Convert this piece of code to use C11 atomics.

As mentioned before, we should at least aim to have one piece of code in
both user space and kernel space that uses C11 atomics, to get some
coverage. This piece of code can be migrated trivially, so it's a good
candidate.

1 files changed, 4 insertions, 3 deletions

diff --git a/lib/librt/sigev_thread.c b/lib/librt/sigev_thread.c
index 0246c0c339cb..2677a8e50589 100644
--- a/lib/librt/sigev_thread.c
+++ b/lib/librt/sigev_thread.c
@@ -28,13 +28,13 @@
  */
 
 #include <sys/types.h>
-#include <machine/atomic.h>
 
 #include "namespace.h"
 #include <err.h>
 #include <errno.h>
 #include <ucontext.h>
 #include <sys/thr.h>
+#include <stdatomic.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -51,7 +51,7 @@ LIST_HEAD(sigev_list_head, sigev_node);
 static struct sigev_list_head	sigev_hash[HASH_QUEUES];
 static struct sigev_list_head	sigev_all;
 static LIST_HEAD(,sigev_thread)	sigev_threads;
-static unsigned int		sigev_generation;
+static atomic_int		sigev_generation;
 static pthread_mutex_t		*sigev_list_mtx;
 static pthread_once_t		sigev_once = PTHREAD_ONCE_INIT;
 static pthread_once_t		sigev_once_default = PTHREAD_ONCE_INIT;
@@ -196,7 +196,8 @@ __sigev_alloc(int type, const struct sigevent *evp, struct sigev_node *prev,
 	if (sn != NULL) {
 		sn->sn_value = evp->sigev_value;
 		sn->sn_func  = evp->sigev_notify_function;
-		sn->sn_gen   = atomic_fetchadd_int(&sigev_generation, 1);
+		sn->sn_gen   = atomic_fetch_add_explicit(&sigev_generation, 1,
+		    memory_order_relaxed);
 		sn->sn_type  = type;
 		_pthread_attr_init(&sn->sn_attr);
 		_pthread_attr_setdetachstate(&sn->sn_attr, PTHREAD_CREATE_DETACHED);