drm/scheduler: Remove obsolete spinlock.

This spinlock is superfluous, any call to drm_sched_entity_push_job
should already be under a lock together with matching drm_sched_job_init
to match the order of insertion into queue with job's fence seqence
number.

v2:
Improve patch description.
Add functions documentation describing the locking considerations

Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Acked-by: Chunming Zhou <david1.zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Andrey Grodzovsky 2018-05-15 14:42:20 -04:00 committed by Alex Deucher
parent b9245b9498
commit 563e1e664d
2 changed files with 10 additions and 6 deletions

View file

@ -139,7 +139,6 @@ int drm_sched_entity_init(struct drm_gpu_scheduler *sched,
entity->last_scheduled = NULL;
spin_lock_init(&entity->rq_lock);
spin_lock_init(&entity->queue_lock);
spsc_queue_init(&entity->job_queue);
atomic_set(&entity->fence_seq, 0);
@ -413,6 +412,10 @@ drm_sched_entity_pop_job(struct drm_sched_entity *entity)
*
* @sched_job The pointer to job required to submit
*
* Note: To guarantee that the order of insertion to queue matches
* the job's fence sequence number this function should be
* called with drm_sched_job_init under common lock.
*
* Returns 0 for success, negative error code otherwise.
*/
void drm_sched_entity_push_job(struct drm_sched_job *sched_job,
@ -423,11 +426,8 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job,
trace_drm_sched_job(sched_job, entity);
spin_lock(&entity->queue_lock);
first = spsc_queue_push(&entity->job_queue, &sched_job->queue_node);
spin_unlock(&entity->queue_lock);
/* first job wakes up scheduler */
if (first) {
/* Add the entity to the run queue */
@ -593,7 +593,12 @@ void drm_sched_job_recovery(struct drm_gpu_scheduler *sched)
}
EXPORT_SYMBOL(drm_sched_job_recovery);
/* init a sched_job with basic field */
/**
* Init a sched_job with basic field
*
* Note: Refer to drm_sched_entity_push_job documentation
* for locking considerations.
*/
int drm_sched_job_init(struct drm_sched_job *job,
struct drm_gpu_scheduler *sched,
struct drm_sched_entity *entity,

View file

@ -56,7 +56,6 @@ struct drm_sched_entity {
spinlock_t rq_lock;
struct drm_gpu_scheduler *sched;
spinlock_t queue_lock;
struct spsc_queue job_queue;
atomic_t fence_seq;