[PATCH 1/7] dma-buf/dma-fence: Extract __dma_fence_is_later()

[Chris Wilson]

Often we have the task of comparing two seqno known to be on the same
context, so provide a common __dma_fence_is_later().

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Sumit Semwal <sumit.semwal at linaro.org>
Cc: Sean Paul <seanpaul at chromium.org>
Cc: Gustavo Padovan <gustavo at padovan.org>
---
 include/linux/dma-fence.h | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h
index a5195a7d6f77..ac5987989e9a 100644
--- a/include/linux/dma-fence.h
+++ b/include/linux/dma-fence.h
@@ -336,6 +336,19 @@ dma_fence_is_signaled(struct dma_fence *fence)
 }
 
 /**
+ * __dma_fence_is_later - return if f1 is chronologically later than f2
+ * @f1:	[in]	the first fence's seqno
+ * @f2:	[in]	the second fence's seqno from the same context
+ *
+ * Returns true if f1 is chronologically later than f2. Both fences must be
+ * from the same context, since a seqno is not common across contexts.
+ */
+static inline bool __dma_fence_is_later(u32 f1, u32 f2)
+{
+	return (int)(f1 - f2) > 0;
+}
+
+/**
  * dma_fence_is_later - return if f1 is chronologically later than f2
  * @f1:	[in]	the first fence from the same context
  * @f2:	[in]	the second fence from the same context
@@ -349,7 +362,7 @@ static inline bool dma_fence_is_later(struct dma_fence *f1,
 	if (WARN_ON(f1->context != f2->context))
 		return false;
 
-	return (int)(f1->seqno - f2->seqno) > 0;
+	return __dma_fence_is_later(f1->seqno, f2->seqno);
 }
 
 /**
-- 
2.13.1