From: Ville Syrjälä ville.syrjala@linux.intel.com
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@redhat.com Cc: Jason Ekstrand jason@jlekstrand.net Cc: linaro-mm-sig@lists.linaro.org Cc: linux-media@vger.kernel.org Cc: Alex Deucher alexander.deucher@amd.com Cc: Christian König christian.koenig@amd.com Cc: Sumit Semwal sumit.semwal@linaro.org Cc: Chris Wilson chris@chris-wilson.co.uk Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com --- 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); }