+// SPDX-FileCopyrightText: 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+// SPDX-FileCopyrightText: 2009 Paul E. McKenney, IBM Corporation.
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
/*
- * urcu.c
- *
* Userspace RCU library
*
- * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
- *
- * 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.
*/
#include <poll.h>
#include <urcu/config.h>
+#include <urcu/annotate.h>
#include <urcu/assert.h>
#include <urcu/arch.h>
#include <urcu/wfcqueue.h>
static int init_done;
void __attribute__((constructor)) rcu_init(void);
-void __attribute__((destructor)) rcu_exit(void);
static DEFINE_URCU_TLS(int, rcu_signal_was_blocked);
#endif
+void __attribute__((destructor)) rcu_exit(void);
+static void urcu_call_rcu_exit(void);
+
/*
* rcu_gp_lock ensures mutual exclusion between threads calling
* synchronize_rcu().
*/
static void wait_for_readers(struct cds_list_head *input_readers,
struct cds_list_head *cur_snap_readers,
- struct cds_list_head *qsreaders)
+ struct cds_list_head *qsreaders,
+ cmm_annotate_t *group)
{
unsigned int wait_loops = 0;
struct urcu_reader *index, *tmp;
}
cds_list_for_each_entry_safe(index, tmp, input_readers, node) {
- switch (urcu_common_reader_state(&rcu_gp, &index->ctr)) {
+ switch (urcu_common_reader_state(&rcu_gp, &index->ctr, group)) {
case URCU_READER_ACTIVE_CURRENT:
if (cur_snap_readers) {
cds_list_move(&index->node,
void synchronize_rcu(void)
{
+ cmm_annotate_define(acquire_group);
+ cmm_annotate_define(release_group);
CDS_LIST_HEAD(cur_snap_readers);
CDS_LIST_HEAD(qsreaders);
DEFINE_URCU_WAIT_NODE(wait, URCU_WAIT_WAITING);
* queue before their insertion into the wait queue.
*/
if (urcu_wait_add(&gp_waiters, &wait) != 0) {
- /* Not first in queue: will be awakened by another thread. */
+ /*
+ * Not first in queue: will be awakened by another thread.
+ * Implies a memory barrier after grace period.
+ */
urcu_adaptative_busy_wait(&wait);
- /* Order following memory accesses after grace period. */
- cmm_smp_mb();
return;
}
/* We won't need to wake ourself up */
*/
/* Write new ptr before changing the qparity */
smp_mb_master();
+ cmm_annotate_group_mb_release(&release_group);
/*
* Wait for readers to observe original parity or be quiescent.
* wait_for_readers() can release and grab again rcu_registry_lock
* internally.
*/
- wait_for_readers(®istry, &cur_snap_readers, &qsreaders);
+ wait_for_readers(®istry, &cur_snap_readers, &qsreaders, &acquire_group);
/*
* Must finish waiting for quiescent state for original parity before
cmm_smp_mb();
/* Switch parity: 0 -> 1, 1 -> 0 */
- CMM_STORE_SHARED(rcu_gp.ctr, rcu_gp.ctr ^ URCU_GP_CTR_PHASE);
+ cmm_annotate_group_mem_release(&release_group, &rcu_gp.ctr);
+ uatomic_store(&rcu_gp.ctr, rcu_gp.ctr ^ URCU_GP_CTR_PHASE, CMM_RELAXED);
/*
* Must commit rcu_gp.ctr update to memory before waiting for quiescent
* wait_for_readers() can release and grab again rcu_registry_lock
* internally.
*/
- wait_for_readers(&cur_snap_readers, NULL, &qsreaders);
+ wait_for_readers(&cur_snap_readers, NULL, &qsreaders, &acquire_group);
/*
* Put quiescent reader list back into registry.
* iterates on reader threads.
*/
smp_mb_master();
+ cmm_annotate_group_mb_acquire(&acquire_group);
out:
mutex_unlock(&rcu_registry_lock);
mutex_unlock(&rcu_gp_lock);
urcu_die(errno);
}
+/*
+ * Don't unregister the SIGRCU signal handler anymore, because
+ * call_rcu threads could still be using it shortly before the
+ * application exits.
+ * Assertion disabled because call_rcu threads are now rcu
+ * readers, and left running at exit.
+ * urcu_posix_assert(cds_list_empty(®istry));
+ */
+
+#endif /* #ifdef RCU_SIGNAL */
+
void rcu_exit(void)
{
- /*
- * Don't unregister the SIGRCU signal handler anymore, because
- * call_rcu threads could still be using it shortly before the
- * application exits.
- * Assertion disabled because call_rcu threads are now rcu
- * readers, and left running at exit.
- * urcu_posix_assert(cds_list_empty(®istry));
- */
+ urcu_call_rcu_exit();
}
-#endif /* #ifdef RCU_SIGNAL */
-
DEFINE_RCU_FLAVOR(rcu_flavor);
#include "urcu-call-rcu-impl.h"
#include "urcu-defer-impl.h"
+#include "urcu-poll-impl.h"
projects / userspace-rcu.git / blobdiff