ck_ring: Memoize mask across all operations.

include/ck_ring.h

@@ -98,6 +98,7 @@
 				    struct type *data)				\
 	{									\
 		unsigned int consumer, producer;				\
+		unsigned int mask = ring->mask;					\
 										\
 		consumer = ring->c_head;					\
 		producer = ck_pr_load_uint(&ring->p_tail);			\
@@ -106,7 +107,7 @@
 			return (false);						\
 										\
 		ck_pr_fence_load();						\
-		*data = ring->ring[consumer & ring->mask];			\
+		*data = ring->ring[consumer & mask];				\
 		ck_pr_fence_store();						\
 		ck_pr_store_uint(&ring->c_head, consumer + 1);			\
 										\
@@ -123,6 +124,7 @@
 				       struct type *data)			\
 	{									\
 		unsigned int consumer, producer;				\
+		unsigned int mask = ring->mask;					\
 										\
 		consumer = ck_pr_load_uint(&ring->c_head);			\
 		ck_pr_fence_load();						\
@@ -132,7 +134,7 @@
 			return false;						\
 										\
 		ck_pr_fence_load();						\
-		*data = ring->ring[consumer & ring->mask];			\
+		*data = ring->ring[consumer & mask];				\
 		ck_pr_fence_memory();						\
 		return ck_pr_cas_uint(&ring->c_head,				\
 				      consumer,					\
@@ -284,6 +286,7 @@ CK_CC_INLINE static bool
 ck_ring_trydequeue_spmc(struct ck_ring *ring, void *data)
 {
 	unsigned int consumer, producer;
+	unsigned int mask = ring->mask;
 
 	consumer = ck_pr_load_uint(&ring->c_head);
 	ck_pr_fence_load();
@@ -293,7 +296,7 @@ ck_ring_trydequeue_spmc(struct ck_ring *ring, void *data)
 		return false;
 
 	ck_pr_fence_load();
-	ck_pr_store_ptr(data, ring->ring[consumer & ring->mask]);
+	ck_pr_store_ptr(data, ring->ring[consumer & mask]);
 	ck_pr_fence_memory();
 
 	return ck_pr_cas_uint(&ring->c_head, consumer, consumer + 1);
@@ -303,6 +306,7 @@ CK_CC_INLINE static bool
 ck_ring_dequeue_spmc(struct ck_ring *ring, void *data)
 {
 	unsigned int consumer, producer;
+	unsigned int mask = ring->mask;
 	void *r;
 
 	consumer = ck_pr_load_uint(&ring->c_head);
@@ -327,7 +331,7 @@ ck_ring_dequeue_spmc(struct ck_ring *ring, void *data)
 		 * volatile load to force volatile semantics while allowing
 		 * for r itself to remain aliased across the loop.
 		 */
-		r = ck_pr_load_ptr(&ring->ring[consumer & ring->mask]);
+		r = ck_pr_load_ptr(&ring->ring[consumer & mask]);
 
 		/* Serialize load with respect to head update. */
 		ck_pr_fence_memory();