diff mbox series

[v3,05/39] ring: use C11 alignas

Message ID 1707894382-307-6-git-send-email-roretzla@linux.microsoft.com (mailing list archive)
State Superseded, archived
Delegated to: David Marchand
Headers
Series use C11 alignas and normalize type alignment |

Checks

Context Check Description
ci/checkpatch success coding style OK

Commit Message

Tyler Retzlaff Feb. 14, 2024, 7:05 a.m. UTC 
  * Move __rte_aligned from the end of {struct,union} definitions to
  be between {struct,union} and tag.

  The placement between {struct,union} and the tag allows the desired
  alignment to be imparted on the type regardless of the toolchain being
  used for all of GCC, LLVM, MSVC compilers building both C and C++.

* Replace use of __rte_aligned(a) on variables/fields with alignas(a).

* Remove explicit alignment with __rte_aligned(8) from
  RTE_ATOMIC(uint64_t) raw fields in the absence of packing the fields
  should be naturally aligned to 8.

Signed-off-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
---
 lib/ring/rte_ring_core.h    | 16 +++++++++-------
 lib/ring/rte_ring_peek_zc.h |  4 ++--
 2 files changed, 11 insertions(+), 9 deletions(-)
diff mbox series

Patch

diff --git a/lib/ring/rte_ring_core.h b/lib/ring/rte_ring_core.h
index b770873..6cb2a91 100644
--- a/lib/ring/rte_ring_core.h
+++ b/lib/ring/rte_ring_core.h
@@ -19,6 +19,8 @@ 
  * instead.
  */
 
+#include <stdalign.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -78,7 +80,7 @@  struct rte_ring_headtail {
 
 union __rte_ring_rts_poscnt {
 	/** raw 8B value to read/write *cnt* and *pos* as one atomic op */
-	RTE_ATOMIC(uint64_t) raw __rte_aligned(8);
+	RTE_ATOMIC(uint64_t) raw;
 	struct {
 		uint32_t cnt; /**< head/tail reference counter */
 		uint32_t pos; /**< head/tail position */
@@ -94,7 +96,7 @@  struct rte_ring_rts_headtail {
 
 union __rte_ring_hts_pos {
 	/** raw 8B value to read/write *head* and *tail* as one atomic op */
-	RTE_ATOMIC(uint64_t) raw __rte_aligned(8);
+	RTE_ATOMIC(uint64_t) raw;
 	struct {
 		RTE_ATOMIC(uint32_t) head; /**< head position */
 		RTE_ATOMIC(uint32_t) tail; /**< tail position */
@@ -117,7 +119,7 @@  struct rte_ring_hts_headtail {
  * a problem.
  */
 struct rte_ring {
-	char name[RTE_RING_NAMESIZE] __rte_cache_aligned;
+	alignas(RTE_CACHE_LINE_SIZE) char name[RTE_RING_NAMESIZE];
 	/**< Name of the ring. */
 	int flags;               /**< Flags supplied at creation. */
 	const struct rte_memzone *memzone;
@@ -129,20 +131,20 @@  struct rte_ring {
 	RTE_CACHE_GUARD;
 
 	/** Ring producer status. */
-	union {
+	union __rte_cache_aligned {
 		struct rte_ring_headtail prod;
 		struct rte_ring_hts_headtail hts_prod;
 		struct rte_ring_rts_headtail rts_prod;
-	}  __rte_cache_aligned;
+	};
 
 	RTE_CACHE_GUARD;
 
 	/** Ring consumer status. */
-	union {
+	union __rte_cache_aligned {
 		struct rte_ring_headtail cons;
 		struct rte_ring_hts_headtail hts_cons;
 		struct rte_ring_rts_headtail rts_cons;
-	}  __rte_cache_aligned;
+	};
 
 	RTE_CACHE_GUARD;
 };
diff --git a/lib/ring/rte_ring_peek_zc.h b/lib/ring/rte_ring_peek_zc.h
index 8fb279c..0b5e34b 100644
--- a/lib/ring/rte_ring_peek_zc.h
+++ b/lib/ring/rte_ring_peek_zc.h
@@ -79,7 +79,7 @@ 
  * This structure contains the pointers and length of the space
  * reserved on the ring storage.
  */
-struct rte_ring_zc_data {
+struct __rte_cache_aligned rte_ring_zc_data {
 	/* Pointer to the first space in the ring */
 	void *ptr1;
 	/* Pointer to the second space in the ring if there is wrap-around.
@@ -92,7 +92,7 @@  struct rte_ring_zc_data {
 	 * will give the number of elements available at ptr2.
 	 */
 	unsigned int n1;
-} __rte_cache_aligned;
+};
 
 static __rte_always_inline void
 __rte_ring_get_elem_addr(struct rte_ring *r, uint32_t head,