[PATCH v3 0/3] drm/sched: Introduce more locking to entity

[PATCH v3 0/3] drm/sched: Introduce more locking to entity

[Philipp Stanner]

Changes since v2:
  - Fix ordering bug between spsc_queue_pop() and
    drm_sched_rq_pop_entity().

Changes since v1:
  - Remove a bunch of patches; make this series only about locking
    entity->last_scheduled. The rest shall be done in separate patches
    and series. Consequently, also do not lock spsc_queue, yet.
  - Move lock-cycle patch to first position. (Tvrtko)


Both Tvrtko [1] and I [2] have recently proposed some improvals for
drm_sched.

While taking Tvrtko's feedback into account for my patch, I realized
that both his and my patch can be fully replaced with a bigger and far
more beautiful series.

If I am not mistaken, it turns out that the entire entity->entity_idle
completion is also nothing but a workaround around the grave mistake of
not using the greatest helper with parallel programming that exists in
computer science: Locking.

This series adds locking to the last_scheduled field and all checks
related to detect the idleness of the entity. As before, the
job_scheduled event queue causes the periodic checks.

This way, we can get rid of memory barriers, RCU, a few lines of code,
make things more readable, understandable...

Greetings,
Philipp

[1] https://lore.kernel.org/dri-devel/20260611123423.39819-1-tvrtko.ursulin@igalia.com/
[2] https://lore.kernel.org/dri-devel/20260626081942.2122144-2-phasta@kernel.org/

Philipp Stanner (3):
  drm/sched: Lock drm_sched_rq_pop_entity() externally
  drm/sched: Lock spsc_queue_pop() in drm_sched_entity_pop_job()
  drm/sched: Protect entity->last_scheduled with spinlock

 drivers/gpu/drm/scheduler/sched_entity.c | 53 ++++++++++--------------
 drivers/gpu/drm/scheduler/sched_rq.c     |  4 +-
 include/drm/gpu_scheduler.h              | 10 ++---
 3 files changed, 28 insertions(+), 39 deletions(-)

-- 
2.55.0

[PATCH v3 1/3] drm/sched: Lock drm_sched_rq_pop_entity() externally

[Philipp Stanner]

In order to protect entity->last_scheduled with a spinlock, adding
locking to drm_sched_entity_pop_job() is necessary. This would lead to a
slightly suboptimal lock-unlock-relock pattern with
drm_sched_rq_pop_entity().

As a preparational step for adding the locking, lock
drm_sched_rq_pop_entity() externally.

Signed-off-by: Philipp Stanner <phasta@kernel.org>
---
 drivers/gpu/drm/scheduler/sched_entity.c | 2 ++
 drivers/gpu/drm/scheduler/sched_rq.c     | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index bf97508a45b9..274d7a702298 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -565,7 +565,9 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
 
 	spsc_queue_pop(&entity->job_queue);
 
+	spin_lock(&entity->lock);
 	drm_sched_rq_pop_entity(entity);
+	spin_unlock(&entity->lock);
 
 	/* Jobs and entities might have different lifecycles. Since we're
 	 * removing the job from the entities queue, set the jobs entity pointer
diff --git a/drivers/gpu/drm/scheduler/sched_rq.c b/drivers/gpu/drm/scheduler/sched_rq.c
index 0464d324d98d..696792a18708 100644
--- a/drivers/gpu/drm/scheduler/sched_rq.c
+++ b/drivers/gpu/drm/scheduler/sched_rq.c
@@ -346,11 +346,12 @@ void drm_sched_rq_pop_entity(struct drm_sched_entity *entity)
 	struct drm_sched_job *next_job;
 	struct drm_sched_rq *rq;
 
+	lockdep_assert_held(&entity->lock);
+
 	/*
 	 * Update the entity's location in the min heap according to
 	 * the timestamp of the next job, if any.
 	 */
-	spin_lock(&entity->lock);
 	rq = entity->rq;
 	spin_lock(&rq->lock);
 	next_job = drm_sched_entity_queue_peek(entity);
@@ -376,7 +377,6 @@ void drm_sched_rq_pop_entity(struct drm_sched_entity *entity)
 		}
 	}
 	spin_unlock(&rq->lock);
-	spin_unlock(&entity->lock);
 }
 
 /**
-- 
2.55.0

[PATCH v3 2/3] drm/sched: Lock spsc_queue_pop() in drm_sched_entity_pop_job()

[Philipp Stanner]

As a preparational step to lock the access of entity->last_scheduled, it
is necessary to lock the call to spsc_queue_pop() in
drm_sched_entity_pop_job(). The reason is that later the existing lock
needs to be moved upward and the relative order between spsc_queue_pop()
and drm_sched_rq_pop_entity() needs to be preserved.

Guard spsc_queue_pop() with the existing spinlock.

Signed-off-by: Philipp Stanner <phasta@kernel.org>
---
 drivers/gpu/drm/scheduler/sched_entity.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index 274d7a702298..e168f445f2ab 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -563,9 +563,8 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
 	 */
 	smp_wmb();
 
-	spsc_queue_pop(&entity->job_queue);
-
 	spin_lock(&entity->lock);
+	spsc_queue_pop(&entity->job_queue);
 	drm_sched_rq_pop_entity(entity);
 	spin_unlock(&entity->lock);
 
-- 
2.55.0

[PATCH v3 3/3] drm/sched: Protect entity->last_scheduled with spinlock

[Philipp Stanner]

The entity->last_scheduled field has always been set and read with
special RCU functions in addition to memory barriers.

This was added in

commit 70102d77ff22 ("drm/scheduler: add drm_sched_entity_error and use rcu for last_scheduled")

however, no proper justification for that mechanism was provided. There
seems to be no obvious reason, since the entity lock is available and
taken at all places that evaluate the last_scheduled field. The only
exception is drm_sched_entity_error(), which is not performance critical
in any way.

Improve robustness, readability and maintainability by replacing RCU and
barriers with the lock.

Signed-off-by: Philipp Stanner <phasta@kernel.org>
---
 drivers/gpu/drm/scheduler/sched_entity.c | 50 ++++++++++--------------
 include/drm/gpu_scheduler.h              | 10 ++---
 2 files changed, 24 insertions(+), 36 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index e168f445f2ab..fa4a9388e5c9 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -136,7 +136,6 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
 			      DRM_SCHED_PRIORITY_KERNEL : priority;
 	entity->num_sched_list = num_sched_list;
 	entity->sched_list = num_sched_list > 1 ? sched_list : NULL;
-	RCU_INIT_POINTER(entity->last_scheduled, NULL);
 	RB_CLEAR_NODE(&entity->rb_tree_node);
 
 	if (!sched_list[0]->sched_rq) {
@@ -233,10 +232,10 @@ int drm_sched_entity_error(struct drm_sched_entity *entity)
 	struct dma_fence *fence;
 	int r;
 
-	rcu_read_lock();
-	fence = rcu_dereference(entity->last_scheduled);
+	spin_lock(&entity->lock);
+	fence = entity->last_scheduled;
 	r = fence ? fence->error : 0;
-	rcu_read_unlock();
+	spin_unlock(&entity->lock);
 
 	return r;
 }
@@ -319,9 +318,10 @@ void drm_sched_entity_kill(struct drm_sched_entity *entity)
 	/* Make sure this entity is not used by the scheduler at the moment */
 	wait_for_completion(&entity->entity_idle);
 
-	/* The entity is guaranteed to not be used by the scheduler */
-	prev = rcu_dereference_check(entity->last_scheduled, true);
+	spin_lock(&entity->lock);
+	prev = entity->last_scheduled;
 	dma_fence_get(prev);
+	spin_unlock(&entity->lock);
 	while ((job = drm_sched_entity_queue_pop(entity))) {
 		struct drm_sched_fence *s_fence = job->s_fence;
 
@@ -413,8 +413,7 @@ void drm_sched_entity_fini(struct drm_sched_entity *entity)
 		entity->dependency = NULL;
 	}
 
-	dma_fence_put(rcu_dereference_check(entity->last_scheduled, true));
-	RCU_INIT_POINTER(entity->last_scheduled, NULL);
+	dma_fence_put(entity->last_scheduled);
 	drm_sched_entity_stats_put(entity->stats);
 }
 EXPORT_SYMBOL(drm_sched_entity_fini);
@@ -536,6 +535,10 @@ drm_sched_job_dependency(struct drm_sched_job *job,
 
 struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
 {
+	/* Helper to avoid dropping the reference while the entity lock is held,
+	 * just to have some more robustness.
+	 */
+	struct dma_fence *prev_last_scheduled;
 	struct drm_sched_job *sched_job;
 
 	sched_job = drm_sched_entity_queue_peek(entity);
@@ -552,22 +555,15 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
 	if (entity->guilty && atomic_read(entity->guilty))
 		dma_fence_set_error(&sched_job->s_fence->finished, -ECANCELED);
 
-	dma_fence_put(rcu_dereference_check(entity->last_scheduled, true));
-	rcu_assign_pointer(entity->last_scheduled,
-			   dma_fence_get(&sched_job->s_fence->finished));
-
-	/*
-	 * If the queue is empty we allow drm_sched_entity_select_rq() to
-	 * locklessly access ->last_scheduled. This only works if we set the
-	 * pointer before we dequeue and if we a write barrier here.
-	 */
-	smp_wmb();
-
 	spin_lock(&entity->lock);
+	prev_last_scheduled = entity->last_scheduled;
+	entity->last_scheduled = dma_fence_get(&sched_job->s_fence->finished);
 	spsc_queue_pop(&entity->job_queue);
 	drm_sched_rq_pop_entity(entity);
 	spin_unlock(&entity->lock);
 
+	dma_fence_put(prev_last_scheduled);
+
 	/* Jobs and entities might have different lifecycles. Since we're
 	 * removing the job from the entities queue, set the jobs entity pointer
 	 * to NULL to prevent any future access of the entity through this job.
@@ -591,21 +587,15 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
 	if (spsc_queue_count(&entity->job_queue))
 		return;
 
-	/*
-	 * Only when the queue is empty are we guaranteed that
-	 * drm_sched_run_job_work() cannot change entity->last_scheduled. To
-	 * enforce ordering we need a read barrier here. See
-	 * drm_sched_entity_pop_job() for the other side.
-	 */
-	smp_rmb();
-
-	fence = rcu_dereference_check(entity->last_scheduled, true);
+	spin_lock(&entity->lock);
+	fence = entity->last_scheduled;
 
 	/* stay on the same engine if the previous job hasn't finished */
-	if (fence && !dma_fence_is_signaled(fence))
+	if (fence && !dma_fence_is_signaled(fence)) {
+		spin_unlock(&entity->lock);
 		return;
+	}
 
-	spin_lock(&entity->lock);
 	sched = drm_sched_pick_best(entity->sched_list, entity->num_sched_list);
 	rq = sched ? sched->sched_rq[entity->rq_priority] : NULL;
 	if (rq != entity->rq) {
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 7a64cc11de08..aeeea6efc623 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -100,8 +100,8 @@ struct drm_sched_entity {
 	 * @lock:
 	 *
 	 * Lock protecting the run-queue (@rq) to which this entity belongs,
-	 * @priority, the list of schedulers (@sched_list, @num_sched_list) and
-	 * the @rr_ts field.
+	 * @priority, @last_scheduled and the list of schedulers (@sched_list,
+	 * @num_sched_list).
 	 */
 	spinlock_t			lock;
 
@@ -215,11 +215,9 @@ struct drm_sched_entity {
 	/**
 	 * @last_scheduled:
 	 *
-	 * Points to the finished fence of the last scheduled job. Only written
-	 * by drm_sched_entity_pop_job(). Can be accessed locklessly from
-	 * drm_sched_job_arm() if the queue is empty.
+	 * Points to the finished fence of the last scheduled job.
 	 */
-	struct dma_fence __rcu		*last_scheduled;
+	struct dma_fence		*last_scheduled;
 
 	/**
 	 * @last_user: last group leader pushing a job into the entity.
-- 
2.55.0

Re: [PATCH v3 3/3] drm/sched: Protect entity->last_scheduled with spinlock

[Tvrtko Ursulin]

+ Christian's e-mail which he reads :)

On 10/09/2026 08:59, Philipp Stanner wrote:
> The entity->last_scheduled field has always been set and read with
> special RCU functions in addition to memory barriers.
> 
> This was added in
> 
> commit 70102d77ff22 ("drm/scheduler: add drm_sched_entity_error and use rcu for last_scheduled")
> 
> however, no proper justification for that mechanism was provided. There
> seems to be no obvious reason, since the entity lock is available and
> taken at all places that evaluate the last_scheduled field. The only
> exception is drm_sched_entity_error(), which is not performance critical
> in any way.

FWIW the entry paths that I found from the amdgpu side are from the job 
submission side where it is called a few times for each job via 
amdgpu_ctx_get_entity(), amdgpu_job_prepare_job() and 
amdgpu_vm_generation(). Last one being both in amdgpu_job_alloc() and 
amdgpu_job_run(). If I did not miss any, the change effectively adds 
four lock-unlock cycles to the job submission path. Plus one more for 
schedulers which use load balancing in some cases.

I don't know if avoiding that was the reason RCU was chosen, perhaps 
Christian remembers.

Also, to repeat what I said before, I benchmarked this a bit under 
extreme circumstances (4x non vsynced vkgears) and did not find a 
regression in fps.

> Improve robustness, readability and maintainability by replacing RCU and
> barriers with the lock.
> 
> Signed-off-by: Philipp Stanner <phasta@kernel.org>
> ---
>   drivers/gpu/drm/scheduler/sched_entity.c | 50 ++++++++++--------------
>   include/drm/gpu_scheduler.h              | 10 ++---
>   2 files changed, 24 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index e168f445f2ab..fa4a9388e5c9 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -136,7 +136,6 @@ int drm_sched_entity_init(struct drm_sched_entity *entity,
>   			      DRM_SCHED_PRIORITY_KERNEL : priority;
>   	entity->num_sched_list = num_sched_list;
>   	entity->sched_list = num_sched_list > 1 ? sched_list : NULL;
> -	RCU_INIT_POINTER(entity->last_scheduled, NULL);
>   	RB_CLEAR_NODE(&entity->rb_tree_node);
>   
>   	if (!sched_list[0]->sched_rq) {
> @@ -233,10 +232,10 @@ int drm_sched_entity_error(struct drm_sched_entity *entity)
>   	struct dma_fence *fence;
>   	int r;
>   
> -	rcu_read_lock();
> -	fence = rcu_dereference(entity->last_scheduled);
> +	spin_lock(&entity->lock);
> +	fence = entity->last_scheduled;
>   	r = fence ? fence->error : 0;
> -	rcu_read_unlock();
> +	spin_unlock(&entity->lock);
>   
>   	return r;
>   }
> @@ -319,9 +318,10 @@ void drm_sched_entity_kill(struct drm_sched_entity *entity)
>   	/* Make sure this entity is not used by the scheduler at the moment */
>   	wait_for_completion(&entity->entity_idle);
>   
> -	/* The entity is guaranteed to not be used by the scheduler */
> -	prev = rcu_dereference_check(entity->last_scheduled, true);
> +	spin_lock(&entity->lock);
> +	prev = entity->last_scheduled;
>   	dma_fence_get(prev);

Here you can compact with the idiomatic:

  prev = dma_fence_get(entity->last_scheduled);

Otherwise looks plausible to me. Lets see what sashiko will have to say 
this time round.

Regards,

Tvrtko

> +	spin_unlock(&entity->lock);
>   	while ((job = drm_sched_entity_queue_pop(entity))) {
>   		struct drm_sched_fence *s_fence = job->s_fence;
>   
> @@ -413,8 +413,7 @@ void drm_sched_entity_fini(struct drm_sched_entity *entity)
>   		entity->dependency = NULL;
>   	}
>   
> -	dma_fence_put(rcu_dereference_check(entity->last_scheduled, true));
> -	RCU_INIT_POINTER(entity->last_scheduled, NULL);
> +	dma_fence_put(entity->last_scheduled);
>   	drm_sched_entity_stats_put(entity->stats);
>   }
>   EXPORT_SYMBOL(drm_sched_entity_fini);
> @@ -536,6 +535,10 @@ drm_sched_job_dependency(struct drm_sched_job *job,
>   
>   struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>   {
> +	/* Helper to avoid dropping the reference while the entity lock is held,
> +	 * just to have some more robustness.
> +	 */
> +	struct dma_fence *prev_last_scheduled;
>   	struct drm_sched_job *sched_job;
>   
>   	sched_job = drm_sched_entity_queue_peek(entity);
> @@ -552,22 +555,15 @@ struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
>   	if (entity->guilty && atomic_read(entity->guilty))
>   		dma_fence_set_error(&sched_job->s_fence->finished, -ECANCELED);
>   
> -	dma_fence_put(rcu_dereference_check(entity->last_scheduled, true));
> -	rcu_assign_pointer(entity->last_scheduled,
> -			   dma_fence_get(&sched_job->s_fence->finished));
> -
> -	/*
> -	 * If the queue is empty we allow drm_sched_entity_select_rq() to
> -	 * locklessly access ->last_scheduled. This only works if we set the
> -	 * pointer before we dequeue and if we a write barrier here.
> -	 */
> -	smp_wmb();
> -
>   	spin_lock(&entity->lock);
> +	prev_last_scheduled = entity->last_scheduled;
> +	entity->last_scheduled = dma_fence_get(&sched_job->s_fence->finished);
>   	spsc_queue_pop(&entity->job_queue);
>   	drm_sched_rq_pop_entity(entity);
>   	spin_unlock(&entity->lock);
>   
> +	dma_fence_put(prev_last_scheduled);
> +
>   	/* Jobs and entities might have different lifecycles. Since we're
>   	 * removing the job from the entities queue, set the jobs entity pointer
>   	 * to NULL to prevent any future access of the entity through this job.
> @@ -591,21 +587,15 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
>   	if (spsc_queue_count(&entity->job_queue))
>   		return;
>   
> -	/*
> -	 * Only when the queue is empty are we guaranteed that
> -	 * drm_sched_run_job_work() cannot change entity->last_scheduled. To
> -	 * enforce ordering we need a read barrier here. See
> -	 * drm_sched_entity_pop_job() for the other side.
> -	 */
> -	smp_rmb();
> -
> -	fence = rcu_dereference_check(entity->last_scheduled, true);
> +	spin_lock(&entity->lock);
> +	fence = entity->last_scheduled;
>   
>   	/* stay on the same engine if the previous job hasn't finished */
> -	if (fence && !dma_fence_is_signaled(fence))
> +	if (fence && !dma_fence_is_signaled(fence)) {
> +		spin_unlock(&entity->lock);
>   		return;
> +	}
>   
> -	spin_lock(&entity->lock);
>   	sched = drm_sched_pick_best(entity->sched_list, entity->num_sched_list);
>   	rq = sched ? sched->sched_rq[entity->rq_priority] : NULL;
>   	if (rq != entity->rq) {
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index 7a64cc11de08..aeeea6efc623 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -100,8 +100,8 @@ struct drm_sched_entity {
>   	 * @lock:
>   	 *
>   	 * Lock protecting the run-queue (@rq) to which this entity belongs,
> -	 * @priority, the list of schedulers (@sched_list, @num_sched_list) and
> -	 * the @rr_ts field.
> +	 * @priority, @last_scheduled and the list of schedulers (@sched_list,
> +	 * @num_sched_list).
>   	 */
>   	spinlock_t			lock;
>   
> @@ -215,11 +215,9 @@ struct drm_sched_entity {
>   	/**
>   	 * @last_scheduled:
>   	 *
> -	 * Points to the finished fence of the last scheduled job. Only written
> -	 * by drm_sched_entity_pop_job(). Can be accessed locklessly from
> -	 * drm_sched_job_arm() if the queue is empty.
> +	 * Points to the finished fence of the last scheduled job.
>   	 */
> -	struct dma_fence __rcu		*last_scheduled;
> +	struct dma_fence		*last_scheduled;
>   
>   	/**
>   	 * @last_user: last group leader pushing a job into the entity.

Re: [PATCH v3 0/3] drm/sched: Introduce more locking to entity

[Tvrtko Ursulin]

On 10/09/2026 08:59, Philipp Stanner wrote:
> Changes since v2:
>    - Fix ordering bug between spsc_queue_pop() and
>      drm_sched_rq_pop_entity().
> 
> Changes since v1:
>    - Remove a bunch of patches; make this series only about locking
>      entity->last_scheduled. The rest shall be done in separate patches
>      and series. Consequently, also do not lock spsc_queue, yet.
>    - Move lock-cycle patch to first position. (Tvrtko)
> 
> 
> Both Tvrtko [1] and I [2] have recently proposed some improvals for
> drm_sched.
> 
> While taking Tvrtko's feedback into account for my patch, I realized
> that both his and my patch can be fully replaced with a bigger and far
> more beautiful series.
> 
> If I am not mistaken, it turns out that the entire entity->entity_idle
> completion is also nothing but a workaround around the grave mistake of
> not using the greatest helper with parallel programming that exists in
> computer science: Locking.
> 
> This series adds locking to the last_scheduled field and all checks
> related to detect the idleness of the entity. As before, the
> job_scheduled event queue causes the periodic checks.
> 
> This way, we can get rid of memory barriers, RCU, a few lines of code,
> make things more readable, understandable...
> 
> Greetings,
> Philipp
> 
> [1] https://lore.kernel.org/dri-devel/20260611123423.39819-1-tvrtko.ursulin@igalia.com/
> [2] https://lore.kernel.org/dri-devel/20260626081942.2122144-2-phasta@kernel.org/
> 
> Philipp Stanner (3):
>    drm/sched: Lock drm_sched_rq_pop_entity() externally
>    drm/sched: Lock spsc_queue_pop() in drm_sched_entity_pop_job()

FWIW if you could review 
https://lore.kernel.org/dri-devel/20260907130527.52530-1-tvrtko.ursulin@igalia.com/ 
you could drop the first two patches from your series. Extra benefit is 
that patch fixes a bug and has been tested by the user.

Regards,

Tvrtko

>    drm/sched: Protect entity->last_scheduled with spinlock
> 
>   drivers/gpu/drm/scheduler/sched_entity.c | 53 ++++++++++--------------
>   drivers/gpu/drm/scheduler/sched_rq.c     |  4 +-
>   include/drm/gpu_scheduler.h              | 10 ++---
>   3 files changed, 28 insertions(+), 39 deletions(-)
> 

Re: [PATCH v3 0/3] drm/sched: Introduce more locking to entity

[Philipp Stanner]

On Fri, 2026-09-11 at 09:19 +0100, Tvrtko Ursulin wrote:
> FWIW if you could review 
> https://lore.kernel.org/dri-devel/20260907130527.52530-1-tvrtko.ursulin@igalia.com/ 
> you could drop the first two patches from your series. Extra benefit is 
> that patch fixes a bug and has been tested by the user.

See the other thread; I'm not super-hard opposed, but if we can agree
on getting CFS to a non-experimental status by first improving
spsc_queue, then it would be nicer from the diff / git log perspective
to have these little patches as a preparational base-line for the spsc
rework :)

Greetings
Philipp