[PATCH 3/5] dma-buf: return only unsignaled fences in dma_fence_unwrap_for_each v3

["Christian König" <ckoenig.leichtzumerken@gmail.com>]

dma_fence_chain containers cleanup signaled fences automatically, so
filter those out from arrays as well.

v2: fix missing walk over the array
v3: massively simplify the patch and actually update the description.

Signed-off-by: Christian König <christian.koenig@amd.com>
---
 include/linux/dma-fence-unwrap.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/linux/dma-fence-unwrap.h b/include/linux/dma-fence-unwrap.h
index e7c219da4ed7..a4d342fef8e0 100644
--- a/include/linux/dma-fence-unwrap.h
+++ b/include/linux/dma-fence-unwrap.h
@@ -43,9 +43,13 @@ struct dma_fence *dma_fence_unwrap_next(struct dma_fence_unwrap *cursor);
  * Unwrap dma_fence_chain and dma_fence_array containers and deep dive into all
  * potential fences in them. If @head is just a normal fence only that one is
  * returned.
+ *
+ * Note that signalled fences are opportunistically filtered out, which
+ * means the iteration is potentially over no fence at all.
  */
 #define dma_fence_unwrap_for_each(fence, cursor, head)			\
 	for (fence = dma_fence_unwrap_first(head, cursor); fence;	\
-	     fence = dma_fence_unwrap_next(cursor))
+	     fence = dma_fence_unwrap_next(cursor))			\
+		if (!dma_fence_is_signaled(fence))
 
 #endif
-- 
2.25.1