From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Use rcu_dereference_protected() and rcu_assign_pointer() for accessing
the rcu protected syncobj->fence pointer. This eliminates several sparse
warnings.
Cc: Dave Airlie <airlied@xxxxxxxxxx>
Cc: Jason Ekstrand <jason@xxxxxxxxxxxxxx>
Cc: linaro-mm-sig@xxxxxxxxxxxxxxxx
Cc: linux-media@xxxxxxxxxxxxxxx
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: Christian König <christian.koenig@xxxxxxx>
Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_syncobj.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index f776fc1cc543..9b733c510cbf 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -106,7 +106,8 @@ static int drm_syncobj_fence_get_or_add_callback(struct drm_syncobj *syncobj,
* callback when a fence has already been set.
*/
if (syncobj->fence) {
- *fence = dma_fence_get(syncobj->fence);
+ *fence = dma_fence_get(rcu_dereference_protected(syncobj->fence,
+ lockdep_is_held(&syncobj->lock)));
ret = 1;
} else {
*fence = NULL;
@@ -168,8 +169,9 @@ void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
spin_lock(&syncobj->lock);
- old_fence = syncobj->fence;
- syncobj->fence = fence;
+ old_fence = rcu_dereference_protected(syncobj->fence,
+ lockdep_is_held(&syncobj->lock));
+ rcu_assign_pointer(syncobj->fence, fence);
if (fence != old_fence) {
list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node) {
@@ -659,7 +661,8 @@ static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
container_of(cb, struct syncobj_wait_entry, syncobj_cb);
/* This happens inside the syncobj lock */
- wait->fence = dma_fence_get(syncobj->fence);
+ wait->fence = dma_fence_get(rcu_dereference_protected(syncobj->fence,
+ lockdep_is_held(&syncobj->lock)));
wake_up_process(wait->task);
}
--
2.13.6
