From cbc8764e29c2318229261a679b2aafd0f9072885 Mon Sep 17 00:00:00 2001 From: Tvrtko Ursulin Date: Tue, 24 Sep 2024 11:19:08 +0100 Subject: [PATCH] drm/sched: Always wake up correct scheduler in drm_sched_entity_push_job MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since drm_sched_entity_modify_sched() can modify the entities run queue, lets make sure to only dereference the pointer once so both adding and waking up are guaranteed to be consistent. Alternative of moving the spin_unlock to after the wake up would for now be more problematic since the same lock is taken inside drm_sched_rq_update_fifo(). v2: * Improve commit message. (Philipp) * Cache the scheduler pointer directly. (Christian) Signed-off-by: Tvrtko Ursulin Fixes: b37aced31eb0 ("drm/scheduler: implement a function to modify sched list") Cc: Christian König Cc: Alex Deucher Cc: Luben Tuikov Cc: Matthew Brost Cc: David Airlie Cc: Daniel Vetter Cc: Philipp Stanner Cc: dri-devel@lists.freedesktop.org Cc: # v5.7+ Reviewed-by: Christian König Link: https://patchwork.freedesktop.org/patch/msgid/20240924101914.2713-3-tursulin@igalia.com Signed-off-by: Christian König --- drivers/gpu/drm/scheduler/sched_entity.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 0e002c17fcb62..a75eede8bf8da 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -599,6 +599,9 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job) /* first job wakes up scheduler */ if (first) { + struct drm_gpu_scheduler *sched; + struct drm_sched_rq *rq; + /* Add the entity to the run queue */ spin_lock(&entity->rq_lock); if (entity->stopped) { @@ -608,13 +611,16 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job) return; } - drm_sched_rq_add_entity(entity->rq, entity); + rq = entity->rq; + sched = rq->sched; + + 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); + drm_sched_wakeup(sched); } } EXPORT_SYMBOL(drm_sched_entity_push_job);