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From: Imre Deak <imre.deak@intel.com>
To: intel-gfx@lists.freedesktop.org
Subject: [PATCH 01/10] drm/i915: Add support for tracking wakerefs w/o power-on guarantee
Date: Fri,  3 May 2019 02:26:39 +0300	[thread overview]
Message-ID: <20190502232648.4450-2-imre.deak@intel.com> (raw)
In-Reply-To: <20190502232648.4450-1-imre.deak@intel.com>

It's useful to track runtime PM refs that don't guarantee a device
power-on state to the rest of the driver. One such case is holding a
reference that will be put asynchronously, during which normal users
without their own reference shouldn't access the HW. A follow-up patch
will add support for disabling display power domains asynchronously
which needs this.

For this we can track all references with a separate wakeref_track_count
and references guaranteeing a power-on state with the current
wakeref_count.

Follow-up patches will make use of the API added here, so add a
__used__ attribute quirk to keep git bisect working.

No functional changes.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h         |   1 +
 drivers/gpu/drm/i915/intel_runtime_pm.c | 121 ++++++++++++++++++++----
 2 files changed, 102 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 9a634ba57ff9..9fb26634a6be 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1177,6 +1177,7 @@ struct skl_wm_params {
  */
 struct i915_runtime_pm {
 	atomic_t wakeref_count;
+	atomic_t wakeref_track_count;
 	bool suspended;
 	bool irqs_enabled;
 
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 30e7cb9d5801..4a7bfc945322 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -59,6 +59,12 @@
  * present for a given platform.
  */
 
+static void
+assert_raw_rpm_wakelock_held(struct drm_i915_private *i915)
+{
+	WARN_ON(!atomic_read(&i915->runtime_pm.wakeref_track_count));
+}
+
 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)
 
 #include <linux/sort.h>
@@ -100,17 +106,18 @@ static void init_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
 	struct i915_runtime_pm *rpm = &i915->runtime_pm;
 
 	spin_lock_init(&rpm->debug.lock);
+	atomic_set(&rpm->wakeref_track_count, 0);
 }
 
 static noinline depot_stack_handle_t
-track_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
+track_intel_runtime_pm_wakeref_raw(struct drm_i915_private *i915)
 {
 	struct i915_runtime_pm *rpm = &i915->runtime_pm;
 	depot_stack_handle_t stack, *stacks;
 	unsigned long flags;
 
-	atomic_inc(&rpm->wakeref_count);
-	assert_rpm_wakelock_held(i915);
+	atomic_inc(&rpm->wakeref_track_count);
+	assert_raw_rpm_wakelock_held(i915);
 
 	if (!HAS_RUNTIME_PM(i915))
 		return -1;
@@ -139,6 +146,15 @@ track_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
 	return stack;
 }
 
+static noinline depot_stack_handle_t
+track_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
+{
+	atomic_inc(&i915->runtime_pm.wakeref_count);
+	assert_rpm_wakelock_held(i915);
+
+	return track_intel_runtime_pm_wakeref_raw(i915);
+}
+
 static void cancel_intel_runtime_pm_wakeref(struct drm_i915_private *i915,
 					    depot_stack_handle_t stack)
 {
@@ -163,7 +179,7 @@ static void cancel_intel_runtime_pm_wakeref(struct drm_i915_private *i915,
 
 	if (WARN(!found,
 		 "Unmatched wakeref (tracking %lu), count %u\n",
-		 rpm->debug.count, atomic_read(&rpm->wakeref_count))) {
+		 rpm->debug.count, atomic_read(&rpm->wakeref_track_count))) {
 		char *buf;
 
 		buf = kmalloc(PAGE_SIZE, GFP_NOWAIT | __GFP_NOWARN);
@@ -235,15 +251,15 @@ __print_intel_runtime_pm_wakeref(struct drm_printer *p,
 }
 
 static noinline void
-untrack_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
+untrack_intel_runtime_pm_wakeref_raw(struct drm_i915_private *i915)
 {
 	struct i915_runtime_pm *rpm = &i915->runtime_pm;
 	struct intel_runtime_pm_debug dbg = {};
 	struct drm_printer p;
 	unsigned long flags;
 
-	assert_rpm_wakelock_held(i915);
-	if (atomic_dec_and_lock_irqsave(&rpm->wakeref_count,
+	assert_raw_rpm_wakelock_held(i915);
+	if (atomic_dec_and_lock_irqsave(&rpm->wakeref_track_count,
 					&rpm->debug.lock,
 					flags)) {
 		dbg = rpm->debug;
@@ -263,6 +279,15 @@ untrack_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
 	kfree(dbg.owners);
 }
 
+static noinline void
+untrack_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
+{
+	untrack_intel_runtime_pm_wakeref_raw(i915);
+
+	assert_rpm_wakelock_held(i915);
+	atomic_dec(&i915->runtime_pm.wakeref_count);
+}
+
 void print_intel_runtime_pm_wakeref(struct drm_i915_private *i915,
 				    struct drm_printer *p)
 {
@@ -308,15 +333,33 @@ static void init_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
 }
 
 static depot_stack_handle_t
-track_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
+track_intel_runtime_pm_wakeref_raw(struct drm_i915_private *i915)
 {
-	atomic_inc(&i915->runtime_pm.wakeref_count);
-	assert_rpm_wakelock_held(i915);
+	atomic_inc(&i915->runtime_pm.wakeref_track_count);
+	assert_raw_rpm_wakelock_held(i915);
+
 	return -1;
 }
 
+static depot_stack_handle_t
+track_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
+{
+	atomic_inc(&i915->runtime_pm.wakeref_count);
+	assert_rpm_wakelock_held(i915);
+
+	return track_intel_runtime_pm_wakeref_raw(i915);
+}
+
+static void untrack_intel_runtime_pm_wakeref_raw(struct drm_i915_private *i915)
+{
+	assert_raw_rpm_wakelock_held(i915);
+	atomic_dec(&i915->runtime_pm.wakeref_track_count);
+}
+
 static void untrack_intel_runtime_pm_wakeref(struct drm_i915_private *i915)
 {
+	untrack_intel_runtime_pm_wakeref_raw(i915);
+
 	assert_rpm_wakelock_held(i915);
 	atomic_dec(&i915->runtime_pm.wakeref_count);
 }
@@ -4347,7 +4390,7 @@ static void intel_power_domains_verify_state(struct drm_i915_private *i915)
  *
  * Returns: the wakeref cookie to pass to intel_runtime_pm_put()
  */
-intel_wakeref_t intel_runtime_pm_get(struct drm_i915_private *i915)
+static void __intel_runtime_pm_get(struct drm_i915_private *i915)
 {
 	struct pci_dev *pdev = i915->drm.pdev;
 	struct device *kdev = &pdev->dev;
@@ -4355,6 +4398,19 @@ intel_wakeref_t intel_runtime_pm_get(struct drm_i915_private *i915)
 
 	ret = pm_runtime_get_sync(kdev);
 	WARN_ONCE(ret < 0, "pm_runtime_get_sync() failed: %d\n", ret);
+}
+
+__attribute__((__used__))
+static intel_wakeref_t intel_runtime_pm_get_raw(struct drm_i915_private *i915)
+{
+	__intel_runtime_pm_get(i915);
+
+	return track_intel_runtime_pm_wakeref_raw(i915);
+}
+
+intel_wakeref_t intel_runtime_pm_get(struct drm_i915_private *i915)
+{
+	__intel_runtime_pm_get(i915);
 
 	return track_intel_runtime_pm_wakeref(i915);
 }
@@ -4430,23 +4486,48 @@ intel_wakeref_t intel_runtime_pm_get_noresume(struct drm_i915_private *i915)
  * intel_runtime_pm_get() and might power down the corresponding
  * hardware block right away if this is the last reference.
  */
+static void __intel_runtime_pm_put_unchecked(struct drm_i915_private *i915)
+{
+	struct pci_dev *pdev = i915->drm.pdev;
+	struct device *kdev = &pdev->dev;
+
+	pm_runtime_mark_last_busy(kdev);
+	pm_runtime_put_autosuspend(kdev);
+}
+
+static void intel_runtime_pm_put_unchecked_raw(struct drm_i915_private *i915)
+{
+	untrack_intel_runtime_pm_wakeref_raw(i915);
+	__intel_runtime_pm_put_unchecked(i915);
+}
+
 void intel_runtime_pm_put_unchecked(struct drm_i915_private *i915)
 {
-	struct pci_dev *pdev = i915->drm.pdev;
-	struct device *kdev = &pdev->dev;
-
 	untrack_intel_runtime_pm_wakeref(i915);
-
-	pm_runtime_mark_last_busy(kdev);
-	pm_runtime_put_autosuspend(kdev);
+	__intel_runtime_pm_put_unchecked(i915);
 }
 
 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)
+__attribute__((__used__))
+static void intel_runtime_pm_put_raw(struct drm_i915_private *i915,
+				     intel_wakeref_t wref)
+{
+	cancel_intel_runtime_pm_wakeref(i915, wref);
+	intel_runtime_pm_put_unchecked_raw(i915);
+}
+
 void intel_runtime_pm_put(struct drm_i915_private *i915, intel_wakeref_t wref)
 {
 	cancel_intel_runtime_pm_wakeref(i915, wref);
 	intel_runtime_pm_put_unchecked(i915);
 }
+#else
+__attribute__((__used__))
+static void intel_runtime_pm_put_raw(struct drm_i915_private *i915,
+				     intel_wakeref_t wref)
+{
+	intel_runtime_pm_put_unchecked_raw(i915);
+}
 #endif
 
 /**
@@ -4521,12 +4602,12 @@ void intel_runtime_pm_cleanup(struct drm_i915_private *i915)
 	struct i915_runtime_pm *rpm = &i915->runtime_pm;
 	int count;
 
-	count = atomic_fetch_inc(&rpm->wakeref_count); /* balance untrack */
+	count = atomic_fetch_inc(&rpm->wakeref_track_count); /* balance untrack */
 	WARN(count,
-	     "i915->runtime_pm.wakeref_count=%d on cleanup\n",
+	     "i915->runtime_pm.wakeref_track_count=%d on cleanup\n",
 	     count);
 
-	untrack_intel_runtime_pm_wakeref(i915);
+	untrack_intel_runtime_pm_wakeref_raw(i915);
 }
 
 void intel_runtime_pm_init_early(struct drm_i915_private *i915)
-- 
2.17.1

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

  reply	other threads:[~2019-05-02 23:27 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-02 23:26 [PATCH 00/10] drm/i915: Add support for asynchronous display power disabling Imre Deak
2019-05-02 23:26 ` Imre Deak [this message]
2019-05-07 14:03   ` [PATCH 01/10] drm/i915: Add support for tracking wakerefs w/o power-on guarantee Chris Wilson
2019-05-02 23:26 ` [PATCH 02/10] drm/i915: Verify power domains state during suspend in all cases Imre Deak
2019-05-02 23:26 ` [PATCH 03/10] drm/i915: Add support for asynchronous display power disabling Imre Deak
2019-05-03 12:16   ` Chris Wilson
2019-05-03 13:42     ` Imre Deak
2019-05-06 11:12   ` [PATCH v2 " Imre Deak
2019-05-02 23:26 ` [PATCH 04/10] drm/i915: Disable power asynchronously during DP AUX transfers Imre Deak
2019-05-02 23:26 ` [PATCH 05/10] drm/i915: WARN for eDP encoders in intel_dp_detect_dpcd() Imre Deak
2019-05-02 23:26 ` [PATCH 06/10] drm/i915: Remove the unneeded AUX power ref from intel_dp_detect() Imre Deak
2019-05-02 23:26 ` [PATCH 07/10] drm/i915: Remove the unneeded AUX power ref from intel_dp_hpd_pulse() Imre Deak
2019-05-02 23:26 ` [PATCH 08/10] drm/i915: Replace use of PLLS power domain with DISPLAY_CORE domain Imre Deak
2019-05-02 23:26 ` [PATCH 09/10] drm/i915: Avoid taking the PPS lock for non-eDP/VLV/CHV Imre Deak
2019-05-06 12:35   ` Ville Syrjälä
2019-05-06 13:12     ` Ville Syrjälä
2019-05-06 13:15       ` Imre Deak
2019-05-02 23:26 ` [PATCH 10/10] drm/i915: Assert that TypeC ports are not used for eDP Imre Deak
2019-05-03  0:34 ` ✗ Fi.CI.CHECKPATCH: warning for drm/i915: Add support for asynchronous display power disabling Patchwork
2019-05-03  0:38 ` ✗ Fi.CI.SPARSE: " Patchwork
2019-05-03  1:12 ` ✓ Fi.CI.BAT: success " Patchwork
2019-05-03  7:50 ` ✗ Fi.CI.IGT: failure " Patchwork
2019-05-03 10:07   ` Imre Deak
2019-05-03 12:37     ` Chris Wilson
2019-05-03 13:52       ` Imre Deak
2019-05-03 14:21         ` Imre Deak
2019-05-06  9:44         ` Imre Deak
2019-05-06 11:29 ` ✗ Fi.CI.CHECKPATCH: warning for drm/i915: Add support for asynchronous display power disabling (rev2) Patchwork
2019-05-06 11:49 ` ✓ Fi.CI.BAT: success " Patchwork
2019-05-06 12:57 ` ✓ Fi.CI.IGT: " Patchwork

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