RCU list: add rcuhlist.h, add list_replace_rcu

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/Makefile.am b/Makefile.am
index 4f915e13bb31eece195a6a53ae3a48d7ace8f396..33c7b538b773c536c030931a70ad571d4aba8cfd 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -6,7 +6,7 @@ SUBDIRS = . tests
 
 include_HEADERS = urcu.h $(top_srcdir)/urcu-*.h
 nobase_dist_include_HEADERS = urcu/compiler.h urcu/hlist.h urcu/list.h \
-               urcu/rculist.h urcu/system.h urcu/urcu-futex.h
+               urcu/rculist.h urcu/rcuhlist.h urcu/system.h urcu/urcu-futex.h
 nobase_nodist_include_HEADERS = urcu/arch.h urcu/uatomic_arch.h urcu/config.h
 
 EXTRA_DIST = $(top_srcdir)/urcu/arch_*.h $(top_srcdir)/urcu/uatomic_arch_*.h \

diff --git a/urcu/hlist.h b/urcu/hlist.h
index 1bec11a51272ea007c66c3ac3956104fc20e0bbf..9f7776fa7391f5093d431957b140aad98253b45c 100644 (file)
--- a/urcu/hlist.h
+++ b/urcu/hlist.h
@@ -9,6 +9,8 @@
  *
  * Author: Jan Blunck <jblunck@suse.de>
  *
+ * Copyright (C) 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU Lesser General Public License version 2.1 as
  * published by the Free  Software Foundation.

diff --git a/urcu/list.h b/urcu/list.h
index 6384728bc054d551fccd811cec27f43dc41d61da..d26751204192993c68c48010f7e931e18c6bfa2b 100644 (file)
--- a/urcu/list.h
+++ b/urcu/list.h
@@ -88,6 +88,17 @@ list_move (list_t *elem, list_t *head)
   list_add (elem, head);
 }
 
+/* replace an old entry.
+ */
+static inline void
+list_replace(list_t *old, list_t *_new)
+{
+       _new->next = old->next;
+       _new->prev = old->prev;
+       _new->prev->next = _new;
+       _new->next->prev = _new;
+}
+
 /* Join two lists.  */
 static inline void
 list_splice (list_t *add, list_t *head)

diff --git a/urcu/rcuhlist.h b/urcu/rcuhlist.h
new file mode 100644 (file)
index 0000000..be74145
--- /dev/null
+++ b/urcu/rcuhlist.h
@@ -0,0 +1,64 @@
+/* Copyright (C) 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   Copyright (C) 2009 Pierre-Marc Fournier
+   Conversion to RCU list.
+   Copyright (C) 2010 Mathieu Desnoyers
+
+   The GNU C 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.
+
+   The GNU C 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 the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _URCU_RCUHLIST_H
+#define _URCU_RCUHLIST_H
+
+#include <urcu/hlist.h>
+#include <urcu/arch.h>
+#include <urcu-pointer.h>
+
+/* Add new element at the head of the list.
+ */
+static inline void hlist_add_head(struct hlist_node *newp,
+                                 struct hlist_head *head)
+{
+       newp->next = head->next;
+       newp->prev = (struct hlist_node *)head;
+       smp_wmb();
+       if (head->next)
+               head->next->prev = newp;
+       head->next = newp;
+}
+
+/* Remove element from list. */
+static inline void hlist_del_rcu(struct hlist_node *elem)
+{
+       if (elem->next)
+               elem->next->prev = elem->prev;
+       elem->prev->next = elem->next;
+}
+
+
+/* Iterate through elements of the list.
+ * This must be done while rcu_read_lock() is held.
+ */
+
+#define hlist_for_each_entry_rcu(entry, pos, head, member)             \
+       for (pos = rcu_dereference((head)->next),                       \
+                    entry = hlist_entry(pos, typeof(*entry), member);  \
+            pos != NULL;                                               \
+            pos = rcu_dereference(pos->next),                          \
+                    entry = hlist_entry(pos, typeof(*entry), member))
+
+#endif /* _URCU_RCUHLIST_H */

diff --git a/urcu/rculist.h b/urcu/rculist.h
index e0ff93923fa3ffd2b5675fc273f4ebd6ddf3b3e6..b0c4f1a9d1e4430b538d737bc69246b2e789ce65 100644 (file)
--- a/urcu/rculist.h
+++ b/urcu/rculist.h
@@ -4,6 +4,7 @@
 
    Copyright (C) 2009 Pierre-Marc Fournier
    Conversion to RCU list.
+   Copyright (C) 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 
    The GNU C Library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
@@ -38,6 +39,15 @@ static inline void list_add_rcu(list_t *newp, list_t *head)
        head->next = newp;
 }
 
+/* replace an old entry atomically.
+ */
+static inline void list_replace_rcu(list_t *old, list_t *_new)
+{
+       _new->next = old->next;
+       _new->prev = old->prev;
+       rcu_assign_pointer(_new->prev->next, _new);
+       _new->next->prev = _new;
+}
 
 /* Remove element from list. */
 static inline void list_del_rcu(list_t *elem)
@@ -46,11 +56,19 @@ static inline void list_del_rcu(list_t *elem)
        elem->prev->next = elem->next;
 }
 
+/*
+ * Iteration through all elements of the list must be done while rcu_read_lock()
+ * is held.
+ */
+
+/* Iterate forward over the elements of the list.  */
+#define list_for_each_rcu(pos, head) \
+  for (pos = rcu_dereference((head)->next); pos != (head); \
+       pos = rcu_dereference(pos->next))
+
 
 /* Iterate through elements of the list.
- * This must be done while rcu_read_lock() is held.
  */
-
 #define list_for_each_entry_rcu(pos, head, member)                             \
        for (pos = list_entry(rcu_dereference((head)->next), typeof(*pos), member);     \
             &pos->member != (head);                                    \