[PATCH 1/6] amd/scheduler:imple job skip feature(v3)

[Monk Liu]

jobs are skipped under two cases
1)when the entity behind this job marked guilty, the job
poped from this entity's queue will be dropped in sched_main loop.

2)in job_recovery(), skip the scheduling job if its karma detected
above limit, and also skipped as well for other jobs sharing the
same fence context. this approach is becuase job_recovery() cannot
access job->entity due to entity may already dead.

v2:
some logic fix

v3:
when entity detected guilty, don't drop the job in the poping
stage, instead set its fence error as -ECANCELED

in run_job(), skip the scheduling either:1) fence->error < 0
or 2) there was a VRAM LOST occurred on this job.
this way we can unify the job skipping logic.

with this feature we can introduce new gpu recover feature.

Change-Id: I268b1c752c94e6ecd4ea78c87eb226ea3f52908a
Signed-off-by: Monk Liu <Monk.Liu at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_job.c       | 13 +++++----
 drivers/gpu/drm/amd/scheduler/gpu_scheduler.c | 39 ++++++++++++++++-----------
 2 files changed, 31 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
index f60662e..0a90c76 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
@@ -180,7 +180,7 @@ static struct dma_fence *amdgpu_job_dependency(struct amd_sched_job *sched_job,
 
 static struct dma_fence *amdgpu_job_run(struct amd_sched_job *sched_job)
 {
-	struct dma_fence *fence = NULL;
+	struct dma_fence *fence = NULL, *finished;
 	struct amdgpu_device *adev;
 	struct amdgpu_job *job;
 	int r;
@@ -190,15 +190,18 @@ static struct dma_fence *amdgpu_job_run(struct amd_sched_job *sched_job)
 		return NULL;
 	}
 	job = to_amdgpu_job(sched_job);
+	finished = &job->base.s_fence->finished;
 	adev = job->adev;
 
 	BUG_ON(amdgpu_sync_peek_fence(&job->sync, NULL));
 
 	trace_amdgpu_sched_run_job(job);
-	/* skip ib schedule when vram is lost */
-	if (job->vram_lost_counter != atomic_read(&adev->vram_lost_counter)) {
-		dma_fence_set_error(&job->base.s_fence->finished, -ECANCELED);
-		DRM_ERROR("Skip scheduling IBs!\n");
+
+	if (job->vram_lost_counter != atomic_read(&adev->vram_lost_counter))
+		dma_fence_set_error(finished, -ECANCELED);/* skip IB as well if VRAM lost */
+
+	if (finished->error < 0) {
+		DRM_INFO("Skip scheduling IBs!\n");
 	} else {
 		r = amdgpu_ib_schedule(job->ring, job->num_ibs, job->ibs, job,
 				       &fence);
diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
index 903ef8b..3d8c994 100644
--- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
+++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
@@ -344,6 +344,10 @@ amd_sched_entity_pop_job(struct amd_sched_entity *entity)
 		if (amd_sched_entity_add_dependency_cb(entity))
 			return NULL;
 
+	/* skip jobs from entity that marked guilty */
+	if (entity->guilty && atomic_read(entity->guilty))
+		dma_fence_set_error(&sched_job->s_fence->finished, -ECANCELED);
+
 	spsc_queue_pop(&entity->job_queue);
 	return sched_job;
 }
@@ -440,14 +444,6 @@ static void amd_sched_job_timedout(struct work_struct *work)
 	job->sched->ops->timedout_job(job);
 }
 
-static void amd_sched_set_guilty(struct amd_sched_job *s_job,
-				 struct amd_sched_entity *s_entity)
-{
-	if (atomic_inc_return(&s_job->karma) > s_job->sched->hang_limit)
-		if (s_entity->guilty)
-			atomic_set(s_entity->guilty, 1);
-}
-
 void amd_sched_hw_job_reset(struct amd_gpu_scheduler *sched, struct amd_sched_job *bad)
 {
 	struct amd_sched_job *s_job;
@@ -467,21 +463,24 @@ void amd_sched_hw_job_reset(struct amd_gpu_scheduler *sched, struct amd_sched_jo
 	spin_unlock(&sched->job_list_lock);
 
 	if (bad) {
-		bool found = false;
-
-		for (i = AMD_SCHED_PRIORITY_MIN; i < AMD_SCHED_PRIORITY_MAX; i++ ) {
+		/* don't increase @bad's karma if it's from KERNEL RQ,
+		 * becuase sometimes GPU hang would cause kernel jobs (like VM updating jobs)
+		 * corrupt but keep in mind that kernel jobs always considered good.
+		 */
+		for (i = AMD_SCHED_PRIORITY_MIN; i < AMD_SCHED_PRIORITY_KERNEL; i++ ) {
 			struct amd_sched_rq *rq = &sched->sched_rq[i];
 
 			spin_lock(&rq->lock);
 			list_for_each_entry_safe(entity, tmp, &rq->entities, list) {
 				if (bad->s_fence->scheduled.context == entity->fence_context) {
-					found = true;
-					amd_sched_set_guilty(bad, entity);
+				    if (atomic_inc_return(&bad->karma) > bad->sched->hang_limit)
+						if (entity->guilty)
+							atomic_set(entity->guilty, 1);
 					break;
 				}
 			}
 			spin_unlock(&rq->lock);
-			if (found)
+			if (&entity->list == &rq->entities)
 				break;
 		}
 	}
@@ -499,6 +498,7 @@ void amd_sched_job_kickout(struct amd_sched_job *s_job)
 void amd_sched_job_recovery(struct amd_gpu_scheduler *sched)
 {
 	struct amd_sched_job *s_job, *tmp;
+	bool found_guilty = false;
 	int r;
 
 	spin_lock(&sched->job_list_lock);
@@ -510,6 +510,15 @@ void amd_sched_job_recovery(struct amd_gpu_scheduler *sched)
 	list_for_each_entry_safe(s_job, tmp, &sched->ring_mirror_list, node) {
 		struct amd_sched_fence *s_fence = s_job->s_fence;
 		struct dma_fence *fence;
+		uint64_t guilty_context;
+
+		if (!found_guilty && atomic_read(&s_job->karma) > sched->hang_limit) {
+			found_guilty = true;
+			guilty_context = s_job->s_fence->scheduled.context;
+		}
+
+		if (found_guilty && s_job->s_fence->scheduled.context == guilty_context)
+			dma_fence_set_error(&s_fence->finished, -ECANCELED);
 
 		spin_unlock(&sched->job_list_lock);
 		fence = sched->ops->run_job(s_job);
@@ -525,7 +534,6 @@ void amd_sched_job_recovery(struct amd_gpu_scheduler *sched)
 					  r);
 			dma_fence_put(fence);
 		} else {
-			DRM_ERROR("Failed to run job!\n");
 			amd_sched_process_job(NULL, &s_fence->cb);
 		}
 		spin_lock(&sched->job_list_lock);
@@ -663,7 +671,6 @@ static int amd_sched_main(void *param)
 					  r);
 			dma_fence_put(fence);
 		} else {
-			DRM_ERROR("Failed to run job!\n");
 			amd_sched_process_job(NULL, &s_fence->cb);
 		}
 
-- 
2.7.4