nobase_dist_include_HEADERS = urcu/compiler.h urcu/hlist.h urcu/list.h \
urcu/rculist.h urcu/rcuhlist.h urcu/system.h urcu/urcu-futex.h \
urcu/uatomic_generic.h urcu/arch_generic.h urcu/wfstack.h \
- urcu/wfqueue.h urcu/rculfstack.h urcu/rculfqueue.h
+ urcu/wfqueue.h urcu/rculfstack.h urcu/rculfqueue.h \
+ urcu/wfqueue-static.h urcu/wfstack-static.h \
+ urcu/rculfqueue-static.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 \
endif
lib_LTLIBRARIES = liburcu.la liburcu-qsbr.la liburcu-mb.la liburcu-signal.la \
- liburcu-bp.la liburcu-defer.la libwfqueue.la libwfstack.la
+ liburcu-bp.la liburcu-defer.la libwfqueue.la libwfstack.la \
+ librculfqueue.la
liburcu_la_SOURCES = urcu.c urcu-pointer.c $(COMPAT)
libwfqueue_la_SOURCES = wfqueue.c $(COMPAT)
libwfstack_la_SOURCES = wfstack.c $(COMPAT)
+librculfqueue_la_SOURCES = rculfqueue.c $(COMPAT)
--- /dev/null
+/*
+ * rculfqueue.c
+ *
+ * Userspace RCU library - Lock-Free RCU Queue
+ *
+ * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * 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
+ */
+
+/* Use the urcu symbols to select the appropriate rcu flavor at link time */
+#include "urcu.h"
+/* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
+#include "urcu/rculfqueue.h"
+#include "urcu/rculfqueue-static.h"
+
+/*
+ * library wrappers to be used by non-LGPL compatible source code.
+ */
+
+void rcu_lfq_node_init(struct rcu_lfq_node *node)
+{
+ _rcu_lfq_node_init(node);
+}
+
+void rcu_lfq_init(struct rcu_lfq_queue *q)
+{
+ _rcu_lfq_init(q);
+}
+
+void rcu_lfq_enqueue(struct rcu_lfq_queue *q, struct rcu_lfq_node *node)
+{
+ _rcu_lfq_enqueue(q, node);
+}
+
+struct rcu_lfq_node *
+rcu_lfq_dequeue(struct rcu_lfq_queue *q, void (*release)(struct urcu_ref *))
+{
+ return _rcu_lfq_dequeue(q, release);
+}
test_uatomic test_urcu_assign test_urcu_assign_dynamic_link \
test_urcu_bp test_urcu_bp_dynamic_link test_cycles_per_loop \
test_urcu_lfq test_urcu_wfq test_urcu_lfs test_urcu_wfs \
- test_urcu_wfq_dynlink test_urcu_wfs_dynlink
+ test_urcu_wfq_dynlink test_urcu_wfs_dynlink \
+ test_urcu_lfq_dynlink
noinst_HEADERS = rcutorture.h
if COMPAT_ARCH
URCU_BP_LIB=$(top_builddir)/liburcu-bp.la
WFQUEUE_LIB=$(top_builddir)/libwfqueue.la
WFSTACK_LIB=$(top_builddir)/libwfstack.la
+RCULFQUEUE_LIB=$(top_builddir)/librculfqueue.la
EXTRA_DIST = $(top_srcdir)/tests/api_*.h
test_urcu_bp_dynamic_link_CFLAGS = -DDYNAMIC_LINK_TEST $(AM_CFLAGS)
test_urcu_lfq_SOURCES = test_urcu_lfq.c $(URCU_DEFER)
+test_urcu_lfq_dynlink_SOURCES = test_urcu_lfq.c $(URCU_DEFER)
+test_urcu_lfq_dynlink_CFLAGS = -DDYNAMIC_LINK_TEST $(AM_CFLAGS)
+test_urcu_lfq_dynlink_LDADD = $(RCULFQUEUE_LIB)
+
test_urcu_wfq_SOURCES = test_urcu_wfq.c
test_urcu_wfq_dynlink_SOURCES = test_urcu_wfq.c
test_urcu_wfq_dynlink_CFLAGS = -DDYNAMIC_LINK_TEST $(AM_CFLAGS)
test_urcu_wfq_dynlink_LDADD = $(WFQUEUE_LIB)
+
test_urcu_lfs_SOURCES = test_urcu_lfs.c $(URCU_DEFER)
+
test_urcu_wfs_SOURCES = test_urcu_wfs.c
test_urcu_wfs_dynlink_SOURCES = test_urcu_wfs.c
test_urcu_wfs_dynlink_CFLAGS = -DDYNAMIC_LINK_TEST $(AM_CFLAGS)
--- /dev/null
+#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/urcu_ref.h>
+#include <urcu/uatomic_arch.h>
+#include <assert.h>
+/* A urcu implementation header should be already included. */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Lock-free RCU queue using reference counting. Enqueue and dequeue operations
+ * hold a RCU read lock to deal with cmpxchg ABA problem. This implementation
+ * keeps a dummy head node to ensure we can always update the queue locklessly.
+ * Given that this is a queue, the dummy head node must always advance as we
+ * dequeue entries. Therefore, we keep a reference count on each entry we are
+ * dequeueing, so they can be kept as dummy head node until the next dequeue, at
+ * which point their reference count will be decremented.
+ */
+
+#define URCU_LFQ_PERMANENT_REF 128
+
+void _rcu_lfq_node_init(struct rcu_lfq_node *node)
+{
+ node->next = NULL;
+ urcu_ref_init(&node->ref);
+}
+
+void _rcu_lfq_init(struct rcu_lfq_queue *q)
+{
+ _rcu_lfq_node_init(&q->init);
+ /* Make sure the initial node is never freed. */
+ urcu_ref_set(&q->init.ref, URCU_LFQ_PERMANENT_REF);
+ q->head = q->tail = &q->init;
+}
+
+void _rcu_lfq_enqueue(struct rcu_lfq_queue *q, struct rcu_lfq_node *node)
+{
+ urcu_ref_get(&node->ref);
+
+ /*
+ * uatomic_cmpxchg() implicit memory barrier orders earlier stores to
+ * node before publication.
+ */
+
+ for (;;) {
+ struct rcu_lfq_node *tail, *next;
+
+ rcu_read_lock();
+ tail = rcu_dereference(q->tail);
+ /*
+ * Typically expect tail->next to be NULL.
+ */
+ next = uatomic_cmpxchg(&tail->next, NULL, node);
+ 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).
+ */
+ uatomic_cmpxchg(&q->tail, tail, node);
+ rcu_read_unlock();
+ return;
+ } else {
+ /*
+ * Failure to append to current tail. Help moving tail
+ * further and retry.
+ */
+ uatomic_cmpxchg(&q->tail, tail, next);
+ rcu_read_unlock();
+ continue;
+ }
+ }
+}
+
+/*
+ * The entry returned by dequeue must be taken care of by doing a urcu_ref_put,
+ * which calls the release primitive when the reference count drops to zero. A
+ * grace period must be waited after execution of the release callback before
+ * performing the actual memory reclamation or modifying the rcu_lfq_node
+ * structure.
+ * In other words, the entry lfq node returned by dequeue must not be
+ * modified/re-used/freed until the reference count reaches zero and a grace
+ * period has elapsed (after the refcount reached 0).
+ */
+struct rcu_lfq_node *
+_rcu_lfq_dequeue(struct rcu_lfq_queue *q, void (*release)(struct urcu_ref *))
+{
+ for (;;) {
+ struct rcu_lfq_node *head, *next;
+
+ rcu_read_lock();
+ head = rcu_dereference(q->head);
+ next = rcu_dereference(head->next);
+ if (next) {
+ if (uatomic_cmpxchg(&q->head, head, next) == head) {
+ rcu_read_unlock();
+ urcu_ref_put(&head->ref, release);
+ return next;
+ } else {
+ /* Concurrently pushed, retry */
+ rcu_read_unlock();
+ continue;
+ }
+ } else {
+ /* Empty */
+ rcu_read_unlock();
+ return NULL;
+ }
+ }
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _URCU_RCULFQUEUE_STATIC_H */
extern "C" {
#endif
-#if (!defined(_GNU_SOURCE) && !defined(_LGPL_SOURCE))
-#error "Dynamic loader LGPL wrappers not implemented yet"
-#endif
-
/*
* Lock-free RCU queue using reference counting. Enqueue and dequeue operations
* hold a RCU read lock to deal with cmpxchg ABA problem. This implementation
* which point their reference count will be decremented.
*/
-#define URCU_LFQ_PERMANENT_REF 128
-
struct rcu_lfq_node {
struct rcu_lfq_node *next;
struct urcu_ref ref;
struct rcu_lfq_node init; /* Dummy initialization node */
};
-void rcu_lfq_node_init(struct rcu_lfq_node *node)
-{
- node->next = NULL;
- urcu_ref_init(&node->ref);
-}
-
-void rcu_lfq_init(struct rcu_lfq_queue *q)
-{
- rcu_lfq_node_init(&q->init);
- /* Make sure the initial node is never freed. */
- urcu_ref_set(&q->init.ref, URCU_LFQ_PERMANENT_REF);
- q->head = q->tail = &q->init;
-}
+#ifdef _LGPL_SOURCE
-void rcu_lfq_enqueue(struct rcu_lfq_queue *q, struct rcu_lfq_node *node)
-{
- urcu_ref_get(&node->ref);
+#include <urcu/rculfqueue-static.h>
- /*
- * uatomic_cmpxchg() implicit memory barrier orders earlier stores to
- * node before publication.
- */
+#define rcu_lfq_node_init _rcu_lfq_node_init
+#define rcu_lfq_init _rcu_lfq_init
+#define rcu_lfq_enqueue _rcu_lfq_enqueue
+#define rcu_lfq_dequeue _rcu_lfq_dequeue
- for (;;) {
- struct rcu_lfq_node *tail, *next;
+#else /* !_LGPL_SOURCE */
- rcu_read_lock();
- tail = rcu_dereference(q->tail);
- /*
- * Typically expect tail->next to be NULL.
- */
- next = uatomic_cmpxchg(&tail->next, NULL, node);
- 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).
- */
- uatomic_cmpxchg(&q->tail, tail, node);
- rcu_read_unlock();
- return;
- } else {
- /*
- * Failure to append to current tail. Help moving tail
- * further and retry.
- */
- uatomic_cmpxchg(&q->tail, tail, next);
- rcu_read_unlock();
- continue;
- }
- }
-}
+extern void rcu_lfq_node_init(struct rcu_lfq_node *node);
+extern void rcu_lfq_init(struct rcu_lfq_queue *q);
+extern void rcu_lfq_enqueue(struct rcu_lfq_queue *q, struct rcu_lfq_node *node);
/*
* The entry returned by dequeue must be taken care of by doing a urcu_ref_put,
* modified/re-used/freed until the reference count reaches zero and a grace
* period has elapsed (after the refcount reached 0).
*/
-struct rcu_lfq_node *
-rcu_lfq_dequeue(struct rcu_lfq_queue *q, void (*release)(struct urcu_ref *))
-{
- for (;;) {
- struct rcu_lfq_node *head, *next;
+extern struct rcu_lfq_node *
+rcu_lfq_dequeue(struct rcu_lfq_queue *q, void (*release)(struct urcu_ref *));
- rcu_read_lock();
- head = rcu_dereference(q->head);
- next = rcu_dereference(head->next);
- if (next) {
- if (uatomic_cmpxchg(&q->head, head, next) == head) {
- rcu_read_unlock();
- urcu_ref_put(&head->ref, release);
- return next;
- } else {
- /* Concurrently pushed, retry */
- rcu_read_unlock();
- continue;
- }
- } else {
- /* Empty */
- rcu_read_unlock();
- return NULL;
- }
- }
-}
+#endif /* !_LGPL_SOURCE */
#ifdef __cplusplus
}
projects / userspace-rcu.git / commitdiff
