[v3,03/39] stack: use C11 alignas

Message ID 1707894382-307-4-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State Superseded, archived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).

Signed-off-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
---
 lib/stack/rte_stack.h | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)
  

Patch

diff --git a/lib/stack/rte_stack.h b/lib/stack/rte_stack.h
index a379300..8ff0659 100644
--- a/lib/stack/rte_stack.h
+++ b/lib/stack/rte_stack.h
@@ -15,6 +15,8 @@ 
 #ifndef _RTE_STACK_H_
 #define _RTE_STACK_H_
 
+#include <stdalign.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -42,7 +44,7 @@  struct rte_stack_lf_head {
 
 struct rte_stack_lf_list {
 	/** List head */
-	struct rte_stack_lf_head head __rte_aligned(16);
+	alignas(16) struct rte_stack_lf_head head;
 	/** List len */
 	RTE_ATOMIC(uint64_t) len;
 };
@@ -52,11 +54,11 @@  struct rte_stack_lf_list {
  */
 struct rte_stack_lf {
 	/** LIFO list of elements */
-	struct rte_stack_lf_list used __rte_cache_aligned;
+	alignas(RTE_CACHE_LINE_SIZE) struct rte_stack_lf_list used;
 	/** LIFO list of free elements */
-	struct rte_stack_lf_list free __rte_cache_aligned;
+	alignas(RTE_CACHE_LINE_SIZE) struct rte_stack_lf_list free;
 	/** LIFO elements */
-	struct rte_stack_lf_elem elems[] __rte_cache_aligned;
+	alignas(RTE_CACHE_LINE_SIZE) struct rte_stack_lf_elem elems[];
 };
 
 /* Structure containing the LIFO, its current length, and a lock for mutual
@@ -71,9 +73,9 @@  struct rte_stack_std {
 /* The RTE stack structure contains the LIFO structure itself, plus metadata
  * such as its name and memzone pointer.
  */
-struct rte_stack {
+struct __rte_cache_aligned rte_stack {
 	/** Name of the stack. */
-	char name[RTE_STACK_NAMESIZE] __rte_cache_aligned;
+	alignas(RTE_CACHE_LINE_SIZE) char name[RTE_STACK_NAMESIZE];
 	/** Memzone containing the rte_stack structure. */
 	const struct rte_memzone *memzone;
 	uint32_t capacity; /**< Usable size of the stack. */
@@ -82,7 +84,7 @@  struct rte_stack {
 		struct rte_stack_lf stack_lf; /**< Lock-free LIFO structure. */
 		struct rte_stack_std stack_std;	/**< LIFO structure. */
 	};
-} __rte_cache_aligned;
+};
 
 /**
  * The stack uses lock-free push and pop functions. This flag is only