drm/sched: select new rq even if there is only one v3

This is necessary when changing priorities of an entity.

v2: test the sched_list instead of num_sched.
v3: set the sched_list to NULL when there is only one entry
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NSonny Jiang <sonny.jiang@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210305125155.2312-1-christian.koenig@amd.com

drivers/gpu/drm/scheduler/sched_entity.c

@@ -453,7 +453,7 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
 	struct drm_gpu_scheduler *sched;
 	struct drm_sched_rq *rq;
 
-	if (spsc_queue_count(&entity->job_queue) || entity->num_sched_list <= 1)
+	if (spsc_queue_count(&entity->job_queue) || !entity->sched_list)
 		return;
 
 	fence = READ_ONCE(entity->last_scheduled);
@@ -467,8 +467,10 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
 		drm_sched_rq_remove_entity(entity->rq, entity);
 		entity->rq = rq;
 	}
-
 	spin_unlock(&entity->rq_lock);
+
+	if (entity->num_sched_list == 1)
+		entity->sched_list = NULL;
 }
 
 /**