Re: [RFC 2/4] drm/sched: Always wake up correct scheduler in drm_sched_entity_push_job

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Am 06.09.24 um 20:06 schrieb Tvrtko Ursulin:
From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxx>

Since drm_sched_entity_modify_sched() can modify the entities run queue
lets make sure to only derefernce the pointer once so both adding and
waking up are guaranteed to be consistent.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxx>
Fixes: b37aced31eb0 ("drm/scheduler: implement a function to modify sched list")
Cc: Christian König <christian.koenig@xxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: Luben Tuikov <ltuikov89@xxxxxxxxx>
Cc: Matthew Brost <matthew.brost@xxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: <stable@xxxxxxxxxxxxxxx> # v5.7+
---
  drivers/gpu/drm/scheduler/sched_entity.c | 8 ++++++--
  1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index ae8be30472cd..62b07ef7630a 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -599,6 +599,8 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
/* first job wakes up scheduler */
  	if (first) {
+		struct drm_sched_rq *rq;
+

I think we should go a step further and keep the scheduler to wake up and not the rq.

Regards,
Christian.

  		/* Add the entity to the run queue */
  		spin_lock(&entity->rq_lock);
  		if (entity->stopped) {
@@ -608,13 +610,15 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
  			return;
  		}
- drm_sched_rq_add_entity(entity->rq, entity);
+		rq = entity->rq;
+
+		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_wakeup(entity->rq->sched, entity);
+		drm_sched_wakeup(rq->sched, entity);
  	}
  }
  EXPORT_SYMBOL(drm_sched_entity_push_job);





[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux