diff mbox series

[4/8] drm/sched: Optimise drm_sched_entity_push_job

Message ID 20240909171937.51550-5-tursulin@igalia.com (mailing list archive)
State New, archived
Headers show
Series DRM scheduler fixes, or not, or incorrect kind | expand

Commit Message

Tvrtko Ursulin Sept. 9, 2024, 5:19 p.m. UTC 
From: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>

In FIFO mode We can avoid dropping the lock only to immediately re-acquire
by adding a new drm_sched_rq_update_fifo_locked() helper.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Luben Tuikov <ltuikov89@gmail.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Philipp Stanner <pstanner@redhat.com>
---
 drivers/gpu/drm/scheduler/sched_entity.c |  5 +++--
 drivers/gpu/drm/scheduler/sched_main.c   | 21 ++++++++++++++-------
 include/drm/gpu_scheduler.h              |  1 +
 3 files changed, 18 insertions(+), 9 deletions(-)

Comments

Christian König Sept. 10, 2024, 8:36 a.m. UTC | #1 
Am 09.09.24 um 19:19 schrieb Tvrtko Ursulin:
> From: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
>
> In FIFO mode We can avoid dropping the lock only to immediately re-acquire
> by adding a new drm_sched_rq_update_fifo_locked() helper.
>
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
> Cc: Christian König <christian.koenig@amd.com>
> Cc: Alex Deucher <alexander.deucher@amd.com>
> Cc: Luben Tuikov <ltuikov89@gmail.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: Philipp Stanner <pstanner@redhat.com>
> ---
>   drivers/gpu/drm/scheduler/sched_entity.c |  5 +++--
>   drivers/gpu/drm/scheduler/sched_main.c   | 21 ++++++++++++++-------
>   include/drm/gpu_scheduler.h              |  1 +
>   3 files changed, 18 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index 6645a8524699..2da677681291 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -615,10 +615,11 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
>   
>   		atomic_inc(sched->score);
>   		drm_sched_rq_add_entity(rq, entity);
> -		spin_unlock(&entity->rq_lock);
>   
>   		if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
> -			drm_sched_rq_update_fifo(entity, submit_ts);
> +			drm_sched_rq_update_fifo_locked(entity, submit_ts);
> +
> +		spin_unlock(&entity->rq_lock);
>   
>   		drm_sched_wakeup(sched, entity);
>   	}
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index ab53ab486fe6..10abbcefe9d8 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -163,14 +163,10 @@ 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)
> +void drm_sched_rq_update_fifo_locked(struct drm_sched_entity *entity, ktime_t ts)
>   {
> -	/*
> -	 * 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
> -	 * other to update the rb tree structure.
> -	 */
> -	spin_lock(&entity->rq_lock);
> +	lockdep_assert_held(&entity->rq_lock);
> +
>   	spin_lock(&entity->rq->lock);
>   
>   	drm_sched_rq_remove_fifo_locked(entity);
> @@ -181,6 +177,17 @@ void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
>   		      drm_sched_entity_compare_before);
>   
>   	spin_unlock(&entity->rq->lock);
> +}
> +
> +void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
> +{
> +	/*
> +	 * 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
> +	 * other to update the rb tree structure.
> +	 */
> +	spin_lock(&entity->rq_lock);
> +	drm_sched_rq_update_fifo_locked(entity, ts);
>   	spin_unlock(&entity->rq_lock);
>   }

I wonder if we shouldn't change the only other occasion calling this to 
grab the lock manually as well.

Christian.

>   
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index fe8edb917360..a06753987d93 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -594,6 +594,7 @@ void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
>   				struct drm_sched_entity *entity);
>   
>   void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts);
> +void drm_sched_rq_update_fifo_locked(struct drm_sched_entity *entity, ktime_t ts);
>   
>   int drm_sched_entity_init(struct drm_sched_entity *entity,
>   			  enum drm_sched_priority priority,
diff mbox series

Patch

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index 6645a8524699..2da677681291 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -615,10 +615,11 @@  void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
 
 		atomic_inc(sched->score);
 		drm_sched_rq_add_entity(rq, entity);
-		spin_unlock(&entity->rq_lock);
 
 		if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
-			drm_sched_rq_update_fifo(entity, submit_ts);
+			drm_sched_rq_update_fifo_locked(entity, submit_ts);
+
+		spin_unlock(&entity->rq_lock);
 
 		drm_sched_wakeup(sched, entity);
 	}
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index ab53ab486fe6..10abbcefe9d8 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -163,14 +163,10 @@  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)
+void drm_sched_rq_update_fifo_locked(struct drm_sched_entity *entity, ktime_t ts)
 {
-	/*
-	 * 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
-	 * other to update the rb tree structure.
-	 */
-	spin_lock(&entity->rq_lock);
+	lockdep_assert_held(&entity->rq_lock);
+
 	spin_lock(&entity->rq->lock);
 
 	drm_sched_rq_remove_fifo_locked(entity);
@@ -181,6 +177,17 @@  void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
 		      drm_sched_entity_compare_before);
 
 	spin_unlock(&entity->rq->lock);
+}
+
+void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts)
+{
+	/*
+	 * 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
+	 * other to update the rb tree structure.
+	 */
+	spin_lock(&entity->rq_lock);
+	drm_sched_rq_update_fifo_locked(entity, ts);
 	spin_unlock(&entity->rq_lock);
 }
 
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index fe8edb917360..a06753987d93 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -594,6 +594,7 @@  void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
 				struct drm_sched_entity *entity);
 
 void drm_sched_rq_update_fifo(struct drm_sched_entity *entity, ktime_t ts);
+void drm_sched_rq_update_fifo_locked(struct drm_sched_entity *entity, ktime_t ts);
 
 int drm_sched_entity_init(struct drm_sched_entity *entity,
 			  enum drm_sched_priority priority,