11fcb13de..bc8d884f24bd 100644
--- a/drivers/gpu/drm/i915/intel_hangcheck.c
+++ b/drivers/gpu/drm/i915/intel_hangcheck.c
@@ -271,6 +271,8 @@ static void i915_hangcheck_elapsed(struct work_struct *work)
 	for_each_engine(engine, dev_priv, id) {
 		struct intel_engine_hangcheck hc;
 
+		intel_engine_signal_breadcrumbs(engine);
+
 		hangcheck_load_sample(engine, &hc);
 		hangcheck_accumulate_sample(engine, &hc);
 		hangcheck_store_sample(engine, &hc);
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index ca56816902e6..c1de9d6675c3 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -386,14 +386,9 @@ struct intel_engine_cs {
 
 		struct irq_work irq_work;
 
-		struct timer_list fake_irq; /* used after a missed interrupt */
-		struct timer_list hangcheck; /* detect missed interrupts */
-
-		unsigned int hangcheck_interrupts;
 		unsigned int irq_enabled;
 
 		bool irq_armed;
-		bool irq_fired;
 	} breadcrumbs;
 
 	struct {
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_context.c b/drivers/gpu/drm/i915/selftests/i915_gem_context.c
index 4cba50679607..2cca234fd291 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_context.c
@@ -65,7 +65,6 @@ static int begin_live_test(struct live_test *t,
 		return err;
 	}
 
-	i915->gpu_error.missed_irq_rings = 0;
 	t->reset_global = i915_reset_count(&i915->gpu_error);
 
 	for_each_engine(engine, i915, id)
@@ -103,12 +102,6 @@ static int end_live_test(struct live_test *t)
 		return -EIO;
 	}
 
-	if (i915->gpu_error.missed_irq_rings) {
-		pr_err("%s(%s): Missed interrupts on engines %lx\n",
-		       t->func, t->name, i915->gpu_error.missed_irq_rings);
-		return -EIO;
-	}
-
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/i915/selftests/i915_request.c b/drivers/gpu/drm/i915/selftests/i915_request.c
index 48b6159afe64..5953a47827a7 100644
--- a/drivers/gpu/drm/i915/selftests/i915_request.c
+++ b/drivers/gpu/drm/i915/selftests/i915_request.c
@@ -535,7 +535,6 @@ static int begin_live_test(struct live_test *t,
 		return err;
 	}
 
-	i915->gpu_error.missed_irq_rings = 0;
 	t->reset_count = i915_reset_count(&i915->gpu_error);
 
 	return 0;
@@ -559,12 +558,6 @@ static int end_live_test(struct live_test *t)
 		return -EIO;
 	}
 
-	if (i915->gpu_error.missed_irq_rings) {
-		pr_err("%s(%s): Missed interrupts on engines %lx\n",
-		       t->func, t->name, i915->gpu_error.missed_irq_rings);
-		return -EIO;
-	}
-
 	return 0;
 }
 
-- 
2.20.1

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^ permalink raw reply related	[flat|nested] 50+ messages in thread

* Re: Swapping a single global interrupt handler for a herd
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (22 preceding siblings ...)
  2019-01-17 14:35 ` [PATCH 23/23] drm/i915: Drop fake breadcrumb irq Chris Wilson
@ 2019-01-17 14:37 ` Chris Wilson
  2019-01-17 14:56 ` ✗ Fi.CI.CHECKPATCH: warning for series starting with [01/23] drm/i915: Make all GPU resets atomic Patchwork
                   ` (3 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 14:37 UTC (permalink / raw)
  To: intel-gfx

I wrote something here like...

Just the early part of the series with the HWSP allocation changes
suggested by John. Tvrtko I haven't applied your mutex feedback yet.
-Chris
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* ✗ Fi.CI.CHECKPATCH: warning for series starting with [01/23] drm/i915: Make all GPU resets atomic
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (23 preceding siblings ...)
  2019-01-17 14:37 ` Swapping a single global interrupt handler for a herd Chris Wilson
@ 2019-01-17 14:56 ` Patchwork
  2019-01-17 15:05 ` ✗ Fi.CI.SPARSE: " Patchwork
                   ` (2 subsequent siblings)
  27 siblings, 0 replies; 50+ messages in thread
From: Patchwork @ 2019-01-17 14:56 UTC (permalink / raw)
  To: Chris Wilson; +Cc: intel-gfx

== Series Details ==

Series: series starting with [01/23] drm/i915: Make all GPU resets atomic
URL   : https://patchwork.freedesktop.org/series/55365/
State : warning

== Summary ==

$ dim checkpatch origin/drm-tip
cc34d0c113bf drm/i915: Make all GPU resets atomic
-:23: CHECK:USLEEP_RANGE: usleep_range is preferred over udelay; see Documentation/timers/timers-howto.txt
#23: FILE: drivers/gpu/drm/i915/i915_reset.c:147:
+	udelay(50);

-:29: CHECK:USLEEP_RANGE: usleep_range is preferred over udelay; see Documentation/timers/timers-howto.txt
#29: FILE: drivers/gpu/drm/i915/i915_reset.c:152:
+	udelay(50);

total: 0 errors, 0 warnings, 2 checks, 121 lines checked
84c5d840f63e drm/i915/guc: Disable global reset
13c95ff25011 drm/i915: Remove GPU reset dependence on struct_mutex
-:616: WARNING:MEMORY_BARRIER: memory barrier without comment
#616: FILE: drivers/gpu/drm/i915/i915_reset.c:692:
+	smp_store_mb(i915->gpu_error.restart, NULL);

-:769: WARNING:IF_0: Consider removing the code enclosed by this #if 0 and its #endif
#769: FILE: drivers/gpu/drm/i915/i915_reset.c:920:
+#if 0

total: 0 errors, 2 warnings, 0 checks, 1395 lines checked
b126705eb583 drm/i915/selftests: Trim struct_mutex duration for set-wedged selftest
9c242ce79a77 drm/i915: Issue engine resets onto idle engines
941079fbcd79 drm/i915: Stop tracking MRU activity on VMA
b590cd93b877 drm/i915: Pull VM lists under the VM mutex.
1b8241711cd3 drm/i915: Move vma lookup to its own lock
-:157: WARNING:USE_SPINLOCK_T: struct spinlock should be spinlock_t
#157: FILE: drivers/gpu/drm/i915/i915_gem_object.h:94:
+		struct spinlock lock;

total: 0 errors, 1 warnings, 0 checks, 284 lines checked
178df8680efe drm/i915: Use b->irq_enable() as predicate for mock engine
-:6: ERROR:GIT_COMMIT_ID: Please use git commit description style 'commit <12+ chars of sha1> ("<title line>")' - ie: 'commit d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")'
#6: 
Since commit  d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")

-:10: ERROR:GIT_COMMIT_ID: Please use git commit description style 'commit <12+ chars of sha1> ("<title line>")' - ie: 'commit d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")'
#10: 
References: d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")

total: 2 errors, 0 warnings, 0 checks, 111 lines checked
a6cd7e980da3 drm/i915/selftests: Allocate mock ring/timeline per context
e64538758ef8 drm/i915/selftests: Make evict tolerant of foreign objects
a9fb042af3e7 drm/i915: Always allocate an object/vma for the HWSP
4faf687777c5 drm/i915: Move list of timelines under its own lock
fb705705e39d drm/i915: Introduce concept of per-timeline (context) HWSP
722338216230 drm/i915: Enlarge vma->pin_count
90c17ef7381e drm/i915: Allocate a status page for each timeline
9a2c0d841b87 drm/i915: Share per-timeline HWSP using a slab suballocator
590309e71727 drm/i915: Keep all partially allocated HWSP on a freelist
97e2101df0fe drm/i915: Track the context's seqno in its own timeline HWSP
-:170: CHECK:LINE_SPACING: Please use a blank line after function/struct/union/enum declarations
#170: FILE: drivers/gpu/drm/i915/intel_lrc.c:2042:
 }
+static const int gen8_emit_breadcrumb_sz = 10 + WA_TAIL_DWORDS;

-:201: CHECK:LINE_SPACING: Please use a blank line after function/struct/union/enum declarations
#201: FILE: drivers/gpu/drm/i915/intel_lrc.c:2068:
 }
+static const int gen8_emit_breadcrumb_rcs_sz = 14 + WA_TAIL_DWORDS;

-:227: CHECK:LINE_SPACING: Please use a blank line after function/struct/union/enum declarations
#227: FILE: drivers/gpu/drm/i915/intel_ringbuffer.c:343:
 }
+static const int gen6_rcs_emit_breadcrumb_sz = 18;

-:250: CHECK:LINE_SPACING: Please use a blank line after function/struct/union/enum declarations
#250: FILE: drivers/gpu/drm/i915/intel_ringbuffer.c:450:
 }
+static const int gen7_rcs_emit_breadcrumb_sz = 10;

-:271: CHECK:LINE_SPACING: Please use a blank line after function/struct/union/enum declarations
#271: FILE: drivers/gpu/drm/i915/intel_ringbuffer.c:468:
 }
+static const int gen6_xcs_emit_breadcrumb_sz = 8;

-:299: CHECK:LINE_SPACING: Please use a blank line after function/struct/union/enum declarations
#299: FILE: drivers/gpu/drm/i915/intel_ringbuffer.c:498:
 }
+static const int gen7_xcs_emit_breadcrumb_sz = 10 + GEN7_XCS_WA * 3;

-:351: CHECK:LINE_SPACING: Please use a blank line after function/struct/union/enum declarations
#351: FILE: drivers/gpu/drm/i915/intel_ringbuffer.c:944:
 }
+static const int i9xx_emit_breadcrumb_sz = 8;

-:379: CHECK:LINE_SPACING: Please use a blank line after function/struct/union/enum declarations
#379: FILE: drivers/gpu/drm/i915/intel_ringbuffer.c:972:
 }
+static const int gen5_emit_breadcrumb_sz = GEN5_WA_STORES * 3 + 6;

total: 0 errors, 0 warnings, 8 checks, 397 lines checked
22e584a722b8 drm/i915: Identify active requests
f4d10d8a497c drm/i915: Remove the intel_engine_notify tracepoint
2c07c68932af drm/i915: Replace global breadcrumbs with per-context interrupt tracking
-:18: ERROR:GIT_COMMIT_ID: Please use git commit description style 'commit <12+ chars of sha1> ("<title line>")' - ie: 'commit 688e6c725816 ("drm/i915: Slaughter the thundering i915_wait_request herd")'
#18: 
Before commit 688e6c725816, the solution was simple. Every client waking

-:21: ERROR:GIT_COMMIT_ID: Please use git commit description style 'commit <12+ chars of sha1> ("<title line>")' - ie: 'commit 688e6c725816 ("drm/i915: Slaughter the thundering i915_wait_request herd")'
#21: 
688e6c725816 introduced an rbtree so that only the earliest waiter on

-:49: WARNING:COMMIT_LOG_LONG_LINE: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#49: 
References: 688e6c725816 ("drm/i915: Slaughter the thundering i915_wait_request herd")

-:49: ERROR:GIT_COMMIT_ID: Please use git commit description style 'commit <12+ chars of sha1> ("<title line>")' - ie: 'commit 688e6c725816 ("drm/i915: Slaughter the thundering i915_wait_request herd")'
#49: 
References: 688e6c725816 ("drm/i915: Slaughter the thundering i915_wait_request herd")

-:2012: WARNING:FUNCTION_ARGUMENTS: function definition argument 'struct i915_gem_context *' should also have an identifier name
#2012: FILE: drivers/gpu/drm/i915/selftests/i915_request.c:257:
+	struct i915_request *(*request_alloc)(struct i915_gem_context *,

-:2012: WARNING:FUNCTION_ARGUMENTS: function definition argument 'struct intel_engine_cs *' should also have an identifier name
#2012: FILE: drivers/gpu/drm/i915/selftests/i915_request.c:257:
+	struct i915_request *(*request_alloc)(struct i915_gem_context *,

-:2036: WARNING:LINE_SPACING: Missing a blank line after declarations
#2036: FILE: drivers/gpu/drm/i915/selftests/i915_request.c:281:
+	struct i915_request **requests;
+	I915_RND_STATE(prng);

-:2443: WARNING:FILE_PATH_CHANGES: added, moved or deleted file(s), does MAINTAINERS need updating?
#2443: 
deleted file mode 100644

total: 3 errors, 5 warnings, 0 checks, 2428 lines checked
f7e648e4bba8 drm/i915: Drop fake breadcrumb irq

_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* ✗ Fi.CI.SPARSE: warning for series starting with [01/23] drm/i915: Make all GPU resets atomic
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (24 preceding siblings ...)
  2019-01-17 14:56 ` ✗ Fi.CI.CHECKPATCH: warning for series starting with [01/23] drm/i915: Make all GPU resets atomic Patchwork
@ 2019-01-17 15:05 ` Patchwork
  2019-01-17 15:38 ` ✓ Fi.CI.BAT: success " Patchwork
  2019-01-17 23:36 ` ✗ Fi.CI.IGT: failure " Patchwork
  27 siblings, 0 replies; 50+ messages in thread
From: Patchwork @ 2019-01-17 15:05 UTC (permalink / raw)
  To: Chris Wilson; +Cc: intel-gfx

== Series Details ==

Series: series starting with [01/23] drm/i915: Make all GPU resets atomic
URL   : https://patchwork.freedesktop.org/series/55365/
State : warning

== Summary ==

$ dim sparse origin/drm-tip
Sparse version: v0.5.2
Commit: drm/i915: Make all GPU resets atomic
Okay!

Commit: drm/i915/guc: Disable global reset
Okay!

Commit: drm/i915: Remove GPU reset dependence on struct_mutex
-drivers/gpu/drm/i915/selftests/../i915_drv.h:3546:16: warning: expression using sizeof(void)
+drivers/gpu/drm/i915/selftests/../i915_drv.h:3541:16: warning: expression using sizeof(void)

Commit: drm/i915/selftests: Trim struct_mutex duration for set-wedged selftest
Okay!

Commit: drm/i915: Issue engine resets onto idle engines
Okay!

Commit: drm/i915: Stop tracking MRU activity on VMA
Okay!

Commit: drm/i915: Pull VM lists under the VM mutex.
Okay!

Commit: drm/i915: Move vma lookup to its own lock
Okay!

Commit: drm/i915: Use b->irq_enable() as predicate for mock engine
Okay!

Commit: drm/i915/selftests: Allocate mock ring/timeline per context
Okay!

Commit: drm/i915/selftests: Make evict tolerant of foreign objects
Okay!

Commit: drm/i915: Always allocate an object/vma for the HWSP
Okay!

Commit: drm/i915: Move list of timelines under its own lock
-drivers/gpu/drm/i915/selftests/../i915_drv.h:3541:16: warning: expression using sizeof(void)
+drivers/gpu/drm/i915/selftests/../i915_drv.h:3544:16: warning: expression using sizeof(void)

Commit: drm/i915: Introduce concept of per-timeline (context) HWSP
Okay!

Commit: drm/i915: Enlarge vma->pin_count
Okay!

Commit: drm/i915: Allocate a status page for each timeline
+./include/linux/mm.h:619:13: error: not a function <noident>
+./include/linux/mm.h:619:13: error: undefined identifier '__builtin_mul_overflow'
+./include/linux/mm.h:619:13: warning: call with no type!

Commit: drm/i915: Share per-timeline HWSP using a slab suballocator
-drivers/gpu/drm/i915/selftests/../i915_drv.h:3544:16: warning: expression using sizeof(void)
+drivers/gpu/drm/i915/selftests/../i915_drv.h:3549:16: warning: expression using sizeof(void)

Commit: drm/i915: Keep all partially allocated HWSP on a freelist
-drivers/gpu/drm/i915/selftests/../i915_drv.h:3549:16: warning: expression using sizeof(void)
+drivers/gpu/drm/i915/selftests/../i915_drv.h:3548:16: warning: expression using sizeof(void)

Commit: drm/i915: Track the context's seqno in its own timeline HWSP
Okay!

Commit: drm/i915: Identify active requests
Okay!

Commit: drm/i915: Remove the intel_engine_notify tracepoint
Okay!

Commit: drm/i915: Replace global breadcrumbs with per-context interrupt tracking
+drivers/gpu/drm/i915/selftests/i915_request.c:283:40: warning: expression using sizeof(void)
+drivers/gpu/drm/i915/selftests/i915_request.c:283:40: warning: expression using sizeof(void)
-./include/linux/mm.h:619:13: error: not a function <noident>
-./include/linux/mm.h:619:13: error: not a function <noident>
-./include/linux/mm.h:619:13: error: undefined identifier '__builtin_mul_overflow'
-./include/linux/mm.h:619:13: warning: call with no type!
+./include/linux/slab.h:664:13: error: not a function <noident>
+./include/linux/slab.h:664:13: error: not a function <noident>

Commit: drm/i915: Drop fake breadcrumb irq
Okay!

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https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* ✓ Fi.CI.BAT: success for series starting with [01/23] drm/i915: Make all GPU resets atomic
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (25 preceding siblings ...)
  2019-01-17 15:05 ` ✗ Fi.CI.SPARSE: " Patchwork
@ 2019-01-17 15:38 ` Patchwork
  2019-01-17 23:36 ` ✗ Fi.CI.IGT: failure " Patchwork
  27 siblings, 0 replies; 50+ messages in thread
From: Patchwork @ 2019-01-17 15:38 UTC (permalink / raw)
  To: Chris Wilson; +Cc: intel-gfx

== Series Details ==

Series: series starting with [01/23] drm/i915: Make all GPU resets atomic
URL   : https://patchwork.freedesktop.org/series/55365/
State : success

== Summary ==

CI Bug Log - changes from CI_DRM_5440 -> Patchwork_11970
====================================================

Summary
-------

  **SUCCESS**

  No regressions found.

  External URL: https://patchwork.freedesktop.org/api/1.0/series/55365/revisions/1/mbox/

Known issues
------------

  Here are the changes found in Patchwork_11970 that come from known issues:

### IGT changes ###

#### Issues hit ####

  * igt@i915_selftest@live_execlists:
    - fi-apl-guc:         PASS -> INCOMPLETE [fdo#103927]

  * igt@kms_pipe_crc_basic@nonblocking-crc-pipe-a-frame-sequence:
    - fi-byt-clapper:     NOTRUN -> FAIL [fdo#103191] / [fdo#107362]

  
#### Possible fixes ####

  * igt@kms_frontbuffer_tracking@basic:
    - fi-icl-u3:          FAIL [fdo#103167] -> PASS

  
  {name}: This element is suppressed. This means it is ignored when computing
          the status of the difference (SUCCESS, WARNING, or FAILURE).

  [fdo#103167]: https://bugs.freedesktop.org/show_bug.cgi?id=103167
  [fdo#103191]: https://bugs.freedesktop.org/show_bug.cgi?id=103191
  [fdo#103927]: https://bugs.freedesktop.org/show_bug.cgi?id=103927
  [fdo#107362]: https://bugs.freedesktop.org/show_bug.cgi?id=107362
  [fdo#108622]: https://bugs.freedesktop.org/show_bug.cgi?id=108622
  [fdo#109271]: https://bugs.freedesktop.org/show_bug.cgi?id=109271
  [fdo#109278]: https://bugs.freedesktop.org/show_bug.cgi?id=109278


Participating hosts (45 -> 39)
------------------------------

  Additional (3): fi-kbl-7567u fi-glk-j4005 fi-byt-clapper 
  Missing    (9): fi-kbl-soraka fi-ilk-m540 fi-byt-squawks fi-bsw-cyan fi-kbl-7500u fi-gdg-551 fi-pnv-d510 fi-icl-y fi-snb-2600 


Build changes
-------------

    * Linux: CI_DRM_5440 -> Patchwork_11970

  CI_DRM_5440: b36a89b5ab74fd49a4369e6df0d2c02bc464a474 @ git://anongit.freedesktop.org/gfx-ci/linux
  IGT_4777: 8614d5eb114a660c3bd7ff77eab8bed53424cd30 @ git://anongit.freedesktop.org/xorg/app/intel-gpu-tools
  Patchwork_11970: f7e648e4bba87e1ddbeb45b377ec4470562fb286 @ git://anongit.freedesktop.org/gfx-ci/linux


== Linux commits ==

f7e648e4bba8 drm/i915: Drop fake breadcrumb irq
2c07c68932af drm/i915: Replace global breadcrumbs with per-context interrupt tracking
f4d10d8a497c drm/i915: Remove the intel_engine_notify tracepoint
22e584a722b8 drm/i915: Identify active requests
97e2101df0fe drm/i915: Track the context's seqno in its own timeline HWSP
590309e71727 drm/i915: Keep all partially allocated HWSP on a freelist
9a2c0d841b87 drm/i915: Share per-timeline HWSP using a slab suballocator
90c17ef7381e drm/i915: Allocate a status page for each timeline
722338216230 drm/i915: Enlarge vma->pin_count
fb705705e39d drm/i915: Introduce concept of per-timeline (context) HWSP
4faf687777c5 drm/i915: Move list of timelines under its own lock
a9fb042af3e7 drm/i915: Always allocate an object/vma for the HWSP
e64538758ef8 drm/i915/selftests: Make evict tolerant of foreign objects
a6cd7e980da3 drm/i915/selftests: Allocate mock ring/timeline per context
178df8680efe drm/i915: Use b->irq_enable() as predicate for mock engine
1b8241711cd3 drm/i915: Move vma lookup to its own lock
b590cd93b877 drm/i915: Pull VM lists under the VM mutex.
941079fbcd79 drm/i915: Stop tracking MRU activity on VMA
9c242ce79a77 drm/i915: Issue engine resets onto idle engines
b126705eb583 drm/i915/selftests: Trim struct_mutex duration for set-wedged selftest
13c95ff25011 drm/i915: Remove GPU reset dependence on struct_mutex
84c5d840f63e drm/i915/guc: Disable global reset
cc34d0c113bf drm/i915: Make all GPU resets atomic

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_11970/
_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 08/23] drm/i915: Move vma lookup to its own lock
  2019-01-17 14:34 ` [PATCH 08/23] drm/i915: Move vma lookup to its own lock Chris Wilson
@ 2019-01-17 16:27   ` Tvrtko Ursulin
  2019-01-17 16:31     ` Chris Wilson
  2019-01-17 16:44     ` Chris Wilson
  0 siblings, 2 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-17 16:27 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> Remove the struct_mutex requirement for looking up the vma for an
> object.

Another patch with missing change log.

I see that you at least fixed the tree typo since the round I last 
reviewed. But I also had some other questions which I did not see you 
commented on.

Anyways, it is very hard to review without change logs.. I am not sure 
why is this series particularly bad in this respect.

Regards,

Tvrtko

> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_debugfs.c       |  6 +--
>   drivers/gpu/drm/i915/i915_gem.c           | 33 +++++++------
>   drivers/gpu/drm/i915/i915_gem_object.h    | 45 ++++++++++-------
>   drivers/gpu/drm/i915/i915_vma.c           | 60 +++++++++++++++--------
>   drivers/gpu/drm/i915/i915_vma.h           |  2 +-
>   drivers/gpu/drm/i915/selftests/i915_vma.c |  4 +-
>   6 files changed, 92 insertions(+), 58 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
> index ba7f05b493ed..d052329c2319 100644
> --- a/drivers/gpu/drm/i915/i915_debugfs.c
> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> @@ -159,14 +159,14 @@ describe_obj(struct seq_file *m, struct drm_i915_gem_object *obj)
>   		   obj->mm.madv == I915_MADV_DONTNEED ? " purgeable" : "");
>   	if (obj->base.name)
>   		seq_printf(m, " (name: %d)", obj->base.name);
> -	list_for_each_entry(vma, &obj->vma_list, obj_link) {
> +	list_for_each_entry(vma, &obj->vma.list, obj_link) {
>   		if (i915_vma_is_pinned(vma))
>   			pin_count++;
>   	}
>   	seq_printf(m, " (pinned x %d)", pin_count);
>   	if (obj->pin_global)
>   		seq_printf(m, " (global)");
> -	list_for_each_entry(vma, &obj->vma_list, obj_link) {
> +	list_for_each_entry(vma, &obj->vma.list, obj_link) {
>   		if (!drm_mm_node_allocated(&vma->node))
>   			continue;
>   
> @@ -322,7 +322,7 @@ static int per_file_stats(int id, void *ptr, void *data)
>   	if (obj->base.name || obj->base.dma_buf)
>   		stats->shared += obj->base.size;
>   
> -	list_for_each_entry(vma, &obj->vma_list, obj_link) {
> +	list_for_each_entry(vma, &obj->vma.list, obj_link) {
>   		if (!drm_mm_node_allocated(&vma->node))
>   			continue;
>   
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 538fa5404603..15acd052da46 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -437,15 +437,19 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj)
>   	if (ret)
>   		return ret;
>   
> -	while ((vma = list_first_entry_or_null(&obj->vma_list,
> -					       struct i915_vma,
> -					       obj_link))) {
> +	spin_lock(&obj->vma.lock);
> +	while (!ret && (vma = list_first_entry_or_null(&obj->vma.list,
> +						       struct i915_vma,
> +						       obj_link))) {
>   		list_move_tail(&vma->obj_link, &still_in_list);
> +		spin_unlock(&obj->vma.lock);
> +
>   		ret = i915_vma_unbind(vma);
> -		if (ret)
> -			break;
> +
> +		spin_lock(&obj->vma.lock);
>   	}
> -	list_splice(&still_in_list, &obj->vma_list);
> +	list_splice(&still_in_list, &obj->vma.list);
> +	spin_unlock(&obj->vma.lock);
>   
>   	return ret;
>   }
> @@ -3489,7 +3493,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
>   	 * reading an invalid PTE on older architectures.
>   	 */
>   restart:
> -	list_for_each_entry(vma, &obj->vma_list, obj_link) {
> +	list_for_each_entry(vma, &obj->vma.list, obj_link) {
>   		if (!drm_mm_node_allocated(&vma->node))
>   			continue;
>   
> @@ -3567,7 +3571,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
>   			 */
>   		}
>   
> -		list_for_each_entry(vma, &obj->vma_list, obj_link) {
> +		list_for_each_entry(vma, &obj->vma.list, obj_link) {
>   			if (!drm_mm_node_allocated(&vma->node))
>   				continue;
>   
> @@ -3577,7 +3581,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
>   		}
>   	}
>   
> -	list_for_each_entry(vma, &obj->vma_list, obj_link)
> +	list_for_each_entry(vma, &obj->vma.list, obj_link)
>   		vma->node.color = cache_level;
>   	i915_gem_object_set_cache_coherency(obj, cache_level);
>   	obj->cache_dirty = true; /* Always invalidate stale cachelines */
> @@ -4153,7 +4157,9 @@ void i915_gem_object_init(struct drm_i915_gem_object *obj,
>   {
>   	mutex_init(&obj->mm.lock);
>   
> -	INIT_LIST_HEAD(&obj->vma_list);
> +	spin_lock_init(&obj->vma.lock);
> +	INIT_LIST_HEAD(&obj->vma.list);
> +
>   	INIT_LIST_HEAD(&obj->lut_list);
>   	INIT_LIST_HEAD(&obj->batch_pool_link);
>   
> @@ -4319,14 +4325,13 @@ static void __i915_gem_free_objects(struct drm_i915_private *i915,
>   		mutex_lock(&i915->drm.struct_mutex);
>   
>   		GEM_BUG_ON(i915_gem_object_is_active(obj));
> -		list_for_each_entry_safe(vma, vn,
> -					 &obj->vma_list, obj_link) {
> +		list_for_each_entry_safe(vma, vn, &obj->vma.list, obj_link) {
>   			GEM_BUG_ON(i915_vma_is_active(vma));
>   			vma->flags &= ~I915_VMA_PIN_MASK;
>   			i915_vma_destroy(vma);
>   		}
> -		GEM_BUG_ON(!list_empty(&obj->vma_list));
> -		GEM_BUG_ON(!RB_EMPTY_ROOT(&obj->vma_tree));
> +		GEM_BUG_ON(!list_empty(&obj->vma.list));
> +		GEM_BUG_ON(!RB_EMPTY_ROOT(&obj->vma.tree));
>   
>   		/* This serializes freeing with the shrinker. Since the free
>   		 * is delayed, first by RCU then by the workqueue, we want the
> diff --git a/drivers/gpu/drm/i915/i915_gem_object.h b/drivers/gpu/drm/i915/i915_gem_object.h
> index cb1b0144d274..5a33b6d9f942 100644
> --- a/drivers/gpu/drm/i915/i915_gem_object.h
> +++ b/drivers/gpu/drm/i915/i915_gem_object.h
> @@ -87,24 +87,33 @@ struct drm_i915_gem_object {
>   
>   	const struct drm_i915_gem_object_ops *ops;
>   
> -	/**
> -	 * @vma_list: List of VMAs backed by this object
> -	 *
> -	 * The VMA on this list are ordered by type, all GGTT vma are placed
> -	 * at the head and all ppGTT vma are placed at the tail. The different
> -	 * types of GGTT vma are unordered between themselves, use the
> -	 * @vma_tree (which has a defined order between all VMA) to find an
> -	 * exact match.
> -	 */
> -	struct list_head vma_list;
> -	/**
> -	 * @vma_tree: Ordered tree of VMAs backed by this object
> -	 *
> -	 * All VMA created for this object are placed in the @vma_tree for
> -	 * fast retrieval via a binary search in i915_vma_instance().
> -	 * They are also added to @vma_list for easy iteration.
> -	 */
> -	struct rb_root vma_tree;
> +	struct {
> +		/**
> +		 * @vma.lock: protect the list/tree of vmas
> +		 */
> +		struct spinlock lock;
> +
> +		/**
> +		 * @vma.list: List of VMAs backed by this object
> +		 *
> +		 * The VMA on this list are ordered by type, all GGTT vma are
> +		 * placed at the head and all ppGTT vma are placed at the tail.
> +		 * The different types of GGTT vma are unordered between
> +		 * themselves, use the @vma.tree (which has a defined order
> +		 * between all VMA) to quickly find an exact match.
> +		 */
> +		struct list_head list;
> +
> +		/**
> +		 * @vma.tree: Ordered tree of VMAs backed by this object
> +		 *
> +		 * All VMA created for this object are placed in the @vma.tree
> +		 * for fast retrieval via a binary search in
> +		 * i915_vma_instance(). They are also added to @vma.list for
> +		 * easy iteration.
> +		 */
> +		struct rb_root tree;
> +	} vma;
>   
>   	/**
>   	 * @lut_list: List of vma lookup entries in use for this object.
> diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
> index dcbd0d345c72..3a680fe2bb8b 100644
> --- a/drivers/gpu/drm/i915/i915_vma.c
> +++ b/drivers/gpu/drm/i915/i915_vma.c
> @@ -187,32 +187,47 @@ vma_create(struct drm_i915_gem_object *obj,
>   								i915_gem_object_get_stride(obj));
>   		GEM_BUG_ON(!is_power_of_2(vma->fence_alignment));
>   
> -		/*
> -		 * We put the GGTT vma at the start of the vma-list, followed
> -		 * by the ppGGTT vma. This allows us to break early when
> -		 * iterating over only the GGTT vma for an object, see
> -		 * for_each_ggtt_vma()
> -		 */
>   		vma->flags |= I915_VMA_GGTT;
> -		list_add(&vma->obj_link, &obj->vma_list);
> -	} else {
> -		list_add_tail(&vma->obj_link, &obj->vma_list);
>   	}
>   
> +	spin_lock(&obj->vma.lock);
> +
>   	rb = NULL;
> -	p = &obj->vma_tree.rb_node;
> +	p = &obj->vma.tree.rb_node;
>   	while (*p) {
>   		struct i915_vma *pos;
> +		long cmp;
>   
>   		rb = *p;
>   		pos = rb_entry(rb, struct i915_vma, obj_node);
> -		if (i915_vma_compare(pos, vm, view) < 0)
> +
> +		cmp = i915_vma_compare(pos, vm, view);
> +		if (cmp == 0) {
> +			spin_unlock(&obj->vma.lock);
> +			kmem_cache_free(vm->i915->vmas, vma);
> +			return pos;
> +		}
> +
> +		if (cmp < 0)
>   			p = &rb->rb_right;
>   		else
>   			p = &rb->rb_left;
>   	}
>   	rb_link_node(&vma->obj_node, rb, p);
> -	rb_insert_color(&vma->obj_node, &obj->vma_tree);
> +	rb_insert_color(&vma->obj_node, &obj->vma.tree);
> +
> +	if (i915_vma_is_ggtt(vma))
> +		/*
> +		 * We put the GGTT vma at the start of the vma-list, followed
> +		 * by the ppGGTT vma. This allows us to break early when
> +		 * iterating over only the GGTT vma for an object, see
> +		 * for_each_ggtt_vma()
> +		 */
> +		list_add(&vma->obj_link, &obj->vma.list);
> +	else
> +		list_add_tail(&vma->obj_link, &obj->vma.list);
> +
> +	spin_unlock(&obj->vma.lock);
>   
>   	mutex_lock(&vm->mutex);
>   	list_add(&vma->vm_link, &vm->unbound_list);
> @@ -232,7 +247,7 @@ vma_lookup(struct drm_i915_gem_object *obj,
>   {
>   	struct rb_node *rb;
>   
> -	rb = obj->vma_tree.rb_node;
> +	rb = obj->vma.tree.rb_node;
>   	while (rb) {
>   		struct i915_vma *vma = rb_entry(rb, struct i915_vma, obj_node);
>   		long cmp;
> @@ -272,16 +287,17 @@ i915_vma_instance(struct drm_i915_gem_object *obj,
>   {
>   	struct i915_vma *vma;
>   
> -	lockdep_assert_held(&obj->base.dev->struct_mutex);
>   	GEM_BUG_ON(view && !i915_is_ggtt(vm));
>   	GEM_BUG_ON(vm->closed);
>   
> +	spin_lock(&obj->vma.lock);
>   	vma = vma_lookup(obj, vm, view);
> -	if (!vma)
> +	spin_unlock(&obj->vma.lock);
> +
> +	if (unlikely(!vma))
>   		vma = vma_create(obj, vm, view);
>   
>   	GEM_BUG_ON(!IS_ERR(vma) && i915_vma_compare(vma, vm, view));
> -	GEM_BUG_ON(!IS_ERR(vma) && vma_lookup(obj, vm, view) != vma);
>   	return vma;
>   }
>   
> @@ -808,14 +824,18 @@ static void __i915_vma_destroy(struct i915_vma *vma)
>   
>   	GEM_BUG_ON(i915_gem_active_isset(&vma->last_fence));
>   
> -	list_del(&vma->obj_link);
> -
>   	mutex_lock(&vma->vm->mutex);
>   	list_del(&vma->vm_link);
>   	mutex_unlock(&vma->vm->mutex);
>   
> -	if (vma->obj)
> -		rb_erase(&vma->obj_node, &vma->obj->vma_tree);
> +	if (vma->obj) {
> +		struct drm_i915_gem_object *obj = vma->obj;
> +
> +		spin_lock(&obj->vma.lock);
> +		list_del(&vma->obj_link);
> +		rb_erase(&vma->obj_node, &vma->obj->vma.tree);
> +		spin_unlock(&obj->vma.lock);
> +	}
>   
>   	rbtree_postorder_for_each_entry_safe(iter, n, &vma->active, node) {
>   		GEM_BUG_ON(i915_gem_active_isset(&iter->base));
> diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
> index 4f7c1c7599f4..7252abc73d3e 100644
> --- a/drivers/gpu/drm/i915/i915_vma.h
> +++ b/drivers/gpu/drm/i915/i915_vma.h
> @@ -425,7 +425,7 @@ void i915_vma_parked(struct drm_i915_private *i915);
>    * or the list is empty ofc.
>    */
>   #define for_each_ggtt_vma(V, OBJ) \
> -	list_for_each_entry(V, &(OBJ)->vma_list, obj_link)		\
> +	list_for_each_entry(V, &(OBJ)->vma.list, obj_link)		\
>   		for_each_until(!i915_vma_is_ggtt(V))
>   
>   #endif
> diff --git a/drivers/gpu/drm/i915/selftests/i915_vma.c b/drivers/gpu/drm/i915/selftests/i915_vma.c
> index ffa74290e054..f1008b07dfd2 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_vma.c
> +++ b/drivers/gpu/drm/i915/selftests/i915_vma.c
> @@ -670,7 +670,7 @@ static int igt_vma_partial(void *arg)
>   		}
>   
>   		count = 0;
> -		list_for_each_entry(vma, &obj->vma_list, obj_link)
> +		list_for_each_entry(vma, &obj->vma.list, obj_link)
>   			count++;
>   		if (count != nvma) {
>   			pr_err("(%s) All partial vma were not recorded on the obj->vma_list: found %u, expected %u\n",
> @@ -699,7 +699,7 @@ static int igt_vma_partial(void *arg)
>   		i915_vma_unpin(vma);
>   
>   		count = 0;
> -		list_for_each_entry(vma, &obj->vma_list, obj_link)
> +		list_for_each_entry(vma, &obj->vma.list, obj_link)
>   			count++;
>   		if (count != nvma) {
>   			pr_err("(%s) allocated an extra full vma!\n", p->name);
> 
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 08/23] drm/i915: Move vma lookup to its own lock
  2019-01-17 16:27   ` Tvrtko Ursulin
@ 2019-01-17 16:31     ` Chris Wilson
  2019-01-17 16:36       ` Chris Wilson
  2019-01-17 16:44     ` Chris Wilson
  1 sibling, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 16:31 UTC (permalink / raw)
  To: Tvrtko Ursulin, intel-gfx

Quoting Tvrtko Ursulin (2019-01-17 16:27:04)
> 
> On 17/01/2019 14:34, Chris Wilson wrote:
> > Remove the struct_mutex requirement for looking up the vma for an
> > object.
> 
> Another patch with missing change log.

There was no functional change.

> I see that you at least fixed the tree typo since the round I last 
> reviewed. But I also had some other questions which I did not see you 
> commented on.

I answer those questions.
-Chris
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 08/23] drm/i915: Move vma lookup to its own lock
  2019-01-17 16:31     ` Chris Wilson
@ 2019-01-17 16:36       ` Chris Wilson
  2019-01-17 16:51         ` Tvrtko Ursulin
  0 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 16:36 UTC (permalink / raw)
  To: Tvrtko Ursulin, intel-gfx

Quoting Chris Wilson (2019-01-17 16:31:27)
> Quoting Tvrtko Ursulin (2019-01-17 16:27:04)
> > 
> > On 17/01/2019 14:34, Chris Wilson wrote:
> > > Remove the struct_mutex requirement for looking up the vma for an
> > > object.
> > 
> > Another patch with missing change log.
> 
> There was no functional change.
> 
> > I see that you at least fixed the tree typo since the round I last 
> > reviewed. But I also had some other questions which I did not see you 
> > commented on.
> 
> I answer those questions.
in 154644420773.27300.5770992084643848631@skylake-alporthouse-com
?
-Chris
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 08/23] drm/i915: Move vma lookup to its own lock
  2019-01-17 16:27   ` Tvrtko Ursulin
  2019-01-17 16:31     ` Chris Wilson
@ 2019-01-17 16:44     ` Chris Wilson
  1 sibling, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 16:44 UTC (permalink / raw)
  To: Tvrtko Ursulin, intel-gfx

Quoting Tvrtko Ursulin (2019-01-17 16:27:04)
> 
> On 17/01/2019 14:34, Chris Wilson wrote:
> > Remove the struct_mutex requirement for looking up the vma for an
> > object.
> 
> Another patch with missing change log.
> 
> I see that you at least fixed the tree typo since the round I last 
> reviewed. But I also had some other questions which I did not see you 
> commented on.
> 
> Anyways, it is very hard to review without change logs.. I am not sure 
> why is this series particularly bad in this respect.

The short explanation, as given on the next patch,

                rb = *p;
                pos = rb_entry(rb, struct i915_vma, obj_node);

+               /*
+                * If the view already exists in the tree, another thread
+                * already created a matching vma, so return the older instance
+                * and dispose of ours.
+                */
                cmp = i915_vma_compare(pos, vm, view);
                if (cmp == 0) {
                        spin_unlock(&obj->vma.lock);
@@ -294,6 +299,7 @@ i915_vma_instance(struct drm_i915_gem_object *obj,
        vma = vma_lookup(obj, vm, view);
        spin_unlock(&obj->vma.lock);

+       /* vma_create() will resolve the race if another creates the vma */
        if (unlikely(!vma))
                vma = vma_create(obj, vm, view);

which should explain why the whitespace is peculiar and the early return
returns pos not vma.
-Chris
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 09/23] drm/i915: Use b->irq_enable() as predicate for mock engine
  2019-01-17 14:34 ` [PATCH 09/23] drm/i915: Use b->irq_enable() as predicate for mock engine Chris Wilson
@ 2019-01-17 16:44   ` Tvrtko Ursulin
  2019-01-17 16:52     ` Chris Wilson
  0 siblings, 1 reply; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-17 16:44 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> Since commit  d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")
> we have required a mechanism to avoid touching the interrupt hardware
> for breadcrumbs, superseding our mock interface for selftests.
> 
> References: d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/intel_breadcrumbs.c     | 39 ++++++++------------
>   drivers/gpu/drm/i915/intel_engine_cs.c       | 11 ++----
>   drivers/gpu/drm/i915/intel_ringbuffer.h      |  1 -
>   drivers/gpu/drm/i915/selftests/mock_engine.c |  1 -
>   4 files changed, 20 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c
> index 4ed7105d7ff5..7b517bf83507 100644
> --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c
> +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
> @@ -158,6 +158,9 @@ static void intel_breadcrumbs_fake_irq(struct timer_list *t)
>   
>   static void irq_enable(struct intel_engine_cs *engine)
>   {
> +	if (!engine->irq_enable)
> +		return;
> +
>   	/*
>   	 * FIXME: Ideally we want this on the API boundary, but for the
>   	 * sake of testing with mock breadcrumbs (no HW so unable to

Okay I think I misunderstood this patch in the last round. So you want 
to avoid the GEM_BUG_ON below _and_ a dedicated boolean only for the 
mock engine.

I only wonder on the remaining merit of this comment and actually a 
GEM_BUG_ON, which will be hit and miss depending on the platform now. 
Gut feeling says something is still not ideal here. Selftests variable 
does actually feel better in this sense.

mock_engine seems only used from mock_gem_device, so could an 
alternative be to set i915->runtime_pm.irqs_enabled there and keep the 
GEM_BUG_ON in irq_enable above the !engine->irq_enable early return? 
That would still provide the unconditional assert on the state of the 
driver outside selftests.

Regards,

Tvrtko

> @@ -167,21 +170,20 @@ static void irq_enable(struct intel_engine_cs *engine)
>   	GEM_BUG_ON(!intel_irqs_enabled(engine->i915));
>   
>   	/* Caller disables interrupts */
> -	if (engine->irq_enable) {
> -		spin_lock(&engine->i915->irq_lock);
> -		engine->irq_enable(engine);
> -		spin_unlock(&engine->i915->irq_lock);
> -	}
> +	spin_lock(&engine->i915->irq_lock);
> +	engine->irq_enable(engine);
> +	spin_unlock(&engine->i915->irq_lock);
>   }
>   
>   static void irq_disable(struct intel_engine_cs *engine)
>   {
> +	if (!engine->irq_disable)
> +		return;
> +
>   	/* Caller disables interrupts */
> -	if (engine->irq_disable) {
> -		spin_lock(&engine->i915->irq_lock);
> -		engine->irq_disable(engine);
> -		spin_unlock(&engine->i915->irq_lock);
> -	}
> +	spin_lock(&engine->i915->irq_lock);
> +	engine->irq_disable(engine);
> +	spin_unlock(&engine->i915->irq_lock);
>   }
>   
>   void __intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine)
> @@ -293,25 +295,16 @@ static bool __intel_breadcrumbs_enable_irq(struct intel_breadcrumbs *b)
>   	if (b->irq_armed)
>   		return false;
>   
> -	/* The breadcrumb irq will be disarmed on the interrupt after the
> +	/*
> +	 * The breadcrumb irq will be disarmed on the interrupt after the
>   	 * waiters are signaled. This gives us a single interrupt window in
>   	 * which we can add a new waiter and avoid the cost of re-enabling
>   	 * the irq.
>   	 */
>   	b->irq_armed = true;
>   
> -	if (I915_SELFTEST_ONLY(b->mock)) {
> -		/* For our mock objects we want to avoid interaction
> -		 * with the real hardware (which is not set up). So
> -		 * we simply pretend we have enabled the powerwell
> -		 * and the irq, and leave it up to the mock
> -		 * implementation to call intel_engine_wakeup()
> -		 * itself when it wants to simulate a user interrupt,
> -		 */
> -		return true;
> -	}
> -
> -	/* Since we are waiting on a request, the GPU should be busy
> +	/*
> +	 * Since we are waiting on a request, the GPU should be busy
>   	 * and should have its own rpm reference. This is tracked
>   	 * by i915->gt.awake, we can forgo holding our own wakref
>   	 * for the interrupt as before i915->gt.awake is released (when
> diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
> index e2f65c59d6e8..fc52737751e7 100644
> --- a/drivers/gpu/drm/i915/intel_engine_cs.c
> +++ b/drivers/gpu/drm/i915/intel_engine_cs.c
> @@ -917,6 +917,9 @@ static bool ring_is_idle(struct intel_engine_cs *engine)
>   	intel_wakeref_t wakeref;
>   	bool idle = true;
>   
> +	if (I915_SELFTEST_ONLY(!engine->mmio_base))
> +		return true;
> +
>   	/* If the whole device is asleep, the engine must be idle */
>   	wakeref = intel_runtime_pm_get_if_in_use(dev_priv);
>   	if (!wakeref)
> @@ -955,9 +958,6 @@ bool intel_engine_is_idle(struct intel_engine_cs *engine)
>   	if (!intel_engine_signaled(engine, intel_engine_last_submit(engine)))
>   		return false;
>   
> -	if (I915_SELFTEST_ONLY(engine->breadcrumbs.mock))
> -		return true;
> -
>   	/* Waiting to drain ELSP? */
>   	if (READ_ONCE(engine->execlists.active)) {
>   		struct tasklet_struct *t = &engine->execlists.tasklet;
> @@ -983,10 +983,7 @@ bool intel_engine_is_idle(struct intel_engine_cs *engine)
>   		return false;
>   
>   	/* Ring stopped? */
> -	if (!ring_is_idle(engine))
> -		return false;
> -
> -	return true;
> +	return ring_is_idle(engine);
>   }
>   
>   bool intel_engines_are_idle(struct drm_i915_private *dev_priv)
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
> index 1adf9845710c..17e05d11ee34 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.h
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
> @@ -397,7 +397,6 @@ struct intel_engine_cs {
>   		unsigned int irq_count;
>   
>   		bool irq_armed : 1;
> -		I915_SELFTEST_DECLARE(bool mock : 1);
>   	} breadcrumbs;
>   
>   	struct {
> diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
> index 50e1a0b1af7e..9fe5b2c8f8d4 100644
> --- a/drivers/gpu/drm/i915/selftests/mock_engine.c
> +++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
> @@ -201,7 +201,6 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
>   	i915_timeline_set_subclass(&engine->base.timeline, TIMELINE_ENGINE);
>   
>   	intel_engine_init_breadcrumbs(&engine->base);
> -	engine->base.breadcrumbs.mock = true; /* prevent touching HW for irqs */
>   
>   	/* fake hw queue */
>   	spin_lock_init(&engine->hw_lock);
> 
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 08/23] drm/i915: Move vma lookup to its own lock
  2019-01-17 16:36       ` Chris Wilson
@ 2019-01-17 16:51         ` Tvrtko Ursulin
  0 siblings, 0 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-17 16:51 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 16:36, Chris Wilson wrote:
> Quoting Chris Wilson (2019-01-17 16:31:27)
>> Quoting Tvrtko Ursulin (2019-01-17 16:27:04)
>>>
>>> On 17/01/2019 14:34, Chris Wilson wrote:
>>>> Remove the struct_mutex requirement for looking up the vma for an
>>>> object.
>>>
>>> Another patch with missing change log.
>>
>> There was no functional change.
>>
>>> I see that you at least fixed the tree typo since the round I last
>>> reviewed. But I also had some other questions which I did not see you
>>> commented on.
>>
>> I answer those questions.
> in 154644420773.27300.5770992084643848631@skylake-alporthouse-com
> ?

Hm.. no hits for me anywhere. Can you see it in the archives?

Regards,

Tvrtko

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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 09/23] drm/i915: Use b->irq_enable() as predicate for mock engine
  2019-01-17 16:44   ` Tvrtko Ursulin
@ 2019-01-17 16:52     ` Chris Wilson
  2019-01-17 18:00       ` Tvrtko Ursulin
  0 siblings, 1 reply; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 16:52 UTC (permalink / raw)
  To: Tvrtko Ursulin, intel-gfx

Quoting Tvrtko Ursulin (2019-01-17 16:44:54)
> 
> On 17/01/2019 14:34, Chris Wilson wrote:
> > Since commit  d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")
> > we have required a mechanism to avoid touching the interrupt hardware
> > for breadcrumbs, superseding our mock interface for selftests.
> > 
> > References: d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")
> > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > ---
> >   drivers/gpu/drm/i915/intel_breadcrumbs.c     | 39 ++++++++------------
> >   drivers/gpu/drm/i915/intel_engine_cs.c       | 11 ++----
> >   drivers/gpu/drm/i915/intel_ringbuffer.h      |  1 -
> >   drivers/gpu/drm/i915/selftests/mock_engine.c |  1 -
> >   4 files changed, 20 insertions(+), 32 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c
> > index 4ed7105d7ff5..7b517bf83507 100644
> > --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c
> > +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
> > @@ -158,6 +158,9 @@ static void intel_breadcrumbs_fake_irq(struct timer_list *t)
> >   
> >   static void irq_enable(struct intel_engine_cs *engine)
> >   {
> > +     if (!engine->irq_enable)
> > +             return;
> > +
> >       /*
> >        * FIXME: Ideally we want this on the API boundary, but for the
> >        * sake of testing with mock breadcrumbs (no HW so unable to
> 
> Okay I think I misunderstood this patch in the last round. So you want 
> to avoid the GEM_BUG_ON below _and_ a dedicated boolean only for the 
> mock engine.
> 
> I only wonder on the remaining merit of this comment and actually a 
> GEM_BUG_ON, which will be hit and miss depending on the platform now. 
> Gut feeling says something is still not ideal here. Selftests variable 
> does actually feel better in this sense.
> 
> mock_engine seems only used from mock_gem_device, so could an 
> alternative be to set i915->runtime_pm.irqs_enabled there and keep the 
> GEM_BUG_ON in irq_enable above the !engine->irq_enable early return? 
> That would still provide the unconditional assert on the state of the 
> driver outside selftests.

I'm just going to kill the mention of irqs enabled here, eventually. It
was interesting once because we messed up suspend a decade ago and had to
handle the case of waiting after we had already uninstalled the irq
handler.

This is nothing to do with irqs_enabled; the selftest variable was all
because the mock engine had no engine->irq_enable() callback, and now it
is not the only engine so the assumption that we must always have
engine->irq_enable() is invalid.
-Chris
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 11/23] drm/i915/selftests: Make evict tolerant of foreign objects
  2019-01-17 14:34 ` [PATCH 11/23] drm/i915/selftests: Make evict tolerant of foreign objects Chris Wilson
@ 2019-01-17 17:29   ` Tvrtko Ursulin
  2019-01-18 11:23     ` Chris Wilson
  0 siblings, 1 reply; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-17 17:29 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> The evict selftests presumed that all objects in use had been allocated
> by itself. This is a dubious claim and so instead of asserting complete
> control over the object lists, take (temporary) ownership of them
> instead.
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>   .../gpu/drm/i915/selftests/i915_gem_evict.c   | 64 +++++++++++++++----
>   1 file changed, 53 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> index fb7df895afeb..c8deb961a020 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> +++ b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> @@ -31,30 +31,63 @@
>   
>   static int populate_ggtt(struct drm_i915_private *i915)
>   {
> -	struct drm_i915_gem_object *obj;
> +	struct drm_i915_gem_object *obj, *on;
> +	unsigned long expected_unbound, expected_bound;
> +	unsigned long unbound, bound, count;

Minor/optional comment - longs seem like overkill for either filling 
ggtt with page size objects or for initial state. :)

>   	u64 size;
> +	int err;
> +
> +	expected_unbound = 0;
> +	list_for_each_entry(obj, &i915->mm.unbound_list, mm.link) {
> +		i915_gem_object_get(obj);
> +		expected_unbound++;
> +	}
> +
> +	expected_bound = 0;
> +	list_for_each_entry(obj, &i915->mm.bound_list, mm.link) {
> +		i915_gem_object_get(obj);
> +		expected_bound++;
> +	}
>   
> +	count = 0;
>   	for (size = 0;
>   	     size + I915_GTT_PAGE_SIZE <= i915->ggtt.vm.total;
>   	     size += I915_GTT_PAGE_SIZE) {
>   		struct i915_vma *vma;
>   
>   		obj = i915_gem_object_create_internal(i915, I915_GTT_PAGE_SIZE);
> -		if (IS_ERR(obj))
> -			return PTR_ERR(obj);
> +		if (IS_ERR(obj)) {
> +			err = PTR_ERR(obj);
> +			goto cleanup;
> +		}
>   
>   		vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
> -		if (IS_ERR(vma))
> -			return PTR_ERR(vma);
> +		if (IS_ERR(vma)) {
> +			err = PTR_ERR(vma);
> +			goto cleanup;
> +		}
> +
> +		count++;
>   	}
>   
> -	if (!list_empty(&i915->mm.unbound_list)) {
> -		size = 0;
> -		list_for_each_entry(obj, &i915->mm.unbound_list, mm.link)
> -			size++;
> +	unbound = 0;
> +	list_for_each_entry(obj, &i915->mm.unbound_list, mm.link)
> +		unbound++;
> +	if (unbound != expected_unbound) {
> +		pr_err("%s: Found %lu objects unbound, expected %lu!\n",
> +		       __func__, unbound, expected_unbound);
> +		err = -EINVAL;
> +		goto cleanup;
> +	}
>   
> -		pr_err("Found %lld objects unbound!\n", size);
> -		return -EINVAL;
> +	bound = 0;
> +	list_for_each_entry(obj, &i915->mm.bound_list, mm.link)
> +		bound++;
> +	if (bound != expected_bound + count) {
> +		pr_err("%s: Found %lu objects bound, expected %lu!\n",
> +		       __func__, bound, expected_bound + count);
> +		err = -EINVAL;
> +		goto cleanup;
>   	}
>   
>   	if (list_empty(&i915->ggtt.vm.bound_list)) {
> @@ -63,6 +96,15 @@ static int populate_ggtt(struct drm_i915_private *i915)
>   	}
>   
>   	return 0;
> +
> +cleanup:
> +	list_for_each_entry_safe(obj, on, &i915->mm.unbound_list, mm.link)
> +		i915_gem_object_put(obj);
> +
> +	list_for_each_entry_safe(obj, on, &i915->mm.bound_list, mm.link)
> +		i915_gem_object_put(obj);
> +
> +	return err;
>   }
>   
>   static void unpin_ggtt(struct drm_i915_private *i915)
> 

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 13/23] drm/i915: Move list of timelines under its own lock
  2019-01-17 14:34 ` [PATCH 13/23] drm/i915: Move list of timelines under its own lock Chris Wilson
@ 2019-01-17 17:54   ` Tvrtko Ursulin
  2019-01-18 11:31     ` Chris Wilson
  0 siblings, 1 reply; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-17 17:54 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> Currently, the list of timelines is serialised by the struct_mutex, but
> to alleviate difficulties with using that mutex in future, move the
> list management under its own dedicated mutex.
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_drv.h               |  5 +-
>   drivers/gpu/drm/i915/i915_gem.c               | 89 +++++++++----------
>   drivers/gpu/drm/i915/i915_reset.c             |  8 +-
>   drivers/gpu/drm/i915/i915_timeline.c          | 38 ++++++--
>   drivers/gpu/drm/i915/i915_timeline.h          |  3 +
>   drivers/gpu/drm/i915/i915_vma.c               |  6 ++
>   .../gpu/drm/i915/selftests/mock_gem_device.c  |  7 +-
>   .../gpu/drm/i915/selftests/mock_timeline.c    |  3 +-
>   8 files changed, 101 insertions(+), 58 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 94680b15bed0..3913900600b7 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1975,7 +1975,10 @@ struct drm_i915_private {
>   		void (*resume)(struct drm_i915_private *);
>   		void (*cleanup_engine)(struct intel_engine_cs *engine);
>   
> -		struct list_head timelines;
> +		struct i915_gt_timelines {
> +			struct mutex mutex; /* protects list, tainted by GPU */

What does it mean "tainted by GPU"?

> +			struct list_head list;
> +		} timelines;
>   
>   		struct list_head active_rings;
>   		struct list_head closed_vma;
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 15acd052da46..3c6091021290 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -3222,33 +3222,6 @@ i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>   	return ret;
>   }
>   
> -static long wait_for_timeline(struct i915_timeline *tl,
> -			      unsigned int flags, long timeout)
> -{
> -	struct i915_request *rq;
> -
> -	rq = i915_gem_active_get_unlocked(&tl->last_request);
> -	if (!rq)
> -		return timeout;
> -
> -	/*
> -	 * "Race-to-idle".
> -	 *
> -	 * Switching to the kernel context is often used a synchronous
> -	 * step prior to idling, e.g. in suspend for flushing all
> -	 * current operations to memory before sleeping. These we
> -	 * want to complete as quickly as possible to avoid prolonged
> -	 * stalls, so allow the gpu to boost to maximum clocks.
> -	 */
> -	if (flags & I915_WAIT_FOR_IDLE_BOOST)
> -		gen6_rps_boost(rq, NULL);
> -
> -	timeout = i915_request_wait(rq, flags, timeout);
> -	i915_request_put(rq);
> -
> -	return timeout;
> -}
> -
>   static int wait_for_engines(struct drm_i915_private *i915)
>   {
>   	if (wait_for(intel_engines_are_idle(i915), I915_IDLE_ENGINES_TIMEOUT)) {
> @@ -3265,6 +3238,8 @@ static int wait_for_engines(struct drm_i915_private *i915)
>   int i915_gem_wait_for_idle(struct drm_i915_private *i915,
>   			   unsigned int flags, long timeout)
>   {
> +	struct i915_timeline *tl;
> +
>   	GEM_TRACE("flags=%x (%s), timeout=%ld%s\n",
>   		  flags, flags & I915_WAIT_LOCKED ? "locked" : "unlocked",
>   		  timeout, timeout == MAX_SCHEDULE_TIMEOUT ? " (forever)" : "");
> @@ -3273,17 +3248,45 @@ int i915_gem_wait_for_idle(struct drm_i915_private *i915,
>   	if (!READ_ONCE(i915->gt.awake))
>   		return 0;
>   
> +	mutex_lock(&i915->gt.timelines.mutex);
> +	list_for_each_entry(tl, &i915->gt.timelines.list, link) {
> +		struct i915_request *rq;
> +
> +		rq = i915_gem_active_get_unlocked(&tl->last_request);
> +		if (!rq)
> +			continue;
> +
> +		mutex_unlock(&i915->gt.timelines.mutex);
> +
> +		/*
> +		 * "Race-to-idle".
> +		 *
> +		 * Switching to the kernel context is often used a synchronous
> +		 * step prior to idling, e.g. in suspend for flushing all
> +		 * current operations to memory before sleeping. These we
> +		 * want to complete as quickly as possible to avoid prolonged
> +		 * stalls, so allow the gpu to boost to maximum clocks.
> +		 */
> +		if (flags & I915_WAIT_FOR_IDLE_BOOST)
> +			gen6_rps_boost(rq, NULL);
> +
> +		timeout = i915_request_wait(rq, flags, timeout);
> +		i915_request_put(rq);
> +		if (timeout < 0)
> +			return timeout;
> +
> +		mutex_lock(&i915->gt.timelines.mutex);
> +
> +		/* restart after dropping the lock */
> +		tl = list_entry(&i915->gt.timelines.list, typeof(*tl), link);
> +	}
> +	mutex_unlock(&i915->gt.timelines.mutex);

Hm, since the loop above bothers restarting after dropping the lock, 
that implies when we drop the lock here we may not be idle any longer. 
Or we actually still depend on struct_mutex and this is another small 
charade? I guess so, since without this patch we also have two path with 
different levels of idleness guarantee.

> +
>   	if (flags & I915_WAIT_LOCKED) {
> -		struct i915_timeline *tl;
>   		int err;
>   
>   		lockdep_assert_held(&i915->drm.struct_mutex);
>   
> -		list_for_each_entry(tl, &i915->gt.timelines, link) {
> -			timeout = wait_for_timeline(tl, flags, timeout);
> -			if (timeout < 0)
> -				return timeout;
> -		}
>   		if (GEM_SHOW_DEBUG() && !timeout) {
>   			/* Presume that timeout was non-zero to begin with! */
>   			dev_warn(&i915->drm.pdev->dev,
> @@ -3297,17 +3300,6 @@ int i915_gem_wait_for_idle(struct drm_i915_private *i915,
>   
>   		i915_retire_requests(i915);
>   		GEM_BUG_ON(i915->gt.active_requests);
> -	} else {
> -		struct intel_engine_cs *engine;
> -		enum intel_engine_id id;
> -
> -		for_each_engine(engine, i915, id) {
> -			struct i915_timeline *tl = &engine->timeline;
> -
> -			timeout = wait_for_timeline(tl, flags, timeout);
> -			if (timeout < 0)
> -				return timeout;
> -		}
>   	}
>   
>   	return 0;
> @@ -5008,6 +5000,8 @@ int i915_gem_init(struct drm_i915_private *dev_priv)
>   		dev_priv->gt.cleanup_engine = intel_engine_cleanup;
>   	}
>   
> +	i915_timelines_init(dev_priv);
> +
>   	ret = i915_gem_init_userptr(dev_priv);
>   	if (ret)
>   		return ret;
> @@ -5130,8 +5124,10 @@ int i915_gem_init(struct drm_i915_private *dev_priv)
>   err_uc_misc:
>   	intel_uc_fini_misc(dev_priv);
>   
> -	if (ret != -EIO)
> +	if (ret != -EIO) {
>   		i915_gem_cleanup_userptr(dev_priv);
> +		i915_timelines_fini(dev_priv);
> +	}
>   
>   	if (ret == -EIO) {
>   		mutex_lock(&dev_priv->drm.struct_mutex);
> @@ -5182,6 +5178,7 @@ void i915_gem_fini(struct drm_i915_private *dev_priv)
>   
>   	intel_uc_fini_misc(dev_priv);
>   	i915_gem_cleanup_userptr(dev_priv);
> +	i915_timelines_fini(dev_priv);
>   
>   	i915_gem_drain_freed_objects(dev_priv);
>   
> @@ -5284,7 +5281,6 @@ int i915_gem_init_early(struct drm_i915_private *dev_priv)
>   	if (!dev_priv->priorities)
>   		goto err_dependencies;
>   
> -	INIT_LIST_HEAD(&dev_priv->gt.timelines);
>   	INIT_LIST_HEAD(&dev_priv->gt.active_rings);
>   	INIT_LIST_HEAD(&dev_priv->gt.closed_vma);
>   
> @@ -5328,7 +5324,6 @@ void i915_gem_cleanup_early(struct drm_i915_private *dev_priv)
>   	GEM_BUG_ON(!llist_empty(&dev_priv->mm.free_list));
>   	GEM_BUG_ON(atomic_read(&dev_priv->mm.free_count));
>   	WARN_ON(dev_priv->mm.object_count);
> -	WARN_ON(!list_empty(&dev_priv->gt.timelines));
>   
>   	kmem_cache_destroy(dev_priv->priorities);
>   	kmem_cache_destroy(dev_priv->dependencies);
> diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
> index d44b095e2860..12e5a2bc825c 100644
> --- a/drivers/gpu/drm/i915/i915_reset.c
> +++ b/drivers/gpu/drm/i915/i915_reset.c
> @@ -850,7 +850,8 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
>   	 *
>   	 * No more can be submitted until we reset the wedged bit.
>   	 */
> -	list_for_each_entry(tl, &i915->gt.timelines, link) {
> +	mutex_lock(&i915->gt.timelines.mutex);
> +	list_for_each_entry(tl, &i915->gt.timelines.list, link) {
>   		struct i915_request *rq;
>   		long timeout;
>   
> @@ -872,9 +873,12 @@ bool i915_gem_unset_wedged(struct drm_i915_private *i915)
>   		timeout = dma_fence_default_wait(&rq->fence, true,
>   						 MAX_SCHEDULE_TIMEOUT);
>   		i915_request_put(rq);
> -		if (timeout < 0)
> +		if (timeout < 0) {
> +			mutex_unlock(&i915->gt.timelines.mutex);
>   			goto unlock;
> +		}
>   	}
> +	mutex_unlock(&i915->gt.timelines.mutex);
>   
>   	intel_engines_sanitize(i915, false);
>   
> diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
> index 4667cc08c416..84550f17d3df 100644
> --- a/drivers/gpu/drm/i915/i915_timeline.c
> +++ b/drivers/gpu/drm/i915/i915_timeline.c
> @@ -13,7 +13,7 @@ void i915_timeline_init(struct drm_i915_private *i915,
>   			struct i915_timeline *timeline,
>   			const char *name)
>   {
> -	lockdep_assert_held(&i915->drm.struct_mutex);
> +	struct i915_gt_timelines *gt = &i915->gt.timelines;
>   
>   	/*
>   	 * Ideally we want a set of engines on a single leaf as we expect
> @@ -23,9 +23,12 @@ void i915_timeline_init(struct drm_i915_private *i915,
>   	 */
>   	BUILD_BUG_ON(KSYNCMAP < I915_NUM_ENGINES);
>   
> +	timeline->i915 = i915;
>   	timeline->name = name;
>   
> -	list_add(&timeline->link, &i915->gt.timelines);
> +	mutex_lock(&gt->mutex);
> +	list_add(&timeline->link, &gt->list);
> +	mutex_unlock(&gt->mutex);
>   
>   	/* Called during early_init before we know how many engines there are */
>   
> @@ -39,6 +42,17 @@ void i915_timeline_init(struct drm_i915_private *i915,
>   	i915_syncmap_init(&timeline->sync);
>   }
>   
> +void i915_timelines_init(struct drm_i915_private *i915)
> +{
> +	struct i915_gt_timelines *gt = &i915->gt.timelines;
> +
> +	mutex_init(&gt->mutex);
> +	INIT_LIST_HEAD(&gt->list);
> +
> +	/* via i915_gem_wait_for_idle() */
> +	i915_gem_shrinker_taints_mutex(i915, &gt->mutex);
> +}
> +
>   /**
>    * i915_timelines_park - called when the driver idles
>    * @i915: the drm_i915_private device
> @@ -51,11 +65,11 @@ void i915_timeline_init(struct drm_i915_private *i915,
>    */
>   void i915_timelines_park(struct drm_i915_private *i915)
>   {
> +	struct i915_gt_timelines *gt = &i915->gt.timelines;
>   	struct i915_timeline *timeline;
>   
> -	lockdep_assert_held(&i915->drm.struct_mutex);
> -
> -	list_for_each_entry(timeline, &i915->gt.timelines, link) {
> +	mutex_lock(&gt->mutex);
> +	list_for_each_entry(timeline, &gt->list, link) {
>   		/*
>   		 * All known fences are completed so we can scrap
>   		 * the current sync point tracking and start afresh,
> @@ -64,15 +78,20 @@ void i915_timelines_park(struct drm_i915_private *i915)
>   		 */
>   		i915_syncmap_free(&timeline->sync);
>   	}
> +	mutex_unlock(&gt->mutex);
>   }
>   
>   void i915_timeline_fini(struct i915_timeline *timeline)
>   {
> +	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
> +
>   	GEM_BUG_ON(!list_empty(&timeline->requests));
>   
>   	i915_syncmap_free(&timeline->sync);
>   
> +	mutex_lock(&gt->mutex);
>   	list_del(&timeline->link);
> +	mutex_unlock(&gt->mutex);
>   }
>   
>   struct i915_timeline *
> @@ -99,6 +118,15 @@ void __i915_timeline_free(struct kref *kref)
>   	kfree(timeline);
>   }
>   
> +void i915_timelines_fini(struct drm_i915_private *i915)
> +{
> +	struct i915_gt_timelines *gt = &i915->gt.timelines;
> +
> +	GEM_BUG_ON(!list_empty(&gt->list));
> +
> +	mutex_destroy(&gt->mutex);
> +}
> +
>   #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
>   #include "selftests/mock_timeline.c"
>   #include "selftests/i915_timeline.c"
> diff --git a/drivers/gpu/drm/i915/i915_timeline.h b/drivers/gpu/drm/i915/i915_timeline.h
> index 38c1e15e927a..87ad2dd31c20 100644
> --- a/drivers/gpu/drm/i915/i915_timeline.h
> +++ b/drivers/gpu/drm/i915/i915_timeline.h
> @@ -66,6 +66,7 @@ struct i915_timeline {
>   
>   	struct list_head link;
>   	const char *name;
> +	struct drm_i915_private *i915;
>   
>   	struct kref kref;
>   };
> @@ -134,6 +135,8 @@ static inline bool i915_timeline_sync_is_later(struct i915_timeline *tl,
>   	return __i915_timeline_sync_is_later(tl, fence->context, fence->seqno);
>   }
>   
> +void i915_timelines_init(struct drm_i915_private *i915);
>   void i915_timelines_park(struct drm_i915_private *i915);
> +void i915_timelines_fini(struct drm_i915_private *i915);
>   
>   #endif
> diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
> index 3a680fe2bb8b..d83b8ad5f859 100644
> --- a/drivers/gpu/drm/i915/i915_vma.c
> +++ b/drivers/gpu/drm/i915/i915_vma.c
> @@ -201,6 +201,11 @@ vma_create(struct drm_i915_gem_object *obj,
>   		rb = *p;
>   		pos = rb_entry(rb, struct i915_vma, obj_node);
>   
> +		/*
> +		 * If the view already exists in the tree, another thread
> +		 * already created a matching vma, so return the older instance
> +		 * and dispose of ours.
> +		 */

Oh here is the lost comment, all alone in the strange world. :)

>   		cmp = i915_vma_compare(pos, vm, view);
>   		if (cmp == 0) {
>   			spin_unlock(&obj->vma.lock);
> @@ -294,6 +299,7 @@ i915_vma_instance(struct drm_i915_gem_object *obj,
>   	vma = vma_lookup(obj, vm, view);
>   	spin_unlock(&obj->vma.lock);
>   
> +	/* vma_create() will resolve the race if another creates the vma */

I assume you'll move both comments to their right place.

>   	if (unlikely(!vma))
>   		vma = vma_create(obj, vm, view);
>   
> diff --git a/drivers/gpu/drm/i915/selftests/mock_gem_device.c b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
> index 888c6978bc54..41ae502361d7 100644
> --- a/drivers/gpu/drm/i915/selftests/mock_gem_device.c
> +++ b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
> @@ -68,13 +68,14 @@ static void mock_device_release(struct drm_device *dev)
>   	i915_gem_contexts_fini(i915);
>   	mutex_unlock(&i915->drm.struct_mutex);
>   
> +	i915_timelines_fini(i915);
> +
>   	drain_workqueue(i915->wq);
>   	i915_gem_drain_freed_objects(i915);
>   
>   	mutex_lock(&i915->drm.struct_mutex);
>   	mock_fini_ggtt(i915);
>   	mutex_unlock(&i915->drm.struct_mutex);
> -	WARN_ON(!list_empty(&i915->gt.timelines));
>   
>   	destroy_workqueue(i915->wq);
>   
> @@ -226,7 +227,8 @@ struct drm_i915_private *mock_gem_device(void)
>   	if (!i915->priorities)
>   		goto err_dependencies;
>   
> -	INIT_LIST_HEAD(&i915->gt.timelines);
> +	i915_timelines_init(i915);
> +
>   	INIT_LIST_HEAD(&i915->gt.active_rings);
>   	INIT_LIST_HEAD(&i915->gt.closed_vma);
>   
> @@ -253,6 +255,7 @@ struct drm_i915_private *mock_gem_device(void)
>   	i915_gem_contexts_fini(i915);
>   err_unlock:
>   	mutex_unlock(&i915->drm.struct_mutex);
> +	i915_timelines_fini(i915);
>   	kmem_cache_destroy(i915->priorities);
>   err_dependencies:
>   	kmem_cache_destroy(i915->dependencies);
> diff --git a/drivers/gpu/drm/i915/selftests/mock_timeline.c b/drivers/gpu/drm/i915/selftests/mock_timeline.c
> index dcf3b16f5a07..cf39ccd9fc05 100644
> --- a/drivers/gpu/drm/i915/selftests/mock_timeline.c
> +++ b/drivers/gpu/drm/i915/selftests/mock_timeline.c
> @@ -10,6 +10,7 @@
>   
>   void mock_timeline_init(struct i915_timeline *timeline, u64 context)
>   {
> +	timeline->i915 = NULL;
>   	timeline->fence_context = context;
>   
>   	spin_lock_init(&timeline->lock);
> @@ -24,5 +25,5 @@ void mock_timeline_init(struct i915_timeline *timeline, u64 context)
>   
>   void mock_timeline_fini(struct i915_timeline *timeline)
>   {
> -	i915_timeline_fini(timeline);
> +	i915_syncmap_free(&timeline->sync);
>   }
> 

Looks okay.

Apart that I am 9/10 worried of how the long game of fine grained 
locking will untangle, or in other words, how much you managed to nail 
all the new locks and how much you'll have to re-fiddle with them. :I 
But maybe you see the end game so I won't project my inability to do so.

Regards,

Tvrtko
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 09/23] drm/i915: Use b->irq_enable() as predicate for mock engine
  2019-01-17 16:52     ` Chris Wilson
@ 2019-01-17 18:00       ` Tvrtko Ursulin
  0 siblings, 0 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-17 18:00 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 16:52, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2019-01-17 16:44:54)
>>
>> On 17/01/2019 14:34, Chris Wilson wrote:
>>> Since commit  d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")
>>> we have required a mechanism to avoid touching the interrupt hardware
>>> for breadcrumbs, superseding our mock interface for selftests.
>>>
>>> References: d4ccceb05591 ("drm/i915/icl: Ringbuffer interrupt handling")
>>> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>>> ---
>>>    drivers/gpu/drm/i915/intel_breadcrumbs.c     | 39 ++++++++------------
>>>    drivers/gpu/drm/i915/intel_engine_cs.c       | 11 ++----
>>>    drivers/gpu/drm/i915/intel_ringbuffer.h      |  1 -
>>>    drivers/gpu/drm/i915/selftests/mock_engine.c |  1 -
>>>    4 files changed, 20 insertions(+), 32 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c
>>> index 4ed7105d7ff5..7b517bf83507 100644
>>> --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c
>>> +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
>>> @@ -158,6 +158,9 @@ static void intel_breadcrumbs_fake_irq(struct timer_list *t)
>>>    
>>>    static void irq_enable(struct intel_engine_cs *engine)
>>>    {
>>> +     if (!engine->irq_enable)
>>> +             return;
>>> +
>>>        /*
>>>         * FIXME: Ideally we want this on the API boundary, but for the
>>>         * sake of testing with mock breadcrumbs (no HW so unable to
>>
>> Okay I think I misunderstood this patch in the last round. So you want
>> to avoid the GEM_BUG_ON below _and_ a dedicated boolean only for the
>> mock engine.
>>
>> I only wonder on the remaining merit of this comment and actually a
>> GEM_BUG_ON, which will be hit and miss depending on the platform now.
>> Gut feeling says something is still not ideal here. Selftests variable
>> does actually feel better in this sense.
>>
>> mock_engine seems only used from mock_gem_device, so could an
>> alternative be to set i915->runtime_pm.irqs_enabled there and keep the
>> GEM_BUG_ON in irq_enable above the !engine->irq_enable early return?
>> That would still provide the unconditional assert on the state of the
>> driver outside selftests.
> 
> I'm just going to kill the mention of irqs enabled here, eventually. It
> was interesting once because we messed up suspend a decade ago and had to
> handle the case of waiting after we had already uninstalled the irq
> handler.
> 
> This is nothing to do with irqs_enabled; the selftest variable was all
> because the mock engine had no engine->irq_enable() callback, and now it
> is not the only engine so the assumption that we must always have
> engine->irq_enable() is invalid.

Okay, my complaint was minimal anyway:

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* ✗ Fi.CI.IGT: failure for series starting with [01/23] drm/i915: Make all GPU resets atomic
  2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
                   ` (26 preceding siblings ...)
  2019-01-17 15:38 ` ✓ Fi.CI.BAT: success " Patchwork
@ 2019-01-17 23:36 ` Patchwork
  2019-01-17 23:41   ` Chris Wilson
  27 siblings, 1 reply; 50+ messages in thread
From: Patchwork @ 2019-01-17 23:36 UTC (permalink / raw)
  To: Chris Wilson; +Cc: intel-gfx

== Series Details ==

Series: series starting with [01/23] drm/i915: Make all GPU resets atomic
URL   : https://patchwork.freedesktop.org/series/55365/
State : failure

== Summary ==

CI Bug Log - changes from CI_DRM_5440_full -> Patchwork_11970_full
====================================================

Summary
-------

  **FAILURE**

  Serious unknown changes coming with Patchwork_11970_full absolutely need to be
  verified manually.
  
  If you think the reported changes have nothing to do with the changes
  introduced in Patchwork_11970_full, please notify your bug team to allow them
  to document this new failure mode, which will reduce false positives in CI.

  

Possible new issues
-------------------

  Here are the unknown changes that may have been introduced in Patchwork_11970_full:

### IGT changes ###

#### Possible regressions ####

  * igt@gem_mmap_gtt@hang:
    - shard-snb:          PASS -> FAIL

  
Known issues
------------

  Here are the changes found in Patchwork_11970_full that come from known issues:

### IGT changes ###

#### Issues hit ####

  * igt@gem_exec_schedule@pi-ringfull-vebox:
    - shard-skl:          NOTRUN -> FAIL [fdo#103158]

  * igt@i915_selftest@live_workarounds:
    - shard-iclb:         PASS -> DMESG-FAIL [fdo#108954]

  * igt@i915_suspend@shrink:
    - shard-skl:          NOTRUN -> INCOMPLETE [fdo#106886]
    - shard-iclb:         NOTRUN -> DMESG-WARN [fdo#107886] / [fdo#109244]

  * igt@kms_busy@extended-modeset-hang-newfb-with-reset-render-a:
    - shard-iclb:         NOTRUN -> DMESG-WARN [fdo#107956]
    - shard-skl:          NOTRUN -> DMESG-WARN [fdo#107956] +1

  * igt@kms_ccs@pipe-a-crc-primary-basic:
    - shard-iclb:         NOTRUN -> FAIL [fdo#107725]

  * igt@kms_color@pipe-a-ctm-max:
    - shard-apl:          PASS -> FAIL [fdo#108147]

  * igt@kms_color@pipe-a-degamma:
    - shard-apl:          PASS -> FAIL [fdo#104782] / [fdo#108145]

  * igt@kms_color@pipe-b-legacy-gamma:
    - shard-apl:          PASS -> FAIL [fdo#104782]

  * igt@kms_cursor_crc@cursor-64x21-sliding:
    - shard-apl:          PASS -> FAIL [fdo#103232] +6

  * igt@kms_cursor_crc@cursor-size-change:
    - shard-glk:          PASS -> FAIL [fdo#103232] +2

  * igt@kms_flip@modeset-vs-vblank-race:
    - shard-glk:          PASS -> FAIL [fdo#103060]

  * igt@kms_frontbuffer_tracking@fbc-1p-primscrn-spr-indfb-draw-blt:
    - shard-iclb:         NOTRUN -> FAIL [fdo#103167] +1

  * igt@kms_frontbuffer_tracking@fbc-1p-primscrn-spr-indfb-draw-mmap-gtt:
    - shard-apl:          PASS -> FAIL [fdo#103167] +4

  * igt@kms_frontbuffer_tracking@fbc-1p-rte:
    - shard-apl:          PASS -> FAIL [fdo#103167] / [fdo#105682]

  * igt@kms_frontbuffer_tracking@fbc-2p-primscrn-cur-indfb-move:
    - shard-glk:          PASS -> FAIL [fdo#103167] +2

  * igt@kms_frontbuffer_tracking@fbcpsr-1p-primscrn-pri-shrfb-draw-mmap-wc:
    - shard-skl:          NOTRUN -> FAIL [fdo#103167] +5

  * igt@kms_frontbuffer_tracking@fbcpsr-1p-primscrn-spr-indfb-draw-render:
    - shard-iclb:         PASS -> FAIL [fdo#103167] +1

  * igt@kms_pipe_crc_basic@suspend-read-crc-pipe-b:
    - shard-skl:          NOTRUN -> FAIL [fdo#103191] / [fdo#107362]

  * igt@kms_plane@pixel-format-pipe-a-planes-source-clamping:
    - shard-apl:          PASS -> FAIL [fdo#108948]

  * igt@kms_plane@plane-panning-bottom-right-pipe-a-planes:
    - shard-skl:          NOTRUN -> FAIL [fdo#103166]

  * igt@kms_plane_alpha_blend@pipe-a-constant-alpha-min:
    - shard-skl:          NOTRUN -> FAIL [fdo#108145] +1

  * igt@kms_plane_multiple@atomic-pipe-a-tiling-x:
    - shard-apl:          PASS -> FAIL [fdo#103166]
    - shard-glk:          PASS -> FAIL [fdo#103166]
    - shard-iclb:         PASS -> FAIL [fdo#103166]

  * igt@kms_rotation_crc@multiplane-rotation-cropping-top:
    - shard-apl:          PASS -> DMESG-FAIL [fdo#108950]

  * igt@kms_rotation_crc@primary-rotation-180:
    - shard-skl:          PASS -> FAIL [fdo#103925] / [fdo#107815]

  * igt@kms_setmode@basic:
    - shard-apl:          PASS -> FAIL [fdo#99912]

  * igt@pm_rpm@system-suspend:
    - shard-skl:          NOTRUN -> INCOMPLETE [fdo#104108] / [fdo#107807]

  * igt@pm_rpm@universal-planes-dpms:
    - shard-iclb:         PASS -> DMESG-WARN [fdo#107724]

  
#### Possible fixes ####

  * igt@debugfs_test@read_all_entries_display_off:
    - shard-skl:          INCOMPLETE [fdo#104108] -> PASS

  * igt@kms_atomic_transition@plane-all-modeset-transition-internal-panels:
    - shard-iclb:         DMESG-WARN [fdo#107724] -> PASS +2

  * igt@kms_color@pipe-a-legacy-gamma:
    - shard-apl:          FAIL [fdo#104782] / [fdo#108145] -> PASS

  * igt@kms_cursor_crc@cursor-128x128-suspend:
    - shard-glk:          FAIL [fdo#103232] -> PASS +2
    - shard-apl:          FAIL [fdo#103191] / [fdo#103232] -> PASS

  * igt@kms_cursor_crc@cursor-64x21-random:
    - shard-apl:          FAIL [fdo#103232] -> PASS +3

  * igt@kms_cursor_legacy@2x-long-cursor-vs-flip-atomic:
    - shard-hsw:          FAIL [fdo#105767] -> PASS

  * igt@kms_flip_event_leak:
    - shard-kbl:          DMESG-WARN [fdo#103558] / [fdo#105602] -> PASS +4

  * igt@kms_frontbuffer_tracking@fbc-1p-primscrn-cur-indfb-draw-blt:
    - shard-apl:          FAIL [fdo#103167] -> PASS

  * igt@kms_frontbuffer_tracking@fbc-1p-primscrn-spr-indfb-draw-mmap-cpu:
    - shard-iclb:         FAIL [fdo#103167] -> PASS

  * igt@kms_frontbuffer_tracking@fbc-2p-rte:
    - shard-glk:          FAIL [fdo#103167] / [fdo#105682] -> PASS

  * igt@kms_frontbuffer_tracking@fbc-rgb565-draw-render:
    - shard-glk:          FAIL [fdo#103167] -> PASS +3

  * igt@kms_plane@plane-panning-bottom-right-pipe-a-planes:
    - shard-iclb:         DMESG-WARN [fdo#107724] / [fdo#108336] -> PASS +2

  * igt@kms_plane_multiple@atomic-pipe-c-tiling-yf:
    - shard-apl:          FAIL [fdo#103166] -> PASS +4

  * igt@pm_rc6_residency@rc6-accuracy:
    - shard-kbl:          {SKIP} [fdo#109271] -> PASS

  * igt@pm_rpm@gem-execbuf-stress:
    - shard-skl:          INCOMPLETE [fdo#107803] / [fdo#107807] -> PASS

  
#### Warnings ####

  * igt@kms_pipe_crc_basic@nonblocking-crc-pipe-a-frame-sequence:
    - shard-snb:          DMESG-WARN [fdo#107469] -> INCOMPLETE [fdo#105411]

  * igt@kms_rotation_crc@multiplane-rotation-cropping-top:
    - shard-iclb:         FAIL -> DMESG-FAIL [fdo#107724]

  * igt@pm_backlight@fade_with_suspend:
    - shard-iclb:         FAIL [fdo#107847] -> INCOMPLETE [fdo#107713] / [fdo#107820]

  
  {name}: This element is suppressed. This means it is ignored when computing
          the status of the difference (SUCCESS, WARNING, or FAILURE).

  [fdo#103060]: https://bugs.freedesktop.org/show_bug.cgi?id=103060
  [fdo#103158]: https://bugs.freedesktop.org/show_bug.cgi?id=103158
  [fdo#103166]: https://bugs.freedesktop.org/show_bug.cgi?id=103166
  [fdo#103167]: https://bugs.freedesktop.org/show_bug.cgi?id=103167
  [fdo#103191]: https://bugs.freedesktop.org/show_bug.cgi?id=103191
  [fdo#103232]: https://bugs.freedesktop.org/show_bug.cgi?id=103232
  [fdo#103558]: https://bugs.freedesktop.org/show_bug.cgi?id=103558
  [fdo#103925]: https://bugs.freedesktop.org/show_bug.cgi?id=103925
  [fdo#104108]: https://bugs.freedesktop.org/show_bug.cgi?id=104108
  [fdo#104782]: https://bugs.freedesktop.org/show_bug.cgi?id=104782
  [fdo#105411]: https://bugs.freedesktop.org/show_bug.cgi?id=105411
  [fdo#105602]: https://bugs.freedesktop.org/show_bug.cgi?id=105602
  [fdo#105682]: https://bugs.freedesktop.org/show_bug.cgi?id=105682
  [fdo#105767]: https://bugs.freedesktop.org/show_bug.cgi?id=105767
  [fdo#106886]: https://bugs.freedesktop.org/show_bug.cgi?id=106886
  [fdo#107362]: https://bugs.freedesktop.org/show_bug.cgi?id=107362
  [fdo#107469]: https://bugs.freedesktop.org/show_bug.cgi?id=107469
  [fdo#107713]: https://bugs.freedesktop.org/show_bug.cgi?id=107713
  [fdo#107724]: https://bugs.freedesktop.org/show_bug.cgi?id=107724
  [fdo#107725]: https://bugs.freedesktop.org/show_bug.cgi?id=107725
  [fdo#107803]: https://bugs.freedesktop.org/show_bug.cgi?id=107803
  [fdo#107807]: https://bugs.freedesktop.org/show_bug.cgi?id=107807
  [fdo#107815]: https://bugs.freedesktop.org/show_bug.cgi?id=107815
  [fdo#107820]: https://bugs.freedesktop.org/show_bug.cgi?id=107820
  [fdo#107847]: https://bugs.freedesktop.org/show_bug.cgi?id=107847
  [fdo#107886]: https://bugs.freedesktop.org/show_bug.cgi?id=107886
  [fdo#107956]: https://bugs.freedesktop.org/show_bug.cgi?id=107956
  [fdo#108145]: https://bugs.freedesktop.org/show_bug.cgi?id=108145
  [fdo#108147]: https://bugs.freedesktop.org/show_bug.cgi?id=108147
  [fdo#108336]: https://bugs.freedesktop.org/show_bug.cgi?id=108336
  [fdo#108948]: https://bugs.freedesktop.org/show_bug.cgi?id=108948
  [fdo#108950]: https://bugs.freedesktop.org/show_bug.cgi?id=108950
  [fdo#108954]: https://bugs.freedesktop.org/show_bug.cgi?id=108954
  [fdo#109244]: https://bugs.freedesktop.org/show_bug.cgi?id=109244
  [fdo#109271]: https://bugs.freedesktop.org/show_bug.cgi?id=109271
  [fdo#109274]: https://bugs.freedesktop.org/show_bug.cgi?id=109274
  [fdo#109275]: https://bugs.freedesktop.org/show_bug.cgi?id=109275
  [fdo#109276]: https://bugs.freedesktop.org/show_bug.cgi?id=109276
  [fdo#109278]: https://bugs.freedesktop.org/show_bug.cgi?id=109278
  [fdo#109279]: https://bugs.freedesktop.org/show_bug.cgi?id=109279
  [fdo#109280]: https://bugs.freedesktop.org/show_bug.cgi?id=109280
  [fdo#109281]: https://bugs.freedesktop.org/show_bug.cgi?id=109281
  [fdo#109284]: https://bugs.freedesktop.org/show_bug.cgi?id=109284
  [fdo#109286]: https://bugs.freedesktop.org/show_bug.cgi?id=109286
  [fdo#109287]: https://bugs.freedesktop.org/show_bug.cgi?id=109287
  [fdo#109289]: https://bugs.freedesktop.org/show_bug.cgi?id=109289
  [fdo#109290]: https://bugs.freedesktop.org/show_bug.cgi?id=109290
  [fdo#109291]: https://bugs.freedesktop.org/show_bug.cgi?id=109291
  [fdo#109300]: https://bugs.freedesktop.org/show_bug.cgi?id=109300
  [fdo#109315]: https://bugs.freedesktop.org/show_bug.cgi?id=109315
  [fdo#99912]: https://bugs.freedesktop.org/show_bug.cgi?id=99912


Participating hosts (7 -> 7)
------------------------------

  No changes in participating hosts


Build changes
-------------

    * Linux: CI_DRM_5440 -> Patchwork_11970

  CI_DRM_5440: b36a89b5ab74fd49a4369e6df0d2c02bc464a474 @ git://anongit.freedesktop.org/gfx-ci/linux
  IGT_4777: 8614d5eb114a660c3bd7ff77eab8bed53424cd30 @ git://anongit.freedesktop.org/xorg/app/intel-gpu-tools
  Patchwork_11970: f7e648e4bba87e1ddbeb45b377ec4470562fb286 @ git://anongit.freedesktop.org/gfx-ci/linux
  piglit_4509: fdc5a4ca11124ab8413c7988896eec4c97336694 @ git://anongit.freedesktop.org/piglit

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_11970/
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: ✗ Fi.CI.IGT: failure for series starting with [01/23] drm/i915: Make all GPU resets atomic
  2019-01-17 23:36 ` ✗ Fi.CI.IGT: failure " Patchwork
@ 2019-01-17 23:41   ` Chris Wilson
  0 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-17 23:41 UTC (permalink / raw)
  To: Patchwork; +Cc: intel-gfx

Quoting Patchwork (2019-01-17 23:36:23)
> #### Possible regressions ####
> 
>   * igt@gem_mmap_gtt@hang:
>     - shard-snb:          PASS -> FAIL

The only thing unexpected here is that they all didn't fail. (Dropping
this protection of disabling memory access while the fence registers are
being reset is a shortcoming of not being able to take a common mutex in
i915_gem_fault and reset due to the memory allocations required to setup
the CPU PTEs.)

I guess I should ensure that this test always fails so we don't get
annoying flip-flops.
-Chris
_______________________________________________
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 07/23] drm/i915: Pull VM lists under the VM mutex.
  2019-01-17 14:34 ` [PATCH 07/23] drm/i915: Pull VM lists under the VM mutex Chris Wilson
@ 2019-01-18 10:07   ` Tvrtko Ursulin
  0 siblings, 0 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-18 10:07 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> A starting point to counter the pervasive struct_mutex. For the goal of
> avoiding (or at least blocking under them!) global locks during user
> request submission, a simple but important step is being able to manage
> each clients GTT separately. For which, we want to replace using the
> struct_mutex as the guard for all things GTT/VM and switch instead to a
> specific mutex inside i915_address_space.
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_gem.c                 | 14 ++++++++------
>   drivers/gpu/drm/i915/i915_gem_evict.c           |  2 ++
>   drivers/gpu/drm/i915/i915_gem_gtt.c             | 15 +++++++++++++--
>   drivers/gpu/drm/i915/i915_gem_shrinker.c        |  4 ++++
>   drivers/gpu/drm/i915/i915_gem_stolen.c          |  2 ++
>   drivers/gpu/drm/i915/i915_vma.c                 | 11 +++++++++++
>   drivers/gpu/drm/i915/selftests/i915_gem_evict.c |  3 +++
>   drivers/gpu/drm/i915/selftests/i915_gem_gtt.c   |  3 +++
>   8 files changed, 46 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index f45186ddb236..538fa5404603 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -245,18 +245,19 @@ int
>   i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
>   			    struct drm_file *file)
>   {
> -	struct drm_i915_private *dev_priv = to_i915(dev);
> -	struct i915_ggtt *ggtt = &dev_priv->ggtt;
> +	struct i915_ggtt *ggtt = &to_i915(dev)->ggtt;
>   	struct drm_i915_gem_get_aperture *args = data;
>   	struct i915_vma *vma;
>   	u64 pinned;
>   
> +	mutex_lock(&ggtt->vm.mutex);
> +
>   	pinned = ggtt->vm.reserved;
> -	mutex_lock(&dev->struct_mutex);
>   	list_for_each_entry(vma, &ggtt->vm.bound_list, vm_link)
>   		if (i915_vma_is_pinned(vma))
>   			pinned += vma->node.size;
> -	mutex_unlock(&dev->struct_mutex);
> +
> +	mutex_unlock(&ggtt->vm.mutex);
>   
>   	args->aper_size = ggtt->vm.total;
>   	args->aper_available_size = args->aper_size - pinned;
> @@ -1529,20 +1530,21 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
>   
>   static void i915_gem_object_bump_inactive_ggtt(struct drm_i915_gem_object *obj)
>   {
> -	struct drm_i915_private *i915;
> +	struct drm_i915_private *i915 = to_i915(obj->base.dev);
>   	struct list_head *list;
>   	struct i915_vma *vma;
>   
>   	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
>   
> +	mutex_lock(&i915->ggtt.vm.mutex);
>   	for_each_ggtt_vma(vma, obj) {
>   		if (!drm_mm_node_allocated(&vma->node))
>   			continue;
>   
>   		list_move_tail(&vma->vm_link, &vma->vm->bound_list);
>   	}
> +	mutex_unlock(&i915->ggtt.vm.mutex);
>   
> -	i915 = to_i915(obj->base.dev);
>   	spin_lock(&i915->mm.obj_lock);
>   	list = obj->bind_count ? &i915->mm.bound_list : &i915->mm.unbound_list;
>   	list_move_tail(&obj->mm.link, list);
> diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
> index 5cfe4b75e7d6..dc137701acb8 100644
> --- a/drivers/gpu/drm/i915/i915_gem_evict.c
> +++ b/drivers/gpu/drm/i915/i915_gem_evict.c
> @@ -432,6 +432,7 @@ int i915_gem_evict_vm(struct i915_address_space *vm)
>   	}
>   
>   	INIT_LIST_HEAD(&eviction_list);
> +	mutex_lock(&vm->mutex);
>   	list_for_each_entry(vma, &vm->bound_list, vm_link) {
>   		if (i915_vma_is_pinned(vma))
>   			continue;
> @@ -439,6 +440,7 @@ int i915_gem_evict_vm(struct i915_address_space *vm)
>   		__i915_vma_pin(vma);
>   		list_add(&vma->evict_link, &eviction_list);
>   	}
> +	mutex_unlock(&vm->mutex);
>   
>   	ret = 0;
>   	list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> index 2ad9070a54c1..49b00996a15e 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> @@ -1931,7 +1931,10 @@ static struct i915_vma *pd_vma_create(struct gen6_hw_ppgtt *ppgtt, int size)
>   	vma->ggtt_view.type = I915_GGTT_VIEW_ROTATED; /* prevent fencing */
>   
>   	INIT_LIST_HEAD(&vma->obj_link);
> +
> +	mutex_lock(&vma->vm->mutex);
>   	list_add(&vma->vm_link, &vma->vm->unbound_list);
> +	mutex_unlock(&vma->vm->mutex);
>   
>   	return vma;
>   }
> @@ -3504,9 +3507,10 @@ void i915_gem_restore_gtt_mappings(struct drm_i915_private *dev_priv)
>   
>   	i915_check_and_clear_faults(dev_priv);
>   
> +	mutex_lock(&ggtt->vm.mutex);
> +
>   	/* First fill our portion of the GTT with scratch pages */
>   	ggtt->vm.clear_range(&ggtt->vm, 0, ggtt->vm.total);
> -
>   	ggtt->vm.closed = true; /* skip rewriting PTE on VMA unbind */
>   
>   	/* clflush objects bound into the GGTT and rebind them. */
> @@ -3516,19 +3520,26 @@ void i915_gem_restore_gtt_mappings(struct drm_i915_private *dev_priv)
>   		if (!(vma->flags & I915_VMA_GLOBAL_BIND))
>   			continue;
>   
> +		mutex_unlock(&ggtt->vm.mutex);
> +
>   		if (!i915_vma_unbind(vma))
> -			continue;
> +			goto lock;
>   
>   		WARN_ON(i915_vma_bind(vma,
>   				      obj ? obj->cache_level : 0,
>   				      PIN_UPDATE));
>   		if (obj)
>   			WARN_ON(i915_gem_object_set_to_gtt_domain(obj, false));
> +
> +lock:
> +		mutex_lock(&ggtt->vm.mutex);
>   	}
>   
>   	ggtt->vm.closed = false;
>   	i915_ggtt_invalidate(dev_priv);
>   
> +	mutex_unlock(&ggtt->vm.mutex);
> +
>   	if (INTEL_GEN(dev_priv) >= 8) {
>   		struct intel_ppat *ppat = &dev_priv->ppat;
>   
> diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c
> index a76d6c95c824..6da795c7e62e 100644
> --- a/drivers/gpu/drm/i915/i915_gem_shrinker.c
> +++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c
> @@ -461,6 +461,7 @@ i915_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr
>   					       I915_SHRINK_VMAPS);
>   
>   	/* We also want to clear any cached iomaps as they wrap vmap */
> +	mutex_lock(&i915->ggtt.vm.mutex);
>   	list_for_each_entry_safe(vma, next,
>   				 &i915->ggtt.vm.bound_list, vm_link) {
>   		unsigned long count = vma->node.size >> PAGE_SHIFT;
> @@ -468,9 +469,12 @@ i915_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr
>   		if (!vma->iomap || i915_vma_is_active(vma))
>   			continue;
>   
> +		mutex_unlock(&i915->ggtt.vm.mutex);
>   		if (i915_vma_unbind(vma) == 0)
>   			freed_pages += count;
> +		mutex_lock(&i915->ggtt.vm.mutex);
>   	}
> +	mutex_unlock(&i915->ggtt.vm.mutex);
>   
>   out:
>   	shrinker_unlock(i915, unlock);
> diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> index a9e365789686..74a9661479ca 100644
> --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> @@ -702,7 +702,9 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *dev_priv
>   	vma->flags |= I915_VMA_GLOBAL_BIND;
>   	__i915_vma_set_map_and_fenceable(vma);
>   
> +	mutex_lock(&ggtt->vm.mutex);
>   	list_move_tail(&vma->vm_link, &ggtt->vm.bound_list);
> +	mutex_unlock(&ggtt->vm.mutex);
>   
>   	spin_lock(&dev_priv->mm.obj_lock);
>   	list_move_tail(&obj->mm.link, &dev_priv->mm.bound_list);
> diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
> index 7de28baffb8f..dcbd0d345c72 100644
> --- a/drivers/gpu/drm/i915/i915_vma.c
> +++ b/drivers/gpu/drm/i915/i915_vma.c
> @@ -213,7 +213,10 @@ vma_create(struct drm_i915_gem_object *obj,
>   	}
>   	rb_link_node(&vma->obj_node, rb, p);
>   	rb_insert_color(&vma->obj_node, &obj->vma_tree);
> +
> +	mutex_lock(&vm->mutex);
>   	list_add(&vma->vm_link, &vm->unbound_list);
> +	mutex_unlock(&vm->mutex);
>   
>   	return vma;
>   
> @@ -656,7 +659,9 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
>   	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
>   	GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, cache_level));
>   
> +	mutex_lock(&vma->vm->mutex);
>   	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
> +	mutex_unlock(&vma->vm->mutex);
>   
>   	if (vma->obj) {
>   		struct drm_i915_gem_object *obj = vma->obj;
> @@ -689,8 +694,10 @@ i915_vma_remove(struct i915_vma *vma)
>   
>   	vma->ops->clear_pages(vma);
>   
> +	mutex_lock(&vma->vm->mutex);
>   	drm_mm_remove_node(&vma->node);
>   	list_move_tail(&vma->vm_link, &vma->vm->unbound_list);
> +	mutex_unlock(&vma->vm->mutex);
>   
>   	/*
>   	 * Since the unbound list is global, only move to that list if
> @@ -802,7 +809,11 @@ static void __i915_vma_destroy(struct i915_vma *vma)
>   	GEM_BUG_ON(i915_gem_active_isset(&vma->last_fence));
>   
>   	list_del(&vma->obj_link);
> +
> +	mutex_lock(&vma->vm->mutex);
>   	list_del(&vma->vm_link);
> +	mutex_unlock(&vma->vm->mutex);
> +
>   	if (vma->obj)
>   		rb_erase(&vma->obj_node, &vma->obj->vma_tree);
>   
> diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> index 6c9c7a1c2728..fb7df895afeb 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> +++ b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> @@ -67,10 +67,13 @@ static int populate_ggtt(struct drm_i915_private *i915)
>   
>   static void unpin_ggtt(struct drm_i915_private *i915)
>   {
> +	struct i915_ggtt *ggtt = &i915->ggtt;
>   	struct i915_vma *vma;
>   
> +	mutex_lock(&ggtt->vm.mutex);
>   	list_for_each_entry(vma, &i915->ggtt.vm.bound_list, vm_link)
>   		i915_vma_unpin(vma);
> +	mutex_unlock(&ggtt->vm.mutex);
>   }
>   
>   static void cleanup_objects(struct drm_i915_private *i915)
> diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
> index 852b06cb50a0..35eb40e5de91 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
> @@ -1237,7 +1237,10 @@ static void track_vma_bind(struct i915_vma *vma)
>   	__i915_gem_object_pin_pages(obj);
>   
>   	vma->pages = obj->mm.pages;
> +
> +	mutex_lock(&vma->vm->mutex);
>   	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
> +	mutex_unlock(&vma->vm->mutex);
>   }
>   
>   static int exercise_mock(struct drm_i915_private *i915,
> 

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 14/23] drm/i915: Introduce concept of per-timeline (context) HWSP
  2019-01-17 14:34 ` [PATCH 14/23] drm/i915: Introduce concept of per-timeline (context) HWSP Chris Wilson
@ 2019-01-18 10:18   ` Tvrtko Ursulin
  0 siblings, 0 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-18 10:18 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> Supplement the per-engine HWSP with a per-timeline HWSP. That is a
> per-request pointer through which we can check a local seqno,
> abstracting away the presumption of a global seqno. In this first step,
> we point each request back into the engine's HWSP so everything
> continues to work with the global timeline.
> 
> v2: s/i915_request_hwsp/hwsp_seqno/ to emphasis that this is the current
> HW value and that we are accessing it via i915_request merely as a
> convenience.
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_request.c | 16 +++++++++-----
>   drivers/gpu/drm/i915/i915_request.h | 34 +++++++++++++++++++++++------
>   drivers/gpu/drm/i915/intel_lrc.c    |  9 +++++---
>   3 files changed, 44 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
> index fb723ed2f574..7d068c406a49 100644
> --- a/drivers/gpu/drm/i915/i915_request.c
> +++ b/drivers/gpu/drm/i915/i915_request.c
> @@ -182,10 +182,11 @@ static void free_capture_list(struct i915_request *request)
>   static void __retire_engine_request(struct intel_engine_cs *engine,
>   				    struct i915_request *rq)
>   {
> -	GEM_TRACE("%s(%s) fence %llx:%lld, global=%d, current %d\n",
> +	GEM_TRACE("%s(%s) fence %llx:%lld, global=%d, current %d:%d\n",

I'd maybe use something other than a colon as a seqno separator, like 
'/', to designate it is a different hierarchical relationship than 
class:instance. But I have a feeling this will be going away by the end 
of the series so never mind.

>   		  __func__, engine->name,
>   		  rq->fence.context, rq->fence.seqno,
>   		  rq->global_seqno,
> +		  hwsp_seqno(rq),
>   		  intel_engine_get_seqno(engine));
>   
>   	GEM_BUG_ON(!i915_request_completed(rq));
> @@ -244,10 +245,11 @@ static void i915_request_retire(struct i915_request *request)
>   {
>   	struct i915_gem_active *active, *next;
>   
> -	GEM_TRACE("%s fence %llx:%lld, global=%d, current %d\n",
> +	GEM_TRACE("%s fence %llx:%lld, global=%d, current %d:%d\n",
>   		  request->engine->name,
>   		  request->fence.context, request->fence.seqno,
>   		  request->global_seqno,
> +		  hwsp_seqno(request),
>   		  intel_engine_get_seqno(request->engine));
>   
>   	lockdep_assert_held(&request->i915->drm.struct_mutex);
> @@ -307,10 +309,11 @@ void i915_request_retire_upto(struct i915_request *rq)
>   	struct intel_ring *ring = rq->ring;
>   	struct i915_request *tmp;
>   
> -	GEM_TRACE("%s fence %llx:%lld, global=%d, current %d\n",
> +	GEM_TRACE("%s fence %llx:%lld, global=%d, current %d:%d\n",
>   		  rq->engine->name,
>   		  rq->fence.context, rq->fence.seqno,
>   		  rq->global_seqno,
> +		  hwsp_seqno(rq),
>   		  intel_engine_get_seqno(rq->engine));
>   
>   	lockdep_assert_held(&rq->i915->drm.struct_mutex);
> @@ -348,10 +351,11 @@ void __i915_request_submit(struct i915_request *request)
>   	struct intel_engine_cs *engine = request->engine;
>   	u32 seqno;
>   
> -	GEM_TRACE("%s fence %llx:%lld -> global=%d, current %d\n",
> +	GEM_TRACE("%s fence %llx:%lld -> global=%d, current %d:%d\n",
>   		  engine->name,
>   		  request->fence.context, request->fence.seqno,
>   		  engine->timeline.seqno + 1,
> +		  hwsp_seqno(request),
>   		  intel_engine_get_seqno(engine));
>   
>   	GEM_BUG_ON(!irqs_disabled());
> @@ -398,10 +402,11 @@ void __i915_request_unsubmit(struct i915_request *request)
>   {
>   	struct intel_engine_cs *engine = request->engine;
>   
> -	GEM_TRACE("%s fence %llx:%lld <- global=%d, current %d\n",
> +	GEM_TRACE("%s fence %llx:%lld <- global=%d, current %d:%d\n",
>   		  engine->name,
>   		  request->fence.context, request->fence.seqno,
>   		  request->global_seqno,
> +		  hwsp_seqno(request),
>   		  intel_engine_get_seqno(engine));
>   
>   	GEM_BUG_ON(!irqs_disabled());
> @@ -609,6 +614,7 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx)
>   	rq->ring = ce->ring;
>   	rq->timeline = ce->ring->timeline;
>   	GEM_BUG_ON(rq->timeline == &engine->timeline);
> +	rq->hwsp_seqno = &engine->status_page.addr[I915_GEM_HWS_INDEX];
>   
>   	spin_lock_init(&rq->lock);
>   	dma_fence_init(&rq->fence,
> diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h
> index d014b0605445..4dd22dadf5ce 100644
> --- a/drivers/gpu/drm/i915/i915_request.h
> +++ b/drivers/gpu/drm/i915/i915_request.h
> @@ -130,6 +130,13 @@ struct i915_request {
>   	struct i915_sched_node sched;
>   	struct i915_dependency dep;
>   
> +	/*
> +	 * A convenience pointer to the current breadcrumb value stored in
> +	 * the HW status page (or our timeline's local equivalent). The full
> +	 * path would be rq->hw_context->ring->timeline->hwsp_seqno.
> +	 */
> +	const u32 *hwsp_seqno;
> +
>   	/**
>   	 * GEM sequence number associated with this request on the
>   	 * global execution timeline. It is zero when the request is not
> @@ -280,11 +287,6 @@ long i915_request_wait(struct i915_request *rq,
>   #define I915_WAIT_ALL		BIT(3) /* used by i915_gem_object_wait() */
>   #define I915_WAIT_FOR_IDLE_BOOST BIT(4)
>   
> -static inline bool intel_engine_has_started(struct intel_engine_cs *engine,
> -					    u32 seqno);
> -static inline bool intel_engine_has_completed(struct intel_engine_cs *engine,
> -					      u32 seqno);
> -
>   /**
>    * Returns true if seq1 is later than seq2.
>    */
> @@ -293,6 +295,24 @@ static inline bool i915_seqno_passed(u32 seq1, u32 seq2)
>   	return (s32)(seq1 - seq2) >= 0;
>   }
>   
> +/**
> + * hwsp_seqno - the current breadcrumb value in the HW status page
> + * @rq: the request, to chase the relevant HW status page
> + *
> + * The emphasis in naming here is that hwsp_seqno() is not a property of the
> + * request, but an indication of the current HW state (associated with this
> + * request). Its value will change as the GPU executes more requests.
> + *
> + * Returns the current breadcrumb value in the associated HW status page (or
> + * the local timeline's equivalent) for this request. The request itself
> + * has the associated breadcrumb value of rq->fence.seqno, when the HW
> + * status page has that breadcrumb or later, this request is complete.
> + */
> +static inline u32 hwsp_seqno(const struct i915_request *rq)
> +{
> +	return READ_ONCE(*rq->hwsp_seqno);
> +}
> +
>   /**
>    * i915_request_started - check if the request has begun being executed
>    * @rq: the request
> @@ -310,14 +330,14 @@ static inline bool i915_request_started(const struct i915_request *rq)
>   	if (!seqno) /* not yet submitted to HW */
>   		return false;
>   
> -	return intel_engine_has_started(rq->engine, seqno);
> +	return i915_seqno_passed(hwsp_seqno(rq), seqno - 1);
>   }
>   
>   static inline bool
>   __i915_request_completed(const struct i915_request *rq, u32 seqno)
>   {
>   	GEM_BUG_ON(!seqno);
> -	return intel_engine_has_completed(rq->engine, seqno) &&
> +	return i915_seqno_passed(hwsp_seqno(rq), seqno) &&
>   		seqno == i915_request_global_seqno(rq);
>   }
>   
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index edb26f69d864..4e942c403333 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -444,11 +444,12 @@ static void execlists_submit_ports(struct intel_engine_cs *engine)
>   			desc = execlists_update_context(rq);
>   			GEM_DEBUG_EXEC(port[n].context_id = upper_32_bits(desc));
>   
> -			GEM_TRACE("%s in[%d]:  ctx=%d.%d, global=%d (fence %llx:%lld) (current %d), prio=%d\n",
> +			GEM_TRACE("%s in[%d]:  ctx=%d.%d, global=%d (fence %llx:%lld) (current %d:%d), prio=%d\n",
>   				  engine->name, n,
>   				  port[n].context_id, count,
>   				  rq->global_seqno,
>   				  rq->fence.context, rq->fence.seqno,
> +				  hwsp_seqno(rq),
>   				  intel_engine_get_seqno(engine),
>   				  rq_prio(rq));
>   		} else {
> @@ -737,11 +738,12 @@ execlists_cancel_port_requests(struct intel_engine_execlists * const execlists)
>   	while (num_ports-- && port_isset(port)) {
>   		struct i915_request *rq = port_request(port);
>   
> -		GEM_TRACE("%s:port%u global=%d (fence %llx:%lld), (current %d)\n",
> +		GEM_TRACE("%s:port%u global=%d (fence %llx:%lld), (current %d:%d)\n",
>   			  rq->engine->name,
>   			  (unsigned int)(port - execlists->port),
>   			  rq->global_seqno,
>   			  rq->fence.context, rq->fence.seqno,
> +			  hwsp_seqno(rq),
>   			  intel_engine_get_seqno(rq->engine));
>   
>   		GEM_BUG_ON(!execlists->active);
> @@ -965,12 +967,13 @@ static void process_csb(struct intel_engine_cs *engine)
>   						EXECLISTS_ACTIVE_USER));
>   
>   		rq = port_unpack(port, &count);
> -		GEM_TRACE("%s out[0]: ctx=%d.%d, global=%d (fence %llx:%lld) (current %d), prio=%d\n",
> +		GEM_TRACE("%s out[0]: ctx=%d.%d, global=%d (fence %llx:%lld) (current %d:%d), prio=%d\n",
>   			  engine->name,
>   			  port->context_id, count,
>   			  rq ? rq->global_seqno : 0,
>   			  rq ? rq->fence.context : 0,
>   			  rq ? rq->fence.seqno : 0,
> +			  rq ? hwsp_seqno(rq) : 0,
>   			  intel_engine_get_seqno(engine),
>   			  rq ? rq_prio(rq) : 0);
>   
> 

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 16/23] drm/i915: Allocate a status page for each timeline
  2019-01-17 14:34 ` [PATCH 16/23] drm/i915: Allocate a status page for each timeline Chris Wilson
@ 2019-01-18 11:19   ` Tvrtko Ursulin
  0 siblings, 0 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-18 11:19 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> Allocate a page for use as a status page by a group of timelines, as we
> only need a dword of storage for each (rounded up to the cacheline for
> safety) we can pack multiple timelines into the same page. Each timeline
> will then be able to track its own HW seqno.
> 
> v2: Reuse the common per-engine HWSP for the solitary ringbuffer
> timeline, so that we do not have to emit (using per-gen specialised
> vfuncs) the breadcrumb into the distinct timeline HWSP and instead can
> keep on using the common MI_STORE_DWORD_INDEX. However, to maintain the
> sleight-of-hand for the global/per-context seqno switchover, we will
> store both temporarily (and so use a custom offset for the shared timeline
> HWSP until the switch over).
> 
> v3: Keep things simple and allocate a page for each timeline, page
> sharing comes next.
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_timeline.c          | 106 ++++-
>   drivers/gpu/drm/i915/i915_timeline.h          |  21 +-
>   drivers/gpu/drm/i915/intel_engine_cs.c        |  64 +--
>   drivers/gpu/drm/i915/intel_lrc.c              |  22 +-
>   drivers/gpu/drm/i915/intel_ringbuffer.c       |  10 +-
>   drivers/gpu/drm/i915/intel_ringbuffer.h       |   6 +-
>   .../drm/i915/selftests/i915_live_selftests.h  |   1 +
>   .../drm/i915/selftests/i915_mock_selftests.h  |   2 +-
>   .../gpu/drm/i915/selftests/i915_timeline.c    | 373 +++++++++++++++++-
>   drivers/gpu/drm/i915/selftests/mock_engine.c  |  17 +-
>   10 files changed, 571 insertions(+), 51 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
> index 84550f17d3df..380f4d25fb89 100644
> --- a/drivers/gpu/drm/i915/i915_timeline.c
> +++ b/drivers/gpu/drm/i915/i915_timeline.c
> @@ -9,11 +9,38 @@
>   #include "i915_timeline.h"
>   #include "i915_syncmap.h"
>   
> -void i915_timeline_init(struct drm_i915_private *i915,
> -			struct i915_timeline *timeline,
> -			const char *name)
> +static int hwsp_alloc(struct i915_timeline *timeline)
> +{
> +	struct drm_i915_private *i915 = timeline->i915;
> +	struct drm_i915_gem_object *bo;

Normally we use obj in the kernel, but I guess this is also temporary code.

> +	struct i915_vma *vma;
> +
> +	bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
> +	if (IS_ERR(bo))
> +		return PTR_ERR(bo);
> +
> +	i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
> +
> +	vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
> +	if (IS_ERR(vma)) {
> +		i915_gem_object_put(bo);
> +		return PTR_ERR(vma);
> +	}
> +
> +	timeline->hwsp_ggtt = vma;
> +	timeline->hwsp_offset = 0;
> +
> +	return 0;
> +}
> +
> +int i915_timeline_init(struct drm_i915_private *i915,
> +		       struct i915_timeline *timeline,
> +		       const char *name,
> +		       struct i915_vma *global_hwsp)
>   {
>   	struct i915_gt_timelines *gt = &i915->gt.timelines;
> +	void *vaddr;
> +	int err;
>   
>   	/*
>   	 * Ideally we want a set of engines on a single leaf as we expect
> @@ -25,10 +52,27 @@ void i915_timeline_init(struct drm_i915_private *i915,
>   
>   	timeline->i915 = i915;
>   	timeline->name = name;
> +	timeline->pin_count = 0;
> +
> +	if (global_hwsp) {
> +		timeline->hwsp_ggtt = i915_vma_get(global_hwsp);
> +		timeline->hwsp_offset = I915_GEM_HWS_SEQNO_ADDR;
> +	} else {
> +		err = hwsp_alloc(timeline);
> +		if (err)
> +			return err;
> +	}
>   
> -	mutex_lock(&gt->mutex);
> -	list_add(&timeline->link, &gt->list);
> -	mutex_unlock(&gt->mutex);
> +	vaddr = i915_gem_object_pin_map(timeline->hwsp_ggtt->obj, I915_MAP_WB);
> +	if (IS_ERR(vaddr)) {
> +		i915_vma_put(timeline->hwsp_ggtt);
> +		return PTR_ERR(vaddr);
> +	}
> +
> +	timeline->hwsp_seqno =
> +		memset(vaddr + timeline->hwsp_offset,
> +		       0,
> +		       sizeof(*timeline->hwsp_seqno));

Would it be worth zeroing the object after allocation so a) here we can 
assert our slot is unused, and b) if we decide to hexdump the whole page 
we get more useful output?

>   
>   	/* Called during early_init before we know how many engines there are */
>   
> @@ -40,6 +84,12 @@ void i915_timeline_init(struct drm_i915_private *i915,
>   	INIT_LIST_HEAD(&timeline->requests);
>   
>   	i915_syncmap_init(&timeline->sync);
> +
> +	mutex_lock(&gt->mutex);
> +	list_add(&timeline->link, &gt->list);
> +	mutex_unlock(&gt->mutex);
> +
> +	return 0;
>   }
>   
>   void i915_timelines_init(struct drm_i915_private *i915)
> @@ -85,6 +135,7 @@ void i915_timeline_fini(struct i915_timeline *timeline)
>   {
>   	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
>   
> +	GEM_BUG_ON(timeline->pin_count);
>   	GEM_BUG_ON(!list_empty(&timeline->requests));
>   
>   	i915_syncmap_free(&timeline->sync);
> @@ -92,23 +143,62 @@ void i915_timeline_fini(struct i915_timeline *timeline)
>   	mutex_lock(&gt->mutex);
>   	list_del(&timeline->link);
>   	mutex_unlock(&gt->mutex);
> +
> +	i915_gem_object_unpin_map(timeline->hwsp_ggtt->obj);
> +	i915_vma_put(timeline->hwsp_ggtt);
>   }
>   
>   struct i915_timeline *
> -i915_timeline_create(struct drm_i915_private *i915, const char *name)
> +i915_timeline_create(struct drm_i915_private *i915,
> +		     const char *name,
> +		     struct i915_vma *global_hwsp)
>   {
>   	struct i915_timeline *timeline;
> +	int err;
>   
>   	timeline = kzalloc(sizeof(*timeline), GFP_KERNEL);
>   	if (!timeline)
>   		return ERR_PTR(-ENOMEM);
>   
> -	i915_timeline_init(i915, timeline, name);
> +	err = i915_timeline_init(i915, timeline, name, global_hwsp);
> +	if (err) {
> +		kfree(timeline);
> +		return ERR_PTR(err);
> +	}
> +
>   	kref_init(&timeline->kref);
>   
>   	return timeline;
>   }
>   
> +int i915_timeline_pin(struct i915_timeline *tl)
> +{
> +	int err;
> +
> +	if (tl->pin_count++)
> +		return 0;
> +	GEM_BUG_ON(!tl->pin_count);
> +
> +	err = i915_vma_pin(tl->hwsp_ggtt, 0, 0, PIN_GLOBAL | PIN_HIGH);

Btw.. what are the considerations for timeline hwsp in ggtt vs in ppgtt? 
Latter would mean shared pages between all contexts with a shared ppgtt, 
so more memory use, but also more isolation.

> +	if (err)
> +		goto unpin;
> +
> +	return 0;
> +
> +unpin:
> +	tl->pin_count = 0;
> +	return err;
> +}
> +
> +void i915_timeline_unpin(struct i915_timeline *tl)
> +{
> +	GEM_BUG_ON(!tl->pin_count);
> +	if (--tl->pin_count)
> +		return;
> +
> +	__i915_vma_unpin(tl->hwsp_ggtt);
> +}
> +
>   void __i915_timeline_free(struct kref *kref)
>   {
>   	struct i915_timeline *timeline =
> diff --git a/drivers/gpu/drm/i915/i915_timeline.h b/drivers/gpu/drm/i915/i915_timeline.h
> index 87ad2dd31c20..0c3739d53d79 100644
> --- a/drivers/gpu/drm/i915/i915_timeline.h
> +++ b/drivers/gpu/drm/i915/i915_timeline.h
> @@ -32,6 +32,8 @@
>   #include "i915_syncmap.h"
>   #include "i915_utils.h"
>   
> +struct i915_vma;
> +
>   struct i915_timeline {
>   	u64 fence_context;
>   	u32 seqno;
> @@ -40,6 +42,11 @@ struct i915_timeline {
>   #define TIMELINE_CLIENT 0 /* default subclass */
>   #define TIMELINE_ENGINE 1
>   
> +	unsigned int pin_count;
> +	const u32 *hwsp_seqno;
> +	struct i915_vma *hwsp_ggtt;
> +	u32 hwsp_offset;

One bikeshed could be grouping above three in a struct eg. 
timeline->hwsp.offset.

> +
>   	/**
>   	 * List of breadcrumbs associated with GPU requests currently
>   	 * outstanding.
> @@ -71,9 +78,10 @@ struct i915_timeline {
>   	struct kref kref;
>   };
>   
> -void i915_timeline_init(struct drm_i915_private *i915,
> -			struct i915_timeline *tl,
> -			const char *name);
> +int i915_timeline_init(struct drm_i915_private *i915,
> +		       struct i915_timeline *tl,
> +		       const char *name,
> +		       struct i915_vma *hwsp);
>   void i915_timeline_fini(struct i915_timeline *tl);
>   
>   static inline void
> @@ -96,7 +104,9 @@ i915_timeline_set_subclass(struct i915_timeline *timeline,
>   }
>   
>   struct i915_timeline *
> -i915_timeline_create(struct drm_i915_private *i915, const char *name);
> +i915_timeline_create(struct drm_i915_private *i915,
> +		     const char *name,
> +		     struct i915_vma *global_hwsp);
>   
>   static inline struct i915_timeline *
>   i915_timeline_get(struct i915_timeline *timeline)
> @@ -135,6 +145,9 @@ static inline bool i915_timeline_sync_is_later(struct i915_timeline *tl,
>   	return __i915_timeline_sync_is_later(tl, fence->context, fence->seqno);
>   }
>   
> +int i915_timeline_pin(struct i915_timeline *tl);
> +void i915_timeline_unpin(struct i915_timeline *tl);
> +
>   void i915_timelines_init(struct drm_i915_private *i915);
>   void i915_timelines_park(struct drm_i915_private *i915);
>   void i915_timelines_fini(struct drm_i915_private *i915);
> diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
> index 4b4b7358c482..c850d131d8c3 100644
> --- a/drivers/gpu/drm/i915/intel_engine_cs.c
> +++ b/drivers/gpu/drm/i915/intel_engine_cs.c
> @@ -484,26 +484,6 @@ static void intel_engine_init_execlist(struct intel_engine_cs *engine)
>   	execlists->queue = RB_ROOT_CACHED;
>   }
>   
> -/**
> - * intel_engines_setup_common - setup engine state not requiring hw access
> - * @engine: Engine to setup.
> - *
> - * Initializes @engine@ structure members shared between legacy and execlists
> - * submission modes which do not require hardware access.
> - *
> - * Typically done early in the submission mode specific engine setup stage.
> - */
> -void intel_engine_setup_common(struct intel_engine_cs *engine)
> -{
> -	i915_timeline_init(engine->i915, &engine->timeline, engine->name);
> -	i915_timeline_set_subclass(&engine->timeline, TIMELINE_ENGINE);
> -
> -	intel_engine_init_execlist(engine);
> -	intel_engine_init_hangcheck(engine);
> -	intel_engine_init_batch_pool(engine);
> -	intel_engine_init_cmd_parser(engine);
> -}
> -
>   static void cleanup_status_page(struct intel_engine_cs *engine)
>   {
>   	struct i915_vma *vma;
> @@ -601,6 +581,44 @@ static int init_status_page(struct intel_engine_cs *engine)
>   	return ret;
>   }
>   
> +/**
> + * intel_engines_setup_common - setup engine state not requiring hw access
> + * @engine: Engine to setup.
> + *
> + * Initializes @engine@ structure members shared between legacy and execlists
> + * submission modes which do not require hardware access.
> + *
> + * Typically done early in the submission mode specific engine setup stage.
> + */
> +int intel_engine_setup_common(struct intel_engine_cs *engine)
> +{
> +	int err;
> +
> +	err = init_status_page(engine);
> +	if (err)
> +		return err;

Bummer, comments reminds the setup/init split was supposed to mean no hw 
access from the setup phase. Is it too late from init?

> +
> +	err = i915_timeline_init(engine->i915,
> +				 &engine->timeline,
> +				 engine->name,
> +				 engine->status_page.vma);
> +	if (err)
> +		goto err_hwsp;
> +
> +	i915_timeline_set_subclass(&engine->timeline, TIMELINE_ENGINE);
> +
> +	intel_engine_init_execlist(engine);
> +	intel_engine_init_hangcheck(engine);
> +	intel_engine_init_batch_pool(engine);
> +	intel_engine_init_cmd_parser(engine);
> +
> +	return 0;
> +
> +err_hwsp:
> +	cleanup_status_page(engine);
> +	return err;
> +}
> +
>   static void __intel_context_unpin(struct i915_gem_context *ctx,
>   				  struct intel_engine_cs *engine)
>   {
> @@ -653,14 +671,8 @@ int intel_engine_init_common(struct intel_engine_cs *engine)
>   	if (ret)
>   		goto err_unpin_preempt;
>   
> -	ret = init_status_page(engine);
> -	if (ret)
> -		goto err_breadcrumbs;
> -
>   	return 0;
>   
> -err_breadcrumbs:
> -	intel_engine_fini_breadcrumbs(engine);
>   err_unpin_preempt:
>   	if (i915->preempt_context)
>   		__intel_context_unpin(i915->preempt_context, engine);
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index 4e942c403333..a624e644fbd7 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -2187,10 +2187,14 @@ logical_ring_default_irqs(struct intel_engine_cs *engine)
>   	engine->irq_keep_mask = GT_CONTEXT_SWITCH_INTERRUPT << shift;
>   }
>   
> -static void
> +static int
>   logical_ring_setup(struct intel_engine_cs *engine)
>   {
> -	intel_engine_setup_common(engine);
> +	int err;
> +
> +	err = intel_engine_setup_common(engine);
> +	if (err)
> +		return err;
>   
>   	/* Intentionally left blank. */
>   	engine->buffer = NULL;
> @@ -2200,6 +2204,8 @@ logical_ring_setup(struct intel_engine_cs *engine)
>   
>   	logical_ring_default_vfuncs(engine);
>   	logical_ring_default_irqs(engine);
> +
> +	return 0;
>   }
>   
>   static int logical_ring_init(struct intel_engine_cs *engine)
> @@ -2248,7 +2254,9 @@ int logical_render_ring_init(struct intel_engine_cs *engine)
>   {
>   	int ret;
>   
> -	logical_ring_setup(engine);
> +	ret = logical_ring_setup(engine);
> +	if (ret)
> +		return ret;
>   
>   	/* Override some for render ring. */
>   	engine->init_context = gen8_init_rcs_context;
> @@ -2278,7 +2286,11 @@ int logical_render_ring_init(struct intel_engine_cs *engine)
>   
>   int logical_xcs_ring_init(struct intel_engine_cs *engine)
>   {
> -	logical_ring_setup(engine);
> +	int err;
> +
> +	err = logical_ring_setup(engine);
> +	if (err)
> +		return err;
>   
>   	return logical_ring_init(engine);
>   }
> @@ -2612,7 +2624,7 @@ static int execlists_context_deferred_alloc(struct i915_gem_context *ctx,
>   		goto error_deref_obj;
>   	}
>   
> -	timeline = i915_timeline_create(ctx->i915, ctx->name);
> +	timeline = i915_timeline_create(ctx->i915, ctx->name, NULL);
>   	if (IS_ERR(timeline)) {
>   		ret = PTR_ERR(timeline);
>   		goto error_deref_obj;
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index d72012b42f20..5887304bc3ae 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -1539,9 +1539,13 @@ static int intel_init_ring_buffer(struct intel_engine_cs *engine)
>   	struct intel_ring *ring;
>   	int err;
>   
> -	intel_engine_setup_common(engine);
> +	err = intel_engine_setup_common(engine);
> +	if (err)
> +		return err;
>   
> -	timeline = i915_timeline_create(engine->i915, engine->name);
> +	timeline = i915_timeline_create(engine->i915,
> +					engine->name,
> +					engine->status_page.vma);
>   	if (IS_ERR(timeline)) {
>   		err = PTR_ERR(timeline);
>   		goto err;
> @@ -1565,6 +1569,8 @@ static int intel_init_ring_buffer(struct intel_engine_cs *engine)
>   	if (err)
>   		goto err_unpin;
>   
> +	GEM_BUG_ON(ring->timeline->hwsp_ggtt != engine->status_page.vma);
> +
>   	return 0;
>   
>   err_unpin:
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
> index 9972c9016445..5c20b41b6a9b 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.h
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
> @@ -716,7 +716,9 @@ intel_write_status_page(struct intel_engine_cs *engine, int reg, u32 value)
>   #define I915_GEM_HWS_INDEX_ADDR (I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
>   #define I915_GEM_HWS_PREEMPT_INDEX	0x32
>   #define I915_GEM_HWS_PREEMPT_ADDR (I915_GEM_HWS_PREEMPT_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
> -#define I915_GEM_HWS_SCRATCH_INDEX	0x40
> +#define I915_GEM_HWS_SEQNO		0x40
> +#define I915_GEM_HWS_SEQNO_ADDR (I915_GEM_HWS_SEQNO << MI_STORE_DWORD_INDEX_SHIFT)
> +#define I915_GEM_HWS_SCRATCH_INDEX	0x80
>   #define I915_GEM_HWS_SCRATCH_ADDR (I915_GEM_HWS_SCRATCH_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
>   
>   #define I915_HWS_CSB_BUF0_INDEX		0x10
> @@ -822,7 +824,7 @@ intel_ring_set_tail(struct intel_ring *ring, unsigned int tail)
>   
>   void intel_engine_write_global_seqno(struct intel_engine_cs *engine, u32 seqno);
>   
> -void intel_engine_setup_common(struct intel_engine_cs *engine);
> +int intel_engine_setup_common(struct intel_engine_cs *engine);
>   int intel_engine_init_common(struct intel_engine_cs *engine);
>   void intel_engine_cleanup_common(struct intel_engine_cs *engine);
>   
> diff --git a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
> index a15713cae3b3..76b4f87fc853 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
> +++ b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
> @@ -13,6 +13,7 @@ selftest(sanitycheck, i915_live_sanitycheck) /* keep first (igt selfcheck) */
>   selftest(uncore, intel_uncore_live_selftests)
>   selftest(workarounds, intel_workarounds_live_selftests)
>   selftest(requests, i915_request_live_selftests)
> +selftest(timelines, i915_timeline_live_selftests)
>   selftest(objects, i915_gem_object_live_selftests)
>   selftest(dmabuf, i915_gem_dmabuf_live_selftests)
>   selftest(coherency, i915_gem_coherency_live_selftests)
> diff --git a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
> index 1b70208eeea7..4a83a1c6c406 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
> +++ b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h
> @@ -16,7 +16,7 @@ selftest(syncmap, i915_syncmap_mock_selftests)
>   selftest(uncore, intel_uncore_mock_selftests)
>   selftest(engine, intel_engine_cs_mock_selftests)
>   selftest(breadcrumbs, intel_breadcrumbs_mock_selftests)
> -selftest(timelines, i915_gem_timeline_mock_selftests)
> +selftest(timelines, i915_timeline_mock_selftests)
>   selftest(requests, i915_request_mock_selftests)
>   selftest(objects, i915_gem_object_mock_selftests)
>   selftest(dmabuf, i915_gem_dmabuf_mock_selftests)
> diff --git a/drivers/gpu/drm/i915/selftests/i915_timeline.c b/drivers/gpu/drm/i915/selftests/i915_timeline.c
> index 19f1c6a5c8fb..d13779808200 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_timeline.c
> +++ b/drivers/gpu/drm/i915/selftests/i915_timeline.c
> @@ -256,7 +256,7 @@ static int bench_sync(void *arg)
>   	return 0;
>   }
>   
> -int i915_gem_timeline_mock_selftests(void)
> +int i915_timeline_mock_selftests(void)
>   {
>   	static const struct i915_subtest tests[] = {
>   		SUBTEST(igt_sync),
> @@ -265,3 +265,374 @@ int i915_gem_timeline_mock_selftests(void)
>   
>   	return i915_subtests(tests, NULL);
>   }
> +
> +static int live_hwsp_engine(void *arg)
> +{
> +#define NUM_TIMELINES 4096
> +	struct drm_i915_private *i915 = arg;
> +	struct i915_timeline **timelines;
> +	struct intel_engine_cs *engine;
> +	enum intel_engine_id id;
> +	intel_wakeref_t wakeref;
> +	unsigned long count, n;
> +	int err = 0;
> +
> +	/*
> +	 * Create a bunch of timelines and check we can write
> +	 * independently to each of their breadcrumb slots.
> +	 */
> +
> +	timelines = kvmalloc_array(NUM_TIMELINES * I915_NUM_ENGINES,
> +				   sizeof(*timelines),
> +				   GFP_KERNEL);
> +	if (!timelines)
> +		return -ENOMEM;
> +
> +	mutex_lock(&i915->drm.struct_mutex);
> +	wakeref = intel_runtime_pm_get(i915);

Nitpick - we normally do this in reverse order.

> +
> +	count = 0;
> +	for_each_engine(engine, i915, id) {
> +		if (!intel_engine_can_store_dword(engine))
> +			continue;
> +
> +		for (n = 0; n < NUM_TIMELINES; n++) {
> +			struct i915_timeline *tl;
> +			struct i915_request *rq;
> +			u32 addr;
> +			u32 *cs;
> +
> +			tl = i915_timeline_create(i915, "live", NULL);
> +			if (IS_ERR(tl)) {
> +				err = PTR_ERR(tl);
> +				goto out;
> +			}
> +
> +			if (*tl->hwsp_seqno) {
> +				pr_err("Timeline %lu created with non-zero breadcrumb, found %x\n",
> +				       count, *tl->hwsp_seqno);
> +				err = -EINVAL;
> +				i915_timeline_put(tl);
> +				goto out;
> +			}
> +
> +			err = i915_timeline_pin(tl);
> +			if (err) {
> +				i915_timeline_put(tl);

Wanna add some pr_err's around these parts for easier debug? 
Hyphotetical I know..

> +				goto out;
> +			}
> +
> +			rq = i915_request_alloc(engine, i915->kernel_context);
> +			if (IS_ERR(rq)) {
> +				i915_timeline_unpin(tl);
> +				i915_timeline_put(tl);
> +				err = PTR_ERR(rq);
> +				goto out;
> +			}
> +
> +			cs = intel_ring_begin(rq, 4);
> +			if (IS_ERR(cs)) {
> +				i915_request_add(rq);

Can't we use i915_request_skip here? Won't we execute random garbage if 
ring wrapped? Ah no because no advance.

> +				i915_timeline_unpin(tl);
> +				i915_timeline_put(tl);
> +				err = PTR_ERR(cs);
> +				goto out;
> +			}
> +
> +			addr = i915_ggtt_offset(tl->hwsp_ggtt) + tl->hwsp_offset;
> +
> +			if (INTEL_GEN(i915) >= 8) {
> +				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
> +				*cs++ = addr;
> +				*cs++ = 0;
> +				*cs++ = count;
> +			} else if (INTEL_GEN(i915) >= 4) {
> +				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
> +				*cs++ = 0;
> +				*cs++ = addr;
> +				*cs++ = count;
> +			} else {
> +				*cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
> +				*cs++ = addr;
> +				*cs++ = count;
> +				*cs++ = MI_NOOP;
> +			}

Note to self, see if at some later point we can consolidate store dword 
emission.

> +			intel_ring_advance(rq, cs);
> +
> +			i915_request_add(rq);
> +			i915_timeline_unpin(tl);
> +
> +			timelines[count++] = tl;
> +		}
> +	}
> +
> +	err = i915_gem_wait_for_idle(i915, I915_WAIT_LOCKED, MAX_SCHEDULE_TIMEOUT);

Use selftests timeout here? Or too short? Hm it would mean changing the 
loop slightly to test until timeout.. but that would be in the spirit of 
selftests timeout, no?

> +
> +out:
> +	for (n = 0; n < count; n++) {
> +		struct i915_timeline *tl = timelines[n];
> +
> +		if (!err && *tl->hwsp_seqno != n) {
> +			pr_err("Invalid seqno stored in timeline %lu, found 0x%x\n",

At least you added 0x prefix to avoid "Invalid seqno stored in timeline 
5, found 5\n"! ;) But same base would be even better. :)

> +			       n, *tl->hwsp_seqno);
> +			err = -EINVAL;
> +		}
> +		i915_timeline_put(tl);
> +	}
> +
> +	intel_runtime_pm_put(i915, wakeref);
> +	mutex_unlock(&i915->drm.struct_mutex);
> +
> +	kvfree(timelines);
> +
> +	return err;
> +#undef NUM_TIMELINES
> +}
> +
> +static int live_hwsp_alternate(void *arg)
> +{
> +#define NUM_TIMELINES 4096
> +	struct drm_i915_private *i915 = arg;
> +	struct i915_timeline **timelines;
> +	struct intel_engine_cs *engine;
> +	enum intel_engine_id id;
> +	intel_wakeref_t wakeref;
> +	unsigned long count, n;
> +	int err = 0;
> +
> +	/*
> +	 * Create a bunch of timelines and check we can write
> +	 * independently to each of their breadcrumb slots with adjacent
> +	 * engines.
> +	 */
> +
> +	timelines = kvmalloc_array(NUM_TIMELINES * I915_NUM_ENGINES,
> +				   sizeof(*timelines),
> +				   GFP_KERNEL);
> +	if (!timelines)
> +		return -ENOMEM;
> +
> +	mutex_lock(&i915->drm.struct_mutex);
> +	wakeref = intel_runtime_pm_get(i915);
> +
> +	count = 0;
> +	for (n = 0; n < NUM_TIMELINES; n++) {
> +		for_each_engine(engine, i915, id) {
> +			struct i915_timeline *tl;
> +			struct i915_request *rq;
> +			u32 addr;
> +			u32 *cs;
> +
> +			if (!intel_engine_can_store_dword(engine))
> +				continue;
> +
> +			tl = i915_timeline_create(i915, "live", NULL);
> +			if (IS_ERR(tl)) {
> +				err = PTR_ERR(tl);
> +				goto out;
> +			}
> +
> +			if (*tl->hwsp_seqno) {
> +				pr_err("Timeline %lu created with non-zero breadcrumb, found %x\n",
> +				       count, *tl->hwsp_seqno);
> +				err = -EINVAL;
> +				i915_timeline_put(tl);
> +				goto out;
> +			}
> +
> +			err = i915_timeline_pin(tl);
> +			if (err) {
> +				i915_timeline_put(tl);
> +				goto out;
> +			}
> +
> +			rq = i915_request_alloc(engine, i915->kernel_context);
> +			if (IS_ERR(rq)) {
> +				i915_timeline_unpin(tl);
> +				i915_timeline_put(tl);
> +				err = PTR_ERR(rq);
> +				goto out;
> +			}
> +
> +			cs = intel_ring_begin(rq, 4);
> +			if (IS_ERR(cs)) {
> +				i915_request_add(rq);
> +				i915_timeline_unpin(tl);
> +				i915_timeline_put(tl);
> +				err = PTR_ERR(cs);
> +				goto out;
> +			}
> +
> +			addr = i915_ggtt_offset(tl->hwsp_ggtt) + tl->hwsp_offset;
> +
> +			if (INTEL_GEN(i915) >= 8) {
> +				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
> +				*cs++ = addr;
> +				*cs++ = 0;
> +				*cs++ = count;
> +			} else if (INTEL_GEN(i915) >= 4) {
> +				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
> +				*cs++ = 0;
> +				*cs++ = addr;
> +				*cs++ = count;
> +			} else {
> +				*cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
> +				*cs++ = addr;
> +				*cs++ = count;
> +				*cs++ = MI_NOOP;
> +			}

Okay, I am upgrading the "note to self" from above to "please 
consolidate" store dword emission at least locally.

Maybe even the whole loop body could be common?

	err = tl_emit_rq(&timelines[count], engine, count);
	if (err)
		goto out;
	
	count++;
?

> +			intel_ring_advance(rq, cs);
> +
> +			i915_request_add(rq);
> +			i915_timeline_unpin(tl);
> +
> +			timelines[count++] = tl;
> +		}
> +	}
> +
> +	err = i915_gem_wait_for_idle(i915, I915_WAIT_LOCKED, MAX_SCHEDULE_TIMEOUT);
> +
> +out:
> +	for (n = 0; n < count; n++) {
> +		struct i915_timeline *tl = timelines[n];
> +
> +		if (!err && *tl->hwsp_seqno != n) {
> +			pr_err("Invalid seqno stored in timeline %lu, found 0x%x\n",
> +			       n, *tl->hwsp_seqno);
> +			err = -EINVAL;
> +		}
> +		i915_timeline_put(tl);
> +	}
> +
> +	intel_runtime_pm_put(i915, wakeref);
> +	mutex_unlock(&i915->drm.struct_mutex);
> +
> +	kvfree(timelines);
> +
> +	return err;
> +#undef NUM_TIMELINES
> +}
> +
> +static int live_hwsp_recycle(void *arg)
> +{
> +	struct drm_i915_private *i915 = arg;
> +	struct intel_engine_cs *engine;
> +	enum intel_engine_id id;
> +	intel_wakeref_t wakeref;
> +	unsigned long count;
> +	int err = 0;
> +
> +	/*
> +	 * Check seqno writes into one timeline at a time. We expect to
> +	 * recycle the breadcrumb slot between iterations and neither
> +	 * want to confuse ourselves or the GPU.
> +	 */
> +
> +	mutex_lock(&i915->drm.struct_mutex);
> +	wakeref = intel_runtime_pm_get(i915);
> +
> +	count = 0;
> +	for_each_engine(engine, i915, id) {
> +		IGT_TIMEOUT(end_time);
> +
> +		if (!intel_engine_can_store_dword(engine))
> +			continue;
> +
> +		do {
> +			struct i915_timeline *tl;
> +			struct i915_request *rq;
> +			u32 addr;
> +			u32 *cs;
> +
> +			tl = i915_timeline_create(i915, "live", NULL);
> +			if (IS_ERR(tl)) {
> +				err = PTR_ERR(tl);
> +				goto out;
> +			}
> +
> +			if (*tl->hwsp_seqno) {
> +				pr_err("Timeline %lu created with non-zero breadcrumb, found %x\n",
> +				       count, *tl->hwsp_seqno);
> +				err = -EINVAL;
> +				i915_timeline_put(tl);
> +				goto out;
> +			}
> +
> +			err = i915_timeline_pin(tl);
> +			if (err) {
> +				i915_timeline_put(tl);
> +				goto out;
> +			}
> +
> +			rq = i915_request_alloc(engine, i915->kernel_context);
> +			if (IS_ERR(rq)) {
> +				i915_timeline_unpin(tl);
> +				i915_timeline_put(tl);
> +				err = PTR_ERR(rq);
> +				goto out;
> +			}
> +
> +			cs = intel_ring_begin(rq, 4);
> +			if (IS_ERR(cs)) {
> +				i915_request_add(rq);
> +				i915_timeline_unpin(tl);
> +				i915_timeline_put(tl);
> +				err = PTR_ERR(cs);
> +				goto out;
> +			}
> +
> +			addr = i915_ggtt_offset(tl->hwsp_ggtt) + tl->hwsp_offset;
> +
> +			if (INTEL_GEN(i915) >= 8) {
> +				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
> +				*cs++ = addr;
> +				*cs++ = 0;
> +				*cs++ = count;
> +			} else if (INTEL_GEN(i915) >= 4) {
> +				*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
> +				*cs++ = 0;
> +				*cs++ = addr;
> +				*cs++ = count;
> +			} else {
> +				*cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
> +				*cs++ = addr;
> +				*cs++ = count;
> +				*cs++ = MI_NOOP;
> +			}
> +			intel_ring_advance(rq, cs);
> +
> +			i915_request_add(rq);
> +			i915_timeline_unpin(tl);
> +
> +			i915_request_wait(rq, I915_WAIT_LOCKED, MAX_SCHEDULE_TIMEOUT);

selftests timeout here and check error?

> +			if (*tl->hwsp_seqno != count) {
> +				pr_err("Invalid seqno stored in timeline %lu, found 0x%x\n",
> +				       count, *tl->hwsp_seqno);
> +				err = -EINVAL;
> +			}
> +
> +			i915_timeline_put(tl);
> +			count++;
> +
> +			if (err)
> +				goto out;
> +		} while (!__igt_timeout(end_time, NULL));
> +	}
> +
> +out:
> +	intel_runtime_pm_put(i915, wakeref);
> +	mutex_unlock(&i915->drm.struct_mutex);
> +
> +	return err;
> +}
> +
> +int i915_timeline_live_selftests(struct drm_i915_private *i915)
> +{
> +	static const struct i915_subtest tests[] = {
> +		SUBTEST(live_hwsp_recycle),
> +		SUBTEST(live_hwsp_engine),
> +		SUBTEST(live_hwsp_alternate),
> +	};
> +
> +	return i915_subtests(tests, i915);
> +}
> diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
> index 968a7e139a67..acd27c7e807b 100644
> --- a/drivers/gpu/drm/i915/selftests/mock_engine.c
> +++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
> @@ -34,12 +34,20 @@ static struct intel_ring *mock_ring(struct intel_engine_cs *engine)
>   {
>   	const unsigned long sz = PAGE_SIZE / 2;
>   	struct mock_ring *ring;
> +	int err;
>   
>   	ring = kzalloc(sizeof(*ring) + sz, GFP_KERNEL);
>   	if (!ring)
>   		return NULL;
>   
> -	i915_timeline_init(engine->i915, &ring->timeline, engine->name);
> +	err = i915_timeline_init(engine->i915,
> +				 &ring->timeline,
> +				 engine->name,
> +				 NULL);
> +	if (err) {
> +		kfree(ring);
> +		return NULL;
> +	}
>   
>   	ring->base.size = sz;
>   	ring->base.effective_size = sz;
> @@ -209,7 +217,11 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
>   	engine->base.emit_breadcrumb = mock_emit_breadcrumb;
>   	engine->base.submit_request = mock_submit_request;
>   
> -	i915_timeline_init(i915, &engine->base.timeline, engine->base.name);
> +	if (i915_timeline_init(i915,
> +			       &engine->base.timeline,
> +			       engine->base.name,
> +			       NULL))
> +		goto err_free;
>   	i915_timeline_set_subclass(&engine->base.timeline, TIMELINE_ENGINE);
>   
>   	intel_engine_init_breadcrumbs(&engine->base);
> @@ -227,6 +239,7 @@ struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
>   err_breadcrumbs:
>   	intel_engine_fini_breadcrumbs(&engine->base);
>   	i915_timeline_fini(&engine->base.timeline);
> +err_free:
>   	kfree(engine);
>   	return NULL;
>   }
> 

Regards,

Tvrtko
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 11/23] drm/i915/selftests: Make evict tolerant of foreign objects
  2019-01-17 17:29   ` Tvrtko Ursulin
@ 2019-01-18 11:23     ` Chris Wilson
  0 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-18 11:23 UTC (permalink / raw)
  To: Tvrtko Ursulin, intel-gfx

Quoting Tvrtko Ursulin (2019-01-17 17:29:34)
> 
> On 17/01/2019 14:34, Chris Wilson wrote:
> > The evict selftests presumed that all objects in use had been allocated
> > by itself. This is a dubious claim and so instead of asserting complete
> > control over the object lists, take (temporary) ownership of them
> > instead.
> > 
> > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > ---
> >   .../gpu/drm/i915/selftests/i915_gem_evict.c   | 64 +++++++++++++++----
> >   1 file changed, 53 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> > index fb7df895afeb..c8deb961a020 100644
> > --- a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> > +++ b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
> > @@ -31,30 +31,63 @@
> >   
> >   static int populate_ggtt(struct drm_i915_private *i915)
> >   {
> > -     struct drm_i915_gem_object *obj;
> > +     struct drm_i915_gem_object *obj, *on;
> > +     unsigned long expected_unbound, expected_bound;
> > +     unsigned long unbound, bound, count;
> 
> Minor/optional comment - longs seem like overkill for either filling 
> ggtt with page size objects or for initial state. :)

Force of habit, or just hope for the glorious future.
-Chris
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 13/23] drm/i915: Move list of timelines under its own lock
  2019-01-17 17:54   ` Tvrtko Ursulin
@ 2019-01-18 11:31     ` Chris Wilson
  0 siblings, 0 replies; 50+ messages in thread
From: Chris Wilson @ 2019-01-18 11:31 UTC (permalink / raw)
  To: Tvrtko Ursulin, intel-gfx

Quoting Tvrtko Ursulin (2019-01-17 17:54:38)
> 
> On 17/01/2019 14:34, Chris Wilson wrote:
> > Currently, the list of timelines is serialised by the struct_mutex, but
> > to alleviate difficulties with using that mutex in future, move the
> > list management under its own dedicated mutex.
> > 
> > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > ---
> >   drivers/gpu/drm/i915/i915_drv.h               |  5 +-
> >   drivers/gpu/drm/i915/i915_gem.c               | 89 +++++++++----------
> >   drivers/gpu/drm/i915/i915_reset.c             |  8 +-
> >   drivers/gpu/drm/i915/i915_timeline.c          | 38 ++++++--
> >   drivers/gpu/drm/i915/i915_timeline.h          |  3 +
> >   drivers/gpu/drm/i915/i915_vma.c               |  6 ++
> >   .../gpu/drm/i915/selftests/mock_gem_device.c  |  7 +-
> >   .../gpu/drm/i915/selftests/mock_timeline.c    |  3 +-
> >   8 files changed, 101 insertions(+), 58 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > index 94680b15bed0..3913900600b7 100644
> > --- a/drivers/gpu/drm/i915/i915_drv.h
> > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > @@ -1975,7 +1975,10 @@ struct drm_i915_private {
> >               void (*resume)(struct drm_i915_private *);
> >               void (*cleanup_engine)(struct intel_engine_cs *engine);
> >   
> > -             struct list_head timelines;
> > +             struct i915_gt_timelines {
> > +                     struct mutex mutex; /* protects list, tainted by GPU */
> 
> What does it mean "tainted by GPU"?

Shorthand for we wait under this lock from inside the shrinker; a
reminder about i915_gem_shrinker_taints_mutex() affecting this mutex.

> > +     mutex_lock(&i915->gt.timelines.mutex);
> > +     list_for_each_entry(tl, &i915->gt.timelines.list, link) {
> > +             struct i915_request *rq;
> > +
> > +             rq = i915_gem_active_get_unlocked(&tl->last_request);
> > +             if (!rq)
> > +                     continue;
> > +
> > +             mutex_unlock(&i915->gt.timelines.mutex);
> > +
> > +             /*
> > +              * "Race-to-idle".
> > +              *
> > +              * Switching to the kernel context is often used a synchronous
> > +              * step prior to idling, e.g. in suspend for flushing all
> > +              * current operations to memory before sleeping. These we
> > +              * want to complete as quickly as possible to avoid prolonged
> > +              * stalls, so allow the gpu to boost to maximum clocks.
> > +              */
> > +             if (flags & I915_WAIT_FOR_IDLE_BOOST)
> > +                     gen6_rps_boost(rq, NULL);
> > +
> > +             timeout = i915_request_wait(rq, flags, timeout);
> > +             i915_request_put(rq);
> > +             if (timeout < 0)
> > +                     return timeout;
> > +
> > +             mutex_lock(&i915->gt.timelines.mutex);
> > +
> > +             /* restart after dropping the lock */
> > +             tl = list_entry(&i915->gt.timelines.list, typeof(*tl), link);
> > +     }
> > +     mutex_unlock(&i915->gt.timelines.mutex);
> 
> Hm, since the loop above bothers restarting after dropping the lock, 
> that implies when we drop the lock here we may not be idle any longer. 
> Or we actually still depend on struct_mutex and this is another small 
> charade? I guess so, since without this patch we also have two path with 
> different levels of idleness guarantee.

Yes. The difference between I915_WAIT_LOCKED and not is that we can only
guarantee we idle if LOCKED (to be replaced by a rw semaphore around
request emission I think).

Iirc we are down to only one "unlocked" user of
i915_gem_wait_for_idle(), that's the vt-d w/a for gen5, which is
probably broken anyway (one poor fool tried it apparently) precisely
because we can't make the guarantee that it remains idle without
struct_mutex.

[snip]

> Looks okay.
> 
> Apart that I am 9/10 worried of how the long game of fine grained 
> locking will untangle, or in other words, how much you managed to nail 
> all the new locks and how much you'll have to re-fiddle with them. :I 
> But maybe you see the end game so I won't project my inability to do so.

There'll always be refiddling! The prospect of KTSAN is a welcome relief
to playing whack-a-mole. My short term goal is be able to generate a
kernel_context request (where we know everything is pinned a priori)
without struct_mutex which should be a much simpler task than the whole
execbuf user interface (but still we have to rearrange various tasks
such as context locking/pinning and acquiring runtime references).
-Chris
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 05/23] drm/i915: Issue engine resets onto idle engines
  2019-01-17 14:34 ` [PATCH 05/23] drm/i915: Issue engine resets onto idle engines Chris Wilson
@ 2019-01-18 12:06   ` Mika Kuoppala
  0 siblings, 0 replies; 50+ messages in thread
From: Mika Kuoppala @ 2019-01-18 12:06 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx

Chris Wilson <chris@chris-wilson.co.uk> writes:

> Always perform the requested reset, even if we believe the engine is
> idle. Presumably there was a reason the caller wanted the reset, and in
> the near future we lose the easy tracking for whether the engine is
> idle.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/i915_reset.c             |  4 ----
>  .../gpu/drm/i915/selftests/intel_hangcheck.c  | 22 +++++--------------
>  2 files changed, 6 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
> index 064fc6da1512..d44b095e2860 100644
> --- a/drivers/gpu/drm/i915/i915_reset.c
> +++ b/drivers/gpu/drm/i915/i915_reset.c
> @@ -1063,10 +1063,6 @@ int i915_reset_engine(struct intel_engine_cs *engine, const char *msg)
>  	GEM_TRACE("%s flags=%lx\n", engine->name, error->flags);
>  	GEM_BUG_ON(!test_bit(I915_RESET_ENGINE + engine->id, &error->flags));
>  
> -	if (i915_seqno_passed(intel_engine_get_seqno(engine),
> -			      intel_engine_last_submit(engine)))
> -		return 0;


It seems you reinstate this later in this series. And
this patch doesn't apply as the i915_reset_engine doesn't
have the idle check.

-Mika

> -
>  	reset_prepare_engine(engine);
>  
>  	if (msg)
> diff --git a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
> index 28144fd72550..9d0cc9d63a1e 100644
> --- a/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
> +++ b/drivers/gpu/drm/i915/selftests/intel_hangcheck.c
> @@ -449,8 +449,6 @@ static int __igt_reset_engine(struct drm_i915_private *i915, bool active)
>  
>  		set_bit(I915_RESET_ENGINE + id, &i915->gpu_error.flags);
>  		do {
> -			u32 seqno = intel_engine_get_seqno(engine);
> -
>  			if (active) {
>  				struct i915_request *rq;
>  
> @@ -479,8 +477,6 @@ static int __igt_reset_engine(struct drm_i915_private *i915, bool active)
>  					break;
>  				}
>  
> -				GEM_BUG_ON(!rq->global_seqno);
> -				seqno = rq->global_seqno - 1;
>  				i915_request_put(rq);
>  			}
>  
> @@ -496,11 +492,10 @@ static int __igt_reset_engine(struct drm_i915_private *i915, bool active)
>  				break;
>  			}
>  
> -			reset_engine_count += active;
>  			if (i915_reset_engine_count(&i915->gpu_error, engine) !=
> -			    reset_engine_count) {
> -				pr_err("%s engine reset %srecorded!\n",
> -				       engine->name, active ? "not " : "");
> +			    ++reset_engine_count) {
> +				pr_err("%s engine reset not recorded!\n",
> +				       engine->name);
>  				err = -EINVAL;
>  				break;
>  			}
> @@ -728,7 +723,6 @@ static int __igt_reset_engines(struct drm_i915_private *i915,
>  
>  		set_bit(I915_RESET_ENGINE + id, &i915->gpu_error.flags);
>  		do {
> -			u32 seqno = intel_engine_get_seqno(engine);
>  			struct i915_request *rq = NULL;
>  
>  			if (flags & TEST_ACTIVE) {
> @@ -756,9 +750,6 @@ static int __igt_reset_engines(struct drm_i915_private *i915,
>  					err = -EIO;
>  					break;
>  				}
> -
> -				GEM_BUG_ON(!rq->global_seqno);
> -				seqno = rq->global_seqno - 1;
>  			}
>  
>  			err = i915_reset_engine(engine, NULL);
> @@ -795,10 +786,9 @@ static int __igt_reset_engines(struct drm_i915_private *i915,
>  
>  		reported = i915_reset_engine_count(&i915->gpu_error, engine);
>  		reported -= threads[engine->id].resets;
> -		if (reported != (flags & TEST_ACTIVE ? count : 0)) {
> -			pr_err("i915_reset_engine(%s:%s): reset %lu times, but reported %lu, expected %lu reported\n",
> -			       engine->name, test_name, count, reported,
> -			       (flags & TEST_ACTIVE ? count : 0));
> +		if (reported != count) {
> +			pr_err("i915_reset_engine(%s:%s): reset %lu times, but reported %lu\n",
> +			       engine->name, test_name, count, reported);
>  			if (!err)
>  				err = -EINVAL;
>  		}
> -- 
> 2.20.1
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 17/23] drm/i915: Share per-timeline HWSP using a slab suballocator
  2019-01-17 14:34 ` [PATCH 17/23] drm/i915: Share per-timeline HWSP using a slab suballocator Chris Wilson
@ 2019-01-18 12:08   ` Tvrtko Ursulin
  0 siblings, 0 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-18 12:08 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> If we restrict ourselves to only using a cacheline for each timeline's
> HWSP (we could go smaller, but want to avoid needless polluting
> cachelines on different engines between different contexts), then we can
> suballocate a single 4k page into 64 different timeline HWSP. By
> treating each fresh allocation as a slab of 64 entries, we can keep it
> around for the next 64 allocation attempts until we need to refresh the
> slab cache.
> 
> John Harrison noted the issue of fragmentation leading to the same worst
> case performance of one page per timeline as before, which can be
> mitigated by adopting a freelist.

Add "in a later patch."?

> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: John Harrison <John.C.Harrison@Intel.com>
> ---
>   drivers/gpu/drm/i915/i915_drv.h      |  5 ++
>   drivers/gpu/drm/i915/i915_timeline.c | 80 ++++++++++++++++++++++++----
>   2 files changed, 74 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 3913900600b7..d59228dabb6e 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1978,6 +1978,11 @@ struct drm_i915_private {
>   		struct i915_gt_timelines {
>   			struct mutex mutex; /* protects list, tainted by GPU */
>   			struct list_head list;
> +
> +			/* Pack multiple timelines' seqnos into the same page */
> +			spinlock_t hwsp_lock;
> +			struct i915_vma *hwsp;
> +			u64 bitmap;

freemap?

>   		} timelines;
>   
>   		struct list_head active_rings;
> diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
> index 380f4d25fb89..e939a9e1a4ab 100644
> --- a/drivers/gpu/drm/i915/i915_timeline.c
> +++ b/drivers/gpu/drm/i915/i915_timeline.c
> @@ -11,26 +11,73 @@
>   
>   static int hwsp_alloc(struct i915_timeline *timeline)
>   {
> +#define NBITS BITS_PER_TYPE(typeof(gt->bitmap))
>   	struct drm_i915_private *i915 = timeline->i915;
> -	struct drm_i915_gem_object *bo;
> +	struct i915_gt_timelines *gt = &i915->gt.timelines;
>   	struct i915_vma *vma;
> +	int offset;
> +
> +	spin_lock(&gt->hwsp_lock);
> +
> +restart:
> +	offset = find_first_bit((unsigned long *)&gt->bitmap, NBITS);
> +	if (offset == NBITS && gt->hwsp) {
> +		i915_vma_put(gt->hwsp);
> +		gt->hwsp = NULL;
> +	}
> +
> +	vma = gt->hwsp;
> +	if (!vma) {
> +		struct drm_i915_gem_object *bo;
> +
> +		spin_unlock(&gt->hwsp_lock);
>   
> -	bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
> -	if (IS_ERR(bo))
> -		return PTR_ERR(bo);
> +		BUILD_BUG_ON(NBITS * CACHELINE_BYTES > PAGE_SIZE);
> +		bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
> +		if (IS_ERR(bo))
> +			return PTR_ERR(bo);
>   
> -	i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
> +		i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
>   
> -	vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
> -	if (IS_ERR(vma)) {
> -		i915_gem_object_put(bo);
> -		return PTR_ERR(vma);
> +		vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
> +		if (IS_ERR(vma)) {
> +			i915_gem_object_put(bo);
> +			return PTR_ERR(vma);
> +		}
> +
> +		spin_lock(&gt->hwsp_lock);
> +		if (gt->hwsp) {
> +			i915_gem_object_put(bo);
> +			goto restart;
> +		}
> +
> +		gt->hwsp = vma;
> +		gt->bitmap = ~0ull;
> +		offset = 0;
>   	}
>   
> -	timeline->hwsp_ggtt = vma;
> -	timeline->hwsp_offset = 0;
> +	gt->bitmap &= ~BIT_ULL(offset);
> +
> +	spin_unlock(&gt->hwsp_lock);
> +
> +	timeline->hwsp_ggtt = i915_vma_get(vma);
> +	timeline->hwsp_offset = offset * CACHELINE_BYTES;
>   
>   	return 0;
> +#undef NBITS
> +}
> +
> +static void hwsp_free(struct i915_timeline *timeline)
> +{
> +	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
> +
> +	if (timeline->hwsp_ggtt != gt->hwsp)
> +		return;
> +
> +	spin_lock(&gt->hwsp_lock);
> +	if (timeline->hwsp_ggtt == gt->hwsp)
> +		gt->bitmap |= BIT_ULL(timeline->hwsp_offset / CACHELINE_BYTES);
> +	spin_unlock(&gt->hwsp_lock);
>   }

There is some asymmetry in hwsp_alloc dealing with both backing store 
and bitmap management, while hwsp_free only deals with bitmap 
management. I'll have a look in the next patch if it all goes away.

>   
>   int i915_timeline_init(struct drm_i915_private *i915,
> @@ -65,6 +112,7 @@ int i915_timeline_init(struct drm_i915_private *i915,
>   
>   	vaddr = i915_gem_object_pin_map(timeline->hwsp_ggtt->obj, I915_MAP_WB);
>   	if (IS_ERR(vaddr)) {
> +		hwsp_free(timeline);
>   		i915_vma_put(timeline->hwsp_ggtt);
>   		return PTR_ERR(vaddr);
>   	}
> @@ -99,6 +147,8 @@ void i915_timelines_init(struct drm_i915_private *i915)
>   	mutex_init(&gt->mutex);
>   	INIT_LIST_HEAD(&gt->list);
>   
> +	spin_lock_init(&gt->hwsp_lock);
> +
>   	/* via i915_gem_wait_for_idle() */
>   	i915_gem_shrinker_taints_mutex(i915, &gt->mutex);
>   }
> @@ -144,6 +194,9 @@ void i915_timeline_fini(struct i915_timeline *timeline)
>   	list_del(&timeline->link);
>   	mutex_unlock(&gt->mutex);
>   
> +	i915_syncmap_free(&timeline->sync);
> +	hwsp_free(timeline);
> +
>   	i915_gem_object_unpin_map(timeline->hwsp_ggtt->obj);
>   	i915_vma_put(timeline->hwsp_ggtt);
>   }
> @@ -211,9 +264,14 @@ void __i915_timeline_free(struct kref *kref)
>   void i915_timelines_fini(struct drm_i915_private *i915)
>   {
>   	struct i915_gt_timelines *gt = &i915->gt.timelines;
> +	struct i915_vma *vma;
>   
>   	GEM_BUG_ON(!list_empty(&gt->list));
>   
> +	vma = fetch_and_zero(&i915->gt.timelines.hwsp);
> +	if (vma)
> +		i915_vma_put(vma);
> +
>   	mutex_destroy(&gt->mutex);
>   }
>   
> 

Looks okay to me. But best wait for John to give it a check over as well.

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko
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^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 18/23] drm/i915: Keep all partially allocated HWSP on a freelist
  2019-01-17 14:34 ` [PATCH 18/23] drm/i915: Keep all partially allocated HWSP on a freelist Chris Wilson
@ 2019-01-18 12:12   ` Mika Kuoppala
  2019-01-18 12:25   ` Tvrtko Ursulin
  1 sibling, 0 replies; 50+ messages in thread
From: Mika Kuoppala @ 2019-01-18 12:12 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx

Chris Wilson <chris@chris-wilson.co.uk> writes:

> Keep track of partially allocated pages for use in allocating future
> timeline HWSP. This is still without migration, so it is possible for

timeline from HWSP?

> the system to end up with each timeline in its own page, but we ensure
> that no new allocation would needless allocate a fresh page!

s/needless/needlessly.
-Mika

>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: John Harrison <John.C.Harrison@Intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.h      |  3 +-
>  drivers/gpu/drm/i915/i915_timeline.c | 81 +++++++++++++++++-----------
>  2 files changed, 50 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index d59228dabb6e..0bebef428f1e 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1981,8 +1981,7 @@ struct drm_i915_private {
>  
>  			/* Pack multiple timelines' seqnos into the same page */
>  			spinlock_t hwsp_lock;
> -			struct i915_vma *hwsp;
> -			u64 bitmap;
> +			struct list_head hwsp;
>  		} timelines;
>  
>  		struct list_head active_rings;
> diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
> index e939a9e1a4ab..64bb1ce24318 100644
> --- a/drivers/gpu/drm/i915/i915_timeline.c
> +++ b/drivers/gpu/drm/i915/i915_timeline.c
> @@ -9,74 +9,94 @@
>  #include "i915_timeline.h"
>  #include "i915_syncmap.h"
>  
> +struct i915_timeline_hwsp {
> +	struct list_head link;
> +	struct i915_vma *vma;
> +	u64 bitmap;
> +};
> +
>  static int hwsp_alloc(struct i915_timeline *timeline)
>  {
> -#define NBITS BITS_PER_TYPE(typeof(gt->bitmap))
>  	struct drm_i915_private *i915 = timeline->i915;
>  	struct i915_gt_timelines *gt = &i915->gt.timelines;
> -	struct i915_vma *vma;
> +	struct i915_timeline_hwsp *hwsp;
>  	int offset;
>  
>  	spin_lock(&gt->hwsp_lock);
>  
> -restart:
> -	offset = find_first_bit((unsigned long *)&gt->bitmap, NBITS);
> -	if (offset == NBITS && gt->hwsp) {
> -		i915_vma_put(gt->hwsp);
> -		gt->hwsp = NULL;
> -	}
> -
> -	vma = gt->hwsp;
> -	if (!vma) {
> +	hwsp = list_first_entry_or_null(&gt->hwsp, typeof(*hwsp), link);
> +	if (!hwsp) {
>  		struct drm_i915_gem_object *bo;
> +		struct i915_vma *vma;
>  
>  		spin_unlock(&gt->hwsp_lock);
>  
> -		BUILD_BUG_ON(NBITS * CACHELINE_BYTES > PAGE_SIZE);
> +		hwsp = kmalloc(sizeof(*hwsp), GFP_KERNEL);
> +		if (!hwsp)
> +			return -ENOMEM;
> +
> +		BUILD_BUG_ON(BITS_PER_TYPE(hwsp->bitmap) * CACHELINE_BYTES > PAGE_SIZE);
>  		bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
> -		if (IS_ERR(bo))
> +		if (IS_ERR(bo)) {
> +			kfree(hwsp);
>  			return PTR_ERR(bo);
> +		}
>  
>  		i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
>  
>  		vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
>  		if (IS_ERR(vma)) {
>  			i915_gem_object_put(bo);
> +			kfree(hwsp);
>  			return PTR_ERR(vma);
>  		}
>  
> -		spin_lock(&gt->hwsp_lock);
> -		if (gt->hwsp) {
> -			i915_gem_object_put(bo);
> -			goto restart;
> -		}
> +		vma->private = hwsp;
> +		hwsp->vma = vma;
> +		hwsp->bitmap = ~0ull;
>  
> -		gt->hwsp = vma;
> -		gt->bitmap = ~0ull;
> -		offset = 0;
> +		spin_lock(&gt->hwsp_lock);
> +		list_add(&hwsp->link, &gt->hwsp);
>  	}
>  
> -	gt->bitmap &= ~BIT_ULL(offset);
> +	GEM_BUG_ON(!hwsp->bitmap);
> +	offset = __ffs64(hwsp->bitmap);
> +	hwsp->bitmap &= ~BIT_ULL(offset);
> +	if (!hwsp->bitmap)
> +		list_del(&hwsp->link);
>  
>  	spin_unlock(&gt->hwsp_lock);
>  
> -	timeline->hwsp_ggtt = i915_vma_get(vma);
> +	timeline->hwsp_ggtt = i915_vma_get(hwsp->vma);
>  	timeline->hwsp_offset = offset * CACHELINE_BYTES;
>  
> +	GEM_BUG_ON(timeline->hwsp_ggtt->private != hwsp);
> +
>  	return 0;
> -#undef NBITS
>  }
>  
>  static void hwsp_free(struct i915_timeline *timeline)
>  {
>  	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
> +	struct i915_timeline_hwsp *hwsp;
>  
> -	if (timeline->hwsp_ggtt != gt->hwsp)
> +	hwsp = timeline->hwsp_ggtt->private;
> +	if (!hwsp)
>  		return;
>  
>  	spin_lock(&gt->hwsp_lock);
> -	if (timeline->hwsp_ggtt == gt->hwsp)
> -		gt->bitmap |= BIT_ULL(timeline->hwsp_offset / CACHELINE_BYTES);
> +
> +	if (!hwsp->bitmap)
> +		list_add_tail(&hwsp->link, &gt->hwsp);
> +
> +	hwsp->bitmap |= BIT_ULL(timeline->hwsp_offset / CACHELINE_BYTES);
> +
> +	if (hwsp->bitmap == ~0ull) {
> +		i915_vma_put(hwsp->vma);
> +		list_del(&hwsp->link);
> +		kfree(hwsp);
> +	}
> +
>  	spin_unlock(&gt->hwsp_lock);
>  }
>  
> @@ -148,6 +168,7 @@ void i915_timelines_init(struct drm_i915_private *i915)
>  	INIT_LIST_HEAD(&gt->list);
>  
>  	spin_lock_init(&gt->hwsp_lock);
> +	INIT_LIST_HEAD(&gt->hwsp);
>  
>  	/* via i915_gem_wait_for_idle() */
>  	i915_gem_shrinker_taints_mutex(i915, &gt->mutex);
> @@ -264,13 +285,9 @@ void __i915_timeline_free(struct kref *kref)
>  void i915_timelines_fini(struct drm_i915_private *i915)
>  {
>  	struct i915_gt_timelines *gt = &i915->gt.timelines;
> -	struct i915_vma *vma;
>  
>  	GEM_BUG_ON(!list_empty(&gt->list));
> -
> -	vma = fetch_and_zero(&i915->gt.timelines.hwsp);
> -	if (vma)
> -		i915_vma_put(vma);
> +	GEM_BUG_ON(!list_empty(&gt->hwsp));
>  
>  	mutex_destroy(&gt->mutex);
>  }
> -- 
> 2.20.1
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 18/23] drm/i915: Keep all partially allocated HWSP on a freelist
  2019-01-17 14:34 ` [PATCH 18/23] drm/i915: Keep all partially allocated HWSP on a freelist Chris Wilson
  2019-01-18 12:12   ` Mika Kuoppala
@ 2019-01-18 12:25   ` Tvrtko Ursulin
  1 sibling, 0 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-18 12:25 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:34, Chris Wilson wrote:
> Keep track of partially allocated pages for use in allocating future
> timeline HWSP. This is still without migration, so it is possible for
> the system to end up with each timeline in its own page, but we ensure
> that no new allocation would needless allocate a fresh page!
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: John Harrison <John.C.Harrison@Intel.com>
> ---
>   drivers/gpu/drm/i915/i915_drv.h      |  3 +-
>   drivers/gpu/drm/i915/i915_timeline.c | 81 +++++++++++++++++-----------
>   2 files changed, 50 insertions(+), 34 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index d59228dabb6e..0bebef428f1e 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1981,8 +1981,7 @@ struct drm_i915_private {
>   
>   			/* Pack multiple timelines' seqnos into the same page */
>   			spinlock_t hwsp_lock;
> -			struct i915_vma *hwsp;
> -			u64 bitmap;
> +			struct list_head hwsp;

hwsp_list to use our established convention? Actually, hwsp_free_list 
would be even more self-documenting.

>   		} timelines;
>   
>   		struct list_head active_rings;
> diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
> index e939a9e1a4ab..64bb1ce24318 100644
> --- a/drivers/gpu/drm/i915/i915_timeline.c
> +++ b/drivers/gpu/drm/i915/i915_timeline.c
> @@ -9,74 +9,94 @@
>   #include "i915_timeline.h"
>   #include "i915_syncmap.h"
>   
> +struct i915_timeline_hwsp {
> +	struct list_head link;
> +	struct i915_vma *vma;
> +	u64 bitmap;
> +};
> +
>   static int hwsp_alloc(struct i915_timeline *timeline)
>   {
> -#define NBITS BITS_PER_TYPE(typeof(gt->bitmap))
>   	struct drm_i915_private *i915 = timeline->i915;
>   	struct i915_gt_timelines *gt = &i915->gt.timelines;
> -	struct i915_vma *vma;
> +	struct i915_timeline_hwsp *hwsp;
>   	int offset;
>   
>   	spin_lock(&gt->hwsp_lock);
>   
> -restart:
> -	offset = find_first_bit((unsigned long *)&gt->bitmap, NBITS);
> -	if (offset == NBITS && gt->hwsp) {
> -		i915_vma_put(gt->hwsp);
> -		gt->hwsp = NULL;
> -	}
> -
> -	vma = gt->hwsp;
> -	if (!vma) {
> +	hwsp = list_first_entry_or_null(&gt->hwsp, typeof(*hwsp), link);
> +	if (!hwsp) {
>   		struct drm_i915_gem_object *bo;
> +		struct i915_vma *vma;
>   
>   		spin_unlock(&gt->hwsp_lock);
>   
> -		BUILD_BUG_ON(NBITS * CACHELINE_BYTES > PAGE_SIZE);
> +		hwsp = kmalloc(sizeof(*hwsp), GFP_KERNEL);
> +		if (!hwsp)
> +			return -ENOMEM;
> +
> +		BUILD_BUG_ON(BITS_PER_TYPE(hwsp->bitmap) * CACHELINE_BYTES > PAGE_SIZE);
>   		bo = i915_gem_object_create_internal(i915, PAGE_SIZE);
> -		if (IS_ERR(bo))
> +		if (IS_ERR(bo)) {
> +			kfree(hwsp);
>   			return PTR_ERR(bo);
> +		}
>   
>   		i915_gem_object_set_cache_level(bo, I915_CACHE_LLC);
>   
>   		vma = i915_vma_instance(bo, &i915->ggtt.vm, NULL);
>   		if (IS_ERR(vma)) {
>   			i915_gem_object_put(bo);
> +			kfree(hwsp);
>   			return PTR_ERR(vma);
>   		}
>   
> -		spin_lock(&gt->hwsp_lock);
> -		if (gt->hwsp) {
> -			i915_gem_object_put(bo);
> -			goto restart;
> -		}
> +		vma->private = hwsp;
> +		hwsp->vma = vma;
> +		hwsp->bitmap = ~0ull;
>   
> -		gt->hwsp = vma;
> -		gt->bitmap = ~0ull;
> -		offset = 0;
> +		spin_lock(&gt->hwsp_lock);
> +		list_add(&hwsp->link, &gt->hwsp);
>   	}
>   
> -	gt->bitmap &= ~BIT_ULL(offset);
> +	GEM_BUG_ON(!hwsp->bitmap);
> +	offset = __ffs64(hwsp->bitmap);

I never can remember from which side is first. With find_first_bit I 
didn't have this problem. :)

> +	hwsp->bitmap &= ~BIT_ULL(offset);
> +	if (!hwsp->bitmap)
> +		list_del(&hwsp->link);
>   
>   	spin_unlock(&gt->hwsp_lock);
>   
> -	timeline->hwsp_ggtt = i915_vma_get(vma);
> +	timeline->hwsp_ggtt = i915_vma_get(hwsp->vma);
>   	timeline->hwsp_offset = offset * CACHELINE_BYTES;
>   
> +	GEM_BUG_ON(timeline->hwsp_ggtt->private != hwsp);
> +
>   	return 0;
> -#undef NBITS
>   }
>   
>   static void hwsp_free(struct i915_timeline *timeline)
>   {
>   	struct i915_gt_timelines *gt = &timeline->i915->gt.timelines;
> +	struct i915_timeline_hwsp *hwsp;
>   
> -	if (timeline->hwsp_ggtt != gt->hwsp)
> +	hwsp = timeline->hwsp_ggtt->private;
> +	if (!hwsp)
>   		return;

Hm is there a path to this return now?

>   
>   	spin_lock(&gt->hwsp_lock);
> -	if (timeline->hwsp_ggtt == gt->hwsp)
> -		gt->bitmap |= BIT_ULL(timeline->hwsp_offset / CACHELINE_BYTES);
> +
> +	if (!hwsp->bitmap)
> +		list_add_tail(&hwsp->link, &gt->hwsp);

I got so deep into the code that I forgot to remind to add some more 
comments. :) This seems like a good place - oh well.. who would come up 
with good comments anyway.

> +
> +	hwsp->bitmap |= BIT_ULL(timeline->hwsp_offset / CACHELINE_BYTES);
> +
> +	if (hwsp->bitmap == ~0ull) {
> +		i915_vma_put(hwsp->vma);
> +		list_del(&hwsp->link);
> +		kfree(hwsp);
> +	}
> +
>   	spin_unlock(&gt->hwsp_lock);
>   }
>   
> @@ -148,6 +168,7 @@ void i915_timelines_init(struct drm_i915_private *i915)
>   	INIT_LIST_HEAD(&gt->list);
>   
>   	spin_lock_init(&gt->hwsp_lock);
> +	INIT_LIST_HEAD(&gt->hwsp);
>   
>   	/* via i915_gem_wait_for_idle() */
>   	i915_gem_shrinker_taints_mutex(i915, &gt->mutex);
> @@ -264,13 +285,9 @@ void __i915_timeline_free(struct kref *kref)
>   void i915_timelines_fini(struct drm_i915_private *i915)
>   {
>   	struct i915_gt_timelines *gt = &i915->gt.timelines;
> -	struct i915_vma *vma;
>   
>   	GEM_BUG_ON(!list_empty(&gt->list));
> -
> -	vma = fetch_and_zero(&i915->gt.timelines.hwsp);
> -	if (vma)
> -		i915_vma_put(vma);
> +	GEM_BUG_ON(!list_empty(&gt->hwsp));
>   
>   	mutex_destroy(&gt->mutex);
>   }
> 

The only thing missing is a selftest which will exercise some "chunky" 
timeline allocations and frees. Just to exercise this logic a bit.. 
something like maybe (in very crude pseudo-code):

	blocks = { 1, 64 / 2, 64 - 1, 64, 64 + 1, 64 * 3 / 2 };

	for_each_block {
		for 0..block
			tl_emit_rq(block);
		sync
		if (flags & LINEAR)
			for 0..block
				tl_free
		else if (flags & RANDOM_FREE)
			...
	}

It's a very terse and sloppy sketch but I think you'll know what I am 
trying to say.

Regards,

Tvrtko
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

* Re: [PATCH 19/23] drm/i915: Track the context's seqno in its own timeline HWSP
  2019-01-17 14:35 ` [PATCH 19/23] drm/i915: Track the context's seqno in its own timeline HWSP Chris Wilson
@ 2019-01-18 14:10   ` Tvrtko Ursulin
  0 siblings, 0 replies; 50+ messages in thread
From: Tvrtko Ursulin @ 2019-01-18 14:10 UTC (permalink / raw)
  To: Chris Wilson, intel-gfx


On 17/01/2019 14:35, Chris Wilson wrote:
> Now that we have allocated ourselves a cacheline to store a breadcrumb,
> we can emit a write from the GPU into the timeline's HWSP of the
> per-context seqno as we complete each request. This drops the mirroring
> of the per-engine HWSP and allows each context to operate independently.
> We do not need to unwind the per-context timeline, and so requests are
> always consistent with the timeline breadcrumb, greatly simplifying the
> completion checks as we no longer need to be concerned about the
> global_seqno changing mid check.
> 
> At this point, we are emitting both per-context and global seqno and
> still using the single per-engine execution timeline for resolving
> interrupts.
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_gem.c              |  2 +-
>   drivers/gpu/drm/i915/i915_request.c          |  2 +-
>   drivers/gpu/drm/i915/i915_request.h          | 27 ++----
>   drivers/gpu/drm/i915/i915_reset.c            |  1 +
>   drivers/gpu/drm/i915/i915_vma.h              |  7 ++
>   drivers/gpu/drm/i915/intel_lrc.c             | 32 ++++---
>   drivers/gpu/drm/i915/intel_ringbuffer.c      | 91 ++++++++++++++------
>   drivers/gpu/drm/i915/selftests/mock_engine.c |  8 +-
>   8 files changed, 109 insertions(+), 61 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 3c6091021290..a5bd51987c0d 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -2890,7 +2890,7 @@ i915_gem_find_active_request(struct intel_engine_cs *engine)
>   	 */
>   	spin_lock_irqsave(&engine->timeline.lock, flags);
>   	list_for_each_entry(request, &engine->timeline.requests, link) {
> -		if (__i915_request_completed(request, request->global_seqno))
> +		if (i915_request_completed(request))
>   			continue;
>   
>   		active = request;
> diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
> index 7d068c406a49..0d7b71aff28f 100644
> --- a/drivers/gpu/drm/i915/i915_request.c
> +++ b/drivers/gpu/drm/i915/i915_request.c
> @@ -614,7 +614,7 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx)
>   	rq->ring = ce->ring;
>   	rq->timeline = ce->ring->timeline;
>   	GEM_BUG_ON(rq->timeline == &engine->timeline);
> -	rq->hwsp_seqno = &engine->status_page.addr[I915_GEM_HWS_INDEX];
> +	rq->hwsp_seqno = rq->timeline->hwsp_seqno;
>   
>   	spin_lock_init(&rq->lock);
>   	dma_fence_init(&rq->fence,
> diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h
> index 4dd22dadf5ce..a16a3b7f7d92 100644
> --- a/drivers/gpu/drm/i915/i915_request.h
> +++ b/drivers/gpu/drm/i915/i915_request.h
> @@ -324,32 +324,21 @@ static inline u32 hwsp_seqno(const struct i915_request *rq)
>    */
>   static inline bool i915_request_started(const struct i915_request *rq)
>   {
> -	u32 seqno;
> -
> -	seqno = i915_request_global_seqno(rq);
> -	if (!seqno) /* not yet submitted to HW */
> -		return false;
> -
> -	return i915_seqno_passed(hwsp_seqno(rq), seqno - 1);
> +	return i915_seqno_passed(hwsp_seqno(rq), rq->fence.seqno - 1);
>   }
>   
> -static inline bool
> -__i915_request_completed(const struct i915_request *rq, u32 seqno)
> +static inline bool i915_request_completed(const struct i915_request *rq)
>   {
> -	GEM_BUG_ON(!seqno);
> -	return i915_seqno_passed(hwsp_seqno(rq), seqno) &&
> -		seqno == i915_request_global_seqno(rq);
> +	return i915_seqno_passed(hwsp_seqno(rq), rq->fence.seqno);
>   }
>   
> -static inline bool i915_request_completed(const struct i915_request *rq)
> +static inline void i915_request_fake_complete(const struct i915_request *rq)

I don't like this name. force_complete? force_hwsp_complete? Or turn it 
around, i915_hwsp_write(rq->hwsp_seqno, rq->fence.seqno)? Now it is 
beginning to remind of intel_write_status_page. :)

>   {
> -	u32 seqno;
> -
> -	seqno = i915_request_global_seqno(rq);
> -	if (!seqno)
> -		return false;
> +	/* Don't allow ourselves to accidentally go backwards. */
> +	if (i915_request_completed(rq))
> +		return;
>   
> -	return __i915_request_completed(rq, seqno);
> +	WRITE_ONCE(*(u32 *)rq->hwsp_seqno, rq->fence.seqno);
>   }
>   
>   void i915_retire_requests(struct drm_i915_private *i915);
> diff --git a/drivers/gpu/drm/i915/i915_reset.c b/drivers/gpu/drm/i915/i915_reset.c
> index 12e5a2bc825c..eff76558b958 100644
> --- a/drivers/gpu/drm/i915/i915_reset.c
> +++ b/drivers/gpu/drm/i915/i915_reset.c
> @@ -756,6 +756,7 @@ static void nop_submit_request(struct i915_request *request)
>   
>   	spin_lock_irqsave(&request->engine->timeline.lock, flags);
>   	__i915_request_submit(request);
> +	i915_request_fake_complete(request);
>   	intel_engine_write_global_seqno(request->engine, request->global_seqno);
>   	spin_unlock_irqrestore(&request->engine->timeline.lock, flags);
>   }
> diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
> index 5793abe509a2..18be786a970d 100644
> --- a/drivers/gpu/drm/i915/i915_vma.h
> +++ b/drivers/gpu/drm/i915/i915_vma.h
> @@ -221,6 +221,13 @@ static inline u32 i915_ggtt_offset(const struct i915_vma *vma)
>   	return lower_32_bits(vma->node.start);
>   }
>   
> +/* XXX inline spaghetti */
> +static inline u32 i915_timeline_seqno_address(const struct i915_timeline *tl)
> +{
> +	GEM_BUG_ON(!tl->pin_count);
> +	return i915_ggtt_offset(tl->hwsp_ggtt) + tl->hwsp_offset;
> +}
> +
>   static inline u32 i915_ggtt_pin_bias(struct i915_vma *vma)
>   {
>   	return i915_vm_to_ggtt(vma->vm)->pin_bias;
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index a624e644fbd7..593928dd6bbe 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -827,10 +827,10 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
>   	list_for_each_entry(rq, &engine->timeline.requests, link) {
>   		GEM_BUG_ON(!rq->global_seqno);
>   
> -		if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &rq->fence.flags))
> -			continue;
> +		if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &rq->fence.flags))
> +			dma_fence_set_error(&rq->fence, -EIO);
>   
> -		dma_fence_set_error(&rq->fence, -EIO);
> +		i915_request_fake_complete(rq);
>   	}
>   
>   	/* Flush the queued requests to the timeline list (for retiring). */
> @@ -843,6 +843,7 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)
>   
>   			dma_fence_set_error(&rq->fence, -EIO);
>   			__i915_request_submit(rq);
> +			i915_request_fake_complete(rq);
>   		}
>   
>   		rb_erase_cached(&p->node, &execlists->queue);
> @@ -2022,31 +2023,40 @@ static void gen8_emit_breadcrumb(struct i915_request *request, u32 *cs)
>   	/* w/a: bit 5 needs to be zero for MI_FLUSH_DW address. */
>   	BUILD_BUG_ON(I915_GEM_HWS_INDEX_ADDR & (1 << 5));
>   
> -	cs = gen8_emit_ggtt_write(cs, request->global_seqno,
> +	cs = gen8_emit_ggtt_write(cs,
> +				  request->fence.seqno,
> +				  i915_timeline_seqno_address(request->timeline));
> +
> +	cs = gen8_emit_ggtt_write(cs,
> +				  request->global_seqno,
>   				  intel_hws_seqno_address(request->engine));
> +
>   	*cs++ = MI_USER_INTERRUPT;
>   	*cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
> +
>   	request->tail = intel_ring_offset(request, cs);
>   	assert_ring_tail_valid(request->ring, request->tail);
>   
>   	gen8_emit_wa_tail(request, cs);
>   }
> -static const int gen8_emit_breadcrumb_sz = 6 + WA_TAIL_DWORDS;
> +static const int gen8_emit_breadcrumb_sz = 10 + WA_TAIL_DWORDS;
>   
>   static void gen8_emit_breadcrumb_rcs(struct i915_request *request, u32 *cs)
>   {
> -	/* We're using qword write, seqno should be aligned to 8 bytes. */
> -	BUILD_BUG_ON(I915_GEM_HWS_INDEX & 1);
> -
>   	cs = gen8_emit_ggtt_write_rcs(cs,
> -				      request->global_seqno,
> -				      intel_hws_seqno_address(request->engine),
> +				      request->fence.seqno,
> +				      i915_timeline_seqno_address(request->timeline),
>   				      PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
>   				      PIPE_CONTROL_DEPTH_CACHE_FLUSH |
>   				      PIPE_CONTROL_DC_FLUSH_ENABLE |
>   				      PIPE_CONTROL_FLUSH_ENABLE |
>   				      PIPE_CONTROL_CS_STALL);
>   
> +	cs = gen8_emit_ggtt_write_rcs(cs,
> +				      request->global_seqno,
> +				      intel_hws_seqno_address(request->engine),
> +				      PIPE_CONTROL_CS_STALL);
> +
>   	*cs++ = MI_USER_INTERRUPT;
>   	*cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
>   
> @@ -2055,7 +2065,7 @@ static void gen8_emit_breadcrumb_rcs(struct i915_request *request, u32 *cs)
>   
>   	gen8_emit_wa_tail(request, cs);
>   }
> -static const int gen8_emit_breadcrumb_rcs_sz = 8 + WA_TAIL_DWORDS;
> +static const int gen8_emit_breadcrumb_rcs_sz = 14 + WA_TAIL_DWORDS;
>   
>   static int gen8_init_rcs_context(struct i915_request *rq)
>   {
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index 5887304bc3ae..bcc700e7037b 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -325,6 +325,12 @@ static void gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   		 PIPE_CONTROL_DC_FLUSH_ENABLE |
>   		 PIPE_CONTROL_QW_WRITE |
>   		 PIPE_CONTROL_CS_STALL);
> +	*cs++ = i915_timeline_seqno_address(rq->timeline) |
> +		PIPE_CONTROL_GLOBAL_GTT;
> +	*cs++ = rq->fence.seqno;
> +
> +	*cs++ = GFX_OP_PIPE_CONTROL(4);
> +	*cs++ = PIPE_CONTROL_QW_WRITE | PIPE_CONTROL_CS_STALL;
>   	*cs++ = intel_hws_seqno_address(rq->engine) | PIPE_CONTROL_GLOBAL_GTT;
>   	*cs++ = rq->global_seqno;
>   
> @@ -334,7 +340,7 @@ static void gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   	rq->tail = intel_ring_offset(rq, cs);
>   	assert_ring_tail_valid(rq->ring, rq->tail);
>   }
> -static const int gen6_rcs_emit_breadcrumb_sz = 14;
> +static const int gen6_rcs_emit_breadcrumb_sz = 18;
>   
>   static int
>   gen7_render_ring_cs_stall_wa(struct i915_request *rq)
> @@ -425,6 +431,13 @@ static void gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   		 PIPE_CONTROL_QW_WRITE |
>   		 PIPE_CONTROL_GLOBAL_GTT_IVB |
>   		 PIPE_CONTROL_CS_STALL);
> +	*cs++ = i915_timeline_seqno_address(rq->timeline);
> +	*cs++ = rq->fence.seqno;
> +
> +	*cs++ = GFX_OP_PIPE_CONTROL(4);
> +	*cs++ = (PIPE_CONTROL_QW_WRITE |
> +		 PIPE_CONTROL_GLOBAL_GTT_IVB |
> +		 PIPE_CONTROL_CS_STALL);
>   	*cs++ = intel_hws_seqno_address(rq->engine);
>   	*cs++ = rq->global_seqno;
>   
> @@ -434,27 +447,37 @@ static void gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   	rq->tail = intel_ring_offset(rq, cs);
>   	assert_ring_tail_valid(rq->ring, rq->tail);
>   }
> -static const int gen7_rcs_emit_breadcrumb_sz = 6;
> +static const int gen7_rcs_emit_breadcrumb_sz = 10;
>   
>   static void gen6_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   {
> -	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW;
> -	*cs++ = intel_hws_seqno_address(rq->engine) | MI_FLUSH_DW_USE_GTT;
> +	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
> +	*cs++ = I915_GEM_HWS_SEQNO_ADDR | MI_FLUSH_DW_USE_GTT;
> +	*cs++ = rq->fence.seqno;
> +
> +	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
> +	*cs++ = I915_GEM_HWS_INDEX_ADDR | MI_FLUSH_DW_USE_GTT;
>   	*cs++ = rq->global_seqno;
> +
>   	*cs++ = MI_USER_INTERRUPT;
> +	*cs++ = MI_NOOP;
>   
>   	rq->tail = intel_ring_offset(rq, cs);
>   	assert_ring_tail_valid(rq->ring, rq->tail);
>   }
> -static const int gen6_xcs_emit_breadcrumb_sz = 4;
> +static const int gen6_xcs_emit_breadcrumb_sz = 8;
>   
>   #define GEN7_XCS_WA 32
>   static void gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   {
>   	int i;
>   
> -	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW;
> -	*cs++ = intel_hws_seqno_address(rq->engine) | MI_FLUSH_DW_USE_GTT;
> +	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
> +	*cs++ = I915_GEM_HWS_SEQNO_ADDR | MI_FLUSH_DW_USE_GTT;
> +	*cs++ = rq->fence.seqno;
> +
> +	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
> +	*cs++ = I915_GEM_HWS_INDEX_ADDR | MI_FLUSH_DW_USE_GTT;
>   	*cs++ = rq->global_seqno;
>   
>   	for (i = 0; i < GEN7_XCS_WA; i++) {
> @@ -468,12 +491,11 @@ static void gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   	*cs++ = 0;
>   
>   	*cs++ = MI_USER_INTERRUPT;
> -	*cs++ = MI_NOOP;
>   
>   	rq->tail = intel_ring_offset(rq, cs);
>   	assert_ring_tail_valid(rq->ring, rq->tail);
>   }
> -static const int gen7_xcs_emit_breadcrumb_sz = 8 + GEN7_XCS_WA * 3;
> +static const int gen7_xcs_emit_breadcrumb_sz = 10 + GEN7_XCS_WA * 3;
>   #undef GEN7_XCS_WA
>   
>   static void set_hwstam(struct intel_engine_cs *engine, u32 mask)
> @@ -733,7 +755,7 @@ static void reset_ring(struct intel_engine_cs *engine, bool stalled)
>   	rq = NULL;
>   	spin_lock_irqsave(&tl->lock, flags);
>   	list_for_each_entry(pos, &tl->requests, link) {
> -		if (!__i915_request_completed(pos, pos->global_seqno)) {
> +		if (!i915_request_completed(pos)) {
>   			rq = pos;
>   			break;
>   		}
> @@ -875,11 +897,10 @@ static void cancel_requests(struct intel_engine_cs *engine)
>   	list_for_each_entry(request, &engine->timeline.requests, link) {
>   		GEM_BUG_ON(!request->global_seqno);
>   
> -		if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
> -			     &request->fence.flags))
> -			continue;
> -
> -		dma_fence_set_error(&request->fence, -EIO);
> +		if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
> +			      &request->fence.flags))
> +			dma_fence_set_error(&request->fence, -EIO);
> +		i915_request_fake_complete(request);
>   	}
>   
>   	intel_write_status_page(engine,
> @@ -903,27 +924,38 @@ static void i9xx_submit_request(struct i915_request *request)
>   
>   static void i9xx_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   {
> +	GEM_BUG_ON(rq->timeline->hwsp_ggtt != rq->engine->status_page.vma);
> +
>   	*cs++ = MI_FLUSH;
>   
> +	*cs++ = MI_STORE_DWORD_INDEX;
> +	*cs++ = I915_GEM_HWS_SEQNO_ADDR;
> +	*cs++ = rq->fence.seqno;
> +
>   	*cs++ = MI_STORE_DWORD_INDEX;
>   	*cs++ = I915_GEM_HWS_INDEX_ADDR;
>   	*cs++ = rq->global_seqno;
>   
>   	*cs++ = MI_USER_INTERRUPT;
> -	*cs++ = MI_NOOP;
>   
>   	rq->tail = intel_ring_offset(rq, cs);
>   	assert_ring_tail_valid(rq->ring, rq->tail);
>   }
> -static const int i9xx_emit_breadcrumb_sz = 6;
> +static const int i9xx_emit_breadcrumb_sz = 8;
>   
>   #define GEN5_WA_STORES 8 /* must be at least 1! */
>   static void gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   {
>   	int i;
>   
> +	GEM_BUG_ON(rq->timeline->hwsp_ggtt != rq->engine->status_page.vma);
> +
>   	*cs++ = MI_FLUSH;
>   
> +	*cs++ = MI_STORE_DWORD_INDEX;
> +	*cs++ = I915_GEM_HWS_SEQNO_ADDR;
> +	*cs++ = rq->fence.seqno;
> +
>   	BUILD_BUG_ON(GEN5_WA_STORES < 1);
>   	for (i = 0; i < GEN5_WA_STORES; i++) {
>   		*cs++ = MI_STORE_DWORD_INDEX;
> @@ -932,11 +964,12 @@ static void gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs)
>   	}
>   
>   	*cs++ = MI_USER_INTERRUPT;
> +	*cs++ = MI_NOOP;
>   
>   	rq->tail = intel_ring_offset(rq, cs);
>   	assert_ring_tail_valid(rq->ring, rq->tail);
>   }
> -static const int gen5_emit_breadcrumb_sz = GEN5_WA_STORES * 3 + 2;
> +static const int gen5_emit_breadcrumb_sz = GEN5_WA_STORES * 3 + 6;
>   #undef GEN5_WA_STORES
>   
>   static void
> @@ -1163,6 +1196,10 @@ int intel_ring_pin(struct intel_ring *ring)
>   
>   	GEM_BUG_ON(ring->vaddr);
>   
> +	ret = i915_timeline_pin(ring->timeline);
> +	if (ret)
> +		return ret;
> +
>   	flags = PIN_GLOBAL;
>   
>   	/* Ring wraparound at offset 0 sometimes hangs. No idea why. */
> @@ -1179,28 +1216,32 @@ int intel_ring_pin(struct intel_ring *ring)
>   		else
>   			ret = i915_gem_object_set_to_cpu_domain(vma->obj, true);
>   		if (unlikely(ret))
> -			return ret;
> +			goto unpin_timeline;
>   	}
>   
>   	ret = i915_vma_pin(vma, 0, 0, flags);
>   	if (unlikely(ret))
> -		return ret;
> +		goto unpin_timeline;
>   
>   	if (i915_vma_is_map_and_fenceable(vma))
>   		addr = (void __force *)i915_vma_pin_iomap(vma);
>   	else
>   		addr = i915_gem_object_pin_map(vma->obj, map);
> -	if (IS_ERR(addr))
> -		goto err;
> +	if (IS_ERR(addr)) {
> +		ret = PTR_ERR(addr);
> +		goto unpin_ring;
> +	}
>   
>   	vma->obj->pin_global++;
>   
>   	ring->vaddr = addr;
>   	return 0;
>   
> -err:
> +unpin_ring:
>   	i915_vma_unpin(vma);
> -	return PTR_ERR(addr);
> +unpin_timeline:
> +	i915_timeline_unpin(ring->timeline);
> +	return ret;
>   }
>   
>   void intel_ring_reset(struct intel_ring *ring, u32 tail)
> @@ -1229,6 +1270,8 @@ void intel_ring_unpin(struct intel_ring *ring)
>   
>   	ring->vma->obj->pin_global--;
>   	i915_vma_unpin(ring->vma);
> +
> +	i915_timeline_unpin(ring->timeline);
>   }
>   
>   static struct i915_vma *
> diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c
> index acd27c7e807b..b4b61056b227 100644
> --- a/drivers/gpu/drm/i915/selftests/mock_engine.c
> +++ b/drivers/gpu/drm/i915/selftests/mock_engine.c
> @@ -79,6 +79,7 @@ static void advance(struct mock_engine *engine,
>   		    struct mock_request *request)
>   {
>   	list_del_init(&request->link);
> +	i915_request_fake_complete(&request->base);
>   	mock_seqno_advance(&engine->base, request->base.global_seqno);
>   }
>   
> @@ -253,16 +254,13 @@ void mock_engine_flush(struct intel_engine_cs *engine)
>   	del_timer_sync(&mock->hw_delay);
>   
>   	spin_lock_irq(&mock->hw_lock);
> -	list_for_each_entry_safe(request, rn, &mock->hw_queue, link) {
> -		list_del_init(&request->link);
> -		mock_seqno_advance(&mock->base, request->base.global_seqno);
> -	}
> +	list_for_each_entry_safe(request, rn, &mock->hw_queue, link)
> +		advance(mock, request);
>   	spin_unlock_irq(&mock->hw_lock);
>   }
>   
>   void mock_engine_reset(struct intel_engine_cs *engine)
>   {
> -	intel_write_status_page(engine, I915_GEM_HWS_INDEX, 0);
>   }
>   
>   void mock_engine_free(struct intel_engine_cs *engine)
> 

Looks good.

Regards,

Tvrtko
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 50+ messages in thread

end of thread, other threads:[~2019-01-18 14:10 UTC | newest]

Thread overview: 50+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-01-17 14:34 Swapping a single global interrupt handler for a herd Chris Wilson
2019-01-17 14:34 ` [PATCH 01/23] drm/i915: Make all GPU resets atomic Chris Wilson
2019-01-17 14:34 ` [PATCH 02/23] drm/i915/guc: Disable global reset Chris Wilson
2019-01-17 14:34 ` [PATCH 03/23] drm/i915: Remove GPU reset dependence on struct_mutex Chris Wilson
2019-01-17 14:34 ` [PATCH 04/23] drm/i915/selftests: Trim struct_mutex duration for set-wedged selftest Chris Wilson
2019-01-17 14:34 ` [PATCH 05/23] drm/i915: Issue engine resets onto idle engines Chris Wilson
2019-01-18 12:06   ` Mika Kuoppala
2019-01-17 14:34 ` [PATCH 06/23] drm/i915: Stop tracking MRU activity on VMA Chris Wilson
2019-01-17 14:34 ` [PATCH 07/23] drm/i915: Pull VM lists under the VM mutex Chris Wilson
2019-01-18 10:07   ` Tvrtko Ursulin
2019-01-17 14:34 ` [PATCH 08/23] drm/i915: Move vma lookup to its own lock Chris Wilson
2019-01-17 16:27   ` Tvrtko Ursulin
2019-01-17 16:31     ` Chris Wilson
2019-01-17 16:36       ` Chris Wilson
2019-01-17 16:51         ` Tvrtko Ursulin
2019-01-17 16:44     ` Chris Wilson
2019-01-17 14:34 ` [PATCH 09/23] drm/i915: Use b->irq_enable() as predicate for mock engine Chris Wilson
2019-01-17 16:44   ` Tvrtko Ursulin
2019-01-17 16:52     ` Chris Wilson
2019-01-17 18:00       ` Tvrtko Ursulin
2019-01-17 14:34 ` [PATCH 10/23] drm/i915/selftests: Allocate mock ring/timeline per context Chris Wilson
2019-01-17 14:34 ` [PATCH 11/23] drm/i915/selftests: Make evict tolerant of foreign objects Chris Wilson
2019-01-17 17:29   ` Tvrtko Ursulin
2019-01-18 11:23     ` Chris Wilson
2019-01-17 14:34 ` [PATCH 12/23] drm/i915: Always allocate an object/vma for the HWSP Chris Wilson
2019-01-17 14:34 ` [PATCH 13/23] drm/i915: Move list of timelines under its own lock Chris Wilson
2019-01-17 17:54   ` Tvrtko Ursulin
2019-01-18 11:31     ` Chris Wilson
2019-01-17 14:34 ` [PATCH 14/23] drm/i915: Introduce concept of per-timeline (context) HWSP Chris Wilson
2019-01-18 10:18   ` Tvrtko Ursulin
2019-01-17 14:34 ` [PATCH 15/23] drm/i915: Enlarge vma->pin_count Chris Wilson
2019-01-17 14:34 ` [PATCH 16/23] drm/i915: Allocate a status page for each timeline Chris Wilson
2019-01-18 11:19   ` Tvrtko Ursulin
2019-01-17 14:34 ` [PATCH 17/23] drm/i915: Share per-timeline HWSP using a slab suballocator Chris Wilson
2019-01-18 12:08   ` Tvrtko Ursulin
2019-01-17 14:34 ` [PATCH 18/23] drm/i915: Keep all partially allocated HWSP on a freelist Chris Wilson
2019-01-18 12:12   ` Mika Kuoppala
2019-01-18 12:25   ` Tvrtko Ursulin
2019-01-17 14:35 ` [PATCH 19/23] drm/i915: Track the context's seqno in its own timeline HWSP Chris Wilson
2019-01-18 14:10   ` Tvrtko Ursulin
2019-01-17 14:35 ` [PATCH 20/23] drm/i915: Identify active requests Chris Wilson
2019-01-17 14:35 ` [PATCH 21/23] drm/i915: Remove the intel_engine_notify tracepoint Chris Wilson
2019-01-17 14:35 ` [PATCH 22/23] drm/i915: Replace global breadcrumbs with per-context interrupt tracking Chris Wilson
2019-01-17 14:35 ` [PATCH 23/23] drm/i915: Drop fake breadcrumb irq Chris Wilson
2019-01-17 14:37 ` Swapping a single global interrupt handler for a herd Chris Wilson
2019-01-17 14:56 ` ✗ Fi.CI.CHECKPATCH: warning for series starting with [01/23] drm/i915: Make all GPU resets atomic Patchwork
2019-01-17 15:05 ` ✗ Fi.CI.SPARSE: " Patchwork
2019-01-17 15:38 ` ✓ Fi.CI.BAT: success " Patchwork
2019-01-17 23:36 ` ✗ Fi.CI.IGT: failure " Patchwork
2019-01-17 23:41   ` Chris Wilson

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