X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=include%2Furcu%2Fstatic%2Frculfqueue.h;h=03c4ecdef76c6ee55102e5b36caaea5dee954841;hb=HEAD;hp=ad73454ed57e5e9f3a4a4c10fb26a69af3bc978f;hpb=2875743718fb23293190b5edd0f2b530977270b1;p=urcu.git

diff --git a/include/urcu/static/rculfqueue.h b/include/urcu/static/rculfqueue.h
index ad73454..03c4ecd 100644
--- a/include/urcu/static/rculfqueue.h
+++ b/include/urcu/static/rculfqueue.h
@@ -1,29 +1,15 @@
+// SPDX-FileCopyrightText: 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
 #ifndef _URCU_RCULFQUEUE_STATIC_H
 #define _URCU_RCULFQUEUE_STATIC_H
 
 /*
- * rculfqueue-static.h
- *
  * Userspace RCU library - Lock-Free RCU Queue
  *
- * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
  * TO BE INCLUDED ONLY IN LGPL-COMPATIBLE CODE. See rculfqueue.h for linking
  * dynamically with the userspace rcu library.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include <urcu-call-rcu.h>
@@ -148,26 +134,29 @@ void _cds_lfq_enqueue_rcu(struct cds_lfq_queue_rcu *q,
 	 * uatomic_cmpxchg() implicit memory barrier orders earlier stores to
 	 * node before publication.
 	 */
-
 	for (;;) {
 		struct cds_lfq_node_rcu *tail, *next;
 
 		tail = rcu_dereference(q->tail);
-		next = uatomic_cmpxchg(&tail->next, NULL, node);
+		cmm_emit_legacy_smp_mb();
+		next = uatomic_cmpxchg_mo(&tail->next, NULL, node,
+					CMM_SEQ_CST, CMM_SEQ_CST);
 		if (next == NULL) {
 			/*
 			 * Tail was at the end of queue, we successfully
 			 * appended to it. Now move tail (another
 			 * enqueue might beat us to it, that's fine).
 			 */
-			(void) uatomic_cmpxchg(&q->tail, tail, node);
+			(void) uatomic_cmpxchg_mo(&q->tail, tail, node,
+						CMM_SEQ_CST, CMM_SEQ_CST);
 			return;
 		} else {
 			/*
 			 * Failure to append to current tail.
 			 * Help moving tail further and retry.
 			 */
-			(void) uatomic_cmpxchg(&q->tail, tail, next);
+			(void) uatomic_cmpxchg_mo(&q->tail, tail, next,
+						CMM_SEQ_CST, CMM_SEQ_CST);
 			continue;
 		}
 	}
@@ -211,7 +200,8 @@ struct cds_lfq_node_rcu *_cds_lfq_dequeue_rcu(struct cds_lfq_queue_rcu *q)
 			enqueue_dummy(q);
 			next = rcu_dereference(head->next);
 		}
-		if (uatomic_cmpxchg(&q->head, head, next) != head)
+		if (uatomic_cmpxchg_mo(&q->head, head, next,
+					CMM_SEQ_CST, CMM_SEQ_CST) != head)
 			continue;	/* Concurrently pushed. */
 		if (head->dummy) {
 			/* Free dummy after grace period. */