@@ -120,6 +120,24 @@ reservation_object_get_excl(struct reservation_object *obj)
reservation_object_held(obj));
}
+static inline struct fence *
+reservation_object_get_excl_unlocked(struct reservation_object *obj)
+{
+ struct fence *fence;
+ unsigned seq;
+retry:
+ seq = read_seqcount_begin(&obj->seq);
+ rcu_read_lock();
+ fence = rcu_dereference(obj->fence_excl);
+ if (read_seqcount_retry(&obj->seq, seq)) {
+ rcu_read_unlock();
+ goto retry;
+ }
+ fence = fence_get(fence);
+ rcu_read_unlock();
+ return fence;
+}
+
int reservation_object_reserve_shared(struct reservation_object *obj);
void reservation_object_add_shared_fence(struct reservation_object *obj,
struct fence *fence);
In the atomic modesetting path, each driver simply wants to grab a ref to the exlusive fence from a reservation object to store in the incoming drm_plane_state, without doing the whole RCU dance. Since each driver will need to do this, lets make a helper. Signed-off-by: Rob Clark <robdclark@gmail.com> --- include/linux/reservation.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)