Linux-libre 4.6.2-gnu

2 files changed, 31 insertions, 2 deletions

diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
index 8b2becd1a..a5ff9458d 100644
--- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
+++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
@@ -229,6 +229,14 @@ static void amd_sched_entity_wakeup(struct fence *f, struct fence_cb *cb)
 	amd_sched_wakeup(entity->sched);
 }
 
+static void amd_sched_entity_clear_dep(struct fence *f, struct fence_cb *cb)
+{
+	struct amd_sched_entity *entity =
+		container_of(cb, struct amd_sched_entity, cb);
+	entity->dependency = NULL;
+	fence_put(f);
+}
+
 static bool amd_sched_entity_add_dependency_cb(struct amd_sched_entity *entity)
 {
 	struct amd_gpu_scheduler *sched = entity->sched;
@@ -251,7 +259,7 @@ static bool amd_sched_entity_add_dependency_cb(struct amd_sched_entity *entity)
 		}
 
 		/* Wait for fence to be scheduled */
-		entity->cb.func = amd_sched_entity_wakeup;
+		entity->cb.func = amd_sched_entity_clear_dep;
 		list_add_tail(&entity->cb.node, &s_fence->scheduled_cb);
 		return true;
 	}
diff --git a/drivers/gpu/drm/amd/scheduler/sched_fence.c b/drivers/gpu/drm/amd/scheduler/sched_fence.c
index 87c78eece..dc115aea3 100644
--- a/drivers/gpu/drm/amd/scheduler/sched_fence.c
+++ b/drivers/gpu/drm/amd/scheduler/sched_fence.c
@@ -84,12 +84,33 @@ static bool amd_sched_fence_enable_signaling(struct fence *f)
 	return true;
 }
 
-static void amd_sched_fence_release(struct fence *f)
+/**
+ * amd_sched_fence_free - free up the fence memory
+ *
+ * @rcu: RCU callback head
+ *
+ * Free up the fence memory after the RCU grace period.
+ */
+static void amd_sched_fence_free(struct rcu_head *rcu)
 {
+	struct fence *f = container_of(rcu, struct fence, rcu);
 	struct amd_sched_fence *fence = to_amd_sched_fence(f);
 	kmem_cache_free(sched_fence_slab, fence);
 }
 
+/**
+ * amd_sched_fence_release - callback that fence can be freed
+ *
+ * @fence: fence
+ *
+ * This function is called when the reference count becomes zero.
+ * It just RCU schedules freeing up the fence.
+ */
+static void amd_sched_fence_release(struct fence *f)
+{
+	call_rcu(&f->rcu, amd_sched_fence_free);
+}
+
 const struct fence_ops amd_sched_fence_ops = {
 	.get_driver_name = amd_sched_fence_get_driver_name,
 	.get_timeline_name = amd_sched_fence_get_timeline_name,