Commit e1b4ce25 authored by Christian König's avatar Christian König Committed by Alex Deucher
Browse files

drm/scheduler: use job count instead of peek 



The spsc_queue_peek function is accessing queue->head which belongs to
the consumer thread and shouldn't be accessed by the producer

This is fixing a rare race condition when destroying entities.

Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
Acked-by: default avatarAndrey Grodzovsky <andrey.grodzovsky@amd.com>
Reviewed-by: default avatar <Monk.liu@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 31ec0dd3

drivers/gpu/drm/scheduler/sched_entity.c

+2 −2
Original line number Original line Diff line number Diff line
@@ -95,7 +95,7 @@ static bool drm_sched_entity_is_idle(struct drm_sched_entity *entity) 
	rmb(); /* for list_empty to work without lock */

	rmb(); /* for list_empty to work without lock */





	if (list_empty(&entity->list) ||

	if (list_empty(&entity->list) ||

	    spsc_queue_peek(&entity->job_queue) == NULL)

	    spsc_queue_count(&entity->job_queue) == 0)

		return true;

		return true;





	return false;

	return false;
@@ -281,7 +281,7 @@ void drm_sched_entity_fini(struct drm_sched_entity *entity) 
	/* Consumption of existing IBs wasn't completed. Forcefully

	/* Consumption of existing IBs wasn't completed. Forcefully

	 * remove them here.

	 * remove them here.

	 */

	 */

	if (spsc_queue_peek(&entity->job_queue)) {

	if (spsc_queue_count(&entity->job_queue)) {

		if (sched) {

		if (sched) {

			/* Park the kernel for a moment to make sure it isn't processing

			/* Park the kernel for a moment to make sure it isn't processing

			 * our enity.

			 * our enity.

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