drm/sched: Add drm_sched_start_timeout_unlocked helper

Also add a lockdep assert to drm_sched_start_timeout.
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Link: https://lore.kernel.org/r/20231031032439.1558703-5-matthew.brost@intel.comSigned-off-by: Luben Tuikov <ltuikov89@gmail.com>

drivers/gpu/drm/scheduler/sched_main.c

@@ -334,11 +334,20 @@ static void drm_sched_job_done_cb(struct dma_fence *f, struct dma_fence_cb *cb)
  */
 static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
 {
+	lockdep_assert_held(&sched->job_list_lock);
+
 	if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
 	    !list_empty(&sched->pending_list))
 		queue_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
 }
 
+static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
+{
+	spin_lock(&sched->job_list_lock);
+	drm_sched_start_timeout(sched);
+	spin_unlock(&sched->job_list_lock);
+}
+
 /**
  * drm_sched_fault - immediately start timeout handler
  *
@@ -451,11 +460,8 @@ static void drm_sched_job_timedout(struct work_struct *work)
 		spin_unlock(&sched->job_list_lock);
 	}
 
-	if (status != DRM_GPU_SCHED_STAT_ENODEV) {
-		spin_lock(&sched->job_list_lock);
-		drm_sched_start_timeout(sched);
-		spin_unlock(&sched->job_list_lock);
-	}
+	if (status != DRM_GPU_SCHED_STAT_ENODEV)
+		drm_sched_start_timeout_unlocked(sched);
 }
 
 /**
@@ -581,11 +587,8 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
 			drm_sched_job_done(s_job, -ECANCELED);
 	}
 
-	if (full_recovery) {
-		spin_lock(&sched->job_list_lock);
-		drm_sched_start_timeout(sched);
-		spin_unlock(&sched->job_list_lock);
-	}
+	if (full_recovery)
+		drm_sched_start_timeout_unlocked(sched);
 
 	drm_sched_wqueue_start(sched);
 }