X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=urcu.h;h=5d92aa7232d4d0b53d262115fefc470d14286af0;hp=0b0d232311a58666c8b41a9c3162b4efb8caaed4;hb=4d1ce26fea0296ff67791c881836393fdd020cf9;hpb=121a5d44c8cc7197116df73854cb94c6cfbad0b0

diff --git a/urcu.h b/urcu.h
index 0b0d232..5d92aa7 100644
--- a/urcu.h
+++ b/urcu.h
@@ -6,17 +6,27 @@
  *
  * Userspace RCU header
  *
- * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
- *
- * Credits for Paul E. McKenney <paulmck@linux.vnet.ibm.com>
- * for inspiration coming from the Linux kernel RCU and rcu-preempt.
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
  *
  * LGPL-compatible code should include this header with :
  *
  * #define _LGPL_SOURCE
  * #include <urcu.h>
  *
- * Distributed under LGPLv2.1
+ * 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
  *
  * IBM's contributions to this file may be relicensed under LGPLv2 or later.
  */
@@ -24,6 +34,14 @@
 #include <stdlib.h>
 #include <pthread.h>
 
+/*
+ * Important !
+ *
+ * Each thread containing read-side critical sections must be registered
+ * with rcu_register_thread() before calling rcu_read_lock().
+ * rcu_unregister_thread() should be called before the thread exits.
+ */
+
 #ifdef _LGPL_SOURCE
 
 #include <urcu-static.h>
@@ -57,6 +75,10 @@ extern void *rcu_assign_pointer_sym(void **p, void *v);
 #define rcu_assign_pointer(p, v)			\
 	rcu_assign_pointer_sym((void **)(p), (v))
 
+extern void *rcu_cmpxchg_pointer_sym(void **p, void *old, void *_new);
+#define rcu_cmpxchg_pointer(p, old, _new)		\
+	rcu_cmpxchg_pointer_sym((void **)(p), (old), (_new))
+
 extern void *rcu_xchg_pointer_sym(void **p, void *v);
 #define rcu_xchg_pointer(p, v)				\
 	rcu_xchg_pointer_sym((void **)(p), (v))