On 24/09/2024 14:55, Christian König wrote:
I've pushed the first to drm-misc-next, but that one here fails to apply
cleanly.
This appears due 440d52b370b0 ("drm/sched: Fix dynamic job-flow control
race") in drm-misc-fixes.
In theory 1-3 from my series are fixes. Should they also go to
drm-misc-fixes? I am not too familiar with the drm-misc flow.
Or the series now needs to wait for some backmerge?
Regards,
Tvrtko
Am 24.09.24 um 12:19 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 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 <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: Philipp Stanner <pstanner@xxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: <stable@xxxxxxxxxxxxxxx> # v5.7+
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
---
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 0e002c17fcb6..a75eede8bf8d 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);
