[RFC v4 12/16] drm/sched: Remove idle entity from tree

[Tvrtko Ursulin]

There is no need to keep entities with no jobs in the tree so lets remove
it once the last job is consumed. This keeps the tree smaller which is
nicer and more efficient as entities are removed and re-added on every
popped job.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursu...@igalia.com>
Cc: Christian König <christian.koe...@amd.com>
Cc: Danilo Krummrich <d...@kernel.org>
Cc: Matthew Brost <matthew.br...@intel.com>
Cc: Philipp Stanner <pha...@kernel.org>
---
 drivers/gpu/drm/scheduler/sched_rq.c | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_rq.c 
b/drivers/gpu/drm/scheduler/sched_rq.c
index d477a027feb9..2cde89cf25fb 100644
--- a/drivers/gpu/drm/scheduler/sched_rq.c
+++ b/drivers/gpu/drm/scheduler/sched_rq.c
@@ -149,25 +149,27 @@ void drm_sched_rq_pop_entity(struct drm_sched_entity 
*entity)
 {
        struct drm_sched_job *next_job;
        struct drm_sched_rq *rq;
-       ktime_t ts;
 
        /*
         * Update the entity's location in the min heap according to
         * the timestamp of the next job, if any.
         */
+       spin_lock(&entity->lock);
+       rq = entity->rq;
+       spin_lock(&rq->lock);
        next_job = drm_sched_entity_queue_peek(entity);
-       if (!next_job)
-               return;
+       if (next_job) {
+               ktime_t ts;
 
-       if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
-               ts = next_job->submit_ts;
-       else
-               ts = drm_sched_rq_get_rr_deadline(rq);
+               if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
+                       ts = next_job->submit_ts;
+               else
+                       ts = drm_sched_rq_get_rr_deadline(rq);
 
-       spin_lock(&entity->lock);
-       rq = entity->rq;
-       spin_lock(&rq->lock);
-       drm_sched_rq_update_fifo_locked(entity, rq, ts);
+               drm_sched_rq_update_fifo_locked(entity, rq, ts);
+       } else {
+               drm_sched_rq_remove_fifo_locked(entity, rq);
+       }
        spin_unlock(&rq->lock);
        spin_unlock(&entity->lock);
 }
-- 
2.48.0