[PATCH v5 0/7] DRM scheduler changes for Xe

[PATCH v5 0/7] DRM scheduler changes for Xe

[Matthew Brost]

As a prerequisite to merging the new Intel Xe DRM driver [1] [2], we
have been asked to merge our common DRM scheduler patches first.

This a continuation of a RFC [3] with all comments addressed, ready for
a full review, and hopefully in state which can merged in the near
future. More details of this series can found in the cover letter of the
RFC [3].

These changes have been tested with the Xe driver.

v2:
 - Break run job, free job, and process message in own work items
 - This might break other drivers as run job and free job now can run in
   parallel, can fix up if needed

v3:
 - Include missing patch 'drm/sched: Add drm_sched_submit_* helpers'
 - Fix issue with setting timestamp to early
 - Don't dequeue jobs for single entity after calling entity fini
 - Flush pending jobs on entity fini
 - Add documentation for entity teardown
 - Add Matthew Brost to maintainers of DRM scheduler

v4:
 - Drop message interface
 - Drop 'Flush pending jobs on entity fini'
 - Drop 'Add documentation for entity teardown'
 - Address all feedback

v5:
 - Address Luben's feedback
 - Drop starting TDR after calling run_job()
 - Drop adding Matthew Brost to maintainers of DRM scheduler

Matt

[1] https://gitlab.freedesktop.org/drm/xe/kernel
[2] https://patchwork.freedesktop.org/series/112188/
[3] https://patchwork.freedesktop.org/series/116055/

Matthew Brost (7):
  drm/sched: Add drm_sched_wqueue_* helpers
  drm/sched: Convert drm scheduler to use a work queue rather than
    kthread
  drm/sched: Move schedule policy to scheduler
  drm/sched: Add DRM_SCHED_POLICY_SINGLE_ENTITY scheduling policy
  drm/sched: Split free_job into own work item
  drm/sched: Add drm_sched_start_timeout_unlocked helper
  drm/sched: Add helper to queue TDR immediately for current and future
    jobs

 .../drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c   |   2 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c   |  15 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c    |  15 +-
 drivers/gpu/drm/etnaviv/etnaviv_sched.c       |   5 +-
 drivers/gpu/drm/lima/lima_sched.c             |   5 +-
 drivers/gpu/drm/msm/adreno/adreno_device.c    |   6 +-
 drivers/gpu/drm/msm/msm_ringbuffer.c          |   7 +-
 drivers/gpu/drm/nouveau/nouveau_sched.c       |   5 +-
 drivers/gpu/drm/panfrost/panfrost_job.c       |   5 +-
 drivers/gpu/drm/scheduler/sched_entity.c      |  86 ++-
 drivers/gpu/drm/scheduler/sched_fence.c       |   2 +-
 drivers/gpu/drm/scheduler/sched_main.c        | 506 ++++++++++++------
 drivers/gpu/drm/v3d/v3d_sched.c               |  25 +-
 include/drm/gpu_scheduler.h                   |  48 +-
 14 files changed, 499 insertions(+), 233 deletions(-)

-- 
2.34.1

[PATCH v5 1/7] drm/sched: Add drm_sched_wqueue_* helpers

[Matthew Brost]

Add scheduler wqueue ready, stop, and start helpers to hide the
implementation details of the scheduler from the drivers.

v2:
  - s/sched_wqueue/sched_wqueue (Luben)
  - Remove the extra white line after the return-statement (Luben)
  - update drm_sched_wqueue_ready comment (Luben)

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Cc: Luben Tuikov <luben.tuikov@amd.com>
---
 .../drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c   |  2 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c   | 15 +++----
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c    | 12 +++---
 drivers/gpu/drm/msm/adreno/adreno_device.c    |  6 ++-
 drivers/gpu/drm/scheduler/sched_main.c        | 39 ++++++++++++++++++-
 include/drm/gpu_scheduler.h                   |  3 ++
 6 files changed, 59 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c
index 625db444df1c..10d56979fe3b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c
@@ -290,7 +290,7 @@ static int suspend_resume_compute_scheduler(struct amdgpu_device *adev, bool sus
 	for (i = 0; i < adev->gfx.num_compute_rings; i++) {
 		struct amdgpu_ring *ring = &adev->gfx.compute_ring[i];
 
-		if (!(ring && ring->sched.thread))
+		if (!(ring && drm_sched_wqueue_ready(&ring->sched)))
 			continue;
 
 		/* stop secheduler and drain ring. */
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index a4faea4fa0b5..a4c0bb358db7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -1659,9 +1659,9 @@ static int amdgpu_debugfs_test_ib_show(struct seq_file *m, void *unused)
 	for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
 		struct amdgpu_ring *ring = adev->rings[i];
 
-		if (!ring || !ring->sched.thread)
+		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
 			continue;
-		kthread_park(ring->sched.thread);
+		drm_sched_wqueue_stop(&ring->sched);
 	}
 
 	seq_puts(m, "run ib test:\n");
@@ -1675,9 +1675,9 @@ static int amdgpu_debugfs_test_ib_show(struct seq_file *m, void *unused)
 	for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
 		struct amdgpu_ring *ring = adev->rings[i];
 
-		if (!ring || !ring->sched.thread)
+		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
 			continue;
-		kthread_unpark(ring->sched.thread);
+		drm_sched_wqueue_start(&ring->sched);
 	}
 
 	up_write(&adev->reset_domain->sem);
@@ -1897,7 +1897,8 @@ static int amdgpu_debugfs_ib_preempt(void *data, u64 val)
 
 	ring = adev->rings[val];
 
-	if (!ring || !ring->funcs->preempt_ib || !ring->sched.thread)
+	if (!ring || !ring->funcs->preempt_ib ||
+	    !drm_sched_wqueue_ready(&ring->sched))
 		return -EINVAL;
 
 	/* the last preemption failed */
@@ -1915,7 +1916,7 @@ static int amdgpu_debugfs_ib_preempt(void *data, u64 val)
 		goto pro_end;
 
 	/* stop the scheduler */
-	kthread_park(ring->sched.thread);
+	drm_sched_wqueue_stop(&ring->sched);
 
 	/* preempt the IB */
 	r = amdgpu_ring_preempt_ib(ring);
@@ -1949,7 +1950,7 @@ static int amdgpu_debugfs_ib_preempt(void *data, u64 val)
 
 failure:
 	/* restart the scheduler */
-	kthread_unpark(ring->sched.thread);
+	drm_sched_wqueue_start(&ring->sched);
 
 	up_read(&adev->reset_domain->sem);
 
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 2b8356699f23..b1aafe815f28 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -4588,7 +4588,7 @@ bool amdgpu_device_has_job_running(struct amdgpu_device *adev)
 	for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 		struct amdgpu_ring *ring = adev->rings[i];
 
-		if (!ring || !ring->sched.thread)
+		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
 			continue;
 
 		spin_lock(&ring->sched.job_list_lock);
@@ -4727,7 +4727,7 @@ int amdgpu_device_pre_asic_reset(struct amdgpu_device *adev,
 	for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 		struct amdgpu_ring *ring = adev->rings[i];
 
-		if (!ring || !ring->sched.thread)
+		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
 			continue;
 
 		/* Clear job fence from fence drv to avoid force_completion
@@ -5266,7 +5266,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
 		for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 			struct amdgpu_ring *ring = tmp_adev->rings[i];
 
-			if (!ring || !ring->sched.thread)
+			if (!ring || !drm_sched_wqueue_ready(&ring->sched))
 				continue;
 
 			drm_sched_stop(&ring->sched, job ? &job->base : NULL);
@@ -5341,7 +5341,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
 		for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 			struct amdgpu_ring *ring = tmp_adev->rings[i];
 
-			if (!ring || !ring->sched.thread)
+			if (!ring || !drm_sched_wqueue_ready(&ring->sched))
 				continue;
 
 			drm_sched_start(&ring->sched, true);
@@ -5667,7 +5667,7 @@ pci_ers_result_t amdgpu_pci_error_detected(struct pci_dev *pdev, pci_channel_sta
 		for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 			struct amdgpu_ring *ring = adev->rings[i];
 
-			if (!ring || !ring->sched.thread)
+			if (!ring || !drm_sched_wqueue_ready(&ring->sched))
 				continue;
 
 			drm_sched_stop(&ring->sched, NULL);
@@ -5795,7 +5795,7 @@ void amdgpu_pci_resume(struct pci_dev *pdev)
 	for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 		struct amdgpu_ring *ring = adev->rings[i];
 
-		if (!ring || !ring->sched.thread)
+		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
 			continue;
 
 		drm_sched_start(&ring->sched, true);
diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm/msm/adreno/adreno_device.c
index fa527935ffd4..8fa9ce3746b6 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_device.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
@@ -809,7 +809,8 @@ static void suspend_scheduler(struct msm_gpu *gpu)
 	 */
 	for (i = 0; i < gpu->nr_rings; i++) {
 		struct drm_gpu_scheduler *sched = &gpu->rb[i]->sched;
-		kthread_park(sched->thread);
+
+		drm_sched_wqueue_stop(sched);
 	}
 }
 
@@ -819,7 +820,8 @@ static void resume_scheduler(struct msm_gpu *gpu)
 
 	for (i = 0; i < gpu->nr_rings; i++) {
 		struct drm_gpu_scheduler *sched = &gpu->rb[i]->sched;
-		kthread_unpark(sched->thread);
+
+		drm_sched_wqueue_start(sched);
 	}
 }
 
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 5a3a622fc672..6f2f7dd4ba0a 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -439,7 +439,7 @@ void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad)
 {
 	struct drm_sched_job *s_job, *tmp;
 
-	kthread_park(sched->thread);
+	drm_sched_wqueue_stop(sched);
 
 	/*
 	 * Reinsert back the bad job here - now it's safe as
@@ -552,7 +552,7 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
 		spin_unlock(&sched->job_list_lock);
 	}
 
-	kthread_unpark(sched->thread);
+	drm_sched_wqueue_start(sched);
 }
 EXPORT_SYMBOL(drm_sched_start);
 
@@ -1206,3 +1206,38 @@ void drm_sched_increase_karma(struct drm_sched_job *bad)
 	}
 }
 EXPORT_SYMBOL(drm_sched_increase_karma);
+
+/**
+ * drm_sched_wqueue_ready - Is the scheduler ready for submission
+ *
+ * @sched: scheduler instance
+ *
+ * Returns true if submission is ready
+ */
+bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched)
+{
+	return !!sched->thread;
+}
+EXPORT_SYMBOL(drm_sched_wqueue_ready);
+
+/**
+ * drm_sched_wqueue_stop - stop scheduler submission
+ *
+ * @sched: scheduler instance
+ */
+void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched)
+{
+	kthread_park(sched->thread);
+}
+EXPORT_SYMBOL(drm_sched_wqueue_stop);
+
+/**
+ * drm_sched_wqueue_start - start scheduler submission
+ *
+ * @sched: scheduler instance
+ */
+void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched)
+{
+	kthread_unpark(sched->thread);
+}
+EXPORT_SYMBOL(drm_sched_wqueue_start);
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index f9544d9b670d..38578fe74573 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -550,6 +550,9 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
 
 void drm_sched_job_cleanup(struct drm_sched_job *job);
 void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched);
+bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched);
+void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched);
+void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched);
 void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad);
 void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery);
 void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched);
-- 
2.34.1

[PATCH v5 2/7] drm/sched: Convert drm scheduler to use a work queue rather than kthread

[Matthew Brost]

In Xe, the new Intel GPU driver, a choice has made to have a 1 to 1
mapping between a drm_gpu_scheduler and drm_sched_entity. At first this
seems a bit odd but let us explain the reasoning below.

1. In Xe the submission order from multiple drm_sched_entity is not
guaranteed to be the same completion even if targeting the same hardware
engine. This is because in Xe we have a firmware scheduler, the GuC,
which allowed to reorder, timeslice, and preempt submissions. If a using
shared drm_gpu_scheduler across multiple drm_sched_entity, the TDR falls
apart as the TDR expects submission order == completion order. Using a
dedicated drm_gpu_scheduler per drm_sched_entity solve this problem.

2. In Xe submissions are done via programming a ring buffer (circular
buffer), a drm_gpu_scheduler provides a limit on number of jobs, if the
limit of number jobs is set to RING_SIZE / MAX_SIZE_PER_JOB we get flow
control on the ring for free.

A problem with this design is currently a drm_gpu_scheduler uses a
kthread for submission / job cleanup. This doesn't scale if a large
number of drm_gpu_scheduler are used. To work around the scaling issue,
use a worker rather than kthread for submission / job cleanup.

v2:
  - (Rob Clark) Fix msm build
  - Pass in run work queue
v3:
  - (Boris) don't have loop in worker
v4:
  - (Tvrtko) break out submit ready, stop, start helpers into own patch
v5:
  - (Boris) default to ordered work queue
v6:
  - (Luben / checkpatch) fix alignment in msm_ringbuffer.c
  - (Luben) s/drm_sched_submit_queue/drm_sched_wqueue_enqueue
  - (Luben) Update comment for drm_sched_wqueue_enqueue
  - (Luben) Positive check for submit_wq in drm_sched_init
  - (Luben) s/alloc_submit_wq/own_submit_wq

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |   2 +-
 drivers/gpu/drm/etnaviv/etnaviv_sched.c    |   2 +-
 drivers/gpu/drm/lima/lima_sched.c          |   2 +-
 drivers/gpu/drm/msm/msm_ringbuffer.c       |   7 +-
 drivers/gpu/drm/nouveau/nouveau_sched.c    |   2 +-
 drivers/gpu/drm/panfrost/panfrost_job.c    |   2 +-
 drivers/gpu/drm/scheduler/sched_main.c     | 118 ++++++++++-----------
 drivers/gpu/drm/v3d/v3d_sched.c            |  10 +-
 include/drm/gpu_scheduler.h                |  14 ++-
 9 files changed, 82 insertions(+), 77 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index b1aafe815f28..b54c4d771104 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -2279,7 +2279,7 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
 			break;
 		}
 
-		r = drm_sched_init(&ring->sched, &amdgpu_sched_ops,
+		r = drm_sched_init(&ring->sched, &amdgpu_sched_ops, NULL,
 				   ring->num_hw_submission, 0,
 				   timeout, adev->reset_domain->wq,
 				   ring->sched_score, ring->name,
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
index 345fec6cb1a4..618a804ddc34 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
@@ -134,7 +134,7 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
 {
 	int ret;
 
-	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops,
+	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops, NULL,
 			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
 			     msecs_to_jiffies(500), NULL, NULL,
 			     dev_name(gpu->dev), gpu->dev);
diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
index ffd91a5ee299..8d858aed0e56 100644
--- a/drivers/gpu/drm/lima/lima_sched.c
+++ b/drivers/gpu/drm/lima/lima_sched.c
@@ -488,7 +488,7 @@ int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
 
 	INIT_WORK(&pipe->recover_work, lima_sched_recover_work);
 
-	return drm_sched_init(&pipe->base, &lima_sched_ops, 1,
+	return drm_sched_init(&pipe->base, &lima_sched_ops, NULL, 1,
 			      lima_job_hang_limit,
 			      msecs_to_jiffies(timeout), NULL,
 			      NULL, name, pipe->ldev->dev);
diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
index 40c0bc35a44c..1097f8e93d6b 100644
--- a/drivers/gpu/drm/msm/msm_ringbuffer.c
+++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
@@ -94,9 +94,10 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
 	 /* currently managing hangcheck ourselves: */
 	sched_timeout = MAX_SCHEDULE_TIMEOUT;
 
-	ret = drm_sched_init(&ring->sched, &msm_sched_ops,
-			num_hw_submissions, 0, sched_timeout,
-			NULL, NULL, to_msm_bo(ring->bo)->name, gpu->dev->dev);
+	ret = drm_sched_init(&ring->sched, &msm_sched_ops, NULL,
+			     num_hw_submissions, 0, sched_timeout,
+			     NULL, NULL, to_msm_bo(ring->bo)->name,
+			     gpu->dev->dev);
 	if (ret) {
 		goto fail;
 	}
diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
index 3b7ea5221226..4c959dec42b3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_sched.c
+++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
@@ -435,7 +435,7 @@ int nouveau_sched_init(struct nouveau_drm *drm)
 	if (!drm->sched_wq)
 		return -ENOMEM;
 
-	return drm_sched_init(sched, &nouveau_sched_ops,
+	return drm_sched_init(sched, &nouveau_sched_ops, NULL,
 			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
 			      NULL, NULL, "nouveau_sched", drm->dev->dev);
 }
diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
index fb16de2d0420..934b7b930c76 100644
--- a/drivers/gpu/drm/panfrost/panfrost_job.c
+++ b/drivers/gpu/drm/panfrost/panfrost_job.c
@@ -852,7 +852,7 @@ int panfrost_job_init(struct panfrost_device *pfdev)
 		js->queue[j].fence_context = dma_fence_context_alloc(1);
 
 		ret = drm_sched_init(&js->queue[j].sched,
-				     &panfrost_sched_ops,
+				     &panfrost_sched_ops, NULL,
 				     nentries, 0,
 				     msecs_to_jiffies(JOB_TIMEOUT_MS),
 				     pfdev->reset.wq,
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 6f2f7dd4ba0a..8b1d52cff1e9 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -48,7 +48,6 @@
  * through the jobs entity pointer.
  */
 
-#include <linux/kthread.h>
 #include <linux/wait.h>
 #include <linux/sched.h>
 #include <linux/completion.h>
@@ -256,6 +255,16 @@ drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
 	return rb ? rb_entry(rb, struct drm_sched_entity, rb_tree_node) : NULL;
 }
 
+/**
+ * drm_sched_wqueue_enqueue - enqueue scheduler submission
+ * @sched: scheduler instance
+ */
+static void drm_sched_wqueue_enqueue(struct drm_gpu_scheduler *sched)
+{
+	if (!READ_ONCE(sched->pause_submit))
+		queue_work(sched->submit_wq, &sched->work_submit);
+}
+
 /**
  * drm_sched_job_done - complete a job
  * @s_job: pointer to the job which is done
@@ -275,7 +284,7 @@ static void drm_sched_job_done(struct drm_sched_job *s_job, int result)
 	dma_fence_get(&s_fence->finished);
 	drm_sched_fence_finished(s_fence, result);
 	dma_fence_put(&s_fence->finished);
-	wake_up_interruptible(&sched->wake_up_worker);
+	drm_sched_wqueue_enqueue(sched);
 }
 
 /**
@@ -868,7 +877,7 @@ static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
 void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched)
 {
 	if (drm_sched_can_queue(sched))
-		wake_up_interruptible(&sched->wake_up_worker);
+		drm_sched_wqueue_enqueue(sched);
 }
 
 /**
@@ -978,61 +987,42 @@ drm_sched_pick_best(struct drm_gpu_scheduler **sched_list,
 }
 EXPORT_SYMBOL(drm_sched_pick_best);
 
-/**
- * drm_sched_blocked - check if the scheduler is blocked
- *
- * @sched: scheduler instance
- *
- * Returns true if blocked, otherwise false.
- */
-static bool drm_sched_blocked(struct drm_gpu_scheduler *sched)
-{
-	if (kthread_should_park()) {
-		kthread_parkme();
-		return true;
-	}
-
-	return false;
-}
-
 /**
  * drm_sched_main - main scheduler thread
  *
  * @param: scheduler instance
- *
- * Returns 0.
  */
-static int drm_sched_main(void *param)
+static void drm_sched_main(struct work_struct *w)
 {
-	struct drm_gpu_scheduler *sched = (struct drm_gpu_scheduler *)param;
+	struct drm_gpu_scheduler *sched =
+		container_of(w, struct drm_gpu_scheduler, work_submit);
+	struct drm_sched_entity *entity;
+	struct drm_sched_job *cleanup_job;
 	int r;
 
-	sched_set_fifo_low(current);
+	if (READ_ONCE(sched->pause_submit))
+		return;
 
-	while (!kthread_should_stop()) {
-		struct drm_sched_entity *entity = NULL;
-		struct drm_sched_fence *s_fence;
-		struct drm_sched_job *sched_job;
-		struct dma_fence *fence;
-		struct drm_sched_job *cleanup_job = NULL;
+	cleanup_job = drm_sched_get_cleanup_job(sched);
+	entity = drm_sched_select_entity(sched);
 
-		wait_event_interruptible(sched->wake_up_worker,
-					 (cleanup_job = drm_sched_get_cleanup_job(sched)) ||
-					 (!drm_sched_blocked(sched) &&
-					  (entity = drm_sched_select_entity(sched))) ||
-					 kthread_should_stop());
+	if (!entity && !cleanup_job)
+		return;	/* No more work */
 
-		if (cleanup_job)
-			sched->ops->free_job(cleanup_job);
+	if (cleanup_job)
+		sched->ops->free_job(cleanup_job);
 
-		if (!entity)
-			continue;
+	if (entity) {
+		struct dma_fence *fence;
+		struct drm_sched_fence *s_fence;
+		struct drm_sched_job *sched_job;
 
 		sched_job = drm_sched_entity_pop_job(entity);
-
 		if (!sched_job) {
 			complete_all(&entity->entity_idle);
-			continue;
+			if (!cleanup_job)
+				return;	/* No more work */
+			goto again;
 		}
 
 		s_fence = sched_job->s_fence;
@@ -1063,7 +1053,9 @@ static int drm_sched_main(void *param)
 
 		wake_up(&sched->job_scheduled);
 	}
-	return 0;
+
+again:
+	drm_sched_wqueue_enqueue(sched);
 }
 
 /**
@@ -1071,6 +1063,8 @@ static int drm_sched_main(void *param)
  *
  * @sched: scheduler instance
  * @ops: backend operations for this scheduler
+ * @submit_wq: workqueue to use for submission. If NULL, an ordered wq is
+ *	       allocated and used
  * @hw_submission: number of hw submissions that can be in flight
  * @hang_limit: number of times to allow a job to hang before dropping it
  * @timeout: timeout value in jiffies for the scheduler
@@ -1084,14 +1078,25 @@ static int drm_sched_main(void *param)
  */
 int drm_sched_init(struct drm_gpu_scheduler *sched,
 		   const struct drm_sched_backend_ops *ops,
+		   struct workqueue_struct *submit_wq,
 		   unsigned hw_submission, unsigned hang_limit,
 		   long timeout, struct workqueue_struct *timeout_wq,
 		   atomic_t *score, const char *name, struct device *dev)
 {
-	int i, ret;
+	int i;
 	sched->ops = ops;
 	sched->hw_submission_limit = hw_submission;
 	sched->name = name;
+	if (submit_wq) {
+		sched->submit_wq = submit_wq;
+		sched->own_submit_wq = false;
+	} else {
+		sched->submit_wq = alloc_ordered_workqueue(name, 0);
+		if (!sched->submit_wq)
+			return -ENOMEM;
+
+		sched->own_submit_wq = true;
+	}
 	sched->timeout = timeout;
 	sched->timeout_wq = timeout_wq ? : system_wq;
 	sched->hang_limit = hang_limit;
@@ -1100,23 +1105,15 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
 	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
 		drm_sched_rq_init(sched, &sched->sched_rq[i]);
 
-	init_waitqueue_head(&sched->wake_up_worker);
 	init_waitqueue_head(&sched->job_scheduled);
 	INIT_LIST_HEAD(&sched->pending_list);
 	spin_lock_init(&sched->job_list_lock);
 	atomic_set(&sched->hw_rq_count, 0);
 	INIT_DELAYED_WORK(&sched->work_tdr, drm_sched_job_timedout);
+	INIT_WORK(&sched->work_submit, drm_sched_main);
 	atomic_set(&sched->_score, 0);
 	atomic64_set(&sched->job_id_count, 0);
-
-	/* Each scheduler will run on a seperate kernel thread */
-	sched->thread = kthread_run(drm_sched_main, sched, sched->name);
-	if (IS_ERR(sched->thread)) {
-		ret = PTR_ERR(sched->thread);
-		sched->thread = NULL;
-		DRM_DEV_ERROR(sched->dev, "Failed to create scheduler for %s.\n", name);
-		return ret;
-	}
+	sched->pause_submit = false;
 
 	sched->ready = true;
 	return 0;
@@ -1135,8 +1132,7 @@ void drm_sched_fini(struct drm_gpu_scheduler *sched)
 	struct drm_sched_entity *s_entity;
 	int i;
 
-	if (sched->thread)
-		kthread_stop(sched->thread);
+	drm_sched_wqueue_stop(sched);
 
 	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
 		struct drm_sched_rq *rq = &sched->sched_rq[i];
@@ -1159,6 +1155,8 @@ void drm_sched_fini(struct drm_gpu_scheduler *sched)
 	/* Confirm no work left behind accessing device structures */
 	cancel_delayed_work_sync(&sched->work_tdr);
 
+	if (sched->own_submit_wq)
+		destroy_workqueue(sched->submit_wq);
 	sched->ready = false;
 }
 EXPORT_SYMBOL(drm_sched_fini);
@@ -1216,7 +1214,7 @@ EXPORT_SYMBOL(drm_sched_increase_karma);
  */
 bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched)
 {
-	return !!sched->thread;
+	return sched->ready;
 }
 EXPORT_SYMBOL(drm_sched_wqueue_ready);
 
@@ -1227,7 +1225,8 @@ EXPORT_SYMBOL(drm_sched_wqueue_ready);
  */
 void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched)
 {
-	kthread_park(sched->thread);
+	WRITE_ONCE(sched->pause_submit, true);
+	cancel_work_sync(&sched->work_submit);
 }
 EXPORT_SYMBOL(drm_sched_wqueue_stop);
 
@@ -1238,6 +1237,7 @@ EXPORT_SYMBOL(drm_sched_wqueue_stop);
  */
 void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched)
 {
-	kthread_unpark(sched->thread);
+	WRITE_ONCE(sched->pause_submit, false);
+	queue_work(sched->submit_wq, &sched->work_submit);
 }
 EXPORT_SYMBOL(drm_sched_wqueue_start);
diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
index 06238e6d7f5c..38e092ea41e6 100644
--- a/drivers/gpu/drm/v3d/v3d_sched.c
+++ b/drivers/gpu/drm/v3d/v3d_sched.c
@@ -388,7 +388,7 @@ v3d_sched_init(struct v3d_dev *v3d)
 	int ret;
 
 	ret = drm_sched_init(&v3d->queue[V3D_BIN].sched,
-			     &v3d_bin_sched_ops,
+			     &v3d_bin_sched_ops, NULL,
 			     hw_jobs_limit, job_hang_limit,
 			     msecs_to_jiffies(hang_limit_ms), NULL,
 			     NULL, "v3d_bin", v3d->drm.dev);
@@ -396,7 +396,7 @@ v3d_sched_init(struct v3d_dev *v3d)
 		return ret;
 
 	ret = drm_sched_init(&v3d->queue[V3D_RENDER].sched,
-			     &v3d_render_sched_ops,
+			     &v3d_render_sched_ops, NULL,
 			     hw_jobs_limit, job_hang_limit,
 			     msecs_to_jiffies(hang_limit_ms), NULL,
 			     NULL, "v3d_render", v3d->drm.dev);
@@ -404,7 +404,7 @@ v3d_sched_init(struct v3d_dev *v3d)
 		goto fail;
 
 	ret = drm_sched_init(&v3d->queue[V3D_TFU].sched,
-			     &v3d_tfu_sched_ops,
+			     &v3d_tfu_sched_ops, NULL,
 			     hw_jobs_limit, job_hang_limit,
 			     msecs_to_jiffies(hang_limit_ms), NULL,
 			     NULL, "v3d_tfu", v3d->drm.dev);
@@ -413,7 +413,7 @@ v3d_sched_init(struct v3d_dev *v3d)
 
 	if (v3d_has_csd(v3d)) {
 		ret = drm_sched_init(&v3d->queue[V3D_CSD].sched,
-				     &v3d_csd_sched_ops,
+				     &v3d_csd_sched_ops, NULL,
 				     hw_jobs_limit, job_hang_limit,
 				     msecs_to_jiffies(hang_limit_ms), NULL,
 				     NULL, "v3d_csd", v3d->drm.dev);
@@ -421,7 +421,7 @@ v3d_sched_init(struct v3d_dev *v3d)
 			goto fail;
 
 		ret = drm_sched_init(&v3d->queue[V3D_CACHE_CLEAN].sched,
-				     &v3d_cache_clean_sched_ops,
+				     &v3d_cache_clean_sched_ops, NULL,
 				     hw_jobs_limit, job_hang_limit,
 				     msecs_to_jiffies(hang_limit_ms), NULL,
 				     NULL, "v3d_cache_clean", v3d->drm.dev);
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 38578fe74573..211bd3cdabdc 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -473,17 +473,16 @@ struct drm_sched_backend_ops {
  * @timeout: the time after which a job is removed from the scheduler.
  * @name: name of the ring for which this scheduler is being used.
  * @sched_rq: priority wise array of run queues.
- * @wake_up_worker: the wait queue on which the scheduler sleeps until a job
- *                  is ready to be scheduled.
  * @job_scheduled: once @drm_sched_entity_do_release is called the scheduler
  *                 waits on this wait queue until all the scheduled jobs are
  *                 finished.
  * @hw_rq_count: the number of jobs currently in the hardware queue.
  * @job_id_count: used to assign unique id to the each job.
+ * @submit_wq: workqueue used to queue @work_submit
  * @timeout_wq: workqueue used to queue @work_tdr
+ * @work_submit: schedules jobs and cleans up entities
  * @work_tdr: schedules a delayed call to @drm_sched_job_timedout after the
  *            timeout interval is over.
- * @thread: the kthread on which the scheduler which run.
  * @pending_list: the list of jobs which are currently in the job queue.
  * @job_list_lock: lock to protect the pending_list.
  * @hang_limit: once the hangs by a job crosses this limit then it is marked
@@ -492,6 +491,8 @@ struct drm_sched_backend_ops {
  * @_score: score used when the driver doesn't provide one
  * @ready: marks if the underlying HW is ready to work
  * @free_guilty: A hit to time out handler to free the guilty job.
+ * @pause_submit: pause queuing of @work_submit on @submit_wq
+ * @own_submit_wq: scheduler owns allocation of @submit_wq
  * @dev: system &struct device
  *
  * One scheduler is implemented for each hardware ring.
@@ -502,13 +503,13 @@ struct drm_gpu_scheduler {
 	long				timeout;
 	const char			*name;
 	struct drm_sched_rq		sched_rq[DRM_SCHED_PRIORITY_COUNT];
-	wait_queue_head_t		wake_up_worker;
 	wait_queue_head_t		job_scheduled;
 	atomic_t			hw_rq_count;
 	atomic64_t			job_id_count;
+	struct workqueue_struct		*submit_wq;
 	struct workqueue_struct		*timeout_wq;
+	struct work_struct		work_submit;
 	struct delayed_work		work_tdr;
-	struct task_struct		*thread;
 	struct list_head		pending_list;
 	spinlock_t			job_list_lock;
 	int				hang_limit;
@@ -516,11 +517,14 @@ struct drm_gpu_scheduler {
 	atomic_t                        _score;
 	bool				ready;
 	bool				free_guilty;
+	bool				pause_submit;
+	bool				own_submit_wq;
 	struct device			*dev;
 };
 
 int drm_sched_init(struct drm_gpu_scheduler *sched,
 		   const struct drm_sched_backend_ops *ops,
+		   struct workqueue_struct *submit_wq,
 		   uint32_t hw_submission, unsigned hang_limit,
 		   long timeout, struct workqueue_struct *timeout_wq,
 		   atomic_t *score, const char *name, struct device *dev);
-- 
2.34.1

[PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Matthew Brost]

Rather than a global modparam for scheduling policy, move the scheduling
policy to scheduler so user can control each scheduler policy.

v2:
  - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
  - Only include policy in scheduler (Luben)
v3:
  - use a ternary operator as opposed to an if-control (Luben)
  - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
  - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
  - Update commit message (Boris)
  - Fix v3d build (CI)
  - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
  - Don't update modparam doc (Luben)
v4:
  - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)

Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  1 +
 drivers/gpu/drm/etnaviv/etnaviv_sched.c    |  3 ++-
 drivers/gpu/drm/lima/lima_sched.c          |  3 ++-
 drivers/gpu/drm/msm/msm_ringbuffer.c       |  2 +-
 drivers/gpu/drm/nouveau/nouveau_sched.c    |  3 ++-
 drivers/gpu/drm/panfrost/panfrost_job.c    |  3 ++-
 drivers/gpu/drm/scheduler/sched_entity.c   | 24 ++++++++++++++++++----
 drivers/gpu/drm/scheduler/sched_main.c     | 19 ++++++++++++-----
 drivers/gpu/drm/v3d/v3d_sched.c            | 15 +++++++++-----
 include/drm/gpu_scheduler.h                | 20 ++++++++++++------
 10 files changed, 68 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index b54c4d771104..e4e6f91450a4 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -2283,6 +2283,7 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
 				   ring->num_hw_submission, 0,
 				   timeout, adev->reset_domain->wq,
 				   ring->sched_score, ring->name,
+				   DRM_SCHED_POLICY_UNSET,
 				   adev->dev);
 		if (r) {
 			DRM_ERROR("Failed to create scheduler on ring %s.\n",
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
index 618a804ddc34..15b0e2f1abe5 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
@@ -137,7 +137,8 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
 	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops, NULL,
 			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
 			     msecs_to_jiffies(500), NULL, NULL,
-			     dev_name(gpu->dev), gpu->dev);
+			     dev_name(gpu->dev), DRM_SCHED_POLICY_UNSET,
+			     gpu->dev);
 	if (ret)
 		return ret;
 
diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
index 8d858aed0e56..50c2075228aa 100644
--- a/drivers/gpu/drm/lima/lima_sched.c
+++ b/drivers/gpu/drm/lima/lima_sched.c
@@ -491,7 +491,8 @@ int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
 	return drm_sched_init(&pipe->base, &lima_sched_ops, NULL, 1,
 			      lima_job_hang_limit,
 			      msecs_to_jiffies(timeout), NULL,
-			      NULL, name, pipe->ldev->dev);
+			      NULL, name, DRM_SCHED_POLICY_UNSET,
+			      pipe->ldev->dev);
 }
 
 void lima_sched_pipe_fini(struct lima_sched_pipe *pipe)
diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
index 1097f8e93d6b..173ad2f17c50 100644
--- a/drivers/gpu/drm/msm/msm_ringbuffer.c
+++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
@@ -97,7 +97,7 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
 	ret = drm_sched_init(&ring->sched, &msm_sched_ops, NULL,
 			     num_hw_submissions, 0, sched_timeout,
 			     NULL, NULL, to_msm_bo(ring->bo)->name,
-			     gpu->dev->dev);
+			     DRM_SCHED_POLICY_UNSET, gpu->dev->dev);
 	if (ret) {
 		goto fail;
 	}
diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
index 4c959dec42b3..c4e09d2e77f9 100644
--- a/drivers/gpu/drm/nouveau/nouveau_sched.c
+++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
@@ -437,7 +437,8 @@ int nouveau_sched_init(struct nouveau_drm *drm)
 
 	return drm_sched_init(sched, &nouveau_sched_ops, NULL,
 			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
-			      NULL, NULL, "nouveau_sched", drm->dev->dev);
+			      NULL, NULL, "nouveau_sched",
+			      DRM_SCHED_POLICY_UNSET, drm->dev->dev);
 }
 
 void nouveau_sched_fini(struct nouveau_drm *drm)
diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
index 934b7b930c76..95330ff402ba 100644
--- a/drivers/gpu/drm/panfrost/panfrost_job.c
+++ b/drivers/gpu/drm/panfrost/panfrost_job.c
@@ -856,7 +856,8 @@ int panfrost_job_init(struct panfrost_device *pfdev)
 				     nentries, 0,
 				     msecs_to_jiffies(JOB_TIMEOUT_MS),
 				     pfdev->reset.wq,
-				     NULL, "pan_js", pfdev->dev);
+				     NULL, "pan_js", DRM_SCHED_POLICY_UNSET,
+				     pfdev->dev);
 		if (ret) {
 			dev_err(pfdev->dev, "Failed to create scheduler: %d.", ret);
 			goto err_sched;
diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index a42763e1429d..cf42e2265d64 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -33,6 +33,20 @@
 #define to_drm_sched_job(sched_job)		\
 		container_of((sched_job), struct drm_sched_job, queue_node)
 
+static bool drm_sched_policy_mismatch(struct drm_gpu_scheduler **sched_list,
+				      unsigned int num_sched_list)
+{
+	enum drm_sched_policy sched_policy = sched_list[0]->sched_policy;
+	unsigned int i;
+
+	/* All schedule policies must match */
+	for (i = 1; i < num_sched_list; ++i)
+		if (sched_policy != sched_list[i]->sched_policy)
+			return true;
+
+	return false;
+}
+
 /**
  * drm_sched_entity_init - Init a context entity used by scheduler when
  * submit to HW ring.
@@ -62,7 +76,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
 			  unsigned int num_sched_list,
 			  atomic_t *guilty)
 {
-	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])))
+	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])) ||
+	    drm_sched_policy_mismatch(sched_list, num_sched_list))
 		return -EINVAL;
 
 	memset(entity, 0, sizeof(struct drm_sched_entity));
@@ -486,7 +501,7 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
 	 * Update the entity's location in the min heap according to
 	 * the timestamp of the next job, if any.
 	 */
-	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) {
+	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
 		struct drm_sched_job *next;
 
 		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
@@ -558,7 +573,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
 void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
 {
 	struct drm_sched_entity *entity = sched_job->entity;
-	bool first;
+	bool first, fifo = entity->rq->sched->sched_policy ==
+		DRM_SCHED_POLICY_FIFO;
 	ktime_t submit_ts;
 
 	trace_drm_sched_job(sched_job, entity);
@@ -587,7 +603,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
 		drm_sched_rq_add_entity(entity->rq, entity);
 		spin_unlock(&entity->rq_lock);
 
-		if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
+		if (fifo)
 			drm_sched_rq_update_fifo(entity, submit_ts);
 
 		drm_sched_wakeup_if_can_queue(entity->rq->sched);
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 8b1d52cff1e9..150e5330f0fa 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -66,14 +66,14 @@
 #define to_drm_sched_job(sched_job)		\
 		container_of((sched_job), struct drm_sched_job, queue_node)
 
-int drm_sched_policy = DRM_SCHED_POLICY_FIFO;
+int drm_sched_policy_default = DRM_SCHED_POLICY_FIFO;
 
 /**
  * DOC: sched_policy (int)
  * Used to override default entities scheduling policy in a run queue.
  */
 MODULE_PARM_DESC(sched_policy, "Specify the scheduling policy for entities on a run-queue, " __stringify(DRM_SCHED_POLICY_RR) " = Round Robin, " __stringify(DRM_SCHED_POLICY_FIFO) " = FIFO (default).");
-module_param_named(sched_policy, drm_sched_policy, int, 0444);
+module_param_named(sched_policy, drm_sched_policy_default, int, 0444);
 
 static __always_inline bool drm_sched_entity_compare_before(struct rb_node *a,
 							    const struct rb_node *b)
@@ -177,7 +177,7 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
 	if (rq->current_entity == entity)
 		rq->current_entity = NULL;
 
-	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
+	if (rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO)
 		drm_sched_rq_remove_fifo_locked(entity);
 
 	spin_unlock(&rq->lock);
@@ -898,7 +898,7 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
 
 	/* Kernel run queue has higher priority than normal run queue*/
 	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
-		entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
+		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
 			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i]) :
 			drm_sched_rq_select_entity_rr(&sched->sched_rq[i]);
 		if (entity)
@@ -1072,6 +1072,7 @@ static void drm_sched_main(struct work_struct *w)
  *		used
  * @score: optional score atomic shared with other schedulers
  * @name: name used for debugging
+ * @sched_policy: schedule policy
  * @dev: target &struct device
  *
  * Return 0 on success, otherwise error code.
@@ -1081,9 +1082,15 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
 		   struct workqueue_struct *submit_wq,
 		   unsigned hw_submission, unsigned hang_limit,
 		   long timeout, struct workqueue_struct *timeout_wq,
-		   atomic_t *score, const char *name, struct device *dev)
+		   atomic_t *score, const char *name,
+		   enum drm_sched_policy sched_policy,
+		   struct device *dev)
 {
 	int i;
+
+	if (sched_policy >= DRM_SCHED_POLICY_COUNT)
+		return -EINVAL;
+
 	sched->ops = ops;
 	sched->hw_submission_limit = hw_submission;
 	sched->name = name;
@@ -1102,6 +1109,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
 	sched->hang_limit = hang_limit;
 	sched->score = score ? score : &sched->_score;
 	sched->dev = dev;
+	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
+		drm_sched_policy_default : sched_policy;
 	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
 		drm_sched_rq_init(sched, &sched->sched_rq[i]);
 
diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
index 38e092ea41e6..dec89c5b8cb1 100644
--- a/drivers/gpu/drm/v3d/v3d_sched.c
+++ b/drivers/gpu/drm/v3d/v3d_sched.c
@@ -391,7 +391,8 @@ v3d_sched_init(struct v3d_dev *v3d)
 			     &v3d_bin_sched_ops, NULL,
 			     hw_jobs_limit, job_hang_limit,
 			     msecs_to_jiffies(hang_limit_ms), NULL,
-			     NULL, "v3d_bin", v3d->drm.dev);
+			     NULL, "v3d_bin", DRM_SCHED_POLICY_UNSET,
+			     v3d->drm.dev);
 	if (ret)
 		return ret;
 
@@ -399,7 +400,8 @@ v3d_sched_init(struct v3d_dev *v3d)
 			     &v3d_render_sched_ops, NULL,
 			     hw_jobs_limit, job_hang_limit,
 			     msecs_to_jiffies(hang_limit_ms), NULL,
-			     NULL, "v3d_render", v3d->drm.dev);
+			     NULL, "v3d_render", DRM_SCHED_POLICY_UNSET,
+			     v3d->drm.dev);
 	if (ret)
 		goto fail;
 
@@ -407,7 +409,8 @@ v3d_sched_init(struct v3d_dev *v3d)
 			     &v3d_tfu_sched_ops, NULL,
 			     hw_jobs_limit, job_hang_limit,
 			     msecs_to_jiffies(hang_limit_ms), NULL,
-			     NULL, "v3d_tfu", v3d->drm.dev);
+			     NULL, "v3d_tfu", DRM_SCHED_POLICY_UNSET,
+			     v3d->drm.dev);
 	if (ret)
 		goto fail;
 
@@ -416,7 +419,8 @@ v3d_sched_init(struct v3d_dev *v3d)
 				     &v3d_csd_sched_ops, NULL,
 				     hw_jobs_limit, job_hang_limit,
 				     msecs_to_jiffies(hang_limit_ms), NULL,
-				     NULL, "v3d_csd", v3d->drm.dev);
+				     NULL, "v3d_csd", DRM_SCHED_POLICY_UNSET,
+				     v3d->drm.dev);
 		if (ret)
 			goto fail;
 
@@ -424,7 +428,8 @@ v3d_sched_init(struct v3d_dev *v3d)
 				     &v3d_cache_clean_sched_ops, NULL,
 				     hw_jobs_limit, job_hang_limit,
 				     msecs_to_jiffies(hang_limit_ms), NULL,
-				     NULL, "v3d_cache_clean", v3d->drm.dev);
+				     NULL, "v3d_cache_clean",
+				     DRM_SCHED_POLICY_UNSET, v3d->drm.dev);
 		if (ret)
 			goto fail;
 	}
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 211bd3cdabdc..320f0a720486 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -72,11 +72,15 @@ enum drm_sched_priority {
 	DRM_SCHED_PRIORITY_UNSET = -2
 };
 
-/* Used to chose between FIFO and RR jobs scheduling */
-extern int drm_sched_policy;
-
-#define DRM_SCHED_POLICY_RR    0
-#define DRM_SCHED_POLICY_FIFO  1
+/* Used to chose default scheduling policy*/
+extern int default_drm_sched_policy;
+
+enum drm_sched_policy {
+	DRM_SCHED_POLICY_UNSET,
+	DRM_SCHED_POLICY_RR,
+	DRM_SCHED_POLICY_FIFO,
+	DRM_SCHED_POLICY_COUNT,
+};
 
 /**
  * struct drm_sched_entity - A wrapper around a job queue (typically
@@ -489,6 +493,7 @@ struct drm_sched_backend_ops {
  *              guilty and it will no longer be considered for scheduling.
  * @score: score to help loadbalancer pick a idle sched
  * @_score: score used when the driver doesn't provide one
+ * @sched_policy: Schedule policy for scheduler
  * @ready: marks if the underlying HW is ready to work
  * @free_guilty: A hit to time out handler to free the guilty job.
  * @pause_submit: pause queuing of @work_submit on @submit_wq
@@ -515,6 +520,7 @@ struct drm_gpu_scheduler {
 	int				hang_limit;
 	atomic_t                        *score;
 	atomic_t                        _score;
+	enum drm_sched_policy		sched_policy;
 	bool				ready;
 	bool				free_guilty;
 	bool				pause_submit;
@@ -527,7 +533,9 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
 		   struct workqueue_struct *submit_wq,
 		   uint32_t hw_submission, unsigned hang_limit,
 		   long timeout, struct workqueue_struct *timeout_wq,
-		   atomic_t *score, const char *name, struct device *dev);
+		   atomic_t *score, const char *name,
+		   enum drm_sched_policy sched_policy,
+		   struct device *dev);
 
 void drm_sched_fini(struct drm_gpu_scheduler *sched);
 int drm_sched_job_init(struct drm_sched_job *job,
-- 
2.34.1

[PATCH v5 4/7] drm/sched: Add DRM_SCHED_POLICY_SINGLE_ENTITY scheduling policy

[Matthew Brost]

DRM_SCHED_POLICY_SINGLE_ENTITY creates a 1 to 1 relationship between
scheduler and entity. No priorities or run queue used in this mode.
Intended for devices with firmware schedulers.

v2:
  - Drop sched / rq union (Luben)
v3:
  - Don't pick entity if stopped in drm_sched_select_entity (Danilo)
v4:
  - Rework if statement in drm_sched_entity_init (Luben)
  - Update comment for drm_sched_entity_to_scheduler (Luben)
  - Reword a few things in DOC comment (Luben)
  - Do not check sched policy in for statement (Luben)

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 drivers/gpu/drm/scheduler/sched_entity.c | 70 ++++++++++++++-----
 drivers/gpu/drm/scheduler/sched_fence.c  |  2 +-
 drivers/gpu/drm/scheduler/sched_main.c   | 86 ++++++++++++++++++------
 include/drm/gpu_scheduler.h              |  8 +++
 4 files changed, 131 insertions(+), 35 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index cf42e2265d64..1ef3883764f9 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -83,6 +83,7 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
 	memset(entity, 0, sizeof(struct drm_sched_entity));
 	INIT_LIST_HEAD(&entity->list);
 	entity->rq = NULL;
+	entity->single_sched = NULL;
 	entity->guilty = guilty;
 	entity->num_sched_list = num_sched_list;
 	entity->priority = priority;
@@ -90,8 +91,18 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
 	RCU_INIT_POINTER(entity->last_scheduled, NULL);
 	RB_CLEAR_NODE(&entity->rb_tree_node);
 
-	if(num_sched_list)
-		entity->rq = &sched_list[0]->sched_rq[entity->priority];
+
+	if (num_sched_list) {
+		if (sched_list[0]->sched_policy !=
+		    DRM_SCHED_POLICY_SINGLE_ENTITY) {
+			entity->rq = &sched_list[0]->sched_rq[entity->priority];
+		} else if (num_sched_list == 1 && !sched_list[0]->single_entity) {
+			sched_list[0]->single_entity = entity;
+			entity->single_sched = sched_list[0];
+		} else {
+			return -EINVAL;
+		}
+	}
 
 	init_completion(&entity->entity_idle);
 
@@ -124,7 +135,8 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
 				    struct drm_gpu_scheduler **sched_list,
 				    unsigned int num_sched_list)
 {
-	WARN_ON(!num_sched_list || !sched_list);
+	WARN_ON(!num_sched_list || !sched_list ||
+		!!entity->single_sched);
 
 	entity->sched_list = sched_list;
 	entity->num_sched_list = num_sched_list;
@@ -231,13 +243,15 @@ static void drm_sched_entity_kill(struct drm_sched_entity *entity)
 {
 	struct drm_sched_job *job;
 	struct dma_fence *prev;
+	bool single_entity = !!entity->single_sched;
 
-	if (!entity->rq)
+	if (!entity->rq && !single_entity)
 		return;
 
 	spin_lock(&entity->rq_lock);
 	entity->stopped = true;
-	drm_sched_rq_remove_entity(entity->rq, entity);
+	if (!single_entity)
+		drm_sched_rq_remove_entity(entity->rq, entity);
 	spin_unlock(&entity->rq_lock);
 
 	/* Make sure this entity is not used by the scheduler at the moment */
@@ -259,6 +273,20 @@ static void drm_sched_entity_kill(struct drm_sched_entity *entity)
 	dma_fence_put(prev);
 }
 
+/**
+ * drm_sched_entity_to_scheduler - Schedule entity to GPU scheduler
+ * @entity: scheduler entity
+ *
+ * Returns GPU scheduler for the entity
+ */
+struct drm_gpu_scheduler *
+drm_sched_entity_to_scheduler(struct drm_sched_entity *entity)
+{
+	bool single_entity = !!entity->single_sched;
+
+	return single_entity ? entity->single_sched : entity->rq->sched;
+}
+
 /**
  * drm_sched_entity_flush - Flush a context entity
  *
@@ -276,11 +304,12 @@ long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout)
 	struct drm_gpu_scheduler *sched;
 	struct task_struct *last_user;
 	long ret = timeout;
+	bool single_entity = !!entity->single_sched;
 
-	if (!entity->rq)
+	if (!entity->rq && !single_entity)
 		return 0;
 
-	sched = entity->rq->sched;
+	sched = drm_sched_entity_to_scheduler(entity);
 	/**
 	 * The client will not queue more IBs during this fini, consume existing
 	 * queued IBs or discard them on SIGKILL
@@ -373,7 +402,7 @@ static void drm_sched_entity_wakeup(struct dma_fence *f,
 		container_of(cb, struct drm_sched_entity, cb);
 
 	drm_sched_entity_clear_dep(f, cb);
-	drm_sched_wakeup_if_can_queue(entity->rq->sched);
+	drm_sched_wakeup_if_can_queue(drm_sched_entity_to_scheduler(entity));
 }
 
 /**
@@ -387,6 +416,8 @@ static void drm_sched_entity_wakeup(struct dma_fence *f,
 void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
 				   enum drm_sched_priority priority)
 {
+	WARN_ON(!!entity->single_sched);
+
 	spin_lock(&entity->rq_lock);
 	entity->priority = priority;
 	spin_unlock(&entity->rq_lock);
@@ -399,7 +430,7 @@ EXPORT_SYMBOL(drm_sched_entity_set_priority);
  */
 static bool drm_sched_entity_add_dependency_cb(struct drm_sched_entity *entity)
 {
-	struct drm_gpu_scheduler *sched = entity->rq->sched;
+	struct drm_gpu_scheduler *sched = drm_sched_entity_to_scheduler(entity);
 	struct dma_fence *fence = entity->dependency;
 	struct drm_sched_fence *s_fence;
 
@@ -501,7 +532,8 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
 	 * Update the entity's location in the min heap according to
 	 * the timestamp of the next job, if any.
 	 */
-	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
+	if (drm_sched_entity_to_scheduler(entity)->sched_policy ==
+	    DRM_SCHED_POLICY_FIFO) {
 		struct drm_sched_job *next;
 
 		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
@@ -524,6 +556,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
 	struct drm_gpu_scheduler *sched;
 	struct drm_sched_rq *rq;
 
+	WARN_ON(!!entity->single_sched);
+
 	/* single possible engine and already selected */
 	if (!entity->sched_list)
 		return;
@@ -573,12 +607,13 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
 void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
 {
 	struct drm_sched_entity *entity = sched_job->entity;
-	bool first, fifo = entity->rq->sched->sched_policy ==
-		DRM_SCHED_POLICY_FIFO;
+	bool single_entity = !!entity->single_sched;
+	bool first;
 	ktime_t submit_ts;
 
 	trace_drm_sched_job(sched_job, entity);
-	atomic_inc(entity->rq->sched->score);
+	if (!single_entity)
+		atomic_inc(entity->rq->sched->score);
 	WRITE_ONCE(entity->last_user, current->group_leader);
 
 	/*
@@ -591,6 +626,10 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
 
 	/* first job wakes up scheduler */
 	if (first) {
+		struct drm_gpu_scheduler *sched =
+			drm_sched_entity_to_scheduler(entity);
+		bool fifo = sched->sched_policy == DRM_SCHED_POLICY_FIFO;
+
 		/* Add the entity to the run queue */
 		spin_lock(&entity->rq_lock);
 		if (entity->stopped) {
@@ -600,13 +639,14 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
 			return;
 		}
 
-		drm_sched_rq_add_entity(entity->rq, entity);
+		if (!single_entity)
+			drm_sched_rq_add_entity(entity->rq, entity);
 		spin_unlock(&entity->rq_lock);
 
 		if (fifo)
 			drm_sched_rq_update_fifo(entity, submit_ts);
 
-		drm_sched_wakeup_if_can_queue(entity->rq->sched);
+		drm_sched_wakeup_if_can_queue(sched);
 	}
 }
 EXPORT_SYMBOL(drm_sched_entity_push_job);
diff --git a/drivers/gpu/drm/scheduler/sched_fence.c b/drivers/gpu/drm/scheduler/sched_fence.c
index 06cedfe4b486..f6b926f5e188 100644
--- a/drivers/gpu/drm/scheduler/sched_fence.c
+++ b/drivers/gpu/drm/scheduler/sched_fence.c
@@ -225,7 +225,7 @@ void drm_sched_fence_init(struct drm_sched_fence *fence,
 {
 	unsigned seq;
 
-	fence->sched = entity->rq->sched;
+	fence->sched = drm_sched_entity_to_scheduler(entity);
 	seq = atomic_inc_return(&entity->fence_seq);
 	dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled,
 		       &fence->lock, entity->fence_context, seq);
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 150e5330f0fa..7dbb3392124d 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -32,7 +32,8 @@
  * backend operations to the scheduler like submitting a job to hardware run queue,
  * returning the dependencies of a job etc.
  *
- * The organisation of the scheduler is the following:
+ * For scheduling policies DRM_SCHED_POLICY_RR and DRM_SCHED_POLICY_FIFO, the
+ * scheduler organization is:
  *
  * 1. Each hw run queue has one scheduler
  * 2. Each scheduler has multiple run queues with different priorities
@@ -43,7 +44,24 @@
  *
  * The jobs in a entity are always scheduled in the order that they were pushed.
  *
- * Note that once a job was taken from the entities queue and pushed to the
+ * For DRM_SCHED_POLICY_SINGLE_ENTITY, the organization of the scheduler is:
+ *
+ * 1. One to one relationship between scheduler and entity
+ * 2. No priorities implemented per scheduler (single job queue)
+ * 3. No run queues in scheduler rather jobs are directly dequeued from entity
+ * 4. The entity maintains a queue of jobs that will be scheduled to the
+ * hardware
+ *
+ * The jobs in a entity are always scheduled in the order that they were pushed
+ * regardless of scheduling policy. Single-entity scheduling is essentially a
+ * FIFO for jobs.
+ *
+ * A policy of DRM_SCHED_POLICY_RR or DRM_SCHED_POLICY_FIFO is expected to be
+ * used when the kernel-mode driver is scheduling directly to the hardware while
+ * a scheduling policy of DRM_SCHED_POLICY_SINGLE_ENTITY is expected to be used
+ * when there is a firmware scheduler.
+ *
+ * Note that once a job is taken from the entities queue and pushed to the
  * hardware, i.e. the pending queue, the entity must not be referenced anymore
  * through the jobs entity pointer.
  */
@@ -96,6 +114,8 @@ static inline void drm_sched_rq_remove_fifo_locked(struct drm_sched_entity *enti
 
 void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
 {
+	WARN_ON(!!entity->single_sched);
+
 	/*
 	 * Both locks need to be grabbed, one to protect from entity->rq change
 	 * for entity from within concurrent drm_sched_entity_select_rq and the
@@ -126,6 +146,8 @@ void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
 static void drm_sched_rq_init(struct drm_gpu_scheduler *sched,
 			      struct drm_sched_rq *rq)
 {
+	WARN_ON(sched->sched_policy == DRM_SCHED_POLICY_SINGLE_ENTITY);
+
 	spin_lock_init(&rq->lock);
 	INIT_LIST_HEAD(&rq->entities);
 	rq->rb_tree_root = RB_ROOT_CACHED;
@@ -144,6 +166,8 @@ static void drm_sched_rq_init(struct drm_gpu_scheduler *sched,
 void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
 			     struct drm_sched_entity *entity)
 {
+	WARN_ON(!!entity->single_sched);
+
 	if (!list_empty(&entity->list))
 		return;
 
@@ -166,6 +190,8 @@ void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
 void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
 				struct drm_sched_entity *entity)
 {
+	WARN_ON(!!entity->single_sched);
+
 	if (list_empty(&entity->list))
 		return;
 
@@ -641,7 +667,7 @@ int drm_sched_job_init(struct drm_sched_job *job,
 		       struct drm_sched_entity *entity,
 		       void *owner)
 {
-	if (!entity->rq)
+	if (!entity->rq && !entity->single_sched)
 		return -ENOENT;
 
 	job->entity = entity;
@@ -674,13 +700,16 @@ void drm_sched_job_arm(struct drm_sched_job *job)
 {
 	struct drm_gpu_scheduler *sched;
 	struct drm_sched_entity *entity = job->entity;
+	bool single_entity = !!entity->single_sched;
 
 	BUG_ON(!entity);
-	drm_sched_entity_select_rq(entity);
-	sched = entity->rq->sched;
+	if (!single_entity)
+		drm_sched_entity_select_rq(entity);
+	sched = drm_sched_entity_to_scheduler(entity);
 
 	job->sched = sched;
-	job->s_priority = entity->rq - sched->sched_rq;
+	if (!single_entity)
+		job->s_priority = entity->rq - sched->sched_rq;
 	job->id = atomic64_inc_return(&sched->job_id_count);
 
 	drm_sched_fence_init(job->s_fence, job->entity);
@@ -896,6 +925,14 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
 	if (!drm_sched_can_queue(sched))
 		return NULL;
 
+	if (sched->single_entity) {
+		if (!READ_ONCE(sched->single_entity->stopped) &&
+		    drm_sched_entity_is_ready(sched->single_entity))
+			return sched->single_entity;
+
+		return NULL;
+	}
+
 	/* Kernel run queue has higher priority than normal run queue*/
 	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
 		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
@@ -1092,6 +1129,7 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
 		return -EINVAL;
 
 	sched->ops = ops;
+	sched->single_entity = NULL;
 	sched->hw_submission_limit = hw_submission;
 	sched->name = name;
 	if (submit_wq) {
@@ -1111,8 +1149,10 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
 	sched->dev = dev;
 	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
 		drm_sched_policy_default : sched_policy;
-	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
-		drm_sched_rq_init(sched, &sched->sched_rq[i]);
+	if (sched_policy != DRM_SCHED_POLICY_SINGLE_ENTITY) {
+		for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
+			drm_sched_rq_init(sched, &sched->sched_rq[i]);
+	}
 
 	init_waitqueue_head(&sched->job_scheduled);
 	INIT_LIST_HEAD(&sched->pending_list);
@@ -1143,19 +1183,25 @@ void drm_sched_fini(struct drm_gpu_scheduler *sched)
 
 	drm_sched_wqueue_stop(sched);
 
-	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
-		struct drm_sched_rq *rq = &sched->sched_rq[i];
+	if (sched->single_entity) {
+		spin_lock(&sched->single_entity->rq_lock);
+		sched->single_entity->stopped = true;
+		spin_unlock(&sched->single_entity->rq_lock);
+	} else if (sched->sched_policy != DRM_SCHED_POLICY_SINGLE_ENTITY) {
+		for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
+			struct drm_sched_rq *rq = &sched->sched_rq[i];
 
-		spin_lock(&rq->lock);
-		list_for_each_entry(s_entity, &rq->entities, list)
-			/*
-			 * Prevents reinsertion and marks job_queue as idle,
-			 * it will removed from rq in drm_sched_entity_fini
-			 * eventually
-			 */
-			s_entity->stopped = true;
-		spin_unlock(&rq->lock);
+			spin_lock(&rq->lock);
+			list_for_each_entry(s_entity, &rq->entities, list)
+				/*
+				 * Prevents reinsertion and marks job_queue as idle,
+				 * it will removed from rq in drm_sched_entity_fini
+				 * eventually
+				 */
+				s_entity->stopped = true;
+			spin_unlock(&rq->lock);
 
+		}
 	}
 
 	/* Wakeup everyone stuck in drm_sched_entity_flush for this scheduler */
@@ -1186,6 +1232,8 @@ void drm_sched_increase_karma(struct drm_sched_job *bad)
 	struct drm_sched_entity *entity;
 	struct drm_gpu_scheduler *sched = bad->sched;
 
+	WARN_ON(sched->sched_policy == DRM_SCHED_POLICY_SINGLE_ENTITY);
+
 	/* don't change @bad's karma if it's from KERNEL RQ,
 	 * because sometimes GPU hang would cause kernel jobs (like VM updating jobs)
 	 * corrupt but keep in mind that kernel jobs always considered good.
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 320f0a720486..e67b53c3546b 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -79,6 +79,7 @@ enum drm_sched_policy {
 	DRM_SCHED_POLICY_UNSET,
 	DRM_SCHED_POLICY_RR,
 	DRM_SCHED_POLICY_FIFO,
+	DRM_SCHED_POLICY_SINGLE_ENTITY,
 	DRM_SCHED_POLICY_COUNT,
 };
 
@@ -112,6 +113,9 @@ struct drm_sched_entity {
 	 */
 	struct drm_sched_rq		*rq;
 
+	/** @single_sched: Single scheduler */
+	struct drm_gpu_scheduler	*single_sched;
+
 	/**
 	 * @sched_list:
 	 *
@@ -473,6 +477,7 @@ struct drm_sched_backend_ops {
  * struct drm_gpu_scheduler - scheduler instance-specific data
  *
  * @ops: backend operations provided by the driver.
+ * @single_entity: Single entity for the scheduler
  * @hw_submission_limit: the max size of the hardware queue.
  * @timeout: the time after which a job is removed from the scheduler.
  * @name: name of the ring for which this scheduler is being used.
@@ -504,6 +509,7 @@ struct drm_sched_backend_ops {
  */
 struct drm_gpu_scheduler {
 	const struct drm_sched_backend_ops	*ops;
+	struct drm_sched_entity		*single_entity;
 	uint32_t			hw_submission_limit;
 	long				timeout;
 	const char			*name;
@@ -587,6 +593,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
 			  struct drm_gpu_scheduler **sched_list,
 			  unsigned int num_sched_list,
 			  atomic_t *guilty);
+struct drm_gpu_scheduler *
+drm_sched_entity_to_scheduler(struct drm_sched_entity *entity);
 long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout);
 void drm_sched_entity_fini(struct drm_sched_entity *entity);
 void drm_sched_entity_destroy(struct drm_sched_entity *entity);
-- 
2.34.1

[PATCH v5 5/7] drm/sched: Split free_job into own work item

[Matthew Brost]

Rather than call free_job and run_job in same work item have a dedicated
work item for each. This aligns with the design and intended use of work
queues.

v2:
   - Test for DMA_FENCE_FLAG_TIMESTAMP_BIT before setting
     timestamp in free_job() work item (Danilo)
v3:
  - Drop forward dec of drm_sched_select_entity (Boris)
  - Return in drm_sched_run_job_work if entity NULL (Boris)
v4:
  - Replace dequeue with peek and invert logic (Luben)
  - Wrap to 100 lines (Luben)
  - Update comments for *_queue / *_queue_if_ready functions (Luben)

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 drivers/gpu/drm/scheduler/sched_main.c | 287 +++++++++++++++----------
 include/drm/gpu_scheduler.h            |   8 +-
 2 files changed, 178 insertions(+), 117 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 7dbb3392124d..cf4c23db7547 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -213,11 +213,12 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
  * drm_sched_rq_select_entity_rr - Select an entity which could provide a job to run
  *
  * @rq: scheduler run queue to check.
+ * @peek: Just find, don't set to current.
  *
  * Try to find a ready entity, returns NULL if none found.
  */
 static struct drm_sched_entity *
-drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq)
+drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq, bool peek)
 {
 	struct drm_sched_entity *entity;
 
@@ -227,8 +228,10 @@ drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq)
 	if (entity) {
 		list_for_each_entry_continue(entity, &rq->entities, list) {
 			if (drm_sched_entity_is_ready(entity)) {
-				rq->current_entity = entity;
-				reinit_completion(&entity->entity_idle);
+				if (!peek) {
+					rq->current_entity = entity;
+					reinit_completion(&entity->entity_idle);
+				}
 				spin_unlock(&rq->lock);
 				return entity;
 			}
@@ -238,8 +241,10 @@ drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq)
 	list_for_each_entry(entity, &rq->entities, list) {
 
 		if (drm_sched_entity_is_ready(entity)) {
-			rq->current_entity = entity;
-			reinit_completion(&entity->entity_idle);
+			if (!peek) {
+				rq->current_entity = entity;
+				reinit_completion(&entity->entity_idle);
+			}
 			spin_unlock(&rq->lock);
 			return entity;
 		}
@@ -257,11 +262,12 @@ drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq)
  * drm_sched_rq_select_entity_fifo - Select an entity which provides a job to run
  *
  * @rq: scheduler run queue to check.
+ * @peek: Just find, don't set to current.
  *
  * Find oldest waiting ready entity, returns NULL if none found.
  */
 static struct drm_sched_entity *
-drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
+drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq, bool peek)
 {
 	struct rb_node *rb;
 
@@ -271,8 +277,10 @@ drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
 
 		entity = rb_entry(rb, struct drm_sched_entity, rb_tree_node);
 		if (drm_sched_entity_is_ready(entity)) {
-			rq->current_entity = entity;
-			reinit_completion(&entity->entity_idle);
+			if (!peek) {
+				rq->current_entity = entity;
+				reinit_completion(&entity->entity_idle);
+			}
 			break;
 		}
 	}
@@ -282,13 +290,98 @@ drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
 }
 
 /**
- * drm_sched_wqueue_enqueue - enqueue scheduler submission
+ * drm_sched_run_job_queue - enqueue run-job work
+ * @sched: scheduler instance
+ */
+static void drm_sched_run_job_queue(struct drm_gpu_scheduler *sched)
+{
+	if (!READ_ONCE(sched->pause_submit))
+		queue_work(sched->submit_wq, &sched->work_run_job);
+}
+
+/**
+ * drm_sched_can_queue -- Can we queue more to the hardware?
+ * @sched: scheduler instance
+ *
+ * Return true if we can push more jobs to the hw, otherwise false.
+ */
+static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
+{
+	return atomic_read(&sched->hw_rq_count) <
+		sched->hw_submission_limit;
+}
+
+/**
+ * drm_sched_select_entity - Select next entity to process
+ *
+ * @sched: scheduler instance
+ * @peek: Just find, don't set to current.
+ *
+ * Returns the entity to process or NULL if none are found.
+ */
+static struct drm_sched_entity *
+drm_sched_select_entity(struct drm_gpu_scheduler *sched, bool peek)
+{
+	struct drm_sched_entity *entity;
+	int i;
+
+	if (!drm_sched_can_queue(sched))
+		return NULL;
+
+	if (sched->single_entity) {
+		if (!READ_ONCE(sched->single_entity->stopped) &&
+		    drm_sched_entity_is_ready(sched->single_entity))
+			return sched->single_entity;
+
+		return NULL;
+	}
+
+	/* Kernel run queue has higher priority than normal run queue*/
+	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
+		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
+			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i], peek) :
+			drm_sched_rq_select_entity_rr(&sched->sched_rq[i], peek);
+		if (entity)
+			break;
+	}
+
+	return entity;
+}
+
+/**
+ * drm_sched_run_job_queue_if_ready - enqueue run-job work if ready
+ * @sched: scheduler instance
+ */
+static void drm_sched_run_job_queue_if_ready(struct drm_gpu_scheduler *sched)
+{
+	if (drm_sched_select_entity(sched, false))
+		drm_sched_run_job_queue(sched);
+}
+
+/**
+ * drm_sched_free_job_queue - enqueue free-job work
  * @sched: scheduler instance
  */
-static void drm_sched_wqueue_enqueue(struct drm_gpu_scheduler *sched)
+static void drm_sched_free_job_queue(struct drm_gpu_scheduler *sched)
 {
 	if (!READ_ONCE(sched->pause_submit))
-		queue_work(sched->submit_wq, &sched->work_submit);
+		queue_work(sched->submit_wq, &sched->work_free_job);
+}
+
+/**
+ * drm_sched_free_job_queue_if_ready - enqueue free-job work if ready
+ * @sched: scheduler instance
+ */
+static void drm_sched_free_job_queue_if_ready(struct drm_gpu_scheduler *sched)
+{
+	struct drm_sched_job *job;
+
+	spin_lock(&sched->job_list_lock);
+	job = list_first_entry_or_null(&sched->pending_list,
+				       struct drm_sched_job, list);
+	if (job && dma_fence_is_signaled(&job->s_fence->finished))
+		drm_sched_free_job_queue(sched);
+	spin_unlock(&sched->job_list_lock);
 }
 
 /**
@@ -310,7 +403,7 @@ static void drm_sched_job_done(struct drm_sched_job *s_job, int result)
 	dma_fence_get(&s_fence->finished);
 	drm_sched_fence_finished(s_fence, result);
 	dma_fence_put(&s_fence->finished);
-	drm_sched_wqueue_enqueue(sched);
+	drm_sched_free_job_queue(sched);
 }
 
 /**
@@ -576,7 +669,7 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
 				drm_sched_job_done(s_job, fence->error);
 			else if (r)
 				DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n",
-					  r);
+					      r);
 		} else
 			drm_sched_job_done(s_job, -ECANCELED);
 	}
@@ -885,18 +978,6 @@ void drm_sched_job_cleanup(struct drm_sched_job *job)
 }
 EXPORT_SYMBOL(drm_sched_job_cleanup);
 
-/**
- * drm_sched_can_queue -- Can we queue more to the hardware?
- * @sched: scheduler instance
- *
- * Return true if we can push more jobs to the hw, otherwise false.
- */
-static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
-{
-	return atomic_read(&sched->hw_rq_count) <
-		sched->hw_submission_limit;
-}
-
 /**
  * drm_sched_wakeup_if_can_queue - Wake up the scheduler
  * @sched: scheduler instance
@@ -906,43 +987,7 @@ static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
 void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched)
 {
 	if (drm_sched_can_queue(sched))
-		drm_sched_wqueue_enqueue(sched);
-}
-
-/**
- * drm_sched_select_entity - Select next entity to process
- *
- * @sched: scheduler instance
- *
- * Returns the entity to process or NULL if none are found.
- */
-static struct drm_sched_entity *
-drm_sched_select_entity(struct drm_gpu_scheduler *sched)
-{
-	struct drm_sched_entity *entity;
-	int i;
-
-	if (!drm_sched_can_queue(sched))
-		return NULL;
-
-	if (sched->single_entity) {
-		if (!READ_ONCE(sched->single_entity->stopped) &&
-		    drm_sched_entity_is_ready(sched->single_entity))
-			return sched->single_entity;
-
-		return NULL;
-	}
-
-	/* Kernel run queue has higher priority than normal run queue*/
-	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
-		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
-			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i]) :
-			drm_sched_rq_select_entity_rr(&sched->sched_rq[i]);
-		if (entity)
-			break;
-	}
-
-	return entity;
+		drm_sched_run_job_queue(sched);
 }
 
 /**
@@ -974,8 +1019,10 @@ drm_sched_get_cleanup_job(struct drm_gpu_scheduler *sched)
 						typeof(*next), list);
 
 		if (next) {
-			next->s_fence->scheduled.timestamp =
-				dma_fence_timestamp(&job->s_fence->finished);
+			if (test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT,
+				     &next->s_fence->scheduled.flags))
+				next->s_fence->scheduled.timestamp =
+					dma_fence_timestamp(&job->s_fence->finished);
 			/* start TO timer for next job */
 			drm_sched_start_timeout(sched);
 		}
@@ -1025,74 +1072,83 @@ drm_sched_pick_best(struct drm_gpu_scheduler **sched_list,
 EXPORT_SYMBOL(drm_sched_pick_best);
 
 /**
- * drm_sched_main - main scheduler thread
+ * drm_sched_free_job_work - worker to call free_job
  *
- * @param: scheduler instance
+ * @w: free job work
  */
-static void drm_sched_main(struct work_struct *w)
+static void drm_sched_free_job_work(struct work_struct *w)
 {
 	struct drm_gpu_scheduler *sched =
-		container_of(w, struct drm_gpu_scheduler, work_submit);
-	struct drm_sched_entity *entity;
+		container_of(w, struct drm_gpu_scheduler, work_free_job);
 	struct drm_sched_job *cleanup_job;
-	int r;
 
 	if (READ_ONCE(sched->pause_submit))
 		return;
 
 	cleanup_job = drm_sched_get_cleanup_job(sched);
-	entity = drm_sched_select_entity(sched);
-
-	if (!entity && !cleanup_job)
-		return;	/* No more work */
-
-	if (cleanup_job)
+	if (cleanup_job) {
 		sched->ops->free_job(cleanup_job);
 
-	if (entity) {
-		struct dma_fence *fence;
-		struct drm_sched_fence *s_fence;
-		struct drm_sched_job *sched_job;
-
-		sched_job = drm_sched_entity_pop_job(entity);
-		if (!sched_job) {
-			complete_all(&entity->entity_idle);
-			if (!cleanup_job)
-				return;	/* No more work */
-			goto again;
-		}
+		drm_sched_free_job_queue_if_ready(sched);
+		drm_sched_run_job_queue_if_ready(sched);
+	}
+}
 
-		s_fence = sched_job->s_fence;
+/**
+ * drm_sched_run_job_work - worker to call run_job
+ *
+ * @w: run job work
+ */
+static void drm_sched_run_job_work(struct work_struct *w)
+{
+	struct drm_gpu_scheduler *sched =
+		container_of(w, struct drm_gpu_scheduler, work_run_job);
+	struct drm_sched_entity *entity;
+	struct dma_fence *fence;
+	struct drm_sched_fence *s_fence;
+	struct drm_sched_job *sched_job;
+	int r;
 
-		atomic_inc(&sched->hw_rq_count);
-		drm_sched_job_begin(sched_job);
+	if (READ_ONCE(sched->pause_submit))
+		return;
+
+	entity = drm_sched_select_entity(sched, true);
+	if (!entity)
+		return;
 
-		trace_drm_run_job(sched_job, entity);
-		fence = sched->ops->run_job(sched_job);
+	sched_job = drm_sched_entity_pop_job(entity);
+	if (!sched_job) {
 		complete_all(&entity->entity_idle);
-		drm_sched_fence_scheduled(s_fence, fence);
+		return;	/* No more work */
+	}
 
-		if (!IS_ERR_OR_NULL(fence)) {
-			/* Drop for original kref_init of the fence */
-			dma_fence_put(fence);
+	s_fence = sched_job->s_fence;
 
-			r = dma_fence_add_callback(fence, &sched_job->cb,
-						   drm_sched_job_done_cb);
-			if (r == -ENOENT)
-				drm_sched_job_done(sched_job, fence->error);
-			else if (r)
-				DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n",
-					  r);
-		} else {
-			drm_sched_job_done(sched_job, IS_ERR(fence) ?
-					   PTR_ERR(fence) : 0);
-		}
+	atomic_inc(&sched->hw_rq_count);
+	drm_sched_job_begin(sched_job);
 
-		wake_up(&sched->job_scheduled);
+	trace_drm_run_job(sched_job, entity);
+	fence = sched->ops->run_job(sched_job);
+	complete_all(&entity->entity_idle);
+	drm_sched_fence_scheduled(s_fence, fence);
+
+	if (!IS_ERR_OR_NULL(fence)) {
+		/* Drop for original kref_init of the fence */
+		dma_fence_put(fence);
+
+		r = dma_fence_add_callback(fence, &sched_job->cb,
+					   drm_sched_job_done_cb);
+		if (r == -ENOENT)
+			drm_sched_job_done(sched_job, fence->error);
+		else if (r)
+			DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n", r);
+	} else {
+		drm_sched_job_done(sched_job, IS_ERR(fence) ?
+				   PTR_ERR(fence) : 0);
 	}
 
-again:
-	drm_sched_wqueue_enqueue(sched);
+	wake_up(&sched->job_scheduled);
+	drm_sched_run_job_queue_if_ready(sched);
 }
 
 /**
@@ -1159,7 +1215,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
 	spin_lock_init(&sched->job_list_lock);
 	atomic_set(&sched->hw_rq_count, 0);
 	INIT_DELAYED_WORK(&sched->work_tdr, drm_sched_job_timedout);
-	INIT_WORK(&sched->work_submit, drm_sched_main);
+	INIT_WORK(&sched->work_run_job, drm_sched_run_job_work);
+	INIT_WORK(&sched->work_free_job, drm_sched_free_job_work);
 	atomic_set(&sched->_score, 0);
 	atomic64_set(&sched->job_id_count, 0);
 	sched->pause_submit = false;
@@ -1283,7 +1340,8 @@ EXPORT_SYMBOL(drm_sched_wqueue_ready);
 void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched)
 {
 	WRITE_ONCE(sched->pause_submit, true);
-	cancel_work_sync(&sched->work_submit);
+	cancel_work_sync(&sched->work_run_job);
+	cancel_work_sync(&sched->work_free_job);
 }
 EXPORT_SYMBOL(drm_sched_wqueue_stop);
 
@@ -1295,6 +1353,7 @@ EXPORT_SYMBOL(drm_sched_wqueue_stop);
 void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched)
 {
 	WRITE_ONCE(sched->pause_submit, false);
-	queue_work(sched->submit_wq, &sched->work_submit);
+	queue_work(sched->submit_wq, &sched->work_run_job);
+	queue_work(sched->submit_wq, &sched->work_free_job);
 }
 EXPORT_SYMBOL(drm_sched_wqueue_start);
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index e67b53c3546b..625ffe040de3 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -487,9 +487,10 @@ struct drm_sched_backend_ops {
  *                 finished.
  * @hw_rq_count: the number of jobs currently in the hardware queue.
  * @job_id_count: used to assign unique id to the each job.
- * @submit_wq: workqueue used to queue @work_submit
+ * @submit_wq: workqueue used to queue @work_run_job and @work_free_job
  * @timeout_wq: workqueue used to queue @work_tdr
- * @work_submit: schedules jobs and cleans up entities
+ * @work_run_job: schedules jobs
+ * @work_free_job: cleans up jobs
  * @work_tdr: schedules a delayed call to @drm_sched_job_timedout after the
  *            timeout interval is over.
  * @pending_list: the list of jobs which are currently in the job queue.
@@ -519,7 +520,8 @@ struct drm_gpu_scheduler {
 	atomic64_t			job_id_count;
 	struct workqueue_struct		*submit_wq;
 	struct workqueue_struct		*timeout_wq;
-	struct work_struct		work_submit;
+	struct work_struct		work_run_job;
+	struct work_struct		work_free_job;
 	struct delayed_work		work_tdr;
 	struct list_head		pending_list;
 	spinlock_t			job_list_lock;
-- 
2.34.1

[PATCH v5 6/7] drm/sched: Add drm_sched_start_timeout_unlocked helper

[Matthew Brost]

Also add a lockdep assert to drm_sched_start_timeout.

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
---
 drivers/gpu/drm/scheduler/sched_main.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index cf4c23db7547..c4d5c3d265a8 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -427,11 +427,20 @@ static void drm_sched_job_done_cb(struct dma_fence *f, struct dma_fence_cb *cb)
  */
 static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
 {
+	lockdep_assert_held(&sched->job_list_lock);
+
 	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
 	    !list_empty(&sched->pending_list))
 		queue_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
 }
 
+static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
+{
+	spin_lock(&sched->job_list_lock);
+	drm_sched_start_timeout(sched);
+	spin_unlock(&sched->job_list_lock);
+}
+
 /**
  * drm_sched_fault - immediately start timeout handler
  *
@@ -544,11 +553,8 @@ static void drm_sched_job_timedout(struct work_struct *work)
 		spin_unlock(&sched->job_list_lock);
 	}
 
-	if (status != DRM_GPU_SCHED_STAT_ENODEV) {
-		spin_lock(&sched->job_list_lock);
-		drm_sched_start_timeout(sched);
-		spin_unlock(&sched->job_list_lock);
-	}
+	if (status != DRM_GPU_SCHED_STAT_ENODEV)
+		drm_sched_start_timeout_unlocked(sched);
 }
 
 /**
@@ -674,11 +680,8 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
 			drm_sched_job_done(s_job, -ECANCELED);
 	}
 
-	if (full_recovery) {
-		spin_lock(&sched->job_list_lock);
-		drm_sched_start_timeout(sched);
-		spin_unlock(&sched->job_list_lock);
-	}
+	if (full_recovery)
+		drm_sched_start_timeout_unlocked(sched);
 
 	drm_sched_wqueue_start(sched);
 }
-- 
2.34.1

[PATCH v5 7/7] drm/sched: Add helper to queue TDR immediately for current and future jobs

[Matthew Brost]

Add helper to queue TDR immediately for current and future jobs. This is
used in Xe, a new Intel GPU driver, to trigger a TDR to cleanup a
drm_scheduler that encounter errors.

v2:
 - Drop timeout args, rename function, use mod delayed work (Luben)
v3:
 - s/XE/Xe (Luben)
 - present tense in commit message (Luben)
 - Adjust comment for drm_sched_tdr_queue_imm (Luben)

Cc: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 drivers/gpu/drm/scheduler/sched_main.c | 18 +++++++++++++++++-
 include/drm/gpu_scheduler.h            |  1 +
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index c4d5c3d265a8..f2846745b067 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -431,7 +431,7 @@ static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
 
 	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
 	    !list_empty(&sched->pending_list))
-		queue_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
+		mod_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
 }
 
 static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
@@ -441,6 +441,22 @@ static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
 	spin_unlock(&sched->job_list_lock);
 }
 
+/**
+ * drm_sched_tdr_queue_imm: - immediately start job timeout handler
+ *
+ * @sched: scheduler for which the timeout handling should be started.
+ *
+ * Start timeout handling immediately for the named scheduler.
+ */
+void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched)
+{
+	spin_lock(&sched->job_list_lock);
+	sched->timeout = 0;
+	drm_sched_start_timeout(sched);
+	spin_unlock(&sched->job_list_lock);
+}
+EXPORT_SYMBOL(drm_sched_tdr_queue_imm);
+
 /**
  * drm_sched_fault - immediately start timeout handler
  *
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 625ffe040de3..998b32b8d212 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -568,6 +568,7 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
 				    struct drm_gpu_scheduler **sched_list,
                                    unsigned int num_sched_list);
 
+void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched);
 void drm_sched_job_cleanup(struct drm_sched_job *job);
 void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched);
 bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched);
-- 
2.34.1

Re: [PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> Rather than a global modparam for scheduling policy, move the scheduling
> policy to scheduler so user can control each scheduler policy.
> 
> v2:
>   - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
>   - Only include policy in scheduler (Luben)
> v3:
>   - use a ternary operator as opposed to an if-control (Luben)
>   - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
>   - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
>   - Update commit message (Boris)
>   - Fix v3d build (CI)
>   - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
>   - Don't update modparam doc (Luben)
> v4:
>   - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)
> 
> Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>

Was the R-V added by hand? (As in editing the commit message manually?)

I use automated tools for this which do not re-order the tags.
IOW, the S-O-B is first as this is how it appears in the patch,
then the R-V most probably added by automated tools, and then
any other as are tacked on by other automated tools.

This also shows the timeline of the tags and I believe this is
another one of the important facts tags show us.
-- 
Regards,
Luben


> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  1 +
>  drivers/gpu/drm/etnaviv/etnaviv_sched.c    |  3 ++-
>  drivers/gpu/drm/lima/lima_sched.c          |  3 ++-
>  drivers/gpu/drm/msm/msm_ringbuffer.c       |  2 +-
>  drivers/gpu/drm/nouveau/nouveau_sched.c    |  3 ++-
>  drivers/gpu/drm/panfrost/panfrost_job.c    |  3 ++-
>  drivers/gpu/drm/scheduler/sched_entity.c   | 24 ++++++++++++++++++----
>  drivers/gpu/drm/scheduler/sched_main.c     | 19 ++++++++++++-----
>  drivers/gpu/drm/v3d/v3d_sched.c            | 15 +++++++++-----
>  include/drm/gpu_scheduler.h                | 20 ++++++++++++------
>  10 files changed, 68 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index b54c4d771104..e4e6f91450a4 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -2283,6 +2283,7 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
>  				   ring->num_hw_submission, 0,
>  				   timeout, adev->reset_domain->wq,
>  				   ring->sched_score, ring->name,
> +				   DRM_SCHED_POLICY_UNSET,
>  				   adev->dev);
>  		if (r) {
>  			DRM_ERROR("Failed to create scheduler on ring %s.\n",
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> index 618a804ddc34..15b0e2f1abe5 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> @@ -137,7 +137,8 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
>  	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops, NULL,
>  			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
>  			     msecs_to_jiffies(500), NULL, NULL,
> -			     dev_name(gpu->dev), gpu->dev);
> +			     dev_name(gpu->dev), DRM_SCHED_POLICY_UNSET,
> +			     gpu->dev);
>  	if (ret)
>  		return ret;
>  
> diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
> index 8d858aed0e56..50c2075228aa 100644
> --- a/drivers/gpu/drm/lima/lima_sched.c
> +++ b/drivers/gpu/drm/lima/lima_sched.c
> @@ -491,7 +491,8 @@ int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
>  	return drm_sched_init(&pipe->base, &lima_sched_ops, NULL, 1,
>  			      lima_job_hang_limit,
>  			      msecs_to_jiffies(timeout), NULL,
> -			      NULL, name, pipe->ldev->dev);
> +			      NULL, name, DRM_SCHED_POLICY_UNSET,
> +			      pipe->ldev->dev);
>  }
>  
>  void lima_sched_pipe_fini(struct lima_sched_pipe *pipe)
> diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
> index 1097f8e93d6b..173ad2f17c50 100644
> --- a/drivers/gpu/drm/msm/msm_ringbuffer.c
> +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
> @@ -97,7 +97,7 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
>  	ret = drm_sched_init(&ring->sched, &msm_sched_ops, NULL,
>  			     num_hw_submissions, 0, sched_timeout,
>  			     NULL, NULL, to_msm_bo(ring->bo)->name,
> -			     gpu->dev->dev);
> +			     DRM_SCHED_POLICY_UNSET, gpu->dev->dev);
>  	if (ret) {
>  		goto fail;
>  	}
> diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
> index 4c959dec42b3..c4e09d2e77f9 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_sched.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
> @@ -437,7 +437,8 @@ int nouveau_sched_init(struct nouveau_drm *drm)
>  
>  	return drm_sched_init(sched, &nouveau_sched_ops, NULL,
>  			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
> -			      NULL, NULL, "nouveau_sched", drm->dev->dev);
> +			      NULL, NULL, "nouveau_sched",
> +			      DRM_SCHED_POLICY_UNSET, drm->dev->dev);
>  }
>  
>  void nouveau_sched_fini(struct nouveau_drm *drm)
> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
> index 934b7b930c76..95330ff402ba 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_job.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> @@ -856,7 +856,8 @@ int panfrost_job_init(struct panfrost_device *pfdev)
>  				     nentries, 0,
>  				     msecs_to_jiffies(JOB_TIMEOUT_MS),
>  				     pfdev->reset.wq,
> -				     NULL, "pan_js", pfdev->dev);
> +				     NULL, "pan_js", DRM_SCHED_POLICY_UNSET,
> +				     pfdev->dev);
>  		if (ret) {
>  			dev_err(pfdev->dev, "Failed to create scheduler: %d.", ret);
>  			goto err_sched;
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index a42763e1429d..cf42e2265d64 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -33,6 +33,20 @@
>  #define to_drm_sched_job(sched_job)		\
>  		container_of((sched_job), struct drm_sched_job, queue_node)
>  
> +static bool drm_sched_policy_mismatch(struct drm_gpu_scheduler **sched_list,
> +				      unsigned int num_sched_list)
> +{
> +	enum drm_sched_policy sched_policy = sched_list[0]->sched_policy;
> +	unsigned int i;
> +
> +	/* All schedule policies must match */
> +	for (i = 1; i < num_sched_list; ++i)
> +		if (sched_policy != sched_list[i]->sched_policy)
> +			return true;
> +
> +	return false;
> +}
> +
>  /**
>   * drm_sched_entity_init - Init a context entity used by scheduler when
>   * submit to HW ring.
> @@ -62,7 +76,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>  			  unsigned int num_sched_list,
>  			  atomic_t *guilty)
>  {
> -	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])))
> +	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])) ||
> +	    drm_sched_policy_mismatch(sched_list, num_sched_list))
>  		return -EINVAL;
>  
>  	memset(entity, 0, sizeof(struct drm_sched_entity));
> @@ -486,7 +501,7 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>  	 * Update the entity's location in the min heap according to
>  	 * the timestamp of the next job, if any.
>  	 */
> -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) {
> +	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
>  		struct drm_sched_job *next;
>  
>  		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
> @@ -558,7 +573,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
>  void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  {
>  	struct drm_sched_entity *entity = sched_job->entity;
> -	bool first;
> +	bool first, fifo = entity->rq->sched->sched_policy ==
> +		DRM_SCHED_POLICY_FIFO;
>  	ktime_t submit_ts;
>  
>  	trace_drm_sched_job(sched_job, entity);
> @@ -587,7 +603,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  		drm_sched_rq_add_entity(entity->rq, entity);
>  		spin_unlock(&entity->rq_lock);
>  
> -		if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> +		if (fifo)
>  			drm_sched_rq_update_fifo(entity, submit_ts);
>  
>  		drm_sched_wakeup_if_can_queue(entity->rq->sched);
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 8b1d52cff1e9..150e5330f0fa 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -66,14 +66,14 @@
>  #define to_drm_sched_job(sched_job)		\
>  		container_of((sched_job), struct drm_sched_job, queue_node)
>  
> -int drm_sched_policy = DRM_SCHED_POLICY_FIFO;
> +int drm_sched_policy_default = DRM_SCHED_POLICY_FIFO;
>  
>  /**
>   * DOC: sched_policy (int)
>   * Used to override default entities scheduling policy in a run queue.
>   */
>  MODULE_PARM_DESC(sched_policy, "Specify the scheduling policy for entities on a run-queue, " __stringify(DRM_SCHED_POLICY_RR) " = Round Robin, " __stringify(DRM_SCHED_POLICY_FIFO) " = FIFO (default).");
> -module_param_named(sched_policy, drm_sched_policy, int, 0444);
> +module_param_named(sched_policy, drm_sched_policy_default, int, 0444);
>  
>  static __always_inline bool drm_sched_entity_compare_before(struct rb_node *a,
>  							    const struct rb_node *b)
> @@ -177,7 +177,7 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
>  	if (rq->current_entity == entity)
>  		rq->current_entity = NULL;
>  
> -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> +	if (rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO)
>  		drm_sched_rq_remove_fifo_locked(entity);
>  
>  	spin_unlock(&rq->lock);
> @@ -898,7 +898,7 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
>  
>  	/* Kernel run queue has higher priority than normal run queue*/
>  	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> -		entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
> +		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
>  			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i]) :
>  			drm_sched_rq_select_entity_rr(&sched->sched_rq[i]);
>  		if (entity)
> @@ -1072,6 +1072,7 @@ static void drm_sched_main(struct work_struct *w)
>   *		used
>   * @score: optional score atomic shared with other schedulers
>   * @name: name used for debugging
> + * @sched_policy: schedule policy
>   * @dev: target &struct device
>   *
>   * Return 0 on success, otherwise error code.
> @@ -1081,9 +1082,15 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		   struct workqueue_struct *submit_wq,
>  		   unsigned hw_submission, unsigned hang_limit,
>  		   long timeout, struct workqueue_struct *timeout_wq,
> -		   atomic_t *score, const char *name, struct device *dev)
> +		   atomic_t *score, const char *name,
> +		   enum drm_sched_policy sched_policy,
> +		   struct device *dev)
>  {
>  	int i;
> +
> +	if (sched_policy >= DRM_SCHED_POLICY_COUNT)
> +		return -EINVAL;
> +
>  	sched->ops = ops;
>  	sched->hw_submission_limit = hw_submission;
>  	sched->name = name;
> @@ -1102,6 +1109,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  	sched->hang_limit = hang_limit;
>  	sched->score = score ? score : &sched->_score;
>  	sched->dev = dev;
> +	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
> +		drm_sched_policy_default : sched_policy;
>  	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
>  		drm_sched_rq_init(sched, &sched->sched_rq[i]);
>  
> diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
> index 38e092ea41e6..dec89c5b8cb1 100644
> --- a/drivers/gpu/drm/v3d/v3d_sched.c
> +++ b/drivers/gpu/drm/v3d/v3d_sched.c
> @@ -391,7 +391,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_bin_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_bin", v3d->drm.dev);
> +			     NULL, "v3d_bin", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		return ret;
>  
> @@ -399,7 +400,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_render_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_render", v3d->drm.dev);
> +			     NULL, "v3d_render", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		goto fail;
>  
> @@ -407,7 +409,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_tfu_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_tfu", v3d->drm.dev);
> +			     NULL, "v3d_tfu", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		goto fail;
>  
> @@ -416,7 +419,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  				     &v3d_csd_sched_ops, NULL,
>  				     hw_jobs_limit, job_hang_limit,
>  				     msecs_to_jiffies(hang_limit_ms), NULL,
> -				     NULL, "v3d_csd", v3d->drm.dev);
> +				     NULL, "v3d_csd", DRM_SCHED_POLICY_UNSET,
> +				     v3d->drm.dev);
>  		if (ret)
>  			goto fail;
>  
> @@ -424,7 +428,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  				     &v3d_cache_clean_sched_ops, NULL,
>  				     hw_jobs_limit, job_hang_limit,
>  				     msecs_to_jiffies(hang_limit_ms), NULL,
> -				     NULL, "v3d_cache_clean", v3d->drm.dev);
> +				     NULL, "v3d_cache_clean",
> +				     DRM_SCHED_POLICY_UNSET, v3d->drm.dev);
>  		if (ret)
>  			goto fail;
>  	}
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 211bd3cdabdc..320f0a720486 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -72,11 +72,15 @@ enum drm_sched_priority {
>  	DRM_SCHED_PRIORITY_UNSET = -2
>  };
>  
> -/* Used to chose between FIFO and RR jobs scheduling */
> -extern int drm_sched_policy;
> -
> -#define DRM_SCHED_POLICY_RR    0
> -#define DRM_SCHED_POLICY_FIFO  1
> +/* Used to chose default scheduling policy*/
> +extern int default_drm_sched_policy;
> +
> +enum drm_sched_policy {
> +	DRM_SCHED_POLICY_UNSET,
> +	DRM_SCHED_POLICY_RR,
> +	DRM_SCHED_POLICY_FIFO,
> +	DRM_SCHED_POLICY_COUNT,
> +};
>  
>  /**
>   * struct drm_sched_entity - A wrapper around a job queue (typically
> @@ -489,6 +493,7 @@ struct drm_sched_backend_ops {
>   *              guilty and it will no longer be considered for scheduling.
>   * @score: score to help loadbalancer pick a idle sched
>   * @_score: score used when the driver doesn't provide one
> + * @sched_policy: Schedule policy for scheduler
>   * @ready: marks if the underlying HW is ready to work
>   * @free_guilty: A hit to time out handler to free the guilty job.
>   * @pause_submit: pause queuing of @work_submit on @submit_wq
> @@ -515,6 +520,7 @@ struct drm_gpu_scheduler {
>  	int				hang_limit;
>  	atomic_t                        *score;
>  	atomic_t                        _score;
> +	enum drm_sched_policy		sched_policy;
>  	bool				ready;
>  	bool				free_guilty;
>  	bool				pause_submit;
> @@ -527,7 +533,9 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		   struct workqueue_struct *submit_wq,
>  		   uint32_t hw_submission, unsigned hang_limit,
>  		   long timeout, struct workqueue_struct *timeout_wq,
> -		   atomic_t *score, const char *name, struct device *dev);
> +		   atomic_t *score, const char *name,
> +		   enum drm_sched_policy sched_policy,
> +		   struct device *dev);
>  
>  void drm_sched_fini(struct drm_gpu_scheduler *sched);
>  int drm_sched_job_init(struct drm_sched_job *job,

Re: [PATCH v5 0/7] DRM scheduler changes for Xe

[Danilo Krummrich]

Hi Matt,

Can you please address my comments from V3 and V4?

https://lore.kernel.org/all/076891e9-b2ce-4c7f-833d-157aca5cd44b@amd.com/T/#m34ccee55e37ca47c87adf01439585d0bd187e3a0

- Danilo

On 10/12/23 01:58, Matthew Brost wrote:
> As a prerequisite to merging the new Intel Xe DRM driver [1] [2], we
> have been asked to merge our common DRM scheduler patches first.
> 
> This a continuation of a RFC [3] with all comments addressed, ready for
> a full review, and hopefully in state which can merged in the near
> future. More details of this series can found in the cover letter of the
> RFC [3].
> 
> These changes have been tested with the Xe driver.
> 
> v2:
>   - Break run job, free job, and process message in own work items
>   - This might break other drivers as run job and free job now can run in
>     parallel, can fix up if needed
> 
> v3:
>   - Include missing patch 'drm/sched: Add drm_sched_submit_* helpers'
>   - Fix issue with setting timestamp to early
>   - Don't dequeue jobs for single entity after calling entity fini
>   - Flush pending jobs on entity fini
>   - Add documentation for entity teardown
>   - Add Matthew Brost to maintainers of DRM scheduler
> 
> v4:
>   - Drop message interface
>   - Drop 'Flush pending jobs on entity fini'
>   - Drop 'Add documentation for entity teardown'
>   - Address all feedback
> 
> v5:
>   - Address Luben's feedback
>   - Drop starting TDR after calling run_job()
>   - Drop adding Matthew Brost to maintainers of DRM scheduler
> 
> Matt
> 
> [1] https://gitlab.freedesktop.org/drm/xe/kernel
> [2] https://patchwork.freedesktop.org/series/112188/
> [3] https://patchwork.freedesktop.org/series/116055/
> 
> Matthew Brost (7):
>    drm/sched: Add drm_sched_wqueue_* helpers
>    drm/sched: Convert drm scheduler to use a work queue rather than
>      kthread
>    drm/sched: Move schedule policy to scheduler
>    drm/sched: Add DRM_SCHED_POLICY_SINGLE_ENTITY scheduling policy
>    drm/sched: Split free_job into own work item
>    drm/sched: Add drm_sched_start_timeout_unlocked helper
>    drm/sched: Add helper to queue TDR immediately for current and future
>      jobs
> 
>   .../drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c   |   2 +-
>   drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c   |  15 +-
>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c    |  15 +-
>   drivers/gpu/drm/etnaviv/etnaviv_sched.c       |   5 +-
>   drivers/gpu/drm/lima/lima_sched.c             |   5 +-
>   drivers/gpu/drm/msm/adreno/adreno_device.c    |   6 +-
>   drivers/gpu/drm/msm/msm_ringbuffer.c          |   7 +-
>   drivers/gpu/drm/nouveau/nouveau_sched.c       |   5 +-
>   drivers/gpu/drm/panfrost/panfrost_job.c       |   5 +-
>   drivers/gpu/drm/scheduler/sched_entity.c      |  86 ++-
>   drivers/gpu/drm/scheduler/sched_fence.c       |   2 +-
>   drivers/gpu/drm/scheduler/sched_main.c        | 506 ++++++++++++------
>   drivers/gpu/drm/v3d/v3d_sched.c               |  25 +-
>   include/drm/gpu_scheduler.h                   |  48 +-
>   14 files changed, 499 insertions(+), 233 deletions(-)
> 

Re: [PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Matthew Brost]

On Wed, Oct 11, 2023 at 08:39:55PM -0400, Luben Tuikov wrote:
> On 2023-10-11 19:58, Matthew Brost wrote:
> > Rather than a global modparam for scheduling policy, move the scheduling
> > policy to scheduler so user can control each scheduler policy.
> > 
> > v2:
> >   - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
> >   - Only include policy in scheduler (Luben)
> > v3:
> >   - use a ternary operator as opposed to an if-control (Luben)
> >   - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
> >   - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
> >   - Update commit message (Boris)
> >   - Fix v3d build (CI)
> >   - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
> >   - Don't update modparam doc (Luben)
> > v4:
> >   - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)
> > 
> > Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
> > Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> 
> Was the R-V added by hand? (As in editing the commit message manually?)
> 

Yes.

> I use automated tools for this which do not re-order the tags.
> IOW, the S-O-B is first as this is how it appears in the patch,
> then the R-V most probably added by automated tools, and then
> any other as are tacked on by other automated tools.
>

Ok, so always add tags in order starting with S-O-B?

Matt

> This also shows the timeline of the tags and I believe this is
> another one of the important facts tags show us.
> -- 
> Regards,
> Luben
> 
> 
> > ---
> >  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  1 +
> >  drivers/gpu/drm/etnaviv/etnaviv_sched.c    |  3 ++-
> >  drivers/gpu/drm/lima/lima_sched.c          |  3 ++-
> >  drivers/gpu/drm/msm/msm_ringbuffer.c       |  2 +-
> >  drivers/gpu/drm/nouveau/nouveau_sched.c    |  3 ++-
> >  drivers/gpu/drm/panfrost/panfrost_job.c    |  3 ++-
> >  drivers/gpu/drm/scheduler/sched_entity.c   | 24 ++++++++++++++++++----
> >  drivers/gpu/drm/scheduler/sched_main.c     | 19 ++++++++++++-----
> >  drivers/gpu/drm/v3d/v3d_sched.c            | 15 +++++++++-----
> >  include/drm/gpu_scheduler.h                | 20 ++++++++++++------
> >  10 files changed, 68 insertions(+), 25 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > index b54c4d771104..e4e6f91450a4 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > @@ -2283,6 +2283,7 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
> >  				   ring->num_hw_submission, 0,
> >  				   timeout, adev->reset_domain->wq,
> >  				   ring->sched_score, ring->name,
> > +				   DRM_SCHED_POLICY_UNSET,
> >  				   adev->dev);
> >  		if (r) {
> >  			DRM_ERROR("Failed to create scheduler on ring %s.\n",
> > diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> > index 618a804ddc34..15b0e2f1abe5 100644
> > --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> > +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> > @@ -137,7 +137,8 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
> >  	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops, NULL,
> >  			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
> >  			     msecs_to_jiffies(500), NULL, NULL,
> > -			     dev_name(gpu->dev), gpu->dev);
> > +			     dev_name(gpu->dev), DRM_SCHED_POLICY_UNSET,
> > +			     gpu->dev);
> >  	if (ret)
> >  		return ret;
> >  
> > diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
> > index 8d858aed0e56..50c2075228aa 100644
> > --- a/drivers/gpu/drm/lima/lima_sched.c
> > +++ b/drivers/gpu/drm/lima/lima_sched.c
> > @@ -491,7 +491,8 @@ int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
> >  	return drm_sched_init(&pipe->base, &lima_sched_ops, NULL, 1,
> >  			      lima_job_hang_limit,
> >  			      msecs_to_jiffies(timeout), NULL,
> > -			      NULL, name, pipe->ldev->dev);
> > +			      NULL, name, DRM_SCHED_POLICY_UNSET,
> > +			      pipe->ldev->dev);
> >  }
> >  
> >  void lima_sched_pipe_fini(struct lima_sched_pipe *pipe)
> > diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
> > index 1097f8e93d6b..173ad2f17c50 100644
> > --- a/drivers/gpu/drm/msm/msm_ringbuffer.c
> > +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
> > @@ -97,7 +97,7 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
> >  	ret = drm_sched_init(&ring->sched, &msm_sched_ops, NULL,
> >  			     num_hw_submissions, 0, sched_timeout,
> >  			     NULL, NULL, to_msm_bo(ring->bo)->name,
> > -			     gpu->dev->dev);
> > +			     DRM_SCHED_POLICY_UNSET, gpu->dev->dev);
> >  	if (ret) {
> >  		goto fail;
> >  	}
> > diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
> > index 4c959dec42b3..c4e09d2e77f9 100644
> > --- a/drivers/gpu/drm/nouveau/nouveau_sched.c
> > +++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
> > @@ -437,7 +437,8 @@ int nouveau_sched_init(struct nouveau_drm *drm)
> >  
> >  	return drm_sched_init(sched, &nouveau_sched_ops, NULL,
> >  			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
> > -			      NULL, NULL, "nouveau_sched", drm->dev->dev);
> > +			      NULL, NULL, "nouveau_sched",
> > +			      DRM_SCHED_POLICY_UNSET, drm->dev->dev);
> >  }
> >  
> >  void nouveau_sched_fini(struct nouveau_drm *drm)
> > diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
> > index 934b7b930c76..95330ff402ba 100644
> > --- a/drivers/gpu/drm/panfrost/panfrost_job.c
> > +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> > @@ -856,7 +856,8 @@ int panfrost_job_init(struct panfrost_device *pfdev)
> >  				     nentries, 0,
> >  				     msecs_to_jiffies(JOB_TIMEOUT_MS),
> >  				     pfdev->reset.wq,
> > -				     NULL, "pan_js", pfdev->dev);
> > +				     NULL, "pan_js", DRM_SCHED_POLICY_UNSET,
> > +				     pfdev->dev);
> >  		if (ret) {
> >  			dev_err(pfdev->dev, "Failed to create scheduler: %d.", ret);
> >  			goto err_sched;
> > diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> > index a42763e1429d..cf42e2265d64 100644
> > --- a/drivers/gpu/drm/scheduler/sched_entity.c
> > +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> > @@ -33,6 +33,20 @@
> >  #define to_drm_sched_job(sched_job)		\
> >  		container_of((sched_job), struct drm_sched_job, queue_node)
> >  
> > +static bool drm_sched_policy_mismatch(struct drm_gpu_scheduler **sched_list,
> > +				      unsigned int num_sched_list)
> > +{
> > +	enum drm_sched_policy sched_policy = sched_list[0]->sched_policy;
> > +	unsigned int i;
> > +
> > +	/* All schedule policies must match */
> > +	for (i = 1; i < num_sched_list; ++i)
> > +		if (sched_policy != sched_list[i]->sched_policy)
> > +			return true;
> > +
> > +	return false;
> > +}
> > +
> >  /**
> >   * drm_sched_entity_init - Init a context entity used by scheduler when
> >   * submit to HW ring.
> > @@ -62,7 +76,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
> >  			  unsigned int num_sched_list,
> >  			  atomic_t *guilty)
> >  {
> > -	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])))
> > +	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])) ||
> > +	    drm_sched_policy_mismatch(sched_list, num_sched_list))
> >  		return -EINVAL;
> >  
> >  	memset(entity, 0, sizeof(struct drm_sched_entity));
> > @@ -486,7 +501,7 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
> >  	 * Update the entity's location in the min heap according to
> >  	 * the timestamp of the next job, if any.
> >  	 */
> > -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) {
> > +	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
> >  		struct drm_sched_job *next;
> >  
> >  		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
> > @@ -558,7 +573,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
> >  void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
> >  {
> >  	struct drm_sched_entity *entity = sched_job->entity;
> > -	bool first;
> > +	bool first, fifo = entity->rq->sched->sched_policy ==
> > +		DRM_SCHED_POLICY_FIFO;
> >  	ktime_t submit_ts;
> >  
> >  	trace_drm_sched_job(sched_job, entity);
> > @@ -587,7 +603,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
> >  		drm_sched_rq_add_entity(entity->rq, entity);
> >  		spin_unlock(&entity->rq_lock);
> >  
> > -		if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> > +		if (fifo)
> >  			drm_sched_rq_update_fifo(entity, submit_ts);
> >  
> >  		drm_sched_wakeup_if_can_queue(entity->rq->sched);
> > diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> > index 8b1d52cff1e9..150e5330f0fa 100644
> > --- a/drivers/gpu/drm/scheduler/sched_main.c
> > +++ b/drivers/gpu/drm/scheduler/sched_main.c
> > @@ -66,14 +66,14 @@
> >  #define to_drm_sched_job(sched_job)		\
> >  		container_of((sched_job), struct drm_sched_job, queue_node)
> >  
> > -int drm_sched_policy = DRM_SCHED_POLICY_FIFO;
> > +int drm_sched_policy_default = DRM_SCHED_POLICY_FIFO;
> >  
> >  /**
> >   * DOC: sched_policy (int)
> >   * Used to override default entities scheduling policy in a run queue.
> >   */
> >  MODULE_PARM_DESC(sched_policy, "Specify the scheduling policy for entities on a run-queue, " __stringify(DRM_SCHED_POLICY_RR) " = Round Robin, " __stringify(DRM_SCHED_POLICY_FIFO) " = FIFO (default).");
> > -module_param_named(sched_policy, drm_sched_policy, int, 0444);
> > +module_param_named(sched_policy, drm_sched_policy_default, int, 0444);
> >  
> >  static __always_inline bool drm_sched_entity_compare_before(struct rb_node *a,
> >  							    const struct rb_node *b)
> > @@ -177,7 +177,7 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
> >  	if (rq->current_entity == entity)
> >  		rq->current_entity = NULL;
> >  
> > -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> > +	if (rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO)
> >  		drm_sched_rq_remove_fifo_locked(entity);
> >  
> >  	spin_unlock(&rq->lock);
> > @@ -898,7 +898,7 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
> >  
> >  	/* Kernel run queue has higher priority than normal run queue*/
> >  	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> > -		entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
> > +		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
> >  			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i]) :
> >  			drm_sched_rq_select_entity_rr(&sched->sched_rq[i]);
> >  		if (entity)
> > @@ -1072,6 +1072,7 @@ static void drm_sched_main(struct work_struct *w)
> >   *		used
> >   * @score: optional score atomic shared with other schedulers
> >   * @name: name used for debugging
> > + * @sched_policy: schedule policy
> >   * @dev: target &struct device
> >   *
> >   * Return 0 on success, otherwise error code.
> > @@ -1081,9 +1082,15 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> >  		   struct workqueue_struct *submit_wq,
> >  		   unsigned hw_submission, unsigned hang_limit,
> >  		   long timeout, struct workqueue_struct *timeout_wq,
> > -		   atomic_t *score, const char *name, struct device *dev)
> > +		   atomic_t *score, const char *name,
> > +		   enum drm_sched_policy sched_policy,
> > +		   struct device *dev)
> >  {
> >  	int i;
> > +
> > +	if (sched_policy >= DRM_SCHED_POLICY_COUNT)
> > +		return -EINVAL;
> > +
> >  	sched->ops = ops;
> >  	sched->hw_submission_limit = hw_submission;
> >  	sched->name = name;
> > @@ -1102,6 +1109,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> >  	sched->hang_limit = hang_limit;
> >  	sched->score = score ? score : &sched->_score;
> >  	sched->dev = dev;
> > +	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
> > +		drm_sched_policy_default : sched_policy;
> >  	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
> >  		drm_sched_rq_init(sched, &sched->sched_rq[i]);
> >  
> > diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
> > index 38e092ea41e6..dec89c5b8cb1 100644
> > --- a/drivers/gpu/drm/v3d/v3d_sched.c
> > +++ b/drivers/gpu/drm/v3d/v3d_sched.c
> > @@ -391,7 +391,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  			     &v3d_bin_sched_ops, NULL,
> >  			     hw_jobs_limit, job_hang_limit,
> >  			     msecs_to_jiffies(hang_limit_ms), NULL,
> > -			     NULL, "v3d_bin", v3d->drm.dev);
> > +			     NULL, "v3d_bin", DRM_SCHED_POLICY_UNSET,
> > +			     v3d->drm.dev);
> >  	if (ret)
> >  		return ret;
> >  
> > @@ -399,7 +400,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  			     &v3d_render_sched_ops, NULL,
> >  			     hw_jobs_limit, job_hang_limit,
> >  			     msecs_to_jiffies(hang_limit_ms), NULL,
> > -			     NULL, "v3d_render", v3d->drm.dev);
> > +			     NULL, "v3d_render", DRM_SCHED_POLICY_UNSET,
> > +			     v3d->drm.dev);
> >  	if (ret)
> >  		goto fail;
> >  
> > @@ -407,7 +409,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  			     &v3d_tfu_sched_ops, NULL,
> >  			     hw_jobs_limit, job_hang_limit,
> >  			     msecs_to_jiffies(hang_limit_ms), NULL,
> > -			     NULL, "v3d_tfu", v3d->drm.dev);
> > +			     NULL, "v3d_tfu", DRM_SCHED_POLICY_UNSET,
> > +			     v3d->drm.dev);
> >  	if (ret)
> >  		goto fail;
> >  
> > @@ -416,7 +419,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  				     &v3d_csd_sched_ops, NULL,
> >  				     hw_jobs_limit, job_hang_limit,
> >  				     msecs_to_jiffies(hang_limit_ms), NULL,
> > -				     NULL, "v3d_csd", v3d->drm.dev);
> > +				     NULL, "v3d_csd", DRM_SCHED_POLICY_UNSET,
> > +				     v3d->drm.dev);
> >  		if (ret)
> >  			goto fail;
> >  
> > @@ -424,7 +428,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  				     &v3d_cache_clean_sched_ops, NULL,
> >  				     hw_jobs_limit, job_hang_limit,
> >  				     msecs_to_jiffies(hang_limit_ms), NULL,
> > -				     NULL, "v3d_cache_clean", v3d->drm.dev);
> > +				     NULL, "v3d_cache_clean",
> > +				     DRM_SCHED_POLICY_UNSET, v3d->drm.dev);
> >  		if (ret)
> >  			goto fail;
> >  	}
> > diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> > index 211bd3cdabdc..320f0a720486 100644
> > --- a/include/drm/gpu_scheduler.h
> > +++ b/include/drm/gpu_scheduler.h
> > @@ -72,11 +72,15 @@ enum drm_sched_priority {
> >  	DRM_SCHED_PRIORITY_UNSET = -2
> >  };
> >  
> > -/* Used to chose between FIFO and RR jobs scheduling */
> > -extern int drm_sched_policy;
> > -
> > -#define DRM_SCHED_POLICY_RR    0
> > -#define DRM_SCHED_POLICY_FIFO  1
> > +/* Used to chose default scheduling policy*/
> > +extern int default_drm_sched_policy;
> > +
> > +enum drm_sched_policy {
> > +	DRM_SCHED_POLICY_UNSET,
> > +	DRM_SCHED_POLICY_RR,
> > +	DRM_SCHED_POLICY_FIFO,
> > +	DRM_SCHED_POLICY_COUNT,
> > +};
> >  
> >  /**
> >   * struct drm_sched_entity - A wrapper around a job queue (typically
> > @@ -489,6 +493,7 @@ struct drm_sched_backend_ops {
> >   *              guilty and it will no longer be considered for scheduling.
> >   * @score: score to help loadbalancer pick a idle sched
> >   * @_score: score used when the driver doesn't provide one
> > + * @sched_policy: Schedule policy for scheduler
> >   * @ready: marks if the underlying HW is ready to work
> >   * @free_guilty: A hit to time out handler to free the guilty job.
> >   * @pause_submit: pause queuing of @work_submit on @submit_wq
> > @@ -515,6 +520,7 @@ struct drm_gpu_scheduler {
> >  	int				hang_limit;
> >  	atomic_t                        *score;
> >  	atomic_t                        _score;
> > +	enum drm_sched_policy		sched_policy;
> >  	bool				ready;
> >  	bool				free_guilty;
> >  	bool				pause_submit;
> > @@ -527,7 +533,9 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> >  		   struct workqueue_struct *submit_wq,
> >  		   uint32_t hw_submission, unsigned hang_limit,
> >  		   long timeout, struct workqueue_struct *timeout_wq,
> > -		   atomic_t *score, const char *name, struct device *dev);
> > +		   atomic_t *score, const char *name,
> > +		   enum drm_sched_policy sched_policy,
> > +		   struct device *dev);
> >  
> >  void drm_sched_fini(struct drm_gpu_scheduler *sched);
> >  int drm_sched_job_init(struct drm_sched_job *job,
> 

Re: [PATCH v5 0/7] DRM scheduler changes for Xe

[Matthew Brost]

On Thu, Oct 12, 2023 at 04:02:13AM +0200, Danilo Krummrich wrote:
> Hi Matt,
> 
> Can you please address my comments from V3 and V4?
> 
> https://lore.kernel.org/all/076891e9-b2ce-4c7f-833d-157aca5cd44b@amd.com/T/#m34ccee55e37ca47c87adf01439585d0bd187e3a0
> 

Not my intent to ignore you. To be clear I need to address this comment:

'There is some feedback from V3 that doesn't seem to be addressed yet.

(1) Document tear down of struct drm_gpu_scheduler. [1]
(2) Implement helpers to tear down struct drm_gpu_scheduler. [2]
(3) Document implications of using a workqueue in terms of free_job() being
     or not being part of the fence signaling path respectively. [3]

I think at least (1) and (3) should be part of this series. I think (2) could
also happen subsequently. Christian's idea [2] how to address this is quite
interesting, but might exceed the scope of this series.

I will try to rebase my Nouveau changes onto your V4 tomorrow for a quick test.

- Danilo

[1] https://lore.kernel.org/all/20230912021615.2086698-1-matthew.brost@intel.com/T/#m2e8c1c1e68e8127d5dd62509b5e424a12217300b
[2] https://lore.kernel.org/all/20230912021615.2086698-1-matthew.brost@intel.com/T/#m16a0d6fa2e617383776515af45d3c6b9db543d47
[3] https://lore.kernel.org/all/20230912021615.2086698-1-matthew.brost@intel.com/T/#m807ff95284089fdb51985f1c187666772314bd8a'

Matt

> - Danilo
> 
> On 10/12/23 01:58, Matthew Brost wrote:
> > As a prerequisite to merging the new Intel Xe DRM driver [1] [2], we
> > have been asked to merge our common DRM scheduler patches first.
> > 
> > This a continuation of a RFC [3] with all comments addressed, ready for
> > a full review, and hopefully in state which can merged in the near
> > future. More details of this series can found in the cover letter of the
> > RFC [3].
> > 
> > These changes have been tested with the Xe driver.
> > 
> > v2:
> >   - Break run job, free job, and process message in own work items
> >   - This might break other drivers as run job and free job now can run in
> >     parallel, can fix up if needed
> > 
> > v3:
> >   - Include missing patch 'drm/sched: Add drm_sched_submit_* helpers'
> >   - Fix issue with setting timestamp to early
> >   - Don't dequeue jobs for single entity after calling entity fini
> >   - Flush pending jobs on entity fini
> >   - Add documentation for entity teardown
> >   - Add Matthew Brost to maintainers of DRM scheduler
> > 
> > v4:
> >   - Drop message interface
> >   - Drop 'Flush pending jobs on entity fini'
> >   - Drop 'Add documentation for entity teardown'
> >   - Address all feedback
> > 
> > v5:
> >   - Address Luben's feedback
> >   - Drop starting TDR after calling run_job()
> >   - Drop adding Matthew Brost to maintainers of DRM scheduler
> > 
> > Matt
> > 
> > [1] https://gitlab.freedesktop.org/drm/xe/kernel
> > [2] https://patchwork.freedesktop.org/series/112188/
> > [3] https://patchwork.freedesktop.org/series/116055/
> > 
> > Matthew Brost (7):
> >    drm/sched: Add drm_sched_wqueue_* helpers
> >    drm/sched: Convert drm scheduler to use a work queue rather than
> >      kthread
> >    drm/sched: Move schedule policy to scheduler
> >    drm/sched: Add DRM_SCHED_POLICY_SINGLE_ENTITY scheduling policy
> >    drm/sched: Split free_job into own work item
> >    drm/sched: Add drm_sched_start_timeout_unlocked helper
> >    drm/sched: Add helper to queue TDR immediately for current and future
> >      jobs
> > 
> >   .../drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c   |   2 +-
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c   |  15 +-
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c    |  15 +-
> >   drivers/gpu/drm/etnaviv/etnaviv_sched.c       |   5 +-
> >   drivers/gpu/drm/lima/lima_sched.c             |   5 +-
> >   drivers/gpu/drm/msm/adreno/adreno_device.c    |   6 +-
> >   drivers/gpu/drm/msm/msm_ringbuffer.c          |   7 +-
> >   drivers/gpu/drm/nouveau/nouveau_sched.c       |   5 +-
> >   drivers/gpu/drm/panfrost/panfrost_job.c       |   5 +-
> >   drivers/gpu/drm/scheduler/sched_entity.c      |  86 ++-
> >   drivers/gpu/drm/scheduler/sched_fence.c       |   2 +-
> >   drivers/gpu/drm/scheduler/sched_main.c        | 506 ++++++++++++------
> >   drivers/gpu/drm/v3d/v3d_sched.c               |  25 +-
> >   include/drm/gpu_scheduler.h                   |  48 +-
> >   14 files changed, 499 insertions(+), 233 deletions(-)
> > 
> 

Re: [PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Luben Tuikov]

On 2023-10-12 00:31, Matthew Brost wrote:
> On Wed, Oct 11, 2023 at 08:39:55PM -0400, Luben Tuikov wrote:
>> On 2023-10-11 19:58, Matthew Brost wrote:
>>> Rather than a global modparam for scheduling policy, move the scheduling
>>> policy to scheduler so user can control each scheduler policy.
>>>
>>> v2:
>>>   - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
>>>   - Only include policy in scheduler (Luben)
>>> v3:
>>>   - use a ternary operator as opposed to an if-control (Luben)
>>>   - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
>>>   - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
>>>   - Update commit message (Boris)
>>>   - Fix v3d build (CI)
>>>   - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
>>>   - Don't update modparam doc (Luben)
>>> v4:
>>>   - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)
>>>
>>> Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
>>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
>>
>> Was the R-V added by hand? (As in editing the commit message manually?)
>>
> 
> Yes.
> 
>> I use automated tools for this which do not re-order the tags.
>> IOW, the S-O-B is first as this is how it appears in the patch,
>> then the R-V most probably added by automated tools, and then
>> any other as are tacked on by other automated tools.
>>
> 
> Ok, so always add tags in order starting with S-O-B?

Yes!

The S-O-B tag you add when you write the commit and then you post
it up to a mailing list, it's mandatory and it's always there.
It's most likely the first, top tag.

Then various other scripts and tools start adding tags in an automated way,
and those tags are just appended below any existing tags.

Generally, always follow a natural order (meaning least amount of energy
expenditure--if you have to edit to reorder, that is extra energy expenditure
and nature doesn't like that). Make it like a letter you'd get from or write to
your bank, attorney, etc.
	These are tags you add when you craft your commit:
Cc: goes first, followed by other tags whose values
Cc: are personal emails, i.e. people. These are people
Cc: you want to let know of this commit. This is followed
Cc: by other personal tags, for instance,
Co-developed-by: or
Suggested-by: Another personal tag is,
Reported-by: which must be followed by a Link tag with
Link: the link of the report. This could also be a link to anything else. You can also add a
Fixes: tag which should follow a --pretty %h (\"%s\") format.
Closes: link to the bug the patch closes
Signed-off-by: You
	Then scripts and tools (or even people) would append the tag list with:
Tested-by: someone reliable, could have more than one instance of this tag,
Acked-by: someone
Reviewed-by: someone

There are no empty lines between tags. They form a block paragraph as they would
if/when added by a script. (I never add _any_ tag manually.)

So, for instance, you may have:

Cc: Luben
Signed-off-by: Matt

And when the patch is R-V-ed this becomes (least amount of energy, append at the bottom),

Cc: Luben
Signed-off-by: Matt
Reviewed-by: Luben

Then other tags may be appended, depending on the path the patch takes to land in a tree.

Check out:
https://docs.kernel.org/process/5.Posting.html
https://docs.kernel.org/process/submitting-patches.html
https://docs.kernel.org/process/submit-checklist.html
And there's more resources to check out in the Documentation/process directory.
-- 
Regards,
Luben

Re: [PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> Rather than a global modparam for scheduling policy, move the scheduling
> policy to scheduler so user can control each scheduler policy.
> 
> v2:
>   - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
>   - Only include policy in scheduler (Luben)
> v3:
>   - use a ternary operator as opposed to an if-control (Luben)
>   - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
>   - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
>   - Update commit message (Boris)
>   - Fix v3d build (CI)
>   - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
>   - Don't update modparam doc (Luben)
> v4:
>   - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)
> 
> Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>

Hi,

Forgot to mention this, but it is a very important process to note,
is that one should _never_ add someone else's R-V tag, _*UNLESS*_
a) there's an email from the person giving their review or ack, and
b) you're the one pushing the patch set into the tree.
If you're not the one pushing it into the tree, the maintainer will
add their R-V (after their reply-to follow-up email--see below),
including a Link: tag when they do "git am" after it's been all reviewed.

And there's a reason for this.

The reason is that when kernel maintainers (especially DRM via dim[1]) push
patches into the kernel, we want to add a Link: tag [2,3] pointing to
the thread where a) the patch was posted and b) where the reviewer gave
their Reviewed-by to the patch in a reply-all email, and at this moment
there is no such email for this patch.

When a maintainer says "Do X, Y, Z, for an immediate R-V", this means
do those things, post it, and get a reply from the maintainer with an
R-V. This records how it happened and is very helpful when doing
data mining on how and why the code changed, via what patches, etc.

I suspect there might be a v6, and we can do the R-V/Ack the right way
at that time. No big deal, but it's good to know in one place as it
is a bit scatter here and there in the kernel-doc.

[1] https://gitlab.freedesktop.org/drm/maintainer-tools/
[2] git am --message-id
[3] https://docs.kernel.org/maintainer/
-- 
Regards,
Luben

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  1 +
>  drivers/gpu/drm/etnaviv/etnaviv_sched.c    |  3 ++-
>  drivers/gpu/drm/lima/lima_sched.c          |  3 ++-
>  drivers/gpu/drm/msm/msm_ringbuffer.c       |  2 +-
>  drivers/gpu/drm/nouveau/nouveau_sched.c    |  3 ++-
>  drivers/gpu/drm/panfrost/panfrost_job.c    |  3 ++-
>  drivers/gpu/drm/scheduler/sched_entity.c   | 24 ++++++++++++++++++----
>  drivers/gpu/drm/scheduler/sched_main.c     | 19 ++++++++++++-----
>  drivers/gpu/drm/v3d/v3d_sched.c            | 15 +++++++++-----
>  include/drm/gpu_scheduler.h                | 20 ++++++++++++------
>  10 files changed, 68 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index b54c4d771104..e4e6f91450a4 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -2283,6 +2283,7 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
>  				   ring->num_hw_submission, 0,
>  				   timeout, adev->reset_domain->wq,
>  				   ring->sched_score, ring->name,
> +				   DRM_SCHED_POLICY_UNSET,
>  				   adev->dev);
>  		if (r) {
>  			DRM_ERROR("Failed to create scheduler on ring %s.\n",
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> index 618a804ddc34..15b0e2f1abe5 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> @@ -137,7 +137,8 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
>  	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops, NULL,
>  			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
>  			     msecs_to_jiffies(500), NULL, NULL,
> -			     dev_name(gpu->dev), gpu->dev);
> +			     dev_name(gpu->dev), DRM_SCHED_POLICY_UNSET,
> +			     gpu->dev);
>  	if (ret)
>  		return ret;
>  
> diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
> index 8d858aed0e56..50c2075228aa 100644
> --- a/drivers/gpu/drm/lima/lima_sched.c
> +++ b/drivers/gpu/drm/lima/lima_sched.c
> @@ -491,7 +491,8 @@ int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
>  	return drm_sched_init(&pipe->base, &lima_sched_ops, NULL, 1,
>  			      lima_job_hang_limit,
>  			      msecs_to_jiffies(timeout), NULL,
> -			      NULL, name, pipe->ldev->dev);
> +			      NULL, name, DRM_SCHED_POLICY_UNSET,
> +			      pipe->ldev->dev);
>  }
>  
>  void lima_sched_pipe_fini(struct lima_sched_pipe *pipe)
> diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
> index 1097f8e93d6b..173ad2f17c50 100644
> --- a/drivers/gpu/drm/msm/msm_ringbuffer.c
> +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
> @@ -97,7 +97,7 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
>  	ret = drm_sched_init(&ring->sched, &msm_sched_ops, NULL,
>  			     num_hw_submissions, 0, sched_timeout,
>  			     NULL, NULL, to_msm_bo(ring->bo)->name,
> -			     gpu->dev->dev);
> +			     DRM_SCHED_POLICY_UNSET, gpu->dev->dev);
>  	if (ret) {
>  		goto fail;
>  	}
> diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
> index 4c959dec42b3..c4e09d2e77f9 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_sched.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
> @@ -437,7 +437,8 @@ int nouveau_sched_init(struct nouveau_drm *drm)
>  
>  	return drm_sched_init(sched, &nouveau_sched_ops, NULL,
>  			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
> -			      NULL, NULL, "nouveau_sched", drm->dev->dev);
> +			      NULL, NULL, "nouveau_sched",
> +			      DRM_SCHED_POLICY_UNSET, drm->dev->dev);
>  }
>  
>  void nouveau_sched_fini(struct nouveau_drm *drm)
> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
> index 934b7b930c76..95330ff402ba 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_job.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> @@ -856,7 +856,8 @@ int panfrost_job_init(struct panfrost_device *pfdev)
>  				     nentries, 0,
>  				     msecs_to_jiffies(JOB_TIMEOUT_MS),
>  				     pfdev->reset.wq,
> -				     NULL, "pan_js", pfdev->dev);
> +				     NULL, "pan_js", DRM_SCHED_POLICY_UNSET,
> +				     pfdev->dev);
>  		if (ret) {
>  			dev_err(pfdev->dev, "Failed to create scheduler: %d.", ret);
>  			goto err_sched;
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index a42763e1429d..cf42e2265d64 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -33,6 +33,20 @@
>  #define to_drm_sched_job(sched_job)		\
>  		container_of((sched_job), struct drm_sched_job, queue_node)
>  
> +static bool drm_sched_policy_mismatch(struct drm_gpu_scheduler **sched_list,
> +				      unsigned int num_sched_list)
> +{
> +	enum drm_sched_policy sched_policy = sched_list[0]->sched_policy;
> +	unsigned int i;
> +
> +	/* All schedule policies must match */
> +	for (i = 1; i < num_sched_list; ++i)
> +		if (sched_policy != sched_list[i]->sched_policy)
> +			return true;
> +
> +	return false;
> +}
> +
>  /**
>   * drm_sched_entity_init - Init a context entity used by scheduler when
>   * submit to HW ring.
> @@ -62,7 +76,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>  			  unsigned int num_sched_list,
>  			  atomic_t *guilty)
>  {
> -	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])))
> +	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])) ||
> +	    drm_sched_policy_mismatch(sched_list, num_sched_list))
>  		return -EINVAL;
>  
>  	memset(entity, 0, sizeof(struct drm_sched_entity));
> @@ -486,7 +501,7 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>  	 * Update the entity's location in the min heap according to
>  	 * the timestamp of the next job, if any.
>  	 */
> -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) {
> +	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
>  		struct drm_sched_job *next;
>  
>  		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
> @@ -558,7 +573,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
>  void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  {
>  	struct drm_sched_entity *entity = sched_job->entity;
> -	bool first;
> +	bool first, fifo = entity->rq->sched->sched_policy ==
> +		DRM_SCHED_POLICY_FIFO;
>  	ktime_t submit_ts;
>  
>  	trace_drm_sched_job(sched_job, entity);
> @@ -587,7 +603,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  		drm_sched_rq_add_entity(entity->rq, entity);
>  		spin_unlock(&entity->rq_lock);
>  
> -		if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> +		if (fifo)
>  			drm_sched_rq_update_fifo(entity, submit_ts);
>  
>  		drm_sched_wakeup_if_can_queue(entity->rq->sched);
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 8b1d52cff1e9..150e5330f0fa 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -66,14 +66,14 @@
>  #define to_drm_sched_job(sched_job)		\
>  		container_of((sched_job), struct drm_sched_job, queue_node)
>  
> -int drm_sched_policy = DRM_SCHED_POLICY_FIFO;
> +int drm_sched_policy_default = DRM_SCHED_POLICY_FIFO;
>  
>  /**
>   * DOC: sched_policy (int)
>   * Used to override default entities scheduling policy in a run queue.
>   */
>  MODULE_PARM_DESC(sched_policy, "Specify the scheduling policy for entities on a run-queue, " __stringify(DRM_SCHED_POLICY_RR) " = Round Robin, " __stringify(DRM_SCHED_POLICY_FIFO) " = FIFO (default).");
> -module_param_named(sched_policy, drm_sched_policy, int, 0444);
> +module_param_named(sched_policy, drm_sched_policy_default, int, 0444);
>  
>  static __always_inline bool drm_sched_entity_compare_before(struct rb_node *a,
>  							    const struct rb_node *b)
> @@ -177,7 +177,7 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
>  	if (rq->current_entity == entity)
>  		rq->current_entity = NULL;
>  
> -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> +	if (rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO)
>  		drm_sched_rq_remove_fifo_locked(entity);
>  
>  	spin_unlock(&rq->lock);
> @@ -898,7 +898,7 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
>  
>  	/* Kernel run queue has higher priority than normal run queue*/
>  	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> -		entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
> +		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
>  			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i]) :
>  			drm_sched_rq_select_entity_rr(&sched->sched_rq[i]);
>  		if (entity)
> @@ -1072,6 +1072,7 @@ static void drm_sched_main(struct work_struct *w)
>   *		used
>   * @score: optional score atomic shared with other schedulers
>   * @name: name used for debugging
> + * @sched_policy: schedule policy
>   * @dev: target &struct device
>   *
>   * Return 0 on success, otherwise error code.
> @@ -1081,9 +1082,15 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		   struct workqueue_struct *submit_wq,
>  		   unsigned hw_submission, unsigned hang_limit,
>  		   long timeout, struct workqueue_struct *timeout_wq,
> -		   atomic_t *score, const char *name, struct device *dev)
> +		   atomic_t *score, const char *name,
> +		   enum drm_sched_policy sched_policy,
> +		   struct device *dev)
>  {
>  	int i;
> +
> +	if (sched_policy >= DRM_SCHED_POLICY_COUNT)
> +		return -EINVAL;
> +
>  	sched->ops = ops;
>  	sched->hw_submission_limit = hw_submission;
>  	sched->name = name;
> @@ -1102,6 +1109,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  	sched->hang_limit = hang_limit;
>  	sched->score = score ? score : &sched->_score;
>  	sched->dev = dev;
> +	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
> +		drm_sched_policy_default : sched_policy;
>  	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
>  		drm_sched_rq_init(sched, &sched->sched_rq[i]);
>  
> diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
> index 38e092ea41e6..dec89c5b8cb1 100644
> --- a/drivers/gpu/drm/v3d/v3d_sched.c
> +++ b/drivers/gpu/drm/v3d/v3d_sched.c
> @@ -391,7 +391,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_bin_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_bin", v3d->drm.dev);
> +			     NULL, "v3d_bin", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		return ret;
>  
> @@ -399,7 +400,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_render_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_render", v3d->drm.dev);
> +			     NULL, "v3d_render", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		goto fail;
>  
> @@ -407,7 +409,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_tfu_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_tfu", v3d->drm.dev);
> +			     NULL, "v3d_tfu", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		goto fail;
>  
> @@ -416,7 +419,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  				     &v3d_csd_sched_ops, NULL,
>  				     hw_jobs_limit, job_hang_limit,
>  				     msecs_to_jiffies(hang_limit_ms), NULL,
> -				     NULL, "v3d_csd", v3d->drm.dev);
> +				     NULL, "v3d_csd", DRM_SCHED_POLICY_UNSET,
> +				     v3d->drm.dev);
>  		if (ret)
>  			goto fail;
>  
> @@ -424,7 +428,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  				     &v3d_cache_clean_sched_ops, NULL,
>  				     hw_jobs_limit, job_hang_limit,
>  				     msecs_to_jiffies(hang_limit_ms), NULL,
> -				     NULL, "v3d_cache_clean", v3d->drm.dev);
> +				     NULL, "v3d_cache_clean",
> +				     DRM_SCHED_POLICY_UNSET, v3d->drm.dev);
>  		if (ret)
>  			goto fail;
>  	}
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 211bd3cdabdc..320f0a720486 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -72,11 +72,15 @@ enum drm_sched_priority {
>  	DRM_SCHED_PRIORITY_UNSET = -2
>  };
>  
> -/* Used to chose between FIFO and RR jobs scheduling */
> -extern int drm_sched_policy;
> -
> -#define DRM_SCHED_POLICY_RR    0
> -#define DRM_SCHED_POLICY_FIFO  1
> +/* Used to chose default scheduling policy*/
> +extern int default_drm_sched_policy;
> +
> +enum drm_sched_policy {
> +	DRM_SCHED_POLICY_UNSET,
> +	DRM_SCHED_POLICY_RR,
> +	DRM_SCHED_POLICY_FIFO,
> +	DRM_SCHED_POLICY_COUNT,
> +};
>  
>  /**
>   * struct drm_sched_entity - A wrapper around a job queue (typically
> @@ -489,6 +493,7 @@ struct drm_sched_backend_ops {
>   *              guilty and it will no longer be considered for scheduling.
>   * @score: score to help loadbalancer pick a idle sched
>   * @_score: score used when the driver doesn't provide one
> + * @sched_policy: Schedule policy for scheduler
>   * @ready: marks if the underlying HW is ready to work
>   * @free_guilty: A hit to time out handler to free the guilty job.
>   * @pause_submit: pause queuing of @work_submit on @submit_wq
> @@ -515,6 +520,7 @@ struct drm_gpu_scheduler {
>  	int				hang_limit;
>  	atomic_t                        *score;
>  	atomic_t                        _score;
> +	enum drm_sched_policy		sched_policy;
>  	bool				ready;
>  	bool				free_guilty;
>  	bool				pause_submit;
> @@ -527,7 +533,9 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		   struct workqueue_struct *submit_wq,
>  		   uint32_t hw_submission, unsigned hang_limit,
>  		   long timeout, struct workqueue_struct *timeout_wq,
> -		   atomic_t *score, const char *name, struct device *dev);
> +		   atomic_t *score, const char *name,
> +		   enum drm_sched_policy sched_policy,
> +		   struct device *dev);
>  
>  void drm_sched_fini(struct drm_gpu_scheduler *sched);
>  int drm_sched_job_init(struct drm_sched_job *job,

Re: [PATCH v5 1/7] drm/sched: Add drm_sched_wqueue_* helpers

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> Add scheduler wqueue ready, stop, and start helpers to hide the
> implementation details of the scheduler from the drivers.
> 
> v2:
>   - s/sched_wqueue/sched_wqueue (Luben)
>   - Remove the extra white line after the return-statement (Luben)
>   - update drm_sched_wqueue_ready comment (Luben)
> 
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> Cc: Luben Tuikov <luben.tuikov@amd.com>

Cc comes before S-O-B, but I can fix this when applying it, so don't worry about
this patch anymore. I'll also add Link: and so on, but this is all automated for
me so don't worry about it.

Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
-- 
Regards,
Luben

> ---
>  .../drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c   |  2 +-
>  drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c   | 15 +++----
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c    | 12 +++---
>  drivers/gpu/drm/msm/adreno/adreno_device.c    |  6 ++-
>  drivers/gpu/drm/scheduler/sched_main.c        | 39 ++++++++++++++++++-
>  include/drm/gpu_scheduler.h                   |  3 ++
>  6 files changed, 59 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c
> index 625db444df1c..10d56979fe3b 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_arcturus.c
> @@ -290,7 +290,7 @@ static int suspend_resume_compute_scheduler(struct amdgpu_device *adev, bool sus
>  	for (i = 0; i < adev->gfx.num_compute_rings; i++) {
>  		struct amdgpu_ring *ring = &adev->gfx.compute_ring[i];
>  
> -		if (!(ring && ring->sched.thread))
> +		if (!(ring && drm_sched_wqueue_ready(&ring->sched)))
>  			continue;
>  
>  		/* stop secheduler and drain ring. */
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
> index a4faea4fa0b5..a4c0bb358db7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
> @@ -1659,9 +1659,9 @@ static int amdgpu_debugfs_test_ib_show(struct seq_file *m, void *unused)
>  	for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
>  		struct amdgpu_ring *ring = adev->rings[i];
>  
> -		if (!ring || !ring->sched.thread)
> +		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
>  			continue;
> -		kthread_park(ring->sched.thread);
> +		drm_sched_wqueue_stop(&ring->sched);
>  	}
>  
>  	seq_puts(m, "run ib test:\n");
> @@ -1675,9 +1675,9 @@ static int amdgpu_debugfs_test_ib_show(struct seq_file *m, void *unused)
>  	for (i = 0; i < AMDGPU_MAX_RINGS; i++) {
>  		struct amdgpu_ring *ring = adev->rings[i];
>  
> -		if (!ring || !ring->sched.thread)
> +		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
>  			continue;
> -		kthread_unpark(ring->sched.thread);
> +		drm_sched_wqueue_start(&ring->sched);
>  	}
>  
>  	up_write(&adev->reset_domain->sem);
> @@ -1897,7 +1897,8 @@ static int amdgpu_debugfs_ib_preempt(void *data, u64 val)
>  
>  	ring = adev->rings[val];
>  
> -	if (!ring || !ring->funcs->preempt_ib || !ring->sched.thread)
> +	if (!ring || !ring->funcs->preempt_ib ||
> +	    !drm_sched_wqueue_ready(&ring->sched))
>  		return -EINVAL;
>  
>  	/* the last preemption failed */
> @@ -1915,7 +1916,7 @@ static int amdgpu_debugfs_ib_preempt(void *data, u64 val)
>  		goto pro_end;
>  
>  	/* stop the scheduler */
> -	kthread_park(ring->sched.thread);
> +	drm_sched_wqueue_stop(&ring->sched);
>  
>  	/* preempt the IB */
>  	r = amdgpu_ring_preempt_ib(ring);
> @@ -1949,7 +1950,7 @@ static int amdgpu_debugfs_ib_preempt(void *data, u64 val)
>  
>  failure:
>  	/* restart the scheduler */
> -	kthread_unpark(ring->sched.thread);
> +	drm_sched_wqueue_start(&ring->sched);
>  
>  	up_read(&adev->reset_domain->sem);
>  
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 2b8356699f23..b1aafe815f28 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -4588,7 +4588,7 @@ bool amdgpu_device_has_job_running(struct amdgpu_device *adev)
>  	for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
>  		struct amdgpu_ring *ring = adev->rings[i];
>  
> -		if (!ring || !ring->sched.thread)
> +		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
>  			continue;
>  
>  		spin_lock(&ring->sched.job_list_lock);
> @@ -4727,7 +4727,7 @@ int amdgpu_device_pre_asic_reset(struct amdgpu_device *adev,
>  	for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
>  		struct amdgpu_ring *ring = adev->rings[i];
>  
> -		if (!ring || !ring->sched.thread)
> +		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
>  			continue;
>  
>  		/* Clear job fence from fence drv to avoid force_completion
> @@ -5266,7 +5266,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
>  		for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
>  			struct amdgpu_ring *ring = tmp_adev->rings[i];
>  
> -			if (!ring || !ring->sched.thread)
> +			if (!ring || !drm_sched_wqueue_ready(&ring->sched))
>  				continue;
>  
>  			drm_sched_stop(&ring->sched, job ? &job->base : NULL);
> @@ -5341,7 +5341,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
>  		for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
>  			struct amdgpu_ring *ring = tmp_adev->rings[i];
>  
> -			if (!ring || !ring->sched.thread)
> +			if (!ring || !drm_sched_wqueue_ready(&ring->sched))
>  				continue;
>  
>  			drm_sched_start(&ring->sched, true);
> @@ -5667,7 +5667,7 @@ pci_ers_result_t amdgpu_pci_error_detected(struct pci_dev *pdev, pci_channel_sta
>  		for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
>  			struct amdgpu_ring *ring = adev->rings[i];
>  
> -			if (!ring || !ring->sched.thread)
> +			if (!ring || !drm_sched_wqueue_ready(&ring->sched))
>  				continue;
>  
>  			drm_sched_stop(&ring->sched, NULL);
> @@ -5795,7 +5795,7 @@ void amdgpu_pci_resume(struct pci_dev *pdev)
>  	for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
>  		struct amdgpu_ring *ring = adev->rings[i];
>  
> -		if (!ring || !ring->sched.thread)
> +		if (!ring || !drm_sched_wqueue_ready(&ring->sched))
>  			continue;
>  
>  		drm_sched_start(&ring->sched, true);
> diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm/msm/adreno/adreno_device.c
> index fa527935ffd4..8fa9ce3746b6 100644
> --- a/drivers/gpu/drm/msm/adreno/adreno_device.c
> +++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
> @@ -809,7 +809,8 @@ static void suspend_scheduler(struct msm_gpu *gpu)
>  	 */
>  	for (i = 0; i < gpu->nr_rings; i++) {
>  		struct drm_gpu_scheduler *sched = &gpu->rb[i]->sched;
> -		kthread_park(sched->thread);
> +
> +		drm_sched_wqueue_stop(sched);
>  	}
>  }
>  
> @@ -819,7 +820,8 @@ static void resume_scheduler(struct msm_gpu *gpu)
>  
>  	for (i = 0; i < gpu->nr_rings; i++) {
>  		struct drm_gpu_scheduler *sched = &gpu->rb[i]->sched;
> -		kthread_unpark(sched->thread);
> +
> +		drm_sched_wqueue_start(sched);
>  	}
>  }
>  
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 5a3a622fc672..6f2f7dd4ba0a 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -439,7 +439,7 @@ void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad)
>  {
>  	struct drm_sched_job *s_job, *tmp;
>  
> -	kthread_park(sched->thread);
> +	drm_sched_wqueue_stop(sched);
>  
>  	/*
>  	 * Reinsert back the bad job here - now it's safe as
> @@ -552,7 +552,7 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
>  		spin_unlock(&sched->job_list_lock);
>  	}
>  
> -	kthread_unpark(sched->thread);
> +	drm_sched_wqueue_start(sched);
>  }
>  EXPORT_SYMBOL(drm_sched_start);
>  
> @@ -1206,3 +1206,38 @@ void drm_sched_increase_karma(struct drm_sched_job *bad)
>  	}
>  }
>  EXPORT_SYMBOL(drm_sched_increase_karma);
> +
> +/**
> + * drm_sched_wqueue_ready - Is the scheduler ready for submission
> + *
> + * @sched: scheduler instance
> + *
> + * Returns true if submission is ready
> + */
> +bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched)
> +{
> +	return !!sched->thread;
> +}
> +EXPORT_SYMBOL(drm_sched_wqueue_ready);
> +
> +/**
> + * drm_sched_wqueue_stop - stop scheduler submission
> + *
> + * @sched: scheduler instance
> + */
> +void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched)
> +{
> +	kthread_park(sched->thread);
> +}
> +EXPORT_SYMBOL(drm_sched_wqueue_stop);
> +
> +/**
> + * drm_sched_wqueue_start - start scheduler submission
> + *
> + * @sched: scheduler instance
> + */
> +void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched)
> +{
> +	kthread_unpark(sched->thread);
> +}
> +EXPORT_SYMBOL(drm_sched_wqueue_start);
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index f9544d9b670d..38578fe74573 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -550,6 +550,9 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
>  
>  void drm_sched_job_cleanup(struct drm_sched_job *job);
>  void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched);
> +bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched);
> +void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched);
> +void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched);
>  void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad);
>  void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery);
>  void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched);

Re: [PATCH v5 2/7] drm/sched: Convert drm scheduler to use a work queue rather than kthread

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> In Xe, the new Intel GPU driver, a choice has made to have a 1 to 1
> mapping between a drm_gpu_scheduler and drm_sched_entity. At first this
> seems a bit odd but let us explain the reasoning below.
> 
> 1. In Xe the submission order from multiple drm_sched_entity is not
> guaranteed to be the same completion even if targeting the same hardware
> engine. This is because in Xe we have a firmware scheduler, the GuC,
> which allowed to reorder, timeslice, and preempt submissions. If a using
> shared drm_gpu_scheduler across multiple drm_sched_entity, the TDR falls
> apart as the TDR expects submission order == completion order. Using a
> dedicated drm_gpu_scheduler per drm_sched_entity solve this problem.
> 
> 2. In Xe submissions are done via programming a ring buffer (circular
> buffer), a drm_gpu_scheduler provides a limit on number of jobs, if the
> limit of number jobs is set to RING_SIZE / MAX_SIZE_PER_JOB we get flow
> control on the ring for free.
> 
> A problem with this design is currently a drm_gpu_scheduler uses a
> kthread for submission / job cleanup. This doesn't scale if a large
> number of drm_gpu_scheduler are used. To work around the scaling issue,
> use a worker rather than kthread for submission / job cleanup.
> 
> v2:
>   - (Rob Clark) Fix msm build
>   - Pass in run work queue
> v3:
>   - (Boris) don't have loop in worker
> v4:
>   - (Tvrtko) break out submit ready, stop, start helpers into own patch
> v5:
>   - (Boris) default to ordered work queue
> v6:
>   - (Luben / checkpatch) fix alignment in msm_ringbuffer.c
>   - (Luben) s/drm_sched_submit_queue/drm_sched_wqueue_enqueue
>   - (Luben) Update comment for drm_sched_wqueue_enqueue
>   - (Luben) Positive check for submit_wq in drm_sched_init
>   - (Luben) s/alloc_submit_wq/own_submit_wq
> 
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>

Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |   2 +-
>  drivers/gpu/drm/etnaviv/etnaviv_sched.c    |   2 +-
>  drivers/gpu/drm/lima/lima_sched.c          |   2 +-
>  drivers/gpu/drm/msm/msm_ringbuffer.c       |   7 +-
>  drivers/gpu/drm/nouveau/nouveau_sched.c    |   2 +-
>  drivers/gpu/drm/panfrost/panfrost_job.c    |   2 +-
>  drivers/gpu/drm/scheduler/sched_main.c     | 118 ++++++++++-----------
>  drivers/gpu/drm/v3d/v3d_sched.c            |  10 +-
>  include/drm/gpu_scheduler.h                |  14 ++-
>  9 files changed, 82 insertions(+), 77 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index b1aafe815f28..b54c4d771104 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -2279,7 +2279,7 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
>  			break;
>  		}
>  
> -		r = drm_sched_init(&ring->sched, &amdgpu_sched_ops,
> +		r = drm_sched_init(&ring->sched, &amdgpu_sched_ops, NULL,
>  				   ring->num_hw_submission, 0,
>  				   timeout, adev->reset_domain->wq,
>  				   ring->sched_score, ring->name,
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> index 345fec6cb1a4..618a804ddc34 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> @@ -134,7 +134,7 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
>  {
>  	int ret;
>  
> -	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops,
> +	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops, NULL,
>  			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
>  			     msecs_to_jiffies(500), NULL, NULL,
>  			     dev_name(gpu->dev), gpu->dev);
> diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
> index ffd91a5ee299..8d858aed0e56 100644
> --- a/drivers/gpu/drm/lima/lima_sched.c
> +++ b/drivers/gpu/drm/lima/lima_sched.c
> @@ -488,7 +488,7 @@ int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
>  
>  	INIT_WORK(&pipe->recover_work, lima_sched_recover_work);
>  
> -	return drm_sched_init(&pipe->base, &lima_sched_ops, 1,
> +	return drm_sched_init(&pipe->base, &lima_sched_ops, NULL, 1,
>  			      lima_job_hang_limit,
>  			      msecs_to_jiffies(timeout), NULL,
>  			      NULL, name, pipe->ldev->dev);
> diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
> index 40c0bc35a44c..1097f8e93d6b 100644
> --- a/drivers/gpu/drm/msm/msm_ringbuffer.c
> +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
> @@ -94,9 +94,10 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
>  	 /* currently managing hangcheck ourselves: */
>  	sched_timeout = MAX_SCHEDULE_TIMEOUT;
>  
> -	ret = drm_sched_init(&ring->sched, &msm_sched_ops,
> -			num_hw_submissions, 0, sched_timeout,
> -			NULL, NULL, to_msm_bo(ring->bo)->name, gpu->dev->dev);
> +	ret = drm_sched_init(&ring->sched, &msm_sched_ops, NULL,
> +			     num_hw_submissions, 0, sched_timeout,
> +			     NULL, NULL, to_msm_bo(ring->bo)->name,
> +			     gpu->dev->dev);
>  	if (ret) {
>  		goto fail;
>  	}
> diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
> index 3b7ea5221226..4c959dec42b3 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_sched.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
> @@ -435,7 +435,7 @@ int nouveau_sched_init(struct nouveau_drm *drm)
>  	if (!drm->sched_wq)
>  		return -ENOMEM;
>  
> -	return drm_sched_init(sched, &nouveau_sched_ops,
> +	return drm_sched_init(sched, &nouveau_sched_ops, NULL,
>  			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
>  			      NULL, NULL, "nouveau_sched", drm->dev->dev);
>  }
> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
> index fb16de2d0420..934b7b930c76 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_job.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> @@ -852,7 +852,7 @@ int panfrost_job_init(struct panfrost_device *pfdev)
>  		js->queue[j].fence_context = dma_fence_context_alloc(1);
>  
>  		ret = drm_sched_init(&js->queue[j].sched,
> -				     &panfrost_sched_ops,
> +				     &panfrost_sched_ops, NULL,
>  				     nentries, 0,
>  				     msecs_to_jiffies(JOB_TIMEOUT_MS),
>  				     pfdev->reset.wq,
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 6f2f7dd4ba0a..8b1d52cff1e9 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -48,7 +48,6 @@
>   * through the jobs entity pointer.
>   */
>  
> -#include <linux/kthread.h>
>  #include <linux/wait.h>
>  #include <linux/sched.h>
>  #include <linux/completion.h>
> @@ -256,6 +255,16 @@ drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
>  	return rb ? rb_entry(rb, struct drm_sched_entity, rb_tree_node) : NULL;
>  }
>  
> +/**
> + * drm_sched_wqueue_enqueue - enqueue scheduler submission
> + * @sched: scheduler instance
> + */
> +static void drm_sched_wqueue_enqueue(struct drm_gpu_scheduler *sched)
> +{
> +	if (!READ_ONCE(sched->pause_submit))
> +		queue_work(sched->submit_wq, &sched->work_submit);
> +}
> +
>  /**
>   * drm_sched_job_done - complete a job
>   * @s_job: pointer to the job which is done
> @@ -275,7 +284,7 @@ static void drm_sched_job_done(struct drm_sched_job *s_job, int result)
>  	dma_fence_get(&s_fence->finished);
>  	drm_sched_fence_finished(s_fence, result);
>  	dma_fence_put(&s_fence->finished);
> -	wake_up_interruptible(&sched->wake_up_worker);
> +	drm_sched_wqueue_enqueue(sched);
>  }
>  
>  /**
> @@ -868,7 +877,7 @@ static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
>  void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched)
>  {
>  	if (drm_sched_can_queue(sched))
> -		wake_up_interruptible(&sched->wake_up_worker);
> +		drm_sched_wqueue_enqueue(sched);
>  }
>  
>  /**
> @@ -978,61 +987,42 @@ drm_sched_pick_best(struct drm_gpu_scheduler **sched_list,
>  }
>  EXPORT_SYMBOL(drm_sched_pick_best);
>  
> -/**
> - * drm_sched_blocked - check if the scheduler is blocked
> - *
> - * @sched: scheduler instance
> - *
> - * Returns true if blocked, otherwise false.
> - */
> -static bool drm_sched_blocked(struct drm_gpu_scheduler *sched)
> -{
> -	if (kthread_should_park()) {
> -		kthread_parkme();
> -		return true;
> -	}
> -
> -	return false;
> -}
> -
>  /**
>   * drm_sched_main - main scheduler thread
>   *
>   * @param: scheduler instance
> - *
> - * Returns 0.
>   */
> -static int drm_sched_main(void *param)
> +static void drm_sched_main(struct work_struct *w)
>  {
> -	struct drm_gpu_scheduler *sched = (struct drm_gpu_scheduler *)param;
> +	struct drm_gpu_scheduler *sched =
> +		container_of(w, struct drm_gpu_scheduler, work_submit);
> +	struct drm_sched_entity *entity;
> +	struct drm_sched_job *cleanup_job;
>  	int r;
>  
> -	sched_set_fifo_low(current);
> +	if (READ_ONCE(sched->pause_submit))
> +		return;
>  
> -	while (!kthread_should_stop()) {
> -		struct drm_sched_entity *entity = NULL;
> -		struct drm_sched_fence *s_fence;
> -		struct drm_sched_job *sched_job;
> -		struct dma_fence *fence;
> -		struct drm_sched_job *cleanup_job = NULL;
> +	cleanup_job = drm_sched_get_cleanup_job(sched);
> +	entity = drm_sched_select_entity(sched);
>  
> -		wait_event_interruptible(sched->wake_up_worker,
> -					 (cleanup_job = drm_sched_get_cleanup_job(sched)) ||
> -					 (!drm_sched_blocked(sched) &&
> -					  (entity = drm_sched_select_entity(sched))) ||
> -					 kthread_should_stop());
> +	if (!entity && !cleanup_job)
> +		return;	/* No more work */
>  
> -		if (cleanup_job)
> -			sched->ops->free_job(cleanup_job);
> +	if (cleanup_job)
> +		sched->ops->free_job(cleanup_job);
>  
> -		if (!entity)
> -			continue;
> +	if (entity) {
> +		struct dma_fence *fence;
> +		struct drm_sched_fence *s_fence;
> +		struct drm_sched_job *sched_job;
>  
>  		sched_job = drm_sched_entity_pop_job(entity);
> -
>  		if (!sched_job) {
>  			complete_all(&entity->entity_idle);
> -			continue;
> +			if (!cleanup_job)
> +				return;	/* No more work */
> +			goto again;
>  		}
>  
>  		s_fence = sched_job->s_fence;
> @@ -1063,7 +1053,9 @@ static int drm_sched_main(void *param)
>  
>  		wake_up(&sched->job_scheduled);
>  	}
> -	return 0;
> +
> +again:
> +	drm_sched_wqueue_enqueue(sched);
>  }
>  
>  /**
> @@ -1071,6 +1063,8 @@ static int drm_sched_main(void *param)
>   *
>   * @sched: scheduler instance
>   * @ops: backend operations for this scheduler
> + * @submit_wq: workqueue to use for submission. If NULL, an ordered wq is
> + *	       allocated and used
>   * @hw_submission: number of hw submissions that can be in flight
>   * @hang_limit: number of times to allow a job to hang before dropping it
>   * @timeout: timeout value in jiffies for the scheduler
> @@ -1084,14 +1078,25 @@ static int drm_sched_main(void *param)
>   */
>  int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		   const struct drm_sched_backend_ops *ops,
> +		   struct workqueue_struct *submit_wq,
>  		   unsigned hw_submission, unsigned hang_limit,
>  		   long timeout, struct workqueue_struct *timeout_wq,
>  		   atomic_t *score, const char *name, struct device *dev)
>  {
> -	int i, ret;
> +	int i;
>  	sched->ops = ops;
>  	sched->hw_submission_limit = hw_submission;
>  	sched->name = name;
> +	if (submit_wq) {
> +		sched->submit_wq = submit_wq;
> +		sched->own_submit_wq = false;
> +	} else {
> +		sched->submit_wq = alloc_ordered_workqueue(name, 0);
> +		if (!sched->submit_wq)
> +			return -ENOMEM;
> +
> +		sched->own_submit_wq = true;
> +	}
>  	sched->timeout = timeout;
>  	sched->timeout_wq = timeout_wq ? : system_wq;
>  	sched->hang_limit = hang_limit;
> @@ -1100,23 +1105,15 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
>  		drm_sched_rq_init(sched, &sched->sched_rq[i]);
>  
> -	init_waitqueue_head(&sched->wake_up_worker);
>  	init_waitqueue_head(&sched->job_scheduled);
>  	INIT_LIST_HEAD(&sched->pending_list);
>  	spin_lock_init(&sched->job_list_lock);
>  	atomic_set(&sched->hw_rq_count, 0);
>  	INIT_DELAYED_WORK(&sched->work_tdr, drm_sched_job_timedout);
> +	INIT_WORK(&sched->work_submit, drm_sched_main);
>  	atomic_set(&sched->_score, 0);
>  	atomic64_set(&sched->job_id_count, 0);
> -
> -	/* Each scheduler will run on a seperate kernel thread */
> -	sched->thread = kthread_run(drm_sched_main, sched, sched->name);
> -	if (IS_ERR(sched->thread)) {
> -		ret = PTR_ERR(sched->thread);
> -		sched->thread = NULL;
> -		DRM_DEV_ERROR(sched->dev, "Failed to create scheduler for %s.\n", name);
> -		return ret;
> -	}
> +	sched->pause_submit = false;
>  
>  	sched->ready = true;
>  	return 0;
> @@ -1135,8 +1132,7 @@ void drm_sched_fini(struct drm_gpu_scheduler *sched)
>  	struct drm_sched_entity *s_entity;
>  	int i;
>  
> -	if (sched->thread)
> -		kthread_stop(sched->thread);
> +	drm_sched_wqueue_stop(sched);
>  
>  	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
>  		struct drm_sched_rq *rq = &sched->sched_rq[i];
> @@ -1159,6 +1155,8 @@ void drm_sched_fini(struct drm_gpu_scheduler *sched)
>  	/* Confirm no work left behind accessing device structures */
>  	cancel_delayed_work_sync(&sched->work_tdr);
>  
> +	if (sched->own_submit_wq)
> +		destroy_workqueue(sched->submit_wq);
>  	sched->ready = false;
>  }
>  EXPORT_SYMBOL(drm_sched_fini);
> @@ -1216,7 +1214,7 @@ EXPORT_SYMBOL(drm_sched_increase_karma);
>   */
>  bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched)
>  {
> -	return !!sched->thread;
> +	return sched->ready;
>  }
>  EXPORT_SYMBOL(drm_sched_wqueue_ready);
>  
> @@ -1227,7 +1225,8 @@ EXPORT_SYMBOL(drm_sched_wqueue_ready);
>   */
>  void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched)
>  {
> -	kthread_park(sched->thread);
> +	WRITE_ONCE(sched->pause_submit, true);
> +	cancel_work_sync(&sched->work_submit);
>  }
>  EXPORT_SYMBOL(drm_sched_wqueue_stop);
>  
> @@ -1238,6 +1237,7 @@ EXPORT_SYMBOL(drm_sched_wqueue_stop);
>   */
>  void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched)
>  {
> -	kthread_unpark(sched->thread);
> +	WRITE_ONCE(sched->pause_submit, false);
> +	queue_work(sched->submit_wq, &sched->work_submit);
>  }
>  EXPORT_SYMBOL(drm_sched_wqueue_start);
> diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
> index 06238e6d7f5c..38e092ea41e6 100644
> --- a/drivers/gpu/drm/v3d/v3d_sched.c
> +++ b/drivers/gpu/drm/v3d/v3d_sched.c
> @@ -388,7 +388,7 @@ v3d_sched_init(struct v3d_dev *v3d)
>  	int ret;
>  
>  	ret = drm_sched_init(&v3d->queue[V3D_BIN].sched,
> -			     &v3d_bin_sched_ops,
> +			     &v3d_bin_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
>  			     NULL, "v3d_bin", v3d->drm.dev);
> @@ -396,7 +396,7 @@ v3d_sched_init(struct v3d_dev *v3d)
>  		return ret;
>  
>  	ret = drm_sched_init(&v3d->queue[V3D_RENDER].sched,
> -			     &v3d_render_sched_ops,
> +			     &v3d_render_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
>  			     NULL, "v3d_render", v3d->drm.dev);
> @@ -404,7 +404,7 @@ v3d_sched_init(struct v3d_dev *v3d)
>  		goto fail;
>  
>  	ret = drm_sched_init(&v3d->queue[V3D_TFU].sched,
> -			     &v3d_tfu_sched_ops,
> +			     &v3d_tfu_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
>  			     NULL, "v3d_tfu", v3d->drm.dev);
> @@ -413,7 +413,7 @@ v3d_sched_init(struct v3d_dev *v3d)
>  
>  	if (v3d_has_csd(v3d)) {
>  		ret = drm_sched_init(&v3d->queue[V3D_CSD].sched,
> -				     &v3d_csd_sched_ops,
> +				     &v3d_csd_sched_ops, NULL,
>  				     hw_jobs_limit, job_hang_limit,
>  				     msecs_to_jiffies(hang_limit_ms), NULL,
>  				     NULL, "v3d_csd", v3d->drm.dev);
> @@ -421,7 +421,7 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			goto fail;
>  
>  		ret = drm_sched_init(&v3d->queue[V3D_CACHE_CLEAN].sched,
> -				     &v3d_cache_clean_sched_ops,
> +				     &v3d_cache_clean_sched_ops, NULL,
>  				     hw_jobs_limit, job_hang_limit,
>  				     msecs_to_jiffies(hang_limit_ms), NULL,
>  				     NULL, "v3d_cache_clean", v3d->drm.dev);
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 38578fe74573..211bd3cdabdc 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -473,17 +473,16 @@ struct drm_sched_backend_ops {
>   * @timeout: the time after which a job is removed from the scheduler.
>   * @name: name of the ring for which this scheduler is being used.
>   * @sched_rq: priority wise array of run queues.
> - * @wake_up_worker: the wait queue on which the scheduler sleeps until a job
> - *                  is ready to be scheduled.
>   * @job_scheduled: once @drm_sched_entity_do_release is called the scheduler
>   *                 waits on this wait queue until all the scheduled jobs are
>   *                 finished.
>   * @hw_rq_count: the number of jobs currently in the hardware queue.
>   * @job_id_count: used to assign unique id to the each job.
> + * @submit_wq: workqueue used to queue @work_submit
>   * @timeout_wq: workqueue used to queue @work_tdr
> + * @work_submit: schedules jobs and cleans up entities
>   * @work_tdr: schedules a delayed call to @drm_sched_job_timedout after the
>   *            timeout interval is over.
> - * @thread: the kthread on which the scheduler which run.
>   * @pending_list: the list of jobs which are currently in the job queue.
>   * @job_list_lock: lock to protect the pending_list.
>   * @hang_limit: once the hangs by a job crosses this limit then it is marked
> @@ -492,6 +491,8 @@ struct drm_sched_backend_ops {
>   * @_score: score used when the driver doesn't provide one
>   * @ready: marks if the underlying HW is ready to work
>   * @free_guilty: A hit to time out handler to free the guilty job.
> + * @pause_submit: pause queuing of @work_submit on @submit_wq
> + * @own_submit_wq: scheduler owns allocation of @submit_wq
>   * @dev: system &struct device
>   *
>   * One scheduler is implemented for each hardware ring.
> @@ -502,13 +503,13 @@ struct drm_gpu_scheduler {
>  	long				timeout;
>  	const char			*name;
>  	struct drm_sched_rq		sched_rq[DRM_SCHED_PRIORITY_COUNT];
> -	wait_queue_head_t		wake_up_worker;
>  	wait_queue_head_t		job_scheduled;
>  	atomic_t			hw_rq_count;
>  	atomic64_t			job_id_count;
> +	struct workqueue_struct		*submit_wq;
>  	struct workqueue_struct		*timeout_wq;
> +	struct work_struct		work_submit;
>  	struct delayed_work		work_tdr;
> -	struct task_struct		*thread;
>  	struct list_head		pending_list;
>  	spinlock_t			job_list_lock;
>  	int				hang_limit;
> @@ -516,11 +517,14 @@ struct drm_gpu_scheduler {
>  	atomic_t                        _score;
>  	bool				ready;
>  	bool				free_guilty;
> +	bool				pause_submit;
> +	bool				own_submit_wq;
>  	struct device			*dev;
>  };
>  
>  int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		   const struct drm_sched_backend_ops *ops,
> +		   struct workqueue_struct *submit_wq,
>  		   uint32_t hw_submission, unsigned hang_limit,
>  		   long timeout, struct workqueue_struct *timeout_wq,
>  		   atomic_t *score, const char *name, struct device *dev);

-- 
Regards,
Luben

Re: [PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> Rather than a global modparam for scheduling policy, move the scheduling
> policy to scheduler so user can control each scheduler policy.
> 
> v2:
>   - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
>   - Only include policy in scheduler (Luben)
> v3:
>   - use a ternary operator as opposed to an if-control (Luben)
>   - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
>   - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
>   - Update commit message (Boris)
>   - Fix v3d build (CI)
>   - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
>   - Don't update modparam doc (Luben)
> v4:
>   - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)
> 
> Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>

Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  1 +
>  drivers/gpu/drm/etnaviv/etnaviv_sched.c    |  3 ++-
>  drivers/gpu/drm/lima/lima_sched.c          |  3 ++-
>  drivers/gpu/drm/msm/msm_ringbuffer.c       |  2 +-
>  drivers/gpu/drm/nouveau/nouveau_sched.c    |  3 ++-
>  drivers/gpu/drm/panfrost/panfrost_job.c    |  3 ++-
>  drivers/gpu/drm/scheduler/sched_entity.c   | 24 ++++++++++++++++++----
>  drivers/gpu/drm/scheduler/sched_main.c     | 19 ++++++++++++-----
>  drivers/gpu/drm/v3d/v3d_sched.c            | 15 +++++++++-----
>  include/drm/gpu_scheduler.h                | 20 ++++++++++++------
>  10 files changed, 68 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index b54c4d771104..e4e6f91450a4 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -2283,6 +2283,7 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
>  				   ring->num_hw_submission, 0,
>  				   timeout, adev->reset_domain->wq,
>  				   ring->sched_score, ring->name,
> +				   DRM_SCHED_POLICY_UNSET,
>  				   adev->dev);
>  		if (r) {
>  			DRM_ERROR("Failed to create scheduler on ring %s.\n",
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> index 618a804ddc34..15b0e2f1abe5 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> @@ -137,7 +137,8 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
>  	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops, NULL,
>  			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
>  			     msecs_to_jiffies(500), NULL, NULL,
> -			     dev_name(gpu->dev), gpu->dev);
> +			     dev_name(gpu->dev), DRM_SCHED_POLICY_UNSET,
> +			     gpu->dev);
>  	if (ret)
>  		return ret;
>  
> diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
> index 8d858aed0e56..50c2075228aa 100644
> --- a/drivers/gpu/drm/lima/lima_sched.c
> +++ b/drivers/gpu/drm/lima/lima_sched.c
> @@ -491,7 +491,8 @@ int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
>  	return drm_sched_init(&pipe->base, &lima_sched_ops, NULL, 1,
>  			      lima_job_hang_limit,
>  			      msecs_to_jiffies(timeout), NULL,
> -			      NULL, name, pipe->ldev->dev);
> +			      NULL, name, DRM_SCHED_POLICY_UNSET,
> +			      pipe->ldev->dev);
>  }
>  
>  void lima_sched_pipe_fini(struct lima_sched_pipe *pipe)
> diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
> index 1097f8e93d6b..173ad2f17c50 100644
> --- a/drivers/gpu/drm/msm/msm_ringbuffer.c
> +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
> @@ -97,7 +97,7 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
>  	ret = drm_sched_init(&ring->sched, &msm_sched_ops, NULL,
>  			     num_hw_submissions, 0, sched_timeout,
>  			     NULL, NULL, to_msm_bo(ring->bo)->name,
> -			     gpu->dev->dev);
> +			     DRM_SCHED_POLICY_UNSET, gpu->dev->dev);
>  	if (ret) {
>  		goto fail;
>  	}
> diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
> index 4c959dec42b3..c4e09d2e77f9 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_sched.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
> @@ -437,7 +437,8 @@ int nouveau_sched_init(struct nouveau_drm *drm)
>  
>  	return drm_sched_init(sched, &nouveau_sched_ops, NULL,
>  			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
> -			      NULL, NULL, "nouveau_sched", drm->dev->dev);
> +			      NULL, NULL, "nouveau_sched",
> +			      DRM_SCHED_POLICY_UNSET, drm->dev->dev);
>  }
>  
>  void nouveau_sched_fini(struct nouveau_drm *drm)
> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
> index 934b7b930c76..95330ff402ba 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_job.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> @@ -856,7 +856,8 @@ int panfrost_job_init(struct panfrost_device *pfdev)
>  				     nentries, 0,
>  				     msecs_to_jiffies(JOB_TIMEOUT_MS),
>  				     pfdev->reset.wq,
> -				     NULL, "pan_js", pfdev->dev);
> +				     NULL, "pan_js", DRM_SCHED_POLICY_UNSET,
> +				     pfdev->dev);
>  		if (ret) {
>  			dev_err(pfdev->dev, "Failed to create scheduler: %d.", ret);
>  			goto err_sched;
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index a42763e1429d..cf42e2265d64 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -33,6 +33,20 @@
>  #define to_drm_sched_job(sched_job)		\
>  		container_of((sched_job), struct drm_sched_job, queue_node)
>  
> +static bool drm_sched_policy_mismatch(struct drm_gpu_scheduler **sched_list,
> +				      unsigned int num_sched_list)
> +{
> +	enum drm_sched_policy sched_policy = sched_list[0]->sched_policy;
> +	unsigned int i;
> +
> +	/* All schedule policies must match */
> +	for (i = 1; i < num_sched_list; ++i)
> +		if (sched_policy != sched_list[i]->sched_policy)
> +			return true;
> +
> +	return false;
> +}
> +
>  /**
>   * drm_sched_entity_init - Init a context entity used by scheduler when
>   * submit to HW ring.
> @@ -62,7 +76,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>  			  unsigned int num_sched_list,
>  			  atomic_t *guilty)
>  {
> -	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])))
> +	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])) ||
> +	    drm_sched_policy_mismatch(sched_list, num_sched_list))
>  		return -EINVAL;
>  
>  	memset(entity, 0, sizeof(struct drm_sched_entity));
> @@ -486,7 +501,7 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>  	 * Update the entity's location in the min heap according to
>  	 * the timestamp of the next job, if any.
>  	 */
> -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) {
> +	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
>  		struct drm_sched_job *next;
>  
>  		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
> @@ -558,7 +573,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
>  void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  {
>  	struct drm_sched_entity *entity = sched_job->entity;
> -	bool first;
> +	bool first, fifo = entity->rq->sched->sched_policy ==
> +		DRM_SCHED_POLICY_FIFO;
>  	ktime_t submit_ts;
>  
>  	trace_drm_sched_job(sched_job, entity);
> @@ -587,7 +603,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  		drm_sched_rq_add_entity(entity->rq, entity);
>  		spin_unlock(&entity->rq_lock);
>  
> -		if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> +		if (fifo)
>  			drm_sched_rq_update_fifo(entity, submit_ts);
>  
>  		drm_sched_wakeup_if_can_queue(entity->rq->sched);
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 8b1d52cff1e9..150e5330f0fa 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -66,14 +66,14 @@
>  #define to_drm_sched_job(sched_job)		\
>  		container_of((sched_job), struct drm_sched_job, queue_node)
>  
> -int drm_sched_policy = DRM_SCHED_POLICY_FIFO;
> +int drm_sched_policy_default = DRM_SCHED_POLICY_FIFO;
>  
>  /**
>   * DOC: sched_policy (int)
>   * Used to override default entities scheduling policy in a run queue.
>   */
>  MODULE_PARM_DESC(sched_policy, "Specify the scheduling policy for entities on a run-queue, " __stringify(DRM_SCHED_POLICY_RR) " = Round Robin, " __stringify(DRM_SCHED_POLICY_FIFO) " = FIFO (default).");
> -module_param_named(sched_policy, drm_sched_policy, int, 0444);
> +module_param_named(sched_policy, drm_sched_policy_default, int, 0444);
>  
>  static __always_inline bool drm_sched_entity_compare_before(struct rb_node *a,
>  							    const struct rb_node *b)
> @@ -177,7 +177,7 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
>  	if (rq->current_entity == entity)
>  		rq->current_entity = NULL;
>  
> -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> +	if (rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO)
>  		drm_sched_rq_remove_fifo_locked(entity);
>  
>  	spin_unlock(&rq->lock);
> @@ -898,7 +898,7 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
>  
>  	/* Kernel run queue has higher priority than normal run queue*/
>  	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> -		entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
> +		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
>  			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i]) :
>  			drm_sched_rq_select_entity_rr(&sched->sched_rq[i]);
>  		if (entity)
> @@ -1072,6 +1072,7 @@ static void drm_sched_main(struct work_struct *w)
>   *		used
>   * @score: optional score atomic shared with other schedulers
>   * @name: name used for debugging
> + * @sched_policy: schedule policy
>   * @dev: target &struct device
>   *
>   * Return 0 on success, otherwise error code.
> @@ -1081,9 +1082,15 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		   struct workqueue_struct *submit_wq,
>  		   unsigned hw_submission, unsigned hang_limit,
>  		   long timeout, struct workqueue_struct *timeout_wq,
> -		   atomic_t *score, const char *name, struct device *dev)
> +		   atomic_t *score, const char *name,
> +		   enum drm_sched_policy sched_policy,
> +		   struct device *dev)
>  {
>  	int i;
> +
> +	if (sched_policy >= DRM_SCHED_POLICY_COUNT)
> +		return -EINVAL;
> +
>  	sched->ops = ops;
>  	sched->hw_submission_limit = hw_submission;
>  	sched->name = name;
> @@ -1102,6 +1109,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  	sched->hang_limit = hang_limit;
>  	sched->score = score ? score : &sched->_score;
>  	sched->dev = dev;
> +	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
> +		drm_sched_policy_default : sched_policy;
>  	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
>  		drm_sched_rq_init(sched, &sched->sched_rq[i]);
>  
> diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
> index 38e092ea41e6..dec89c5b8cb1 100644
> --- a/drivers/gpu/drm/v3d/v3d_sched.c
> +++ b/drivers/gpu/drm/v3d/v3d_sched.c
> @@ -391,7 +391,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_bin_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_bin", v3d->drm.dev);
> +			     NULL, "v3d_bin", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		return ret;
>  
> @@ -399,7 +400,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_render_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_render", v3d->drm.dev);
> +			     NULL, "v3d_render", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		goto fail;
>  
> @@ -407,7 +409,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  			     &v3d_tfu_sched_ops, NULL,
>  			     hw_jobs_limit, job_hang_limit,
>  			     msecs_to_jiffies(hang_limit_ms), NULL,
> -			     NULL, "v3d_tfu", v3d->drm.dev);
> +			     NULL, "v3d_tfu", DRM_SCHED_POLICY_UNSET,
> +			     v3d->drm.dev);
>  	if (ret)
>  		goto fail;
>  
> @@ -416,7 +419,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  				     &v3d_csd_sched_ops, NULL,
>  				     hw_jobs_limit, job_hang_limit,
>  				     msecs_to_jiffies(hang_limit_ms), NULL,
> -				     NULL, "v3d_csd", v3d->drm.dev);
> +				     NULL, "v3d_csd", DRM_SCHED_POLICY_UNSET,
> +				     v3d->drm.dev);
>  		if (ret)
>  			goto fail;
>  
> @@ -424,7 +428,8 @@ v3d_sched_init(struct v3d_dev *v3d)
>  				     &v3d_cache_clean_sched_ops, NULL,
>  				     hw_jobs_limit, job_hang_limit,
>  				     msecs_to_jiffies(hang_limit_ms), NULL,
> -				     NULL, "v3d_cache_clean", v3d->drm.dev);
> +				     NULL, "v3d_cache_clean",
> +				     DRM_SCHED_POLICY_UNSET, v3d->drm.dev);
>  		if (ret)
>  			goto fail;
>  	}
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 211bd3cdabdc..320f0a720486 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -72,11 +72,15 @@ enum drm_sched_priority {
>  	DRM_SCHED_PRIORITY_UNSET = -2
>  };
>  
> -/* Used to chose between FIFO and RR jobs scheduling */
> -extern int drm_sched_policy;
> -
> -#define DRM_SCHED_POLICY_RR    0
> -#define DRM_SCHED_POLICY_FIFO  1
> +/* Used to chose default scheduling policy*/
> +extern int default_drm_sched_policy;
> +
> +enum drm_sched_policy {
> +	DRM_SCHED_POLICY_UNSET,
> +	DRM_SCHED_POLICY_RR,
> +	DRM_SCHED_POLICY_FIFO,
> +	DRM_SCHED_POLICY_COUNT,
> +};
>  
>  /**
>   * struct drm_sched_entity - A wrapper around a job queue (typically
> @@ -489,6 +493,7 @@ struct drm_sched_backend_ops {
>   *              guilty and it will no longer be considered for scheduling.
>   * @score: score to help loadbalancer pick a idle sched
>   * @_score: score used when the driver doesn't provide one
> + * @sched_policy: Schedule policy for scheduler
>   * @ready: marks if the underlying HW is ready to work
>   * @free_guilty: A hit to time out handler to free the guilty job.
>   * @pause_submit: pause queuing of @work_submit on @submit_wq
> @@ -515,6 +520,7 @@ struct drm_gpu_scheduler {
>  	int				hang_limit;
>  	atomic_t                        *score;
>  	atomic_t                        _score;
> +	enum drm_sched_policy		sched_policy;
>  	bool				ready;
>  	bool				free_guilty;
>  	bool				pause_submit;
> @@ -527,7 +533,9 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		   struct workqueue_struct *submit_wq,
>  		   uint32_t hw_submission, unsigned hang_limit,
>  		   long timeout, struct workqueue_struct *timeout_wq,
> -		   atomic_t *score, const char *name, struct device *dev);
> +		   atomic_t *score, const char *name,
> +		   enum drm_sched_policy sched_policy,
> +		   struct device *dev);
>  
>  void drm_sched_fini(struct drm_gpu_scheduler *sched);
>  int drm_sched_job_init(struct drm_sched_job *job,

-- 
Regards,
Luben

Re: [PATCH v5 4/7] drm/sched: Add DRM_SCHED_POLICY_SINGLE_ENTITY scheduling policy

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> DRM_SCHED_POLICY_SINGLE_ENTITY creates a 1 to 1 relationship between
> scheduler and entity. No priorities or run queue used in this mode.
> Intended for devices with firmware schedulers.
> 
> v2:
>   - Drop sched / rq union (Luben)
> v3:
>   - Don't pick entity if stopped in drm_sched_select_entity (Danilo)
> v4:
>   - Rework if statement in drm_sched_entity_init (Luben)
>   - Update comment for drm_sched_entity_to_scheduler (Luben)
>   - Reword a few things in DOC comment (Luben)
>   - Do not check sched policy in for statement (Luben)
> 
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> ---
>  drivers/gpu/drm/scheduler/sched_entity.c | 70 ++++++++++++++-----
>  drivers/gpu/drm/scheduler/sched_fence.c  |  2 +-
>  drivers/gpu/drm/scheduler/sched_main.c   | 86 ++++++++++++++++++------
>  include/drm/gpu_scheduler.h              |  8 +++
>  4 files changed, 131 insertions(+), 35 deletions(-)
> 
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index cf42e2265d64..1ef3883764f9 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -83,6 +83,7 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>  	memset(entity, 0, sizeof(struct drm_sched_entity));
>  	INIT_LIST_HEAD(&entity->list);
>  	entity->rq = NULL;
> +	entity->single_sched = NULL;
>  	entity->guilty = guilty;
>  	entity->num_sched_list = num_sched_list;
>  	entity->priority = priority;
> @@ -90,8 +91,18 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>  	RCU_INIT_POINTER(entity->last_scheduled, NULL);
>  	RB_CLEAR_NODE(&entity->rb_tree_node);
>  
> -	if(num_sched_list)
> -		entity->rq = &sched_list[0]->sched_rq[entity->priority];
> +

^ This adds an extra blank line and scripts/checkpatch.pl rejects it.

> +	if (num_sched_list) {
> +		if (sched_list[0]->sched_policy !=
> +		    DRM_SCHED_POLICY_SINGLE_ENTITY) {
> +			entity->rq = &sched_list[0]->sched_rq[entity->priority];
> +		} else if (num_sched_list == 1 && !sched_list[0]->single_entity) {
> +			sched_list[0]->single_entity = entity;
> +			entity->single_sched = sched_list[0];
> +		} else {
> +			return -EINVAL;
> +		}
> +	}
>  
>  	init_completion(&entity->entity_idle);
>  
> @@ -124,7 +135,8 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
>  				    struct drm_gpu_scheduler **sched_list,
>  				    unsigned int num_sched_list)
>  {
> -	WARN_ON(!num_sched_list || !sched_list);
> +	WARN_ON(!num_sched_list || !sched_list ||
> +		!!entity->single_sched);
>  
>  	entity->sched_list = sched_list;
>  	entity->num_sched_list = num_sched_list;
> @@ -231,13 +243,15 @@ static void drm_sched_entity_kill(struct drm_sched_entity *entity)
>  {
>  	struct drm_sched_job *job;
>  	struct dma_fence *prev;
> +	bool single_entity = !!entity->single_sched;
>  
> -	if (!entity->rq)
> +	if (!entity->rq && !single_entity)
>  		return;
>  
>  	spin_lock(&entity->rq_lock);
>  	entity->stopped = true;
> -	drm_sched_rq_remove_entity(entity->rq, entity);
> +	if (!single_entity)
> +		drm_sched_rq_remove_entity(entity->rq, entity);
>  	spin_unlock(&entity->rq_lock);
>  
>  	/* Make sure this entity is not used by the scheduler at the moment */
> @@ -259,6 +273,20 @@ static void drm_sched_entity_kill(struct drm_sched_entity *entity)
>  	dma_fence_put(prev);
>  }
>  
> +/**
> + * drm_sched_entity_to_scheduler - Schedule entity to GPU scheduler
> + * @entity: scheduler entity
> + *
> + * Returns GPU scheduler for the entity
> + */
> +struct drm_gpu_scheduler *
> +drm_sched_entity_to_scheduler(struct drm_sched_entity *entity)
> +{
> +	bool single_entity = !!entity->single_sched;
> +
> +	return single_entity ? entity->single_sched : entity->rq->sched;
> +}
> +
>  /**
>   * drm_sched_entity_flush - Flush a context entity
>   *
> @@ -276,11 +304,12 @@ long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout)
>  	struct drm_gpu_scheduler *sched;
>  	struct task_struct *last_user;
>  	long ret = timeout;
> +	bool single_entity = !!entity->single_sched;
>  
> -	if (!entity->rq)
> +	if (!entity->rq && !single_entity)
>  		return 0;
>  
> -	sched = entity->rq->sched;
> +	sched = drm_sched_entity_to_scheduler(entity);
>  	/**
>  	 * The client will not queue more IBs during this fini, consume existing
>  	 * queued IBs or discard them on SIGKILL
> @@ -373,7 +402,7 @@ static void drm_sched_entity_wakeup(struct dma_fence *f,
>  		container_of(cb, struct drm_sched_entity, cb);
>  
>  	drm_sched_entity_clear_dep(f, cb);
> -	drm_sched_wakeup_if_can_queue(entity->rq->sched);
> +	drm_sched_wakeup_if_can_queue(drm_sched_entity_to_scheduler(entity));
>  }
>  
>  /**
> @@ -387,6 +416,8 @@ static void drm_sched_entity_wakeup(struct dma_fence *f,
>  void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
>  				   enum drm_sched_priority priority)
>  {
> +	WARN_ON(!!entity->single_sched);
> +
>  	spin_lock(&entity->rq_lock);
>  	entity->priority = priority;
>  	spin_unlock(&entity->rq_lock);
> @@ -399,7 +430,7 @@ EXPORT_SYMBOL(drm_sched_entity_set_priority);
>   */
>  static bool drm_sched_entity_add_dependency_cb(struct drm_sched_entity *entity)
>  {
> -	struct drm_gpu_scheduler *sched = entity->rq->sched;
> +	struct drm_gpu_scheduler *sched = drm_sched_entity_to_scheduler(entity);
>  	struct dma_fence *fence = entity->dependency;
>  	struct drm_sched_fence *s_fence;
>  
> @@ -501,7 +532,8 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>  	 * Update the entity's location in the min heap according to
>  	 * the timestamp of the next job, if any.
>  	 */
> -	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
> +	if (drm_sched_entity_to_scheduler(entity)->sched_policy ==
> +	    DRM_SCHED_POLICY_FIFO) {
>  		struct drm_sched_job *next;
>  
>  		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
> @@ -524,6 +556,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
>  	struct drm_gpu_scheduler *sched;
>  	struct drm_sched_rq *rq;
>  
> +	WARN_ON(!!entity->single_sched);
> +
>  	/* single possible engine and already selected */
>  	if (!entity->sched_list)
>  		return;
> @@ -573,12 +607,13 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
>  void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  {
>  	struct drm_sched_entity *entity = sched_job->entity;
> -	bool first, fifo = entity->rq->sched->sched_policy ==
> -		DRM_SCHED_POLICY_FIFO;
> +	bool single_entity = !!entity->single_sched;
> +	bool first;
>  	ktime_t submit_ts;
>  
>  	trace_drm_sched_job(sched_job, entity);
> -	atomic_inc(entity->rq->sched->score);
> +	if (!single_entity)
> +		atomic_inc(entity->rq->sched->score);
>  	WRITE_ONCE(entity->last_user, current->group_leader);
>  
>  	/*
> @@ -591,6 +626,10 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  
>  	/* first job wakes up scheduler */
>  	if (first) {
> +		struct drm_gpu_scheduler *sched =
> +			drm_sched_entity_to_scheduler(entity);
> +		bool fifo = sched->sched_policy == DRM_SCHED_POLICY_FIFO;
> +
>  		/* Add the entity to the run queue */
>  		spin_lock(&entity->rq_lock);
>  		if (entity->stopped) {
> @@ -600,13 +639,14 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>  			return;
>  		}
>  
> -		drm_sched_rq_add_entity(entity->rq, entity);
> +		if (!single_entity)
> +			drm_sched_rq_add_entity(entity->rq, entity);
>  		spin_unlock(&entity->rq_lock);
>  
>  		if (fifo)
>  			drm_sched_rq_update_fifo(entity, submit_ts);
>  
> -		drm_sched_wakeup_if_can_queue(entity->rq->sched);
> +		drm_sched_wakeup_if_can_queue(sched);
>  	}
>  }
>  EXPORT_SYMBOL(drm_sched_entity_push_job);
> diff --git a/drivers/gpu/drm/scheduler/sched_fence.c b/drivers/gpu/drm/scheduler/sched_fence.c
> index 06cedfe4b486..f6b926f5e188 100644
> --- a/drivers/gpu/drm/scheduler/sched_fence.c
> +++ b/drivers/gpu/drm/scheduler/sched_fence.c
> @@ -225,7 +225,7 @@ void drm_sched_fence_init(struct drm_sched_fence *fence,
>  {
>  	unsigned seq;
>  
> -	fence->sched = entity->rq->sched;
> +	fence->sched = drm_sched_entity_to_scheduler(entity);
>  	seq = atomic_inc_return(&entity->fence_seq);
>  	dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled,
>  		       &fence->lock, entity->fence_context, seq);
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 150e5330f0fa..7dbb3392124d 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -32,7 +32,8 @@
>   * backend operations to the scheduler like submitting a job to hardware run queue,
>   * returning the dependencies of a job etc.
>   *
> - * The organisation of the scheduler is the following:
> + * For scheduling policies DRM_SCHED_POLICY_RR and DRM_SCHED_POLICY_FIFO, the
> + * scheduler organization is:
>   *
>   * 1. Each hw run queue has one scheduler
>   * 2. Each scheduler has multiple run queues with different priorities
> @@ -43,7 +44,24 @@
>   *
>   * The jobs in a entity are always scheduled in the order that they were pushed.
>   *
> - * Note that once a job was taken from the entities queue and pushed to the
> + * For DRM_SCHED_POLICY_SINGLE_ENTITY, the organization of the scheduler is:
> + *
> + * 1. One to one relationship between scheduler and entity
> + * 2. No priorities implemented per scheduler (single job queue)
> + * 3. No run queues in scheduler rather jobs are directly dequeued from entity
> + * 4. The entity maintains a queue of jobs that will be scheduled to the
> + * hardware
> + *
> + * The jobs in a entity are always scheduled in the order that they were pushed
> + * regardless of scheduling policy. Single-entity scheduling is essentially a
> + * FIFO for jobs.
> + *
> + * A policy of DRM_SCHED_POLICY_RR or DRM_SCHED_POLICY_FIFO is expected to be
> + * used when the kernel-mode driver is scheduling directly to the hardware while
> + * a scheduling policy of DRM_SCHED_POLICY_SINGLE_ENTITY is expected to be used
> + * when there is a firmware scheduler.
> + *
> + * Note that once a job is taken from the entities queue and pushed to the
>   * hardware, i.e. the pending queue, the entity must not be referenced anymore
>   * through the jobs entity pointer.
>   */
> @@ -96,6 +114,8 @@ static inline void drm_sched_rq_remove_fifo_locked(struct drm_sched_entity *enti
>  
>  void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
>  {
> +	WARN_ON(!!entity->single_sched);
> +
>  	/*
>  	 * Both locks need to be grabbed, one to protect from entity->rq change
>  	 * for entity from within concurrent drm_sched_entity_select_rq and the
> @@ -126,6 +146,8 @@ void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
>  static void drm_sched_rq_init(struct drm_gpu_scheduler *sched,
>  			      struct drm_sched_rq *rq)
>  {
> +	WARN_ON(sched->sched_policy == DRM_SCHED_POLICY_SINGLE_ENTITY);
> +
>  	spin_lock_init(&rq->lock);
>  	INIT_LIST_HEAD(&rq->entities);
>  	rq->rb_tree_root = RB_ROOT_CACHED;
> @@ -144,6 +166,8 @@ static void drm_sched_rq_init(struct drm_gpu_scheduler *sched,
>  void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
>  			     struct drm_sched_entity *entity)
>  {
> +	WARN_ON(!!entity->single_sched);
> +
>  	if (!list_empty(&entity->list))
>  		return;
>  
> @@ -166,6 +190,8 @@ void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
>  void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
>  				struct drm_sched_entity *entity)
>  {
> +	WARN_ON(!!entity->single_sched);
> +
>  	if (list_empty(&entity->list))
>  		return;
>  
> @@ -641,7 +667,7 @@ int drm_sched_job_init(struct drm_sched_job *job,
>  		       struct drm_sched_entity *entity,
>  		       void *owner)
>  {
> -	if (!entity->rq)
> +	if (!entity->rq && !entity->single_sched)
>  		return -ENOENT;
>  
>  	job->entity = entity;
> @@ -674,13 +700,16 @@ void drm_sched_job_arm(struct drm_sched_job *job)
>  {
>  	struct drm_gpu_scheduler *sched;
>  	struct drm_sched_entity *entity = job->entity;
> +	bool single_entity = !!entity->single_sched;
>  
>  	BUG_ON(!entity);
> -	drm_sched_entity_select_rq(entity);
> -	sched = entity->rq->sched;
> +	if (!single_entity)
> +		drm_sched_entity_select_rq(entity);
> +	sched = drm_sched_entity_to_scheduler(entity);
>  
>  	job->sched = sched;
> -	job->s_priority = entity->rq - sched->sched_rq;
> +	if (!single_entity)
> +		job->s_priority = entity->rq - sched->sched_rq;
>  	job->id = atomic64_inc_return(&sched->job_id_count);
>  
>  	drm_sched_fence_init(job->s_fence, job->entity);
> @@ -896,6 +925,14 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
>  	if (!drm_sched_can_queue(sched))
>  		return NULL;
>  
> +	if (sched->single_entity) {
> +		if (!READ_ONCE(sched->single_entity->stopped) &&
> +		    drm_sched_entity_is_ready(sched->single_entity))
> +			return sched->single_entity;
> +
> +		return NULL;
> +	}
> +
>  	/* Kernel run queue has higher priority than normal run queue*/
>  	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
>  		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
> @@ -1092,6 +1129,7 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  		return -EINVAL;
>  
>  	sched->ops = ops;
> +	sched->single_entity = NULL;
>  	sched->hw_submission_limit = hw_submission;
>  	sched->name = name;
>  	if (submit_wq) {
> @@ -1111,8 +1149,10 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  	sched->dev = dev;
>  	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
>  		drm_sched_policy_default : sched_policy;
> -	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
> -		drm_sched_rq_init(sched, &sched->sched_rq[i]);
> +	if (sched_policy != DRM_SCHED_POLICY_SINGLE_ENTITY) {
> +		for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
> +			drm_sched_rq_init(sched, &sched->sched_rq[i]);
> +	}
>  
>  	init_waitqueue_head(&sched->job_scheduled);
>  	INIT_LIST_HEAD(&sched->pending_list);
> @@ -1143,19 +1183,25 @@ void drm_sched_fini(struct drm_gpu_scheduler *sched)
>  
>  	drm_sched_wqueue_stop(sched);
>  
> -	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> -		struct drm_sched_rq *rq = &sched->sched_rq[i];
> +	if (sched->single_entity) {
> +		spin_lock(&sched->single_entity->rq_lock);
> +		sched->single_entity->stopped = true;
> +		spin_unlock(&sched->single_entity->rq_lock);
> +	} else if (sched->sched_policy != DRM_SCHED_POLICY_SINGLE_ENTITY) {
> +		for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> +			struct drm_sched_rq *rq = &sched->sched_rq[i];
>  
> -		spin_lock(&rq->lock);
> -		list_for_each_entry(s_entity, &rq->entities, list)
> -			/*
> -			 * Prevents reinsertion and marks job_queue as idle,
> -			 * it will removed from rq in drm_sched_entity_fini
> -			 * eventually
> -			 */
> -			s_entity->stopped = true;
> -		spin_unlock(&rq->lock);
> +			spin_lock(&rq->lock);
> +			list_for_each_entry(s_entity, &rq->entities, list)
> +				/*
> +				 * Prevents reinsertion and marks job_queue as idle,
> +				 * it will removed from rq in drm_sched_entity_fini
> +				 * eventually
> +				 */
> +				s_entity->stopped = true;
> +			spin_unlock(&rq->lock);
>  
> +		}

^ Blank lines aren't necessary before a closing brace.

I've fixed both of these locally, and would like to try something before R-V-ing this patch.

>  	}
>  
>  	/* Wakeup everyone stuck in drm_sched_entity_flush for this scheduler */
> @@ -1186,6 +1232,8 @@ void drm_sched_increase_karma(struct drm_sched_job *bad)
>  	struct drm_sched_entity *entity;
>  	struct drm_gpu_scheduler *sched = bad->sched;
>  
> +	WARN_ON(sched->sched_policy == DRM_SCHED_POLICY_SINGLE_ENTITY);
> +
>  	/* don't change @bad's karma if it's from KERNEL RQ,
>  	 * because sometimes GPU hang would cause kernel jobs (like VM updating jobs)
>  	 * corrupt but keep in mind that kernel jobs always considered good.
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 320f0a720486..e67b53c3546b 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -79,6 +79,7 @@ enum drm_sched_policy {
>  	DRM_SCHED_POLICY_UNSET,
>  	DRM_SCHED_POLICY_RR,
>  	DRM_SCHED_POLICY_FIFO,
> +	DRM_SCHED_POLICY_SINGLE_ENTITY,
>  	DRM_SCHED_POLICY_COUNT,
>  };
>  
> @@ -112,6 +113,9 @@ struct drm_sched_entity {
>  	 */
>  	struct drm_sched_rq		*rq;
>  
> +	/** @single_sched: Single scheduler */
> +	struct drm_gpu_scheduler	*single_sched;
> +
>  	/**
>  	 * @sched_list:
>  	 *
> @@ -473,6 +477,7 @@ struct drm_sched_backend_ops {
>   * struct drm_gpu_scheduler - scheduler instance-specific data
>   *
>   * @ops: backend operations provided by the driver.
> + * @single_entity: Single entity for the scheduler
>   * @hw_submission_limit: the max size of the hardware queue.
>   * @timeout: the time after which a job is removed from the scheduler.
>   * @name: name of the ring for which this scheduler is being used.
> @@ -504,6 +509,7 @@ struct drm_sched_backend_ops {
>   */
>  struct drm_gpu_scheduler {
>  	const struct drm_sched_backend_ops	*ops;
> +	struct drm_sched_entity		*single_entity;
>  	uint32_t			hw_submission_limit;
>  	long				timeout;
>  	const char			*name;
> @@ -587,6 +593,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>  			  struct drm_gpu_scheduler **sched_list,
>  			  unsigned int num_sched_list,
>  			  atomic_t *guilty);
> +struct drm_gpu_scheduler *
> +drm_sched_entity_to_scheduler(struct drm_sched_entity *entity);
>  long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout);
>  void drm_sched_entity_fini(struct drm_sched_entity *entity);
>  void drm_sched_entity_destroy(struct drm_sched_entity *entity);

-- 
Regards,
Luben

Re: [PATCH v5 5/7] drm/sched: Split free_job into own work item

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> Rather than call free_job and run_job in same work item have a dedicated
> work item for each. This aligns with the design and intended use of work
> queues.
> 
> v2:
>    - Test for DMA_FENCE_FLAG_TIMESTAMP_BIT before setting
>      timestamp in free_job() work item (Danilo)
> v3:
>   - Drop forward dec of drm_sched_select_entity (Boris)
>   - Return in drm_sched_run_job_work if entity NULL (Boris)
> v4:
>   - Replace dequeue with peek and invert logic (Luben)
>   - Wrap to 100 lines (Luben)
>   - Update comments for *_queue / *_queue_if_ready functions (Luben)
> 
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>

I wasn't able to apply this patch on top of drm-misc-next at a48e2cc92835fa.

Create a branch off of a *clean* drm-misc-next and rebase/reapply/cherry-pick all
7 patches on top of that clean drm-misc-next branch. You should also run
scripts/checkpatch.pl --strict on all your patches, or integrate it into the precommit
hook, see githooks(5), so you don't have to run it manually.

Set format.useAutobase to whenAble somewhere in your Git configs (global/local),
or use --base=auto to git-format-patch when you format your patches before
git-send-email-ing them.

Repost your patches.

The base commit will be added to the bottom of the cover letter. It should
be an ancestor (or tip) of drm-misc-next (git branch --contains <base> --list etc.).
If it is not, your base tree wasn't clean, and you should redo this process.
-- 
Regards,
Luben

> ---
>  drivers/gpu/drm/scheduler/sched_main.c | 287 +++++++++++++++----------
>  include/drm/gpu_scheduler.h            |   8 +-
>  2 files changed, 178 insertions(+), 117 deletions(-)
> 
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 7dbb3392124d..cf4c23db7547 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -213,11 +213,12 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
>   * drm_sched_rq_select_entity_rr - Select an entity which could provide a job to run
>   *
>   * @rq: scheduler run queue to check.
> + * @peek: Just find, don't set to current.
>   *
>   * Try to find a ready entity, returns NULL if none found.
>   */
>  static struct drm_sched_entity *
> -drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq)
> +drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq, bool peek)
>  {
>  	struct drm_sched_entity *entity;
>  
> @@ -227,8 +228,10 @@ drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq)
>  	if (entity) {
>  		list_for_each_entry_continue(entity, &rq->entities, list) {
>  			if (drm_sched_entity_is_ready(entity)) {
> -				rq->current_entity = entity;
> -				reinit_completion(&entity->entity_idle);
> +				if (!peek) {
> +					rq->current_entity = entity;
> +					reinit_completion(&entity->entity_idle);
> +				}
>  				spin_unlock(&rq->lock);
>  				return entity;
>  			}
> @@ -238,8 +241,10 @@ drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq)
>  	list_for_each_entry(entity, &rq->entities, list) {
>  
>  		if (drm_sched_entity_is_ready(entity)) {
> -			rq->current_entity = entity;
> -			reinit_completion(&entity->entity_idle);
> +			if (!peek) {
> +				rq->current_entity = entity;
> +				reinit_completion(&entity->entity_idle);
> +			}
>  			spin_unlock(&rq->lock);
>  			return entity;
>  		}
> @@ -257,11 +262,12 @@ drm_sched_rq_select_entity_rr(struct drm_sched_rq *rq)
>   * drm_sched_rq_select_entity_fifo - Select an entity which provides a job to run
>   *
>   * @rq: scheduler run queue to check.
> + * @peek: Just find, don't set to current.
>   *
>   * Find oldest waiting ready entity, returns NULL if none found.
>   */
>  static struct drm_sched_entity *
> -drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
> +drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq, bool peek)
>  {
>  	struct rb_node *rb;
>  
> @@ -271,8 +277,10 @@ drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
>  
>  		entity = rb_entry(rb, struct drm_sched_entity, rb_tree_node);
>  		if (drm_sched_entity_is_ready(entity)) {
> -			rq->current_entity = entity;
> -			reinit_completion(&entity->entity_idle);
> +			if (!peek) {
> +				rq->current_entity = entity;
> +				reinit_completion(&entity->entity_idle);
> +			}
>  			break;
>  		}
>  	}
> @@ -282,13 +290,98 @@ drm_sched_rq_select_entity_fifo(struct drm_sched_rq *rq)
>  }
>  
>  /**
> - * drm_sched_wqueue_enqueue - enqueue scheduler submission
> + * drm_sched_run_job_queue - enqueue run-job work
> + * @sched: scheduler instance
> + */
> +static void drm_sched_run_job_queue(struct drm_gpu_scheduler *sched)
> +{
> +	if (!READ_ONCE(sched->pause_submit))
> +		queue_work(sched->submit_wq, &sched->work_run_job);
> +}
> +
> +/**
> + * drm_sched_can_queue -- Can we queue more to the hardware?
> + * @sched: scheduler instance
> + *
> + * Return true if we can push more jobs to the hw, otherwise false.
> + */
> +static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
> +{
> +	return atomic_read(&sched->hw_rq_count) <
> +		sched->hw_submission_limit;
> +}
> +
> +/**
> + * drm_sched_select_entity - Select next entity to process
> + *
> + * @sched: scheduler instance
> + * @peek: Just find, don't set to current.
> + *
> + * Returns the entity to process or NULL if none are found.
> + */
> +static struct drm_sched_entity *
> +drm_sched_select_entity(struct drm_gpu_scheduler *sched, bool peek)
> +{
> +	struct drm_sched_entity *entity;
> +	int i;
> +
> +	if (!drm_sched_can_queue(sched))
> +		return NULL;
> +
> +	if (sched->single_entity) {
> +		if (!READ_ONCE(sched->single_entity->stopped) &&
> +		    drm_sched_entity_is_ready(sched->single_entity))
> +			return sched->single_entity;
> +
> +		return NULL;
> +	}
> +
> +	/* Kernel run queue has higher priority than normal run queue*/
> +	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> +		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
> +			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i], peek) :
> +			drm_sched_rq_select_entity_rr(&sched->sched_rq[i], peek);
> +		if (entity)
> +			break;
> +	}
> +
> +	return entity;
> +}
> +
> +/**
> + * drm_sched_run_job_queue_if_ready - enqueue run-job work if ready
> + * @sched: scheduler instance
> + */
> +static void drm_sched_run_job_queue_if_ready(struct drm_gpu_scheduler *sched)
> +{
> +	if (drm_sched_select_entity(sched, false))
> +		drm_sched_run_job_queue(sched);
> +}
> +
> +/**
> + * drm_sched_free_job_queue - enqueue free-job work
>   * @sched: scheduler instance
>   */
> -static void drm_sched_wqueue_enqueue(struct drm_gpu_scheduler *sched)
> +static void drm_sched_free_job_queue(struct drm_gpu_scheduler *sched)
>  {
>  	if (!READ_ONCE(sched->pause_submit))
> -		queue_work(sched->submit_wq, &sched->work_submit);
> +		queue_work(sched->submit_wq, &sched->work_free_job);
> +}
> +
> +/**
> + * drm_sched_free_job_queue_if_ready - enqueue free-job work if ready
> + * @sched: scheduler instance
> + */
> +static void drm_sched_free_job_queue_if_ready(struct drm_gpu_scheduler *sched)
> +{
> +	struct drm_sched_job *job;
> +
> +	spin_lock(&sched->job_list_lock);
> +	job = list_first_entry_or_null(&sched->pending_list,
> +				       struct drm_sched_job, list);
> +	if (job && dma_fence_is_signaled(&job->s_fence->finished))
> +		drm_sched_free_job_queue(sched);
> +	spin_unlock(&sched->job_list_lock);
>  }
>  
>  /**
> @@ -310,7 +403,7 @@ static void drm_sched_job_done(struct drm_sched_job *s_job, int result)
>  	dma_fence_get(&s_fence->finished);
>  	drm_sched_fence_finished(s_fence, result);
>  	dma_fence_put(&s_fence->finished);
> -	drm_sched_wqueue_enqueue(sched);
> +	drm_sched_free_job_queue(sched);
>  }
>  
>  /**
> @@ -576,7 +669,7 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
>  				drm_sched_job_done(s_job, fence->error);
>  			else if (r)
>  				DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n",
> -					  r);
> +					      r);
>  		} else
>  			drm_sched_job_done(s_job, -ECANCELED);
>  	}
> @@ -885,18 +978,6 @@ void drm_sched_job_cleanup(struct drm_sched_job *job)
>  }
>  EXPORT_SYMBOL(drm_sched_job_cleanup);
>  
> -/**
> - * drm_sched_can_queue -- Can we queue more to the hardware?
> - * @sched: scheduler instance
> - *
> - * Return true if we can push more jobs to the hw, otherwise false.
> - */
> -static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
> -{
> -	return atomic_read(&sched->hw_rq_count) <
> -		sched->hw_submission_limit;
> -}
> -
>  /**
>   * drm_sched_wakeup_if_can_queue - Wake up the scheduler
>   * @sched: scheduler instance
> @@ -906,43 +987,7 @@ static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched)
>  void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched)
>  {
>  	if (drm_sched_can_queue(sched))
> -		drm_sched_wqueue_enqueue(sched);
> -}
> -
> -/**
> - * drm_sched_select_entity - Select next entity to process
> - *
> - * @sched: scheduler instance
> - *
> - * Returns the entity to process or NULL if none are found.
> - */
> -static struct drm_sched_entity *
> -drm_sched_select_entity(struct drm_gpu_scheduler *sched)
> -{
> -	struct drm_sched_entity *entity;
> -	int i;
> -
> -	if (!drm_sched_can_queue(sched))
> -		return NULL;
> -
> -	if (sched->single_entity) {
> -		if (!READ_ONCE(sched->single_entity->stopped) &&
> -		    drm_sched_entity_is_ready(sched->single_entity))
> -			return sched->single_entity;
> -
> -		return NULL;
> -	}
> -
> -	/* Kernel run queue has higher priority than normal run queue*/
> -	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> -		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
> -			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i]) :
> -			drm_sched_rq_select_entity_rr(&sched->sched_rq[i]);
> -		if (entity)
> -			break;
> -	}
> -
> -	return entity;
> +		drm_sched_run_job_queue(sched);
>  }
>  
>  /**
> @@ -974,8 +1019,10 @@ drm_sched_get_cleanup_job(struct drm_gpu_scheduler *sched)
>  						typeof(*next), list);
>  
>  		if (next) {
> -			next->s_fence->scheduled.timestamp =
> -				dma_fence_timestamp(&job->s_fence->finished);
> +			if (test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT,
> +				     &next->s_fence->scheduled.flags))
> +				next->s_fence->scheduled.timestamp =
> +					dma_fence_timestamp(&job->s_fence->finished);
>  			/* start TO timer for next job */
>  			drm_sched_start_timeout(sched);
>  		}
> @@ -1025,74 +1072,83 @@ drm_sched_pick_best(struct drm_gpu_scheduler **sched_list,
>  EXPORT_SYMBOL(drm_sched_pick_best);
>  
>  /**
> - * drm_sched_main - main scheduler thread
> + * drm_sched_free_job_work - worker to call free_job
>   *
> - * @param: scheduler instance
> + * @w: free job work
>   */
> -static void drm_sched_main(struct work_struct *w)
> +static void drm_sched_free_job_work(struct work_struct *w)
>  {
>  	struct drm_gpu_scheduler *sched =
> -		container_of(w, struct drm_gpu_scheduler, work_submit);
> -	struct drm_sched_entity *entity;
> +		container_of(w, struct drm_gpu_scheduler, work_free_job);
>  	struct drm_sched_job *cleanup_job;
> -	int r;
>  
>  	if (READ_ONCE(sched->pause_submit))
>  		return;
>  
>  	cleanup_job = drm_sched_get_cleanup_job(sched);
> -	entity = drm_sched_select_entity(sched);
> -
> -	if (!entity && !cleanup_job)
> -		return;	/* No more work */
> -
> -	if (cleanup_job)
> +	if (cleanup_job) {
>  		sched->ops->free_job(cleanup_job);
>  
> -	if (entity) {
> -		struct dma_fence *fence;
> -		struct drm_sched_fence *s_fence;
> -		struct drm_sched_job *sched_job;
> -
> -		sched_job = drm_sched_entity_pop_job(entity);
> -		if (!sched_job) {
> -			complete_all(&entity->entity_idle);
> -			if (!cleanup_job)
> -				return;	/* No more work */
> -			goto again;
> -		}
> +		drm_sched_free_job_queue_if_ready(sched);
> +		drm_sched_run_job_queue_if_ready(sched);
> +	}
> +}
>  
> -		s_fence = sched_job->s_fence;
> +/**
> + * drm_sched_run_job_work - worker to call run_job
> + *
> + * @w: run job work
> + */
> +static void drm_sched_run_job_work(struct work_struct *w)
> +{
> +	struct drm_gpu_scheduler *sched =
> +		container_of(w, struct drm_gpu_scheduler, work_run_job);
> +	struct drm_sched_entity *entity;
> +	struct dma_fence *fence;
> +	struct drm_sched_fence *s_fence;
> +	struct drm_sched_job *sched_job;
> +	int r;
>  
> -		atomic_inc(&sched->hw_rq_count);
> -		drm_sched_job_begin(sched_job);
> +	if (READ_ONCE(sched->pause_submit))
> +		return;
> +
> +	entity = drm_sched_select_entity(sched, true);
> +	if (!entity)
> +		return;
>  
> -		trace_drm_run_job(sched_job, entity);
> -		fence = sched->ops->run_job(sched_job);
> +	sched_job = drm_sched_entity_pop_job(entity);
> +	if (!sched_job) {
>  		complete_all(&entity->entity_idle);
> -		drm_sched_fence_scheduled(s_fence, fence);
> +		return;	/* No more work */
> +	}
>  
> -		if (!IS_ERR_OR_NULL(fence)) {
> -			/* Drop for original kref_init of the fence */
> -			dma_fence_put(fence);
> +	s_fence = sched_job->s_fence;
>  
> -			r = dma_fence_add_callback(fence, &sched_job->cb,
> -						   drm_sched_job_done_cb);
> -			if (r == -ENOENT)
> -				drm_sched_job_done(sched_job, fence->error);
> -			else if (r)
> -				DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n",
> -					  r);
> -		} else {
> -			drm_sched_job_done(sched_job, IS_ERR(fence) ?
> -					   PTR_ERR(fence) : 0);
> -		}
> +	atomic_inc(&sched->hw_rq_count);
> +	drm_sched_job_begin(sched_job);
>  
> -		wake_up(&sched->job_scheduled);
> +	trace_drm_run_job(sched_job, entity);
> +	fence = sched->ops->run_job(sched_job);
> +	complete_all(&entity->entity_idle);
> +	drm_sched_fence_scheduled(s_fence, fence);
> +
> +	if (!IS_ERR_OR_NULL(fence)) {
> +		/* Drop for original kref_init of the fence */
> +		dma_fence_put(fence);
> +
> +		r = dma_fence_add_callback(fence, &sched_job->cb,
> +					   drm_sched_job_done_cb);
> +		if (r == -ENOENT)
> +			drm_sched_job_done(sched_job, fence->error);
> +		else if (r)
> +			DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n", r);
> +	} else {
> +		drm_sched_job_done(sched_job, IS_ERR(fence) ?
> +				   PTR_ERR(fence) : 0);
>  	}
>  
> -again:
> -	drm_sched_wqueue_enqueue(sched);
> +	wake_up(&sched->job_scheduled);
> +	drm_sched_run_job_queue_if_ready(sched);
>  }
>  
>  /**
> @@ -1159,7 +1215,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>  	spin_lock_init(&sched->job_list_lock);
>  	atomic_set(&sched->hw_rq_count, 0);
>  	INIT_DELAYED_WORK(&sched->work_tdr, drm_sched_job_timedout);
> -	INIT_WORK(&sched->work_submit, drm_sched_main);
> +	INIT_WORK(&sched->work_run_job, drm_sched_run_job_work);
> +	INIT_WORK(&sched->work_free_job, drm_sched_free_job_work);
>  	atomic_set(&sched->_score, 0);
>  	atomic64_set(&sched->job_id_count, 0);
>  	sched->pause_submit = false;
> @@ -1283,7 +1340,8 @@ EXPORT_SYMBOL(drm_sched_wqueue_ready);
>  void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched)
>  {
>  	WRITE_ONCE(sched->pause_submit, true);
> -	cancel_work_sync(&sched->work_submit);
> +	cancel_work_sync(&sched->work_run_job);
> +	cancel_work_sync(&sched->work_free_job);
>  }
>  EXPORT_SYMBOL(drm_sched_wqueue_stop);
>  
> @@ -1295,6 +1353,7 @@ EXPORT_SYMBOL(drm_sched_wqueue_stop);
>  void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched)
>  {
>  	WRITE_ONCE(sched->pause_submit, false);
> -	queue_work(sched->submit_wq, &sched->work_submit);
> +	queue_work(sched->submit_wq, &sched->work_run_job);
> +	queue_work(sched->submit_wq, &sched->work_free_job);
>  }
>  EXPORT_SYMBOL(drm_sched_wqueue_start);
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index e67b53c3546b..625ffe040de3 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -487,9 +487,10 @@ struct drm_sched_backend_ops {
>   *                 finished.
>   * @hw_rq_count: the number of jobs currently in the hardware queue.
>   * @job_id_count: used to assign unique id to the each job.
> - * @submit_wq: workqueue used to queue @work_submit
> + * @submit_wq: workqueue used to queue @work_run_job and @work_free_job
>   * @timeout_wq: workqueue used to queue @work_tdr
> - * @work_submit: schedules jobs and cleans up entities
> + * @work_run_job: schedules jobs
> + * @work_free_job: cleans up jobs
>   * @work_tdr: schedules a delayed call to @drm_sched_job_timedout after the
>   *            timeout interval is over.
>   * @pending_list: the list of jobs which are currently in the job queue.
> @@ -519,7 +520,8 @@ struct drm_gpu_scheduler {
>  	atomic64_t			job_id_count;
>  	struct workqueue_struct		*submit_wq;
>  	struct workqueue_struct		*timeout_wq;
> -	struct work_struct		work_submit;
> +	struct work_struct		work_run_job;
> +	struct work_struct		work_free_job;
>  	struct delayed_work		work_tdr;
>  	struct list_head		pending_list;
>  	spinlock_t			job_list_lock;

Re: [PATCH v5 6/7] drm/sched: Add drm_sched_start_timeout_unlocked helper

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> Also add a lockdep assert to drm_sched_start_timeout.
> 
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>

I don't remember sending a Reviewed-by email to this patch.

I'll add the R-V to the commit when I apply and push this patch,
after replying with a R-V email.

Regards,
Luben

> ---
>  drivers/gpu/drm/scheduler/sched_main.c | 23 +++++++++++++----------
>  1 file changed, 13 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index cf4c23db7547..c4d5c3d265a8 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -427,11 +427,20 @@ static void drm_sched_job_done_cb(struct dma_fence *f, struct dma_fence_cb *cb)
>   */
>  static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
>  {
> +	lockdep_assert_held(&sched->job_list_lock);
> +
>  	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
>  	    !list_empty(&sched->pending_list))
>  		queue_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
>  }
>  
> +static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
> +{
> +	spin_lock(&sched->job_list_lock);
> +	drm_sched_start_timeout(sched);
> +	spin_unlock(&sched->job_list_lock);
> +}
> +
>  /**
>   * drm_sched_fault - immediately start timeout handler
>   *
> @@ -544,11 +553,8 @@ static void drm_sched_job_timedout(struct work_struct *work)
>  		spin_unlock(&sched->job_list_lock);
>  	}
>  
> -	if (status != DRM_GPU_SCHED_STAT_ENODEV) {
> -		spin_lock(&sched->job_list_lock);
> -		drm_sched_start_timeout(sched);
> -		spin_unlock(&sched->job_list_lock);
> -	}
> +	if (status != DRM_GPU_SCHED_STAT_ENODEV)
> +		drm_sched_start_timeout_unlocked(sched);
>  }
>  
>  /**
> @@ -674,11 +680,8 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
>  			drm_sched_job_done(s_job, -ECANCELED);
>  	}
>  
> -	if (full_recovery) {
> -		spin_lock(&sched->job_list_lock);
> -		drm_sched_start_timeout(sched);
> -		spin_unlock(&sched->job_list_lock);
> -	}
> +	if (full_recovery)
> +		drm_sched_start_timeout_unlocked(sched);
>  
>  	drm_sched_wqueue_start(sched);
>  }

Re: [PATCH v5 7/7] drm/sched: Add helper to queue TDR immediately for current and future jobs

[Luben Tuikov]

On 2023-10-11 19:58, Matthew Brost wrote:
> Add helper to queue TDR immediately for current and future jobs. This is
> used in Xe, a new Intel GPU driver, to trigger a TDR to cleanup a
> drm_scheduler that encounter errors.

I think the best (most optimal) thing to do is to remove the last sentence
mentioning Xe. It is irrelevant to this patch. This patch is functional
as is, and worth having it as is.

So it's best to have just:

	Add a helper whereby a driver can invoke TDR immediately.

Also remove "for current and future jobs" from the title, as it is
implied by how TDR works. We want to say less.

	drm/sched: Add a helper to queue TDR immediately

These are only GPU scheduler changes, worth having on their own. The fact
that a new (future as of this moment) driver (Xe) would use them is irrelevant
at the moment. Other drivers (new, current?) would most likely end up using the changes
of these patches, and these changes go in on their own merit.

Regards,
Luben

> 
> v2:
>  - Drop timeout args, rename function, use mod delayed work (Luben)
> v3:
>  - s/XE/Xe (Luben)
>  - present tense in commit message (Luben)
>  - Adjust comment for drm_sched_tdr_queue_imm (Luben)
> 
> Cc: Luben Tuikov <luben.tuikov@amd.com>
> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> ---
>  drivers/gpu/drm/scheduler/sched_main.c | 18 +++++++++++++++++-
>  include/drm/gpu_scheduler.h            |  1 +
>  2 files changed, 18 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index c4d5c3d265a8..f2846745b067 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -431,7 +431,7 @@ static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
>  
>  	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
>  	    !list_empty(&sched->pending_list))
> -		queue_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
> +		mod_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
>  }
>  
>  static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
> @@ -441,6 +441,22 @@ static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
>  	spin_unlock(&sched->job_list_lock);
>  }
>  
> +/**
> + * drm_sched_tdr_queue_imm: - immediately start job timeout handler
> + *
> + * @sched: scheduler for which the timeout handling should be started.
> + *
> + * Start timeout handling immediately for the named scheduler.
> + */
> +void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched)
> +{
> +	spin_lock(&sched->job_list_lock);
> +	sched->timeout = 0;
> +	drm_sched_start_timeout(sched);
> +	spin_unlock(&sched->job_list_lock);
> +}
> +EXPORT_SYMBOL(drm_sched_tdr_queue_imm);
> +
>  /**
>   * drm_sched_fault - immediately start timeout handler
>   *
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 625ffe040de3..998b32b8d212 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -568,6 +568,7 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
>  				    struct drm_gpu_scheduler **sched_list,
>                                     unsigned int num_sched_list);
>  
> +void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched);
>  void drm_sched_job_cleanup(struct drm_sched_job *job);
>  void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched);
>  bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched);

Re: [PATCH v5 5/7] drm/sched: Split free_job into own work item

[Luben Tuikov]

On 2023-10-13 22:49, Luben Tuikov wrote:
> On 2023-10-11 19:58, Matthew Brost wrote:
>> Rather than call free_job and run_job in same work item have a dedicated
>> work item for each. This aligns with the design and intended use of work
>> queues.
>>
>> v2:
>>    - Test for DMA_FENCE_FLAG_TIMESTAMP_BIT before setting
>>      timestamp in free_job() work item (Danilo)
>> v3:
>>   - Drop forward dec of drm_sched_select_entity (Boris)
>>   - Return in drm_sched_run_job_work if entity NULL (Boris)
>> v4:
>>   - Replace dequeue with peek and invert logic (Luben)
>>   - Wrap to 100 lines (Luben)
>>   - Update comments for *_queue / *_queue_if_ready functions (Luben)
>>
>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> 
> I wasn't able to apply this patch on top of drm-misc-next at a48e2cc92835fa.
> 
> Create a branch off of a *clean* drm-misc-next and rebase/reapply/cherry-pick all
> 7 patches on top of that clean drm-misc-next branch. You should also run
> scripts/checkpatch.pl --strict on all your patches, or integrate it into the precommit
> hook, see githooks(5), so you don't have to run it manually.
> 
> Set format.useAutobase to whenAble somewhere in your Git configs (global/local),
> or use --base=auto to git-format-patch when you format your patches before
> git-send-email-ing them.
> 
> Repost your patches.
> 
> The base commit will be added to the bottom of the cover letter. It should
> be an ancestor (or tip) of drm-misc-next (git branch --contains <base> --list etc.).
> If it is not, your base tree wasn't clean, and you should redo this process.

Poking around I found out that this patch set is based off of drm-misc-fixes.
Had the base been included, it would've made this easier.
-- 
Regards,
Luben

Re: [PATCH v5 6/7] drm/sched: Add drm_sched_start_timeout_unlocked helper

[Matthew Brost]

On Fri, Oct 13, 2023 at 10:52:22PM -0400, Luben Tuikov wrote:
> On 2023-10-11 19:58, Matthew Brost wrote:
> > Also add a lockdep assert to drm_sched_start_timeout.
> > 
> > Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> > Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
> 
> I don't remember sending a Reviewed-by email to this patch.
> 

I believe you did send a RB:
https://patchwork.freedesktop.org/patch/558222/?series=121745&rev=6

> I'll add the R-V to the commit when I apply and push this patch,
> after replying with a R-V email.
>

Is manually adding a RB ok if it is in the correct place like it is in this patch?

Matt

> Regards,
> Luben
> 
> > ---
> >  drivers/gpu/drm/scheduler/sched_main.c | 23 +++++++++++++----------
> >  1 file changed, 13 insertions(+), 10 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> > index cf4c23db7547..c4d5c3d265a8 100644
> > --- a/drivers/gpu/drm/scheduler/sched_main.c
> > +++ b/drivers/gpu/drm/scheduler/sched_main.c
> > @@ -427,11 +427,20 @@ static void drm_sched_job_done_cb(struct dma_fence *f, struct dma_fence_cb *cb)
> >   */
> >  static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
> >  {
> > +	lockdep_assert_held(&sched->job_list_lock);
> > +
> >  	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
> >  	    !list_empty(&sched->pending_list))
> >  		queue_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
> >  }
> >  
> > +static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
> > +{
> > +	spin_lock(&sched->job_list_lock);
> > +	drm_sched_start_timeout(sched);
> > +	spin_unlock(&sched->job_list_lock);
> > +}
> > +
> >  /**
> >   * drm_sched_fault - immediately start timeout handler
> >   *
> > @@ -544,11 +553,8 @@ static void drm_sched_job_timedout(struct work_struct *work)
> >  		spin_unlock(&sched->job_list_lock);
> >  	}
> >  
> > -	if (status != DRM_GPU_SCHED_STAT_ENODEV) {
> > -		spin_lock(&sched->job_list_lock);
> > -		drm_sched_start_timeout(sched);
> > -		spin_unlock(&sched->job_list_lock);
> > -	}
> > +	if (status != DRM_GPU_SCHED_STAT_ENODEV)
> > +		drm_sched_start_timeout_unlocked(sched);
> >  }
> >  
> >  /**
> > @@ -674,11 +680,8 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
> >  			drm_sched_job_done(s_job, -ECANCELED);
> >  	}
> >  
> > -	if (full_recovery) {
> > -		spin_lock(&sched->job_list_lock);
> > -		drm_sched_start_timeout(sched);
> > -		spin_unlock(&sched->job_list_lock);
> > -	}
> > +	if (full_recovery)
> > +		drm_sched_start_timeout_unlocked(sched);
> >  
> >  	drm_sched_wqueue_start(sched);
> >  }
> 

Re: [PATCH v5 4/7] drm/sched: Add DRM_SCHED_POLICY_SINGLE_ENTITY scheduling policy

[Matthew Brost]

On Fri, Oct 13, 2023 at 10:06:18PM -0400, Luben Tuikov wrote:
> On 2023-10-11 19:58, Matthew Brost wrote:
> > DRM_SCHED_POLICY_SINGLE_ENTITY creates a 1 to 1 relationship between
> > scheduler and entity. No priorities or run queue used in this mode.
> > Intended for devices with firmware schedulers.
> > 
> > v2:
> >   - Drop sched / rq union (Luben)
> > v3:
> >   - Don't pick entity if stopped in drm_sched_select_entity (Danilo)
> > v4:
> >   - Rework if statement in drm_sched_entity_init (Luben)
> >   - Update comment for drm_sched_entity_to_scheduler (Luben)
> >   - Reword a few things in DOC comment (Luben)
> >   - Do not check sched policy in for statement (Luben)
> > 
> > Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> > ---
> >  drivers/gpu/drm/scheduler/sched_entity.c | 70 ++++++++++++++-----
> >  drivers/gpu/drm/scheduler/sched_fence.c  |  2 +-
> >  drivers/gpu/drm/scheduler/sched_main.c   | 86 ++++++++++++++++++------
> >  include/drm/gpu_scheduler.h              |  8 +++
> >  4 files changed, 131 insertions(+), 35 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> > index cf42e2265d64..1ef3883764f9 100644
> > --- a/drivers/gpu/drm/scheduler/sched_entity.c
> > +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> > @@ -83,6 +83,7 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
> >  	memset(entity, 0, sizeof(struct drm_sched_entity));
> >  	INIT_LIST_HEAD(&entity->list);
> >  	entity->rq = NULL;
> > +	entity->single_sched = NULL;
> >  	entity->guilty = guilty;
> >  	entity->num_sched_list = num_sched_list;
> >  	entity->priority = priority;
> > @@ -90,8 +91,18 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
> >  	RCU_INIT_POINTER(entity->last_scheduled, NULL);
> >  	RB_CLEAR_NODE(&entity->rb_tree_node);
> >  
> > -	if(num_sched_list)
> > -		entity->rq = &sched_list[0]->sched_rq[entity->priority];
> > +
> 
> ^ This adds an extra blank line and scripts/checkpatch.pl rejects it.
> 

Agree this isn't correct, will fix.

Question - catch patch doesn't complain for me though. Wondering what I
am missing:

mbrost@lstrano-desk:drivers.gpu.i915.drm-intel$ ./scripts/checkpatch.pl drivers/gpu/drm/i915/0004-drm-sched-Add-DRM_SCHED_POLICY_SINGLE_ENTITY-schedul.patch
total: 0 errors, 0 warnings, 386 lines checked

drivers/gpu/drm/i915/0004-drm-sched-Add-DRM_SCHED_POLICY_SINGLE_ENTITY-schedul.patch has no obvious style problems and is ready for submission.

Matt

> > +	if (num_sched_list) {
> > +		if (sched_list[0]->sched_policy !=
> > +		    DRM_SCHED_POLICY_SINGLE_ENTITY) {
> > +			entity->rq = &sched_list[0]->sched_rq[entity->priority];
> > +		} else if (num_sched_list == 1 && !sched_list[0]->single_entity) {
> > +			sched_list[0]->single_entity = entity;
> > +			entity->single_sched = sched_list[0];
> > +		} else {
> > +			return -EINVAL;
> > +		}
> > +	}
> >  
> >  	init_completion(&entity->entity_idle);
> >  
> > @@ -124,7 +135,8 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
> >  				    struct drm_gpu_scheduler **sched_list,
> >  				    unsigned int num_sched_list)
> >  {
> > -	WARN_ON(!num_sched_list || !sched_list);
> > +	WARN_ON(!num_sched_list || !sched_list ||
> > +		!!entity->single_sched);
> >  
> >  	entity->sched_list = sched_list;
> >  	entity->num_sched_list = num_sched_list;
> > @@ -231,13 +243,15 @@ static void drm_sched_entity_kill(struct drm_sched_entity *entity)
> >  {
> >  	struct drm_sched_job *job;
> >  	struct dma_fence *prev;
> > +	bool single_entity = !!entity->single_sched;
> >  
> > -	if (!entity->rq)
> > +	if (!entity->rq && !single_entity)
> >  		return;
> >  
> >  	spin_lock(&entity->rq_lock);
> >  	entity->stopped = true;
> > -	drm_sched_rq_remove_entity(entity->rq, entity);
> > +	if (!single_entity)
> > +		drm_sched_rq_remove_entity(entity->rq, entity);
> >  	spin_unlock(&entity->rq_lock);
> >  
> >  	/* Make sure this entity is not used by the scheduler at the moment */
> > @@ -259,6 +273,20 @@ static void drm_sched_entity_kill(struct drm_sched_entity *entity)
> >  	dma_fence_put(prev);
> >  }
> >  
> > +/**
> > + * drm_sched_entity_to_scheduler - Schedule entity to GPU scheduler
> > + * @entity: scheduler entity
> > + *
> > + * Returns GPU scheduler for the entity
> > + */
> > +struct drm_gpu_scheduler *
> > +drm_sched_entity_to_scheduler(struct drm_sched_entity *entity)
> > +{
> > +	bool single_entity = !!entity->single_sched;
> > +
> > +	return single_entity ? entity->single_sched : entity->rq->sched;
> > +}
> > +
> >  /**
> >   * drm_sched_entity_flush - Flush a context entity
> >   *
> > @@ -276,11 +304,12 @@ long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout)
> >  	struct drm_gpu_scheduler *sched;
> >  	struct task_struct *last_user;
> >  	long ret = timeout;
> > +	bool single_entity = !!entity->single_sched;
> >  
> > -	if (!entity->rq)
> > +	if (!entity->rq && !single_entity)
> >  		return 0;
> >  
> > -	sched = entity->rq->sched;
> > +	sched = drm_sched_entity_to_scheduler(entity);
> >  	/**
> >  	 * The client will not queue more IBs during this fini, consume existing
> >  	 * queued IBs or discard them on SIGKILL
> > @@ -373,7 +402,7 @@ static void drm_sched_entity_wakeup(struct dma_fence *f,
> >  		container_of(cb, struct drm_sched_entity, cb);
> >  
> >  	drm_sched_entity_clear_dep(f, cb);
> > -	drm_sched_wakeup_if_can_queue(entity->rq->sched);
> > +	drm_sched_wakeup_if_can_queue(drm_sched_entity_to_scheduler(entity));
> >  }
> >  
> >  /**
> > @@ -387,6 +416,8 @@ static void drm_sched_entity_wakeup(struct dma_fence *f,
> >  void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
> >  				   enum drm_sched_priority priority)
> >  {
> > +	WARN_ON(!!entity->single_sched);
> > +
> >  	spin_lock(&entity->rq_lock);
> >  	entity->priority = priority;
> >  	spin_unlock(&entity->rq_lock);
> > @@ -399,7 +430,7 @@ EXPORT_SYMBOL(drm_sched_entity_set_priority);
> >   */
> >  static bool drm_sched_entity_add_dependency_cb(struct drm_sched_entity *entity)
> >  {
> > -	struct drm_gpu_scheduler *sched = entity->rq->sched;
> > +	struct drm_gpu_scheduler *sched = drm_sched_entity_to_scheduler(entity);
> >  	struct dma_fence *fence = entity->dependency;
> >  	struct drm_sched_fence *s_fence;
> >  
> > @@ -501,7 +532,8 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
> >  	 * Update the entity's location in the min heap according to
> >  	 * the timestamp of the next job, if any.
> >  	 */
> > -	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
> > +	if (drm_sched_entity_to_scheduler(entity)->sched_policy ==
> > +	    DRM_SCHED_POLICY_FIFO) {
> >  		struct drm_sched_job *next;
> >  
> >  		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
> > @@ -524,6 +556,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
> >  	struct drm_gpu_scheduler *sched;
> >  	struct drm_sched_rq *rq;
> >  
> > +	WARN_ON(!!entity->single_sched);
> > +
> >  	/* single possible engine and already selected */
> >  	if (!entity->sched_list)
> >  		return;
> > @@ -573,12 +607,13 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
> >  void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
> >  {
> >  	struct drm_sched_entity *entity = sched_job->entity;
> > -	bool first, fifo = entity->rq->sched->sched_policy ==
> > -		DRM_SCHED_POLICY_FIFO;
> > +	bool single_entity = !!entity->single_sched;
> > +	bool first;
> >  	ktime_t submit_ts;
> >  
> >  	trace_drm_sched_job(sched_job, entity);
> > -	atomic_inc(entity->rq->sched->score);
> > +	if (!single_entity)
> > +		atomic_inc(entity->rq->sched->score);
> >  	WRITE_ONCE(entity->last_user, current->group_leader);
> >  
> >  	/*
> > @@ -591,6 +626,10 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
> >  
> >  	/* first job wakes up scheduler */
> >  	if (first) {
> > +		struct drm_gpu_scheduler *sched =
> > +			drm_sched_entity_to_scheduler(entity);
> > +		bool fifo = sched->sched_policy == DRM_SCHED_POLICY_FIFO;
> > +
> >  		/* Add the entity to the run queue */
> >  		spin_lock(&entity->rq_lock);
> >  		if (entity->stopped) {
> > @@ -600,13 +639,14 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
> >  			return;
> >  		}
> >  
> > -		drm_sched_rq_add_entity(entity->rq, entity);
> > +		if (!single_entity)
> > +			drm_sched_rq_add_entity(entity->rq, entity);
> >  		spin_unlock(&entity->rq_lock);
> >  
> >  		if (fifo)
> >  			drm_sched_rq_update_fifo(entity, submit_ts);
> >  
> > -		drm_sched_wakeup_if_can_queue(entity->rq->sched);
> > +		drm_sched_wakeup_if_can_queue(sched);
> >  	}
> >  }
> >  EXPORT_SYMBOL(drm_sched_entity_push_job);
> > diff --git a/drivers/gpu/drm/scheduler/sched_fence.c b/drivers/gpu/drm/scheduler/sched_fence.c
> > index 06cedfe4b486..f6b926f5e188 100644
> > --- a/drivers/gpu/drm/scheduler/sched_fence.c
> > +++ b/drivers/gpu/drm/scheduler/sched_fence.c
> > @@ -225,7 +225,7 @@ void drm_sched_fence_init(struct drm_sched_fence *fence,
> >  {
> >  	unsigned seq;
> >  
> > -	fence->sched = entity->rq->sched;
> > +	fence->sched = drm_sched_entity_to_scheduler(entity);
> >  	seq = atomic_inc_return(&entity->fence_seq);
> >  	dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled,
> >  		       &fence->lock, entity->fence_context, seq);
> > diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> > index 150e5330f0fa..7dbb3392124d 100644
> > --- a/drivers/gpu/drm/scheduler/sched_main.c
> > +++ b/drivers/gpu/drm/scheduler/sched_main.c
> > @@ -32,7 +32,8 @@
> >   * backend operations to the scheduler like submitting a job to hardware run queue,
> >   * returning the dependencies of a job etc.
> >   *
> > - * The organisation of the scheduler is the following:
> > + * For scheduling policies DRM_SCHED_POLICY_RR and DRM_SCHED_POLICY_FIFO, the
> > + * scheduler organization is:
> >   *
> >   * 1. Each hw run queue has one scheduler
> >   * 2. Each scheduler has multiple run queues with different priorities
> > @@ -43,7 +44,24 @@
> >   *
> >   * The jobs in a entity are always scheduled in the order that they were pushed.
> >   *
> > - * Note that once a job was taken from the entities queue and pushed to the
> > + * For DRM_SCHED_POLICY_SINGLE_ENTITY, the organization of the scheduler is:
> > + *
> > + * 1. One to one relationship between scheduler and entity
> > + * 2. No priorities implemented per scheduler (single job queue)
> > + * 3. No run queues in scheduler rather jobs are directly dequeued from entity
> > + * 4. The entity maintains a queue of jobs that will be scheduled to the
> > + * hardware
> > + *
> > + * The jobs in a entity are always scheduled in the order that they were pushed
> > + * regardless of scheduling policy. Single-entity scheduling is essentially a
> > + * FIFO for jobs.
> > + *
> > + * A policy of DRM_SCHED_POLICY_RR or DRM_SCHED_POLICY_FIFO is expected to be
> > + * used when the kernel-mode driver is scheduling directly to the hardware while
> > + * a scheduling policy of DRM_SCHED_POLICY_SINGLE_ENTITY is expected to be used
> > + * when there is a firmware scheduler.
> > + *
> > + * Note that once a job is taken from the entities queue and pushed to the
> >   * hardware, i.e. the pending queue, the entity must not be referenced anymore
> >   * through the jobs entity pointer.
> >   */
> > @@ -96,6 +114,8 @@ static inline void drm_sched_rq_remove_fifo_locked(struct drm_sched_entity *enti
> >  
> >  void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
> >  {
> > +	WARN_ON(!!entity->single_sched);
> > +
> >  	/*
> >  	 * Both locks need to be grabbed, one to protect from entity->rq change
> >  	 * for entity from within concurrent drm_sched_entity_select_rq and the
> > @@ -126,6 +146,8 @@ void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
> >  static void drm_sched_rq_init(struct drm_gpu_scheduler *sched,
> >  			      struct drm_sched_rq *rq)
> >  {
> > +	WARN_ON(sched->sched_policy == DRM_SCHED_POLICY_SINGLE_ENTITY);
> > +
> >  	spin_lock_init(&rq->lock);
> >  	INIT_LIST_HEAD(&rq->entities);
> >  	rq->rb_tree_root = RB_ROOT_CACHED;
> > @@ -144,6 +166,8 @@ static void drm_sched_rq_init(struct drm_gpu_scheduler *sched,
> >  void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
> >  			     struct drm_sched_entity *entity)
> >  {
> > +	WARN_ON(!!entity->single_sched);
> > +
> >  	if (!list_empty(&entity->list))
> >  		return;
> >  
> > @@ -166,6 +190,8 @@ void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
> >  void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
> >  				struct drm_sched_entity *entity)
> >  {
> > +	WARN_ON(!!entity->single_sched);
> > +
> >  	if (list_empty(&entity->list))
> >  		return;
> >  
> > @@ -641,7 +667,7 @@ int drm_sched_job_init(struct drm_sched_job *job,
> >  		       struct drm_sched_entity *entity,
> >  		       void *owner)
> >  {
> > -	if (!entity->rq)
> > +	if (!entity->rq && !entity->single_sched)
> >  		return -ENOENT;
> >  
> >  	job->entity = entity;
> > @@ -674,13 +700,16 @@ void drm_sched_job_arm(struct drm_sched_job *job)
> >  {
> >  	struct drm_gpu_scheduler *sched;
> >  	struct drm_sched_entity *entity = job->entity;
> > +	bool single_entity = !!entity->single_sched;
> >  
> >  	BUG_ON(!entity);
> > -	drm_sched_entity_select_rq(entity);
> > -	sched = entity->rq->sched;
> > +	if (!single_entity)
> > +		drm_sched_entity_select_rq(entity);
> > +	sched = drm_sched_entity_to_scheduler(entity);
> >  
> >  	job->sched = sched;
> > -	job->s_priority = entity->rq - sched->sched_rq;
> > +	if (!single_entity)
> > +		job->s_priority = entity->rq - sched->sched_rq;
> >  	job->id = atomic64_inc_return(&sched->job_id_count);
> >  
> >  	drm_sched_fence_init(job->s_fence, job->entity);
> > @@ -896,6 +925,14 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
> >  	if (!drm_sched_can_queue(sched))
> >  		return NULL;
> >  
> > +	if (sched->single_entity) {
> > +		if (!READ_ONCE(sched->single_entity->stopped) &&
> > +		    drm_sched_entity_is_ready(sched->single_entity))
> > +			return sched->single_entity;
> > +
> > +		return NULL;
> > +	}
> > +
> >  	/* Kernel run queue has higher priority than normal run queue*/
> >  	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> >  		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
> > @@ -1092,6 +1129,7 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> >  		return -EINVAL;
> >  
> >  	sched->ops = ops;
> > +	sched->single_entity = NULL;
> >  	sched->hw_submission_limit = hw_submission;
> >  	sched->name = name;
> >  	if (submit_wq) {
> > @@ -1111,8 +1149,10 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> >  	sched->dev = dev;
> >  	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
> >  		drm_sched_policy_default : sched_policy;
> > -	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
> > -		drm_sched_rq_init(sched, &sched->sched_rq[i]);
> > +	if (sched_policy != DRM_SCHED_POLICY_SINGLE_ENTITY) {
> > +		for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
> > +			drm_sched_rq_init(sched, &sched->sched_rq[i]);
> > +	}
> >  
> >  	init_waitqueue_head(&sched->job_scheduled);
> >  	INIT_LIST_HEAD(&sched->pending_list);
> > @@ -1143,19 +1183,25 @@ void drm_sched_fini(struct drm_gpu_scheduler *sched)
> >  
> >  	drm_sched_wqueue_stop(sched);
> >  
> > -	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> > -		struct drm_sched_rq *rq = &sched->sched_rq[i];
> > +	if (sched->single_entity) {
> > +		spin_lock(&sched->single_entity->rq_lock);
> > +		sched->single_entity->stopped = true;
> > +		spin_unlock(&sched->single_entity->rq_lock);
> > +	} else if (sched->sched_policy != DRM_SCHED_POLICY_SINGLE_ENTITY) {
> > +		for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> > +			struct drm_sched_rq *rq = &sched->sched_rq[i];
> >  
> > -		spin_lock(&rq->lock);
> > -		list_for_each_entry(s_entity, &rq->entities, list)
> > -			/*
> > -			 * Prevents reinsertion and marks job_queue as idle,
> > -			 * it will removed from rq in drm_sched_entity_fini
> > -			 * eventually
> > -			 */
> > -			s_entity->stopped = true;
> > -		spin_unlock(&rq->lock);
> > +			spin_lock(&rq->lock);
> > +			list_for_each_entry(s_entity, &rq->entities, list)
> > +				/*
> > +				 * Prevents reinsertion and marks job_queue as idle,
> > +				 * it will removed from rq in drm_sched_entity_fini
> > +				 * eventually
> > +				 */
> > +				s_entity->stopped = true;
> > +			spin_unlock(&rq->lock);
> >  
> > +		}
> 
> ^ Blank lines aren't necessary before a closing brace.
> 
> I've fixed both of these locally, and would like to try something before R-V-ing this patch.
> 
> >  	}
> >  
> >  	/* Wakeup everyone stuck in drm_sched_entity_flush for this scheduler */
> > @@ -1186,6 +1232,8 @@ void drm_sched_increase_karma(struct drm_sched_job *bad)
> >  	struct drm_sched_entity *entity;
> >  	struct drm_gpu_scheduler *sched = bad->sched;
> >  
> > +	WARN_ON(sched->sched_policy == DRM_SCHED_POLICY_SINGLE_ENTITY);
> > +
> >  	/* don't change @bad's karma if it's from KERNEL RQ,
> >  	 * because sometimes GPU hang would cause kernel jobs (like VM updating jobs)
> >  	 * corrupt but keep in mind that kernel jobs always considered good.
> > diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> > index 320f0a720486..e67b53c3546b 100644
> > --- a/include/drm/gpu_scheduler.h
> > +++ b/include/drm/gpu_scheduler.h
> > @@ -79,6 +79,7 @@ enum drm_sched_policy {
> >  	DRM_SCHED_POLICY_UNSET,
> >  	DRM_SCHED_POLICY_RR,
> >  	DRM_SCHED_POLICY_FIFO,
> > +	DRM_SCHED_POLICY_SINGLE_ENTITY,
> >  	DRM_SCHED_POLICY_COUNT,
> >  };
> >  
> > @@ -112,6 +113,9 @@ struct drm_sched_entity {
> >  	 */
> >  	struct drm_sched_rq		*rq;
> >  
> > +	/** @single_sched: Single scheduler */
> > +	struct drm_gpu_scheduler	*single_sched;
> > +
> >  	/**
> >  	 * @sched_list:
> >  	 *
> > @@ -473,6 +477,7 @@ struct drm_sched_backend_ops {
> >   * struct drm_gpu_scheduler - scheduler instance-specific data
> >   *
> >   * @ops: backend operations provided by the driver.
> > + * @single_entity: Single entity for the scheduler
> >   * @hw_submission_limit: the max size of the hardware queue.
> >   * @timeout: the time after which a job is removed from the scheduler.
> >   * @name: name of the ring for which this scheduler is being used.
> > @@ -504,6 +509,7 @@ struct drm_sched_backend_ops {
> >   */
> >  struct drm_gpu_scheduler {
> >  	const struct drm_sched_backend_ops	*ops;
> > +	struct drm_sched_entity		*single_entity;
> >  	uint32_t			hw_submission_limit;
> >  	long				timeout;
> >  	const char			*name;
> > @@ -587,6 +593,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
> >  			  struct drm_gpu_scheduler **sched_list,
> >  			  unsigned int num_sched_list,
> >  			  atomic_t *guilty);
> > +struct drm_gpu_scheduler *
> > +drm_sched_entity_to_scheduler(struct drm_sched_entity *entity);
> >  long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout);
> >  void drm_sched_entity_fini(struct drm_sched_entity *entity);
> >  void drm_sched_entity_destroy(struct drm_sched_entity *entity);
> 
> -- 
> Regards,
> Luben
> 

Re: [PATCH v5 7/7] drm/sched: Add helper to queue TDR immediately for current and future jobs

[Matthew Brost]

On Fri, Oct 13, 2023 at 11:04:47PM -0400, Luben Tuikov wrote:
> On 2023-10-11 19:58, Matthew Brost wrote:
> > Add helper to queue TDR immediately for current and future jobs. This is
> > used in Xe, a new Intel GPU driver, to trigger a TDR to cleanup a
> > drm_scheduler that encounter errors.
> 
> I think the best (most optimal) thing to do is to remove the last sentence
> mentioning Xe. It is irrelevant to this patch. This patch is functional
> as is, and worth having it as is.
> 
> So it's best to have just:
> 
> 	Add a helper whereby a driver can invoke TDR immediately.
> 

+1.

> Also remove "for current and future jobs" from the title, as it is
> implied by how TDR works. We want to say less.
> 
> 	drm/sched: Add a helper to queue TDR immediately
>

Yep, my bad I forgot to adjust the commit message in this rev. Will fix.

Matt

> These are only GPU scheduler changes, worth having on their own. The fact
> that a new (future as of this moment) driver (Xe) would use them is irrelevant
> at the moment. Other drivers (new, current?) would most likely end up using the changes
> of these patches, and these changes go in on their own merit.
> 
> Regards,
> Luben
> 
> > 
> > v2:
> >  - Drop timeout args, rename function, use mod delayed work (Luben)
> > v3:
> >  - s/XE/Xe (Luben)
> >  - present tense in commit message (Luben)
> >  - Adjust comment for drm_sched_tdr_queue_imm (Luben)
> > 
> > Cc: Luben Tuikov <luben.tuikov@amd.com>
> > Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> > ---
> >  drivers/gpu/drm/scheduler/sched_main.c | 18 +++++++++++++++++-
> >  include/drm/gpu_scheduler.h            |  1 +
> >  2 files changed, 18 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> > index c4d5c3d265a8..f2846745b067 100644
> > --- a/drivers/gpu/drm/scheduler/sched_main.c
> > +++ b/drivers/gpu/drm/scheduler/sched_main.c
> > @@ -431,7 +431,7 @@ static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
> >  
> >  	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
> >  	    !list_empty(&sched->pending_list))
> > -		queue_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
> > +		mod_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
> >  }
> >  
> >  static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
> > @@ -441,6 +441,22 @@ static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
> >  	spin_unlock(&sched->job_list_lock);
> >  }
> >  
> > +/**
> > + * drm_sched_tdr_queue_imm: - immediately start job timeout handler
> > + *
> > + * @sched: scheduler for which the timeout handling should be started.
> > + *
> > + * Start timeout handling immediately for the named scheduler.
> > + */
> > +void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched)
> > +{
> > +	spin_lock(&sched->job_list_lock);
> > +	sched->timeout = 0;
> > +	drm_sched_start_timeout(sched);
> > +	spin_unlock(&sched->job_list_lock);
> > +}
> > +EXPORT_SYMBOL(drm_sched_tdr_queue_imm);
> > +
> >  /**
> >   * drm_sched_fault - immediately start timeout handler
> >   *
> > diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> > index 625ffe040de3..998b32b8d212 100644
> > --- a/include/drm/gpu_scheduler.h
> > +++ b/include/drm/gpu_scheduler.h
> > @@ -568,6 +568,7 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
> >  				    struct drm_gpu_scheduler **sched_list,
> >                                     unsigned int num_sched_list);
> >  
> > +void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched);
> >  void drm_sched_job_cleanup(struct drm_sched_job *job);
> >  void drm_sched_wakeup_if_can_queue(struct drm_gpu_scheduler *sched);
> >  bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched);
> 

Re: [PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Matthew Brost]

On Fri, Oct 13, 2023 at 01:45:08PM -0400, Luben Tuikov wrote:
> On 2023-10-11 19:58, Matthew Brost wrote:
> > Rather than a global modparam for scheduling policy, move the scheduling
> > policy to scheduler so user can control each scheduler policy.
> > 
> > v2:
> >   - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
> >   - Only include policy in scheduler (Luben)
> > v3:
> >   - use a ternary operator as opposed to an if-control (Luben)
> >   - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
> >   - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
> >   - Update commit message (Boris)
> >   - Fix v3d build (CI)
> >   - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
> >   - Don't update modparam doc (Luben)
> > v4:
> >   - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)
> > 
> > Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
> > Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> 
> Hi,
> 
> Forgot to mention this, but it is a very important process to note,
> is that one should _never_ add someone else's R-V tag, _*UNLESS*_
> a) there's an email from the person giving their review or ack, and
> b) you're the one pushing the patch set into the tree.
> If you're not the one pushing it into the tree, the maintainer will
> add their R-V (after their reply-to follow-up email--see below),
> including a Link: tag when they do "git am" after it's been all reviewed.
> 
> And there's a reason for this.
> 
> The reason is that when kernel maintainers (especially DRM via dim[1]) push
> patches into the kernel, we want to add a Link: tag [2,3] pointing to
> the thread where a) the patch was posted and b) where the reviewer gave
> their Reviewed-by to the patch in a reply-all email, and at this moment
> there is no such email for this patch.
> 
> When a maintainer says "Do X, Y, Z, for an immediate R-V", this means
> do those things, post it, and get a reply from the maintainer with an
> R-V. This records how it happened and is very helpful when doing
> data mining on how and why the code changed, via what patches, etc.
> 
> I suspect there might be a v6, and we can do the R-V/Ack the right way
> at that time. No big deal, but it's good to know in one place as it
> is a bit scatter here and there in the kernel-doc.
> 
> [1] https://gitlab.freedesktop.org/drm/maintainer-tools/
> [2] git am --message-id
> [3] https://docs.kernel.org/maintainer/
> -- 
> Regards,
> Luben
> 

Again thanks for all the details of the development flow. Will read up
on all of this.

Just to be to clear, when I post a rev6 I should not include a RB in the
patches that recieved an RB in rev5 (or prior revs)? Rather a Cc would
be better to alert the reviewer of another rev?

Matt 

> > ---
> >  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  1 +
> >  drivers/gpu/drm/etnaviv/etnaviv_sched.c    |  3 ++-
> >  drivers/gpu/drm/lima/lima_sched.c          |  3 ++-
> >  drivers/gpu/drm/msm/msm_ringbuffer.c       |  2 +-
> >  drivers/gpu/drm/nouveau/nouveau_sched.c    |  3 ++-
> >  drivers/gpu/drm/panfrost/panfrost_job.c    |  3 ++-
> >  drivers/gpu/drm/scheduler/sched_entity.c   | 24 ++++++++++++++++++----
> >  drivers/gpu/drm/scheduler/sched_main.c     | 19 ++++++++++++-----
> >  drivers/gpu/drm/v3d/v3d_sched.c            | 15 +++++++++-----
> >  include/drm/gpu_scheduler.h                | 20 ++++++++++++------
> >  10 files changed, 68 insertions(+), 25 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > index b54c4d771104..e4e6f91450a4 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> > @@ -2283,6 +2283,7 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
> >  				   ring->num_hw_submission, 0,
> >  				   timeout, adev->reset_domain->wq,
> >  				   ring->sched_score, ring->name,
> > +				   DRM_SCHED_POLICY_UNSET,
> >  				   adev->dev);
> >  		if (r) {
> >  			DRM_ERROR("Failed to create scheduler on ring %s.\n",
> > diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> > index 618a804ddc34..15b0e2f1abe5 100644
> > --- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> > +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
> > @@ -137,7 +137,8 @@ int etnaviv_sched_init(struct etnaviv_gpu *gpu)
> >  	ret = drm_sched_init(&gpu->sched, &etnaviv_sched_ops, NULL,
> >  			     etnaviv_hw_jobs_limit, etnaviv_job_hang_limit,
> >  			     msecs_to_jiffies(500), NULL, NULL,
> > -			     dev_name(gpu->dev), gpu->dev);
> > +			     dev_name(gpu->dev), DRM_SCHED_POLICY_UNSET,
> > +			     gpu->dev);
> >  	if (ret)
> >  		return ret;
> >  
> > diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
> > index 8d858aed0e56..50c2075228aa 100644
> > --- a/drivers/gpu/drm/lima/lima_sched.c
> > +++ b/drivers/gpu/drm/lima/lima_sched.c
> > @@ -491,7 +491,8 @@ int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
> >  	return drm_sched_init(&pipe->base, &lima_sched_ops, NULL, 1,
> >  			      lima_job_hang_limit,
> >  			      msecs_to_jiffies(timeout), NULL,
> > -			      NULL, name, pipe->ldev->dev);
> > +			      NULL, name, DRM_SCHED_POLICY_UNSET,
> > +			      pipe->ldev->dev);
> >  }
> >  
> >  void lima_sched_pipe_fini(struct lima_sched_pipe *pipe)
> > diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
> > index 1097f8e93d6b..173ad2f17c50 100644
> > --- a/drivers/gpu/drm/msm/msm_ringbuffer.c
> > +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
> > @@ -97,7 +97,7 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
> >  	ret = drm_sched_init(&ring->sched, &msm_sched_ops, NULL,
> >  			     num_hw_submissions, 0, sched_timeout,
> >  			     NULL, NULL, to_msm_bo(ring->bo)->name,
> > -			     gpu->dev->dev);
> > +			     DRM_SCHED_POLICY_UNSET, gpu->dev->dev);
> >  	if (ret) {
> >  		goto fail;
> >  	}
> > diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
> > index 4c959dec42b3..c4e09d2e77f9 100644
> > --- a/drivers/gpu/drm/nouveau/nouveau_sched.c
> > +++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
> > @@ -437,7 +437,8 @@ int nouveau_sched_init(struct nouveau_drm *drm)
> >  
> >  	return drm_sched_init(sched, &nouveau_sched_ops, NULL,
> >  			      NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
> > -			      NULL, NULL, "nouveau_sched", drm->dev->dev);
> > +			      NULL, NULL, "nouveau_sched",
> > +			      DRM_SCHED_POLICY_UNSET, drm->dev->dev);
> >  }
> >  
> >  void nouveau_sched_fini(struct nouveau_drm *drm)
> > diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
> > index 934b7b930c76..95330ff402ba 100644
> > --- a/drivers/gpu/drm/panfrost/panfrost_job.c
> > +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> > @@ -856,7 +856,8 @@ int panfrost_job_init(struct panfrost_device *pfdev)
> >  				     nentries, 0,
> >  				     msecs_to_jiffies(JOB_TIMEOUT_MS),
> >  				     pfdev->reset.wq,
> > -				     NULL, "pan_js", pfdev->dev);
> > +				     NULL, "pan_js", DRM_SCHED_POLICY_UNSET,
> > +				     pfdev->dev);
> >  		if (ret) {
> >  			dev_err(pfdev->dev, "Failed to create scheduler: %d.", ret);
> >  			goto err_sched;
> > diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> > index a42763e1429d..cf42e2265d64 100644
> > --- a/drivers/gpu/drm/scheduler/sched_entity.c
> > +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> > @@ -33,6 +33,20 @@
> >  #define to_drm_sched_job(sched_job)		\
> >  		container_of((sched_job), struct drm_sched_job, queue_node)
> >  
> > +static bool drm_sched_policy_mismatch(struct drm_gpu_scheduler **sched_list,
> > +				      unsigned int num_sched_list)
> > +{
> > +	enum drm_sched_policy sched_policy = sched_list[0]->sched_policy;
> > +	unsigned int i;
> > +
> > +	/* All schedule policies must match */
> > +	for (i = 1; i < num_sched_list; ++i)
> > +		if (sched_policy != sched_list[i]->sched_policy)
> > +			return true;
> > +
> > +	return false;
> > +}
> > +
> >  /**
> >   * drm_sched_entity_init - Init a context entity used by scheduler when
> >   * submit to HW ring.
> > @@ -62,7 +76,8 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
> >  			  unsigned int num_sched_list,
> >  			  atomic_t *guilty)
> >  {
> > -	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])))
> > +	if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])) ||
> > +	    drm_sched_policy_mismatch(sched_list, num_sched_list))
> >  		return -EINVAL;
> >  
> >  	memset(entity, 0, sizeof(struct drm_sched_entity));
> > @@ -486,7 +501,7 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
> >  	 * Update the entity's location in the min heap according to
> >  	 * the timestamp of the next job, if any.
> >  	 */
> > -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) {
> > +	if (entity->rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO) {
> >  		struct drm_sched_job *next;
> >  
> >  		next = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
> > @@ -558,7 +573,8 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
> >  void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
> >  {
> >  	struct drm_sched_entity *entity = sched_job->entity;
> > -	bool first;
> > +	bool first, fifo = entity->rq->sched->sched_policy ==
> > +		DRM_SCHED_POLICY_FIFO;
> >  	ktime_t submit_ts;
> >  
> >  	trace_drm_sched_job(sched_job, entity);
> > @@ -587,7 +603,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
> >  		drm_sched_rq_add_entity(entity->rq, entity);
> >  		spin_unlock(&entity->rq_lock);
> >  
> > -		if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> > +		if (fifo)
> >  			drm_sched_rq_update_fifo(entity, submit_ts);
> >  
> >  		drm_sched_wakeup_if_can_queue(entity->rq->sched);
> > diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> > index 8b1d52cff1e9..150e5330f0fa 100644
> > --- a/drivers/gpu/drm/scheduler/sched_main.c
> > +++ b/drivers/gpu/drm/scheduler/sched_main.c
> > @@ -66,14 +66,14 @@
> >  #define to_drm_sched_job(sched_job)		\
> >  		container_of((sched_job), struct drm_sched_job, queue_node)
> >  
> > -int drm_sched_policy = DRM_SCHED_POLICY_FIFO;
> > +int drm_sched_policy_default = DRM_SCHED_POLICY_FIFO;
> >  
> >  /**
> >   * DOC: sched_policy (int)
> >   * Used to override default entities scheduling policy in a run queue.
> >   */
> >  MODULE_PARM_DESC(sched_policy, "Specify the scheduling policy for entities on a run-queue, " __stringify(DRM_SCHED_POLICY_RR) " = Round Robin, " __stringify(DRM_SCHED_POLICY_FIFO) " = FIFO (default).");
> > -module_param_named(sched_policy, drm_sched_policy, int, 0444);
> > +module_param_named(sched_policy, drm_sched_policy_default, int, 0444);
> >  
> >  static __always_inline bool drm_sched_entity_compare_before(struct rb_node *a,
> >  							    const struct rb_node *b)
> > @@ -177,7 +177,7 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
> >  	if (rq->current_entity == entity)
> >  		rq->current_entity = NULL;
> >  
> > -	if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> > +	if (rq->sched->sched_policy == DRM_SCHED_POLICY_FIFO)
> >  		drm_sched_rq_remove_fifo_locked(entity);
> >  
> >  	spin_unlock(&rq->lock);
> > @@ -898,7 +898,7 @@ drm_sched_select_entity(struct drm_gpu_scheduler *sched)
> >  
> >  	/* Kernel run queue has higher priority than normal run queue*/
> >  	for (i = DRM_SCHED_PRIORITY_COUNT - 1; i >= DRM_SCHED_PRIORITY_MIN; i--) {
> > -		entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
> > +		entity = sched->sched_policy == DRM_SCHED_POLICY_FIFO ?
> >  			drm_sched_rq_select_entity_fifo(&sched->sched_rq[i]) :
> >  			drm_sched_rq_select_entity_rr(&sched->sched_rq[i]);
> >  		if (entity)
> > @@ -1072,6 +1072,7 @@ static void drm_sched_main(struct work_struct *w)
> >   *		used
> >   * @score: optional score atomic shared with other schedulers
> >   * @name: name used for debugging
> > + * @sched_policy: schedule policy
> >   * @dev: target &struct device
> >   *
> >   * Return 0 on success, otherwise error code.
> > @@ -1081,9 +1082,15 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> >  		   struct workqueue_struct *submit_wq,
> >  		   unsigned hw_submission, unsigned hang_limit,
> >  		   long timeout, struct workqueue_struct *timeout_wq,
> > -		   atomic_t *score, const char *name, struct device *dev)
> > +		   atomic_t *score, const char *name,
> > +		   enum drm_sched_policy sched_policy,
> > +		   struct device *dev)
> >  {
> >  	int i;
> > +
> > +	if (sched_policy >= DRM_SCHED_POLICY_COUNT)
> > +		return -EINVAL;
> > +
> >  	sched->ops = ops;
> >  	sched->hw_submission_limit = hw_submission;
> >  	sched->name = name;
> > @@ -1102,6 +1109,8 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> >  	sched->hang_limit = hang_limit;
> >  	sched->score = score ? score : &sched->_score;
> >  	sched->dev = dev;
> > +	sched->sched_policy = sched_policy == DRM_SCHED_POLICY_UNSET ?
> > +		drm_sched_policy_default : sched_policy;
> >  	for (i = DRM_SCHED_PRIORITY_MIN; i < DRM_SCHED_PRIORITY_COUNT; i++)
> >  		drm_sched_rq_init(sched, &sched->sched_rq[i]);
> >  
> > diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
> > index 38e092ea41e6..dec89c5b8cb1 100644
> > --- a/drivers/gpu/drm/v3d/v3d_sched.c
> > +++ b/drivers/gpu/drm/v3d/v3d_sched.c
> > @@ -391,7 +391,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  			     &v3d_bin_sched_ops, NULL,
> >  			     hw_jobs_limit, job_hang_limit,
> >  			     msecs_to_jiffies(hang_limit_ms), NULL,
> > -			     NULL, "v3d_bin", v3d->drm.dev);
> > +			     NULL, "v3d_bin", DRM_SCHED_POLICY_UNSET,
> > +			     v3d->drm.dev);
> >  	if (ret)
> >  		return ret;
> >  
> > @@ -399,7 +400,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  			     &v3d_render_sched_ops, NULL,
> >  			     hw_jobs_limit, job_hang_limit,
> >  			     msecs_to_jiffies(hang_limit_ms), NULL,
> > -			     NULL, "v3d_render", v3d->drm.dev);
> > +			     NULL, "v3d_render", DRM_SCHED_POLICY_UNSET,
> > +			     v3d->drm.dev);
> >  	if (ret)
> >  		goto fail;
> >  
> > @@ -407,7 +409,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  			     &v3d_tfu_sched_ops, NULL,
> >  			     hw_jobs_limit, job_hang_limit,
> >  			     msecs_to_jiffies(hang_limit_ms), NULL,
> > -			     NULL, "v3d_tfu", v3d->drm.dev);
> > +			     NULL, "v3d_tfu", DRM_SCHED_POLICY_UNSET,
> > +			     v3d->drm.dev);
> >  	if (ret)
> >  		goto fail;
> >  
> > @@ -416,7 +419,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  				     &v3d_csd_sched_ops, NULL,
> >  				     hw_jobs_limit, job_hang_limit,
> >  				     msecs_to_jiffies(hang_limit_ms), NULL,
> > -				     NULL, "v3d_csd", v3d->drm.dev);
> > +				     NULL, "v3d_csd", DRM_SCHED_POLICY_UNSET,
> > +				     v3d->drm.dev);
> >  		if (ret)
> >  			goto fail;
> >  
> > @@ -424,7 +428,8 @@ v3d_sched_init(struct v3d_dev *v3d)
> >  				     &v3d_cache_clean_sched_ops, NULL,
> >  				     hw_jobs_limit, job_hang_limit,
> >  				     msecs_to_jiffies(hang_limit_ms), NULL,
> > -				     NULL, "v3d_cache_clean", v3d->drm.dev);
> > +				     NULL, "v3d_cache_clean",
> > +				     DRM_SCHED_POLICY_UNSET, v3d->drm.dev);
> >  		if (ret)
> >  			goto fail;
> >  	}
> > diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> > index 211bd3cdabdc..320f0a720486 100644
> > --- a/include/drm/gpu_scheduler.h
> > +++ b/include/drm/gpu_scheduler.h
> > @@ -72,11 +72,15 @@ enum drm_sched_priority {
> >  	DRM_SCHED_PRIORITY_UNSET = -2
> >  };
> >  
> > -/* Used to chose between FIFO and RR jobs scheduling */
> > -extern int drm_sched_policy;
> > -
> > -#define DRM_SCHED_POLICY_RR    0
> > -#define DRM_SCHED_POLICY_FIFO  1
> > +/* Used to chose default scheduling policy*/
> > +extern int default_drm_sched_policy;
> > +
> > +enum drm_sched_policy {
> > +	DRM_SCHED_POLICY_UNSET,
> > +	DRM_SCHED_POLICY_RR,
> > +	DRM_SCHED_POLICY_FIFO,
> > +	DRM_SCHED_POLICY_COUNT,
> > +};
> >  
> >  /**
> >   * struct drm_sched_entity - A wrapper around a job queue (typically
> > @@ -489,6 +493,7 @@ struct drm_sched_backend_ops {
> >   *              guilty and it will no longer be considered for scheduling.
> >   * @score: score to help loadbalancer pick a idle sched
> >   * @_score: score used when the driver doesn't provide one
> > + * @sched_policy: Schedule policy for scheduler
> >   * @ready: marks if the underlying HW is ready to work
> >   * @free_guilty: A hit to time out handler to free the guilty job.
> >   * @pause_submit: pause queuing of @work_submit on @submit_wq
> > @@ -515,6 +520,7 @@ struct drm_gpu_scheduler {
> >  	int				hang_limit;
> >  	atomic_t                        *score;
> >  	atomic_t                        _score;
> > +	enum drm_sched_policy		sched_policy;
> >  	bool				ready;
> >  	bool				free_guilty;
> >  	bool				pause_submit;
> > @@ -527,7 +533,9 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
> >  		   struct workqueue_struct *submit_wq,
> >  		   uint32_t hw_submission, unsigned hang_limit,
> >  		   long timeout, struct workqueue_struct *timeout_wq,
> > -		   atomic_t *score, const char *name, struct device *dev);
> > +		   atomic_t *score, const char *name,
> > +		   enum drm_sched_policy sched_policy,
> > +		   struct device *dev);
> >  
> >  void drm_sched_fini(struct drm_gpu_scheduler *sched);
> >  int drm_sched_job_init(struct drm_sched_job *job,
> 

Re: [PATCH v5 4/7] drm/sched: Add DRM_SCHED_POLICY_SINGLE_ENTITY scheduling policy

[Luben Tuikov]

On 2023-10-16 11:00, Matthew Brost wrote:
> On Fri, Oct 13, 2023 at 10:06:18PM -0400, Luben Tuikov wrote:
>> On 2023-10-11 19:58, Matthew Brost wrote:
>>> DRM_SCHED_POLICY_SINGLE_ENTITY creates a 1 to 1 relationship between
>>> scheduler and entity. No priorities or run queue used in this mode.
>>> Intended for devices with firmware schedulers.
>>>
>>> v2:
>>>   - Drop sched / rq union (Luben)
>>> v3:
>>>   - Don't pick entity if stopped in drm_sched_select_entity (Danilo)
>>> v4:
>>>   - Rework if statement in drm_sched_entity_init (Luben)
>>>   - Update comment for drm_sched_entity_to_scheduler (Luben)
>>>   - Reword a few things in DOC comment (Luben)
>>>   - Do not check sched policy in for statement (Luben)
>>>
>>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
>>> ---
>>>  drivers/gpu/drm/scheduler/sched_entity.c | 70 ++++++++++++++-----
>>>  drivers/gpu/drm/scheduler/sched_fence.c  |  2 +-
>>>  drivers/gpu/drm/scheduler/sched_main.c   | 86 ++++++++++++++++++------
>>>  include/drm/gpu_scheduler.h              |  8 +++
>>>  4 files changed, 131 insertions(+), 35 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
>>> index cf42e2265d64..1ef3883764f9 100644
>>> --- a/drivers/gpu/drm/scheduler/sched_entity.c
>>> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
>>> @@ -83,6 +83,7 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>>>  	memset(entity, 0, sizeof(struct drm_sched_entity));
>>>  	INIT_LIST_HEAD(&entity->list);
>>>  	entity->rq = NULL;
>>> +	entity->single_sched = NULL;
>>>  	entity->guilty = guilty;
>>>  	entity->num_sched_list = num_sched_list;
>>>  	entity->priority = priority;
>>> @@ -90,8 +91,18 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>>>  	RCU_INIT_POINTER(entity->last_scheduled, NULL);
>>>  	RB_CLEAR_NODE(&entity->rb_tree_node);
>>>  
>>> -	if(num_sched_list)
>>> -		entity->rq = &sched_list[0]->sched_rq[entity->priority];
>>> +
>>
>> ^ This adds an extra blank line and scripts/checkpatch.pl rejects it.
>>
> 
> Agree this isn't correct, will fix.
> 
> Question - catch patch doesn't complain for me though. Wondering what I
> am missing:
> 
> mbrost@lstrano-desk:drivers.gpu.i915.drm-intel$ ./scripts/checkpatch.pl drivers/gpu/drm/i915/0004-drm-sched-Add-DRM_SCHED_POLICY_SINGLE_ENTITY-schedul.patch
> total: 0 errors, 0 warnings, 386 lines checked
> 
> drivers/gpu/drm/i915/0004-drm-sched-Add-DRM_SCHED_POLICY_SINGLE_ENTITY-schedul.patch has no obvious style problems and is ready for submission.

Use this "--strict --emacs --show-types --codespell".
-- 
Regards,
Luben

Re: [PATCH v5 5/7] drm/sched: Split free_job into own work item

[Matthew Brost]

On Sat, Oct 14, 2023 at 08:09:31PM -0400, Luben Tuikov wrote:
> On 2023-10-13 22:49, Luben Tuikov wrote:
> > On 2023-10-11 19:58, Matthew Brost wrote:
> >> Rather than call free_job and run_job in same work item have a dedicated
> >> work item for each. This aligns with the design and intended use of work
> >> queues.
> >>
> >> v2:
> >>    - Test for DMA_FENCE_FLAG_TIMESTAMP_BIT before setting
> >>      timestamp in free_job() work item (Danilo)
> >> v3:
> >>   - Drop forward dec of drm_sched_select_entity (Boris)
> >>   - Return in drm_sched_run_job_work if entity NULL (Boris)
> >> v4:
> >>   - Replace dequeue with peek and invert logic (Luben)
> >>   - Wrap to 100 lines (Luben)
> >>   - Update comments for *_queue / *_queue_if_ready functions (Luben)
> >>
> >> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> > 
> > I wasn't able to apply this patch on top of drm-misc-next at a48e2cc92835fa.
> > 
> > Create a branch off of a *clean* drm-misc-next and rebase/reapply/cherry-pick all
> > 7 patches on top of that clean drm-misc-next branch. You should also run
> > scripts/checkpatch.pl --strict on all your patches, or integrate it into the precommit
> > hook, see githooks(5), so you don't have to run it manually.
> > 
> > Set format.useAutobase to whenAble somewhere in your Git configs (global/local),
> > or use --base=auto to git-format-patch when you format your patches before
> > git-send-email-ing them.
> > 
> > Repost your patches.
> > 
> > The base commit will be added to the bottom of the cover letter. It should
> > be an ancestor (or tip) of drm-misc-next (git branch --contains <base> --list etc.).
> > If it is not, your base tree wasn't clean, and you should redo this process.
> 
> Poking around I found out that this patch set is based off of drm-misc-fixes.
> Had the base been included, it would've made this easier.

I believe I based this off of drm-tip. Will follow the flow mentioned above in next rev.

Matt

> -- 
> Regards,
> Luben
> 

Re: [PATCH v5 6/7] drm/sched: Add drm_sched_start_timeout_unlocked helper

[Luben Tuikov]

On 2023-10-16 10:57, Matthew Brost wrote:
> On Fri, Oct 13, 2023 at 10:52:22PM -0400, Luben Tuikov wrote:
>> On 2023-10-11 19:58, Matthew Brost wrote:
>>> Also add a lockdep assert to drm_sched_start_timeout.
>>>
>>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
>>> Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
>>
>> I don't remember sending a Reviewed-by email to this patch.
>>
> 
> I believe you did send a RB:
> https://patchwork.freedesktop.org/patch/558222/?series=121745&rev=6
> 
>> I'll add the R-V to the commit when I apply and push this patch,
>> after replying with a R-V email.
>>
> 
> Is manually adding a RB ok if it is in the correct place like it is in this patch?

If you've received an R-B email and you're reposting the patch, you should
append the R-B tag at the bottom of the other tags, like a tool would do it.
-- 
Regards,
Luben

Re: [PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Luben Tuikov]

On 2023-10-16 11:08, Matthew Brost wrote:
> On Fri, Oct 13, 2023 at 01:45:08PM -0400, Luben Tuikov wrote:
>> On 2023-10-11 19:58, Matthew Brost wrote:
>>> Rather than a global modparam for scheduling policy, move the scheduling
>>> policy to scheduler so user can control each scheduler policy.
>>>
>>> v2:
>>>   - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
>>>   - Only include policy in scheduler (Luben)
>>> v3:
>>>   - use a ternary operator as opposed to an if-control (Luben)
>>>   - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
>>>   - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
>>>   - Update commit message (Boris)
>>>   - Fix v3d build (CI)
>>>   - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
>>>   - Don't update modparam doc (Luben)
>>> v4:
>>>   - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)
>>>
>>> Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
>>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
>>
>> Hi,
>>
>> Forgot to mention this, but it is a very important process to note,
>> is that one should _never_ add someone else's R-V tag, _*UNLESS*_
>> a) there's an email from the person giving their review or ack, and
>> b) you're the one pushing the patch set into the tree.
>> If you're not the one pushing it into the tree, the maintainer will
>> add their R-V (after their reply-to follow-up email--see below),
>> including a Link: tag when they do "git am" after it's been all reviewed.
>>
>> And there's a reason for this.
>>
>> The reason is that when kernel maintainers (especially DRM via dim[1]) push
>> patches into the kernel, we want to add a Link: tag [2,3] pointing to
>> the thread where a) the patch was posted and b) where the reviewer gave
>> their Reviewed-by to the patch in a reply-all email, and at this moment
>> there is no such email for this patch.
>>
>> When a maintainer says "Do X, Y, Z, for an immediate R-V", this means
>> do those things, post it, and get a reply from the maintainer with an
>> R-V. This records how it happened and is very helpful when doing
>> data mining on how and why the code changed, via what patches, etc.
>>
>> I suspect there might be a v6, and we can do the R-V/Ack the right way
>> at that time. No big deal, but it's good to know in one place as it
>> is a bit scatter here and there in the kernel-doc.
>>
>> [1] https://gitlab.freedesktop.org/drm/maintainer-tools/
>> [2] git am --message-id
>> [3] https://docs.kernel.org/maintainer/
>> -- 
>> Regards,
>> Luben
>>
> 
> Again thanks for all the details of the development flow. Will read up
> on all of this.
> 
> Just to be to clear, when I post a rev6 I should not include a RB in the
> patches that recieved an RB in rev5 (or prior revs)? Rather a Cc would
> be better to alert the reviewer of another rev?

If you've received an R-B in an email and are subsequently reposting
the patch, append the R-B at the bottom of the tags, as a tool would do it.

As for Cc: tags, I never separate --to/--cc/Cc:. I just include everyone
in a Cc: tag, and my --to is just amdgfx or dri-dev. This way I don't need
to worry about cc-s and what not--it's all in the commit message. It makes
it easy for me, but you can do it whichever way is easier for you.

As to Cc field, if I want someone to see my email, I always Cc them, else the rules
put the email in some folder, where it may not be seen. But if their email
is in the Cc or To field, then I know they'll get it in their inbox.
-- 
Regards,
Luben

Re: [PATCH v5 5/7] drm/sched: Split free_job into own work item

[Luben Tuikov]

On 2023-10-16 11:12, Matthew Brost wrote:
> On Sat, Oct 14, 2023 at 08:09:31PM -0400, Luben Tuikov wrote:
>> On 2023-10-13 22:49, Luben Tuikov wrote:
>>> On 2023-10-11 19:58, Matthew Brost wrote:
>>>> Rather than call free_job and run_job in same work item have a dedicated
>>>> work item for each. This aligns with the design and intended use of work
>>>> queues.
>>>>
>>>> v2:
>>>>    - Test for DMA_FENCE_FLAG_TIMESTAMP_BIT before setting
>>>>      timestamp in free_job() work item (Danilo)
>>>> v3:
>>>>   - Drop forward dec of drm_sched_select_entity (Boris)
>>>>   - Return in drm_sched_run_job_work if entity NULL (Boris)
>>>> v4:
>>>>   - Replace dequeue with peek and invert logic (Luben)
>>>>   - Wrap to 100 lines (Luben)
>>>>   - Update comments for *_queue / *_queue_if_ready functions (Luben)
>>>>
>>>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
>>>
>>> I wasn't able to apply this patch on top of drm-misc-next at a48e2cc92835fa.
>>>
>>> Create a branch off of a *clean* drm-misc-next and rebase/reapply/cherry-pick all
>>> 7 patches on top of that clean drm-misc-next branch. You should also run
>>> scripts/checkpatch.pl --strict on all your patches, or integrate it into the precommit
>>> hook, see githooks(5), so you don't have to run it manually.
>>>
>>> Set format.useAutobase to whenAble somewhere in your Git configs (global/local),
>>> or use --base=auto to git-format-patch when you format your patches before
>>> git-send-email-ing them.
>>>
>>> Repost your patches.
>>>
>>> The base commit will be added to the bottom of the cover letter. It should
>>> be an ancestor (or tip) of drm-misc-next (git branch --contains <base> --list etc.).
>>> If it is not, your base tree wasn't clean, and you should redo this process.
>>
>> Poking around I found out that this patch set is based off of drm-misc-fixes.
>> Had the base been included, it would've made this easier.
> 
> I believe I based this off of drm-tip. Will follow the flow mentioned above in next rev.

Sure. You can use drm-tip, drm-misc-next, drm-misc-fixes, just make sure --base=auto
is set as outlined above, and if you're including a cover letter (a free format text),
you can mention the base branch in there too, even though useAutobase has included the SHA,
it makes it easier.
-- 
Regards,
Luben

Re: [PATCH v5 5/7] drm/sched: Split free_job into own work item

[Luben Tuikov]

On 2023-10-16 11:29, Luben Tuikov wrote:
> On 2023-10-16 11:12, Matthew Brost wrote:
>> On Sat, Oct 14, 2023 at 08:09:31PM -0400, Luben Tuikov wrote:
>>> On 2023-10-13 22:49, Luben Tuikov wrote:
>>>> On 2023-10-11 19:58, Matthew Brost wrote:
>>>>> Rather than call free_job and run_job in same work item have a dedicated
>>>>> work item for each. This aligns with the design and intended use of work
>>>>> queues.
>>>>>
>>>>> v2:
>>>>>    - Test for DMA_FENCE_FLAG_TIMESTAMP_BIT before setting
>>>>>      timestamp in free_job() work item (Danilo)
>>>>> v3:
>>>>>   - Drop forward dec of drm_sched_select_entity (Boris)
>>>>>   - Return in drm_sched_run_job_work if entity NULL (Boris)
>>>>> v4:
>>>>>   - Replace dequeue with peek and invert logic (Luben)
>>>>>   - Wrap to 100 lines (Luben)
>>>>>   - Update comments for *_queue / *_queue_if_ready functions (Luben)
>>>>>
>>>>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
>>>>
>>>> I wasn't able to apply this patch on top of drm-misc-next at a48e2cc92835fa.
>>>>
>>>> Create a branch off of a *clean* drm-misc-next and rebase/reapply/cherry-pick all
>>>> 7 patches on top of that clean drm-misc-next branch. You should also run
>>>> scripts/checkpatch.pl --strict on all your patches, or integrate it into the precommit
>>>> hook, see githooks(5), so you don't have to run it manually.
>>>>
>>>> Set format.useAutobase to whenAble somewhere in your Git configs (global/local),
>>>> or use --base=auto to git-format-patch when you format your patches before
>>>> git-send-email-ing them.
>>>>
>>>> Repost your patches.
>>>>
>>>> The base commit will be added to the bottom of the cover letter. It should
>>>> be an ancestor (or tip) of drm-misc-next (git branch --contains <base> --list etc.).
>>>> If it is not, your base tree wasn't clean, and you should redo this process.
>>>
>>> Poking around I found out that this patch set is based off of drm-misc-fixes.
>>> Had the base been included, it would've made this easier.
>>
>> I believe I based this off of drm-tip. Will follow the flow mentioned above in next rev.
> 
> Sure. You can use drm-tip, drm-misc-next, drm-misc-fixes, just make sure --base=auto
> is set as outlined above, and if you're including a cover letter (a free format text),
> you can mention the base branch in there too, even though useAutobase has included the SHA,
> it makes it easier.

Using -fixes or -tip is better as it includes Christian's dma_fence_timestamp() helper, and we want that in.
-- 
Regards,
Luben

Re: [PATCH v5 3/7] drm/sched: Move schedule policy to scheduler

[Luben Tuikov]

One more very important thing!

Once you add an R-V tag, you cannot change the patch and keep the R-V, when reposting it.

If you change the code and thus the patch changes, you _*must*_ remove the R-V tag,
to let people know that there's changes which need reviewing.

Regards,
Luben

On 2023-10-12 01:54, Luben Tuikov wrote:
> On 2023-10-12 00:31, Matthew Brost wrote:
>> On Wed, Oct 11, 2023 at 08:39:55PM -0400, Luben Tuikov wrote:
>>> On 2023-10-11 19:58, Matthew Brost wrote:
>>>> Rather than a global modparam for scheduling policy, move the scheduling
>>>> policy to scheduler so user can control each scheduler policy.
>>>>
>>>> v2:
>>>>   - s/DRM_SCHED_POLICY_MAX/DRM_SCHED_POLICY_COUNT (Luben)
>>>>   - Only include policy in scheduler (Luben)
>>>> v3:
>>>>   - use a ternary operator as opposed to an if-control (Luben)
>>>>   - s/DRM_SCHED_POLICY_DEFAULT/DRM_SCHED_POLICY_UNSET/ (Luben)
>>>>   - s/default_drm_sched_policy/drm_sched_policy_default/ (Luben)
>>>>   - Update commit message (Boris)
>>>>   - Fix v3d build (CI)
>>>>   - s/bad_policies/drm_sched_policy_mismatch/ (Luben)
>>>>   - Don't update modparam doc (Luben)
>>>> v4:
>>>>   - Fix alignment in msm_ringbuffer_new (Luben / checkpatch)
>>>>
>>>> Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
>>>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
>>>
>>> Was the R-V added by hand? (As in editing the commit message manually?)
>>>
>>
>> Yes.
>>
>>> I use automated tools for this which do not re-order the tags.
>>> IOW, the S-O-B is first as this is how it appears in the patch,
>>> then the R-V most probably added by automated tools, and then
>>> any other as are tacked on by other automated tools.
>>>
>>
>> Ok, so always add tags in order starting with S-O-B?
> 
> Yes!
> 
> The S-O-B tag you add when you write the commit and then you post
> it up to a mailing list, it's mandatory and it's always there.
> It's most likely the first, top tag.
> 
> Then various other scripts and tools start adding tags in an automated way,
> and those tags are just appended below any existing tags.
> 
> Generally, always follow a natural order (meaning least amount of energy
> expenditure--if you have to edit to reorder, that is extra energy expenditure
> and nature doesn't like that). Make it like a letter you'd get from or write to
> your bank, attorney, etc.
> 	These are tags you add when you craft your commit:
> Cc: goes first, followed by other tags whose values
> Cc: are personal emails, i.e. people. These are people
> Cc: you want to let know of this commit. This is followed
> Cc: by other personal tags, for instance,
> Co-developed-by: or
> Suggested-by: Another personal tag is,
> Reported-by: which must be followed by a Link tag with
> Link: the link of the report. This could also be a link to anything else. You can also add a
> Fixes: tag which should follow a --pretty %h (\"%s\") format.
> Closes: link to the bug the patch closes
> Signed-off-by: You
> 	Then scripts and tools (or even people) would append the tag list with:
> Tested-by: someone reliable, could have more than one instance of this tag,
> Acked-by: someone
> Reviewed-by: someone
> 
> There are no empty lines between tags. They form a block paragraph as they would
> if/when added by a script. (I never add _any_ tag manually.)
> 
> So, for instance, you may have:
> 
> Cc: Luben
> Signed-off-by: Matt
> 
> And when the patch is R-V-ed this becomes (least amount of energy, append at the bottom),
> 
> Cc: Luben
> Signed-off-by: Matt
> Reviewed-by: Luben
> 
> Then other tags may be appended, depending on the path the patch takes to land in a tree.
> 
> Check out:
> https://docs.kernel.org/process/5.Posting.html
> https://docs.kernel.org/process/submitting-patches.html
> https://docs.kernel.org/process/submit-checklist.html
> And there's more resources to check out in the Documentation/process directory.