drm/sched: Re-group and rename the entity run-queue lock

When writing to a drm_sched_entity's run-queue, writers are protected
through the lock drm_sched_entity.rq_lock. This naming, however,
frequently collides with the separate internal lock of struct
drm_sched_rq, resulting in uses like this:

	spin_lock(&entity->rq_lock);
	spin_lock(&entity->rq->lock);

Rename drm_sched_entity.rq_lock to improve readability. While at it,
re-order that struct's members to make it more obvious what the lock
protects.

v2:
 * Rename some rq_lock straddlers in kerneldoc, improve commit text. (Philipp)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Suggested-by: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Luben Tuikov <ltuikov89@gmail.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Philipp Stanner <pstanner@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
[pstanner: Fix typo in docstring]
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241016122013.7857-5-tursulin@igalia.com

1 files changed, 11 insertions, 10 deletions

diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index b6d095074c19..e2b612817e3b 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -97,13 +97,21 @@ struct drm_sched_entity {
 	struct list_head		list;
 
 	/**
+	 * @lock:
+	 *
+	 * Lock protecting the run-queue (@rq) to which this entity belongs,
+	 * @priority and the list of schedulers (@sched_list, @num_sched_list).
+	 */
+	spinlock_t			lock;
+
+	/**
 	 * @rq:
 	 *
 	 * Runqueue on which this entity is currently scheduled.
 	 *
 	 * FIXME: Locking is very unclear for this. Writers are protected by
-	 * @rq_lock, but readers are generally lockless and seem to just race
-	 * with not even a READ_ONCE.
+	 * @lock, but readers are generally lockless and seem to just race with
+	 * not even a READ_ONCE.
 	 */
 	struct drm_sched_rq		*rq;
 
@@ -136,18 +144,11 @@ struct drm_sched_entity {
 	 * @priority:
 	 *
 	 * Priority of the entity. This can be modified by calling
-	 * drm_sched_entity_set_priority(). Protected by &rq_lock.
+	 * drm_sched_entity_set_priority(). Protected by @lock.
 	 */
 	enum drm_sched_priority         priority;
 
 	/**
-	 * @rq_lock:
-	 *
-	 * Lock to modify the runqueue to which this entity belongs.
-	 */
-	spinlock_t			rq_lock;
-
-	/**
 	 * @job_queue: the list of jobs of this entity.
 	 */
 	struct spsc_queue		job_queue;