endif
lib_LTLIBRARIES = liburcu.la liburcu-qsbr.la liburcu-mb.la liburcu-signal.la \
- liburcu-bp.la liburcu-defer.la liburcu-call.la \
+ liburcu-bp.la liburcu-defer.la \
libwfqueue.la libwfstack.la librculfqueue.la librculfstack.la
liburcu_la_SOURCES = urcu.c urcu-pointer.c $(COMPAT)
liburcu_bp_la_SOURCES = urcu-bp.c urcu-pointer.c $(COMPAT)
-liburcu_call_la_SOURCES = urcu-call-rcu.c $(COMPAT)
liburcu_defer_la_SOURCES = urcu-defer.c $(COMPAT)
libwfqueue_la_SOURCES = wfqueue.c $(COMPAT)
COMPAT+=$(top_srcdir)/compat_futex.c
endif
-URCU=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
-URCU_QSBR=$(top_srcdir)/urcu-qsbr.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
+URCU=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
+URCU_QSBR=$(top_srcdir)/urcu-qsbr.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
# URCU_MB uses urcu.c but -DRCU_MB must be defined
-URCU_MB=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
+URCU_MB=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
# URCU_SIGNAL uses urcu.c but -DRCU_SIGNAL must be defined
-URCU_SIGNAL=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
-URCU_BP=$(top_srcdir)/urcu-bp.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
-URCU_DEFER=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-defer.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
+URCU_SIGNAL=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
+URCU_BP=$(top_srcdir)/urcu-bp.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
+URCU_DEFER=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-defer.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
URCU_LIB=$(top_builddir)/liburcu.la
URCU_QSBR_LIB=$(top_builddir)/liburcu-qsbr.la
URCU_MB_LIB=$(top_builddir)/liburcu-mb.la
URCU_SIGNAL_LIB=$(top_builddir)/liburcu-signal.la
URCU_BP_LIB=$(top_builddir)/liburcu-bp.la
-URCU_CALL_LIB=$(top_builddir)/liburcu-call.la
WFQUEUE_LIB=$(top_builddir)/libwfqueue.la
WFSTACK_LIB=$(top_builddir)/libwfstack.la
RCULFQUEUE_LIB=$(top_builddir)/librculfqueue.la
rcutorture_urcu_SOURCES = urcutorture.c
-rcutorture_urcu_CFLAGS = -DTORTURE_URCU $(AM_CFLAGS)
-rcutorture_urcu_LDADD = $(URCU) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
+rcutorture_urcu_CFLAGS = -DRCU_MEMBARRIER $(AM_CFLAGS)
+rcutorture_urcu_LDADD = $(URCU) $(WFQUEUE_LIB)
rcutorture_urcu_mb_SOURCES = urcutorture.c
-rcutorture_urcu_mb_CFLAGS = -DTORTURE_URCU_MB $(AM_CFLAGS)
-rcutorture_urcu_mb_LDADD = $(URCU_MB_LIB) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
+rcutorture_urcu_mb_CFLAGS = -DRCU_MB $(AM_CFLAGS)
+rcutorture_urcu_mb_LDADD = $(URCU_MB_LIB) $(WFQUEUE_LIB)
rcutorture_qsbr_SOURCES = urcutorture.c
-rcutorture_qsbr_CFLAGS = -DTORTURE_QSBR $(AM_CFLAGS)
-rcutorture_qsbr_LDADD = $(URCU_QSBR_LIB) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
+rcutorture_qsbr_CFLAGS = -DRCU_QSBR $(AM_CFLAGS)
+rcutorture_qsbr_LDADD = $(URCU_QSBR_LIB) $(WFQUEUE_LIB)
rcutorture_urcu_signal_SOURCES = urcutorture.c
-rcutorture_urcu_signal_CFLAGS = -DTORTURE_URCU_SIGNAL $(AM_CFLAGS)
-rcutorture_urcu_signal_LDADD = $(URCU_SIGNAL_LIB) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
+rcutorture_urcu_signal_CFLAGS = -DRCU_SIGNAL $(AM_CFLAGS)
+rcutorture_urcu_signal_LDADD = $(URCU_SIGNAL_LIB) $(WFQUEUE_LIB)
rcutorture_urcu_bp_SOURCES = urcutorture.c
-rcutorture_urcu_bp_CFLAGS = -DTORTURE_URCU_BP $(AM_CFLAGS)
-rcutorture_urcu_bp_LDADD = $(URCU_BP_LIB) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
+rcutorture_urcu_bp_CFLAGS = -DRCU_BP $(AM_CFLAGS)
+rcutorture_urcu_bp_LDADD = $(URCU_BP_LIB) $(WFQUEUE_LIB)
test_mutex_SOURCES = test_mutex.c $(URCU)
*/
#include <stdlib.h>
-#include "../urcu-call-rcu.h"
DEFINE_PER_THREAD(long long, n_reads_pt);
DEFINE_PER_THREAD(long long, n_updates_pt);
#include "api.h"
#define _LGPL_SOURCE
-#ifdef TORTURE_RCU_MEMBARRIER
-#define RCU_MEMBARRIER
+#ifdef RCU_MEMBARRIER
#include <urcu.h>
#endif
-#ifdef TORTURE_URCU_SIGNAL
-#define RCU_SIGNAL
+#ifdef RCU_SIGNAL
#include <urcu.h>
#endif
-#ifdef TORTURE_URCU_MB
-#define RCU_MB
+#ifdef RCU_MB
#include <urcu.h>
#endif
-#ifdef TORTURE_QSBR
+#ifdef RCU_QSBR
#include <urcu-qsbr.h>
#endif
-#ifdef TORTURE_URCU_BP
+#ifdef RCU_BP
#include <urcu-bp.h>
#endif
--- /dev/null
+#ifndef _URCU_BP_MAP_H
+#define _URCU_BP_MAP_H
+
+/*
+ * urcu-map.h
+ *
+ * Userspace RCU header -- name mapping to allow multiple flavors to be
+ * used in the same executable.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
+ *
+ * LGPL-compatible code should include this header with :
+ *
+ * #define _LGPL_SOURCE
+ * #include <urcu.h>
+ *
+ * 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.
+ */
+
+/* Mapping macros to allow multiple flavors in a single binary. */
+
+#define rcu_read_lock rcu_read_lock_bp
+#define _rcu_read_lock _rcu_read_lock_bp
+#define rcu_read_unlock rcu_read_unlock_bp
+#define _rcu_read_unlock _rcu_read_unlock_bp
+#define rcu_register_thread rcu_register_thread_bp
+#define rcu_unregister_thread rcu_unregister_thread_bp
+#define rcu_init rcu_init_bp
+#define rcu_exit rcu_exit_bp
+#define synchronize_rcu synchronize_rcu_bp
+#define rcu_reader rcu_reader_bp
+#define rcu_gp_ctr rcu_gp_ctr_bp
+
+#define get_cpu_call_rcu_data get_cpu_call_rcu_data_bp
+#define get_call_rcu_thread get_call_rcu_thread_bp
+#define create_call_rcu_data create_call_rcu_data_bp
+#define set_cpu_call_rcu_data set_cpu_call_rcu_data_bp
+#define get_default_call_rcu_data get_default_call_rcu_data_bp
+#define get_call_rcu_data get_call_rcu_data_bp
+#define get_thread_call_rcu_data get_thread_call_rcu_data_bp
+#define set_thread_call_rcu_data set_thread_call_rcu_data_bp
+#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_bp
+#define free_all_cpu_call_rcu_data free_all_cpu_call_rcu_data_bp
+#define call_rcu call_rcu_bp
+
+#endif /* _URCU_BP_MAP_H */
#include <unistd.h>
#include <sys/mman.h>
+#include "urcu-bp-map.h"
+
#include "urcu-bp-static.h"
/* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
#include "urcu-bp.h"
ret = pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
assert(!ret);
}
+
+#include "urcu-call-rcu-impl.h"
extern "C" {
#endif
+#include "urcu-bp-map.h"
+
/*
* Important !
*
*
* Mark the beginning and end of a read-side critical section.
*/
-#define rcu_read_lock() _rcu_read_lock()
-#define rcu_read_unlock() _rcu_read_unlock()
+#define rcu_read_lock_bp() _rcu_read_lock()
+#define rcu_read_unlock_bp() _rcu_read_unlock()
#else /* !_LGPL_SOURCE */
}
#endif
+#include "urcu-call-rcu.h"
+
#endif /* _URCU_BP_H */
--- /dev/null
+/*
+ * urcu-call-rcu.c
+ *
+ * Userspace RCU library - batch memory reclamation with kernel API
+ *
+ * Copyright (c) 2010 Paul E. McKenney <paulmck@linux.vnet.ibm.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
+ */
+
+#include <stdio.h>
+#include <pthread.h>
+#include <signal.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <poll.h>
+#include <sys/time.h>
+#include <syscall.h>
+#include <unistd.h>
+
+#include "config.h"
+#include "urcu/wfqueue.h"
+#include "urcu-call-rcu.h"
+#include "urcu-pointer.h"
+#include "urcu/list.h"
+
+/* Data structure that identifies a call_rcu thread. */
+
+struct call_rcu_data {
+ struct cds_wfq_queue cbs;
+ unsigned long flags;
+ pthread_mutex_t mtx;
+ pthread_cond_t cond;
+ unsigned long qlen;
+ pthread_t tid;
+ struct cds_list_head list;
+} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
+
+/*
+ * List of all call_rcu_data structures to keep valgrind happy.
+ * Protected by call_rcu_mutex.
+ */
+
+CDS_LIST_HEAD(call_rcu_data_list);
+
+/* Link a thread using call_rcu() to its call_rcu thread. */
+
+static __thread struct call_rcu_data *thread_call_rcu_data;
+
+/* Guard call_rcu thread creation. */
+
+static pthread_mutex_t call_rcu_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+/* If a given thread does not have its own call_rcu thread, this is default. */
+
+static struct call_rcu_data *default_call_rcu_data;
+
+/*
+ * If the sched_getcpu() and sysconf(_SC_NPROCESSORS_CONF) calls are
+ * available, then we can have call_rcu threads assigned to individual
+ * CPUs rather than only to specific threads.
+ */
+
+#if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF)
+
+/*
+ * Pointer to array of pointers to per-CPU call_rcu_data structures
+ * and # CPUs.
+ */
+
+static struct call_rcu_data **per_cpu_call_rcu_data;
+static long maxcpus;
+
+/* Allocate the array if it has not already been allocated. */
+
+static void alloc_cpu_call_rcu_data(void)
+{
+ struct call_rcu_data **p;
+ static int warned = 0;
+
+ if (maxcpus != 0)
+ return;
+ maxcpus = sysconf(_SC_NPROCESSORS_CONF);
+ if (maxcpus <= 0) {
+ return;
+ }
+ p = malloc(maxcpus * sizeof(*per_cpu_call_rcu_data));
+ if (p != NULL) {
+ memset(p, '\0', maxcpus * sizeof(*per_cpu_call_rcu_data));
+ per_cpu_call_rcu_data = p;
+ } else {
+ if (!warned) {
+ fprintf(stderr, "[error] liburcu: unable to allocate per-CPU pointer array\n");
+ }
+ warned = 1;
+ }
+}
+
+#else /* #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */
+
+static const struct call_rcu_data **per_cpu_call_rcu_data = NULL;
+static const long maxcpus = -1;
+
+static void alloc_cpu_call_rcu_data(void)
+{
+}
+
+static int sched_getcpu(void)
+{
+ return -1;
+}
+
+#endif /* #else #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */
+
+/* Acquire the specified pthread mutex. */
+
+static void call_rcu_lock(pthread_mutex_t *pmp)
+{
+ if (pthread_mutex_lock(pmp) != 0) {
+ perror("pthread_mutex_lock");
+ exit(-1);
+ }
+}
+
+/* Release the specified pthread mutex. */
+
+static void call_rcu_unlock(pthread_mutex_t *pmp)
+{
+ if (pthread_mutex_unlock(pmp) != 0) {
+ perror("pthread_mutex_unlock");
+ exit(-1);
+ }
+}
+
+/* This is the code run by each call_rcu thread. */
+
+static void *call_rcu_thread(void *arg)
+{
+ unsigned long cbcount;
+ struct cds_wfq_node *cbs;
+ struct cds_wfq_node **cbs_tail;
+ struct call_rcu_data *crdp = (struct call_rcu_data *)arg;
+ struct rcu_head *rhp;
+
+ thread_call_rcu_data = crdp;
+ for (;;) {
+ if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
+ while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
+ poll(NULL, 0, 1);
+ _CMM_STORE_SHARED(crdp->cbs.head, NULL);
+ cbs_tail = (struct cds_wfq_node **)
+ uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
+ synchronize_rcu();
+ cbcount = 0;
+ do {
+ while (cbs->next == NULL &&
+ &cbs->next != cbs_tail)
+ poll(NULL, 0, 1);
+ if (cbs == &crdp->cbs.dummy) {
+ cbs = cbs->next;
+ continue;
+ }
+ rhp = (struct rcu_head *)cbs;
+ cbs = cbs->next;
+ rhp->func(rhp);
+ cbcount++;
+ } while (cbs != NULL);
+ uatomic_sub(&crdp->qlen, cbcount);
+ }
+ if (crdp->flags & URCU_CALL_RCU_STOP)
+ break;
+ if (crdp->flags & URCU_CALL_RCU_RT)
+ poll(NULL, 0, 10);
+ else {
+ call_rcu_lock(&crdp->mtx);
+ _CMM_STORE_SHARED(crdp->flags,
+ crdp->flags & ~URCU_CALL_RCU_RUNNING);
+ if (&crdp->cbs.head ==
+ _CMM_LOAD_SHARED(crdp->cbs.tail) &&
+ pthread_cond_wait(&crdp->cond, &crdp->mtx) != 0) {
+ perror("pthread_cond_wait");
+ exit(-1);
+ }
+ _CMM_STORE_SHARED(crdp->flags,
+ crdp->flags | URCU_CALL_RCU_RUNNING);
+ poll(NULL, 0, 10);
+ call_rcu_unlock(&crdp->mtx);
+ }
+ }
+ call_rcu_lock(&crdp->mtx);
+ crdp->flags |= URCU_CALL_RCU_STOPPED;
+ call_rcu_unlock(&crdp->mtx);
+ return NULL;
+}
+
+/*
+ * Create both a call_rcu thread and the corresponding call_rcu_data
+ * structure, linking the structure in as specified. Caller must hold
+ * call_rcu_mutex.
+ */
+
+static void call_rcu_data_init(struct call_rcu_data **crdpp,
+ unsigned long flags)
+{
+ struct call_rcu_data *crdp;
+
+ crdp = malloc(sizeof(*crdp));
+ if (crdp == NULL) {
+ fprintf(stderr, "Out of memory.\n");
+ exit(-1);
+ }
+ memset(crdp, '\0', sizeof(*crdp));
+ cds_wfq_init(&crdp->cbs);
+ crdp->qlen = 0;
+ if (pthread_mutex_init(&crdp->mtx, NULL) != 0) {
+ perror("pthread_mutex_init");
+ exit(-1);
+ }
+ if (pthread_cond_init(&crdp->cond, NULL) != 0) {
+ perror("pthread_cond_init");
+ exit(-1);
+ }
+ crdp->flags = flags | URCU_CALL_RCU_RUNNING;
+ cds_list_add(&crdp->list, &call_rcu_data_list);
+ cmm_smp_mb(); /* Structure initialized before pointer is planted. */
+ *crdpp = crdp;
+ if (pthread_create(&crdp->tid, NULL, call_rcu_thread, crdp) != 0) {
+ perror("pthread_create");
+ exit(-1);
+ }
+}
+
+/*
+ * Return a pointer to the call_rcu_data structure for the specified
+ * CPU, returning NULL if there is none. We cannot automatically
+ * created it because the platform we are running on might not define
+ * sched_getcpu().
+ */
+
+struct call_rcu_data *get_cpu_call_rcu_data(int cpu)
+{
+ static int warned = 0;
+
+ if (per_cpu_call_rcu_data == NULL)
+ return NULL;
+ if (!warned && maxcpus > 0 && (cpu < 0 || maxcpus <= cpu)) {
+ fprintf(stderr, "[error] liburcu: get CPU # out of range\n");
+ warned = 1;
+ }
+ if (cpu < 0 || maxcpus <= cpu)
+ return NULL;
+ return per_cpu_call_rcu_data[cpu];
+}
+
+/*
+ * Return the tid corresponding to the call_rcu thread whose
+ * call_rcu_data structure is specified.
+ */
+
+pthread_t get_call_rcu_thread(struct call_rcu_data *crdp)
+{
+ return crdp->tid;
+}
+
+/*
+ * Create a call_rcu_data structure (with thread) and return a pointer.
+ */
+
+static struct call_rcu_data *__create_call_rcu_data(unsigned long flags)
+{
+ struct call_rcu_data *crdp;
+
+ call_rcu_data_init(&crdp, flags);
+ return crdp;
+}
+
+struct call_rcu_data *create_call_rcu_data(unsigned long flags)
+{
+ struct call_rcu_data *crdp;
+
+ call_rcu_lock(&call_rcu_mutex);
+ crdp = __create_call_rcu_data(flags);
+ call_rcu_unlock(&call_rcu_mutex);
+ return crdp;
+}
+
+/*
+ * Set the specified CPU to use the specified call_rcu_data structure.
+ *
+ * Use NULL to remove a CPU's call_rcu_data structure, but it is
+ * the caller's responsibility to dispose of the removed structure.
+ * Use get_cpu_call_rcu_data() to obtain a pointer to the old structure
+ * (prior to NULLing it out, of course).
+ */
+
+int set_cpu_call_rcu_data(int cpu, struct call_rcu_data *crdp)
+{
+ int warned = 0;
+
+ call_rcu_lock(&call_rcu_mutex);
+ if (cpu < 0 || maxcpus <= cpu) {
+ if (!warned) {
+ fprintf(stderr, "[error] liburcu: set CPU # out of range\n");
+ warned = 1;
+ }
+ call_rcu_unlock(&call_rcu_mutex);
+ errno = EINVAL;
+ return -EINVAL;
+ }
+ alloc_cpu_call_rcu_data();
+ call_rcu_unlock(&call_rcu_mutex);
+ if (per_cpu_call_rcu_data == NULL) {
+ errno = ENOMEM;
+ return -ENOMEM;
+ }
+ per_cpu_call_rcu_data[cpu] = crdp;
+ return 0;
+}
+
+/*
+ * Return a pointer to the default call_rcu_data structure, creating
+ * one if need be. Because we never free call_rcu_data structures,
+ * we don't need to be in an RCU read-side critical section.
+ */
+
+struct call_rcu_data *get_default_call_rcu_data(void)
+{
+ if (default_call_rcu_data != NULL)
+ return rcu_dereference(default_call_rcu_data);
+ call_rcu_lock(&call_rcu_mutex);
+ if (default_call_rcu_data != NULL) {
+ call_rcu_unlock(&call_rcu_mutex);
+ return default_call_rcu_data;
+ }
+ call_rcu_data_init(&default_call_rcu_data, 0);
+ call_rcu_unlock(&call_rcu_mutex);
+ return default_call_rcu_data;
+}
+
+/*
+ * Return the call_rcu_data structure that applies to the currently
+ * running thread. Any call_rcu_data structure assigned specifically
+ * to this thread has first priority, followed by any call_rcu_data
+ * structure assigned to the CPU on which the thread is running,
+ * followed by the default call_rcu_data structure. If there is not
+ * yet a default call_rcu_data structure, one will be created.
+ */
+struct call_rcu_data *get_call_rcu_data(void)
+{
+ int curcpu;
+ static int warned = 0;
+
+ if (thread_call_rcu_data != NULL)
+ return thread_call_rcu_data;
+ if (maxcpus <= 0)
+ return get_default_call_rcu_data();
+ curcpu = sched_getcpu();
+ if (!warned && (curcpu < 0 || maxcpus <= curcpu)) {
+ fprintf(stderr, "[error] liburcu: gcrd CPU # out of range\n");
+ warned = 1;
+ }
+ if (curcpu >= 0 && maxcpus > curcpu &&
+ per_cpu_call_rcu_data != NULL &&
+ per_cpu_call_rcu_data[curcpu] != NULL)
+ return per_cpu_call_rcu_data[curcpu];
+ return get_default_call_rcu_data();
+}
+
+/*
+ * Return a pointer to this task's call_rcu_data if there is one.
+ */
+
+struct call_rcu_data *get_thread_call_rcu_data(void)
+{
+ return thread_call_rcu_data;
+}
+
+/*
+ * Set this task's call_rcu_data structure as specified, regardless
+ * of whether or not this task already had one. (This allows switching
+ * to and from real-time call_rcu threads, for example.)
+ *
+ * Use NULL to remove a thread's call_rcu_data structure, but it is
+ * the caller's responsibility to dispose of the removed structure.
+ * Use get_thread_call_rcu_data() to obtain a pointer to the old structure
+ * (prior to NULLing it out, of course).
+ */
+
+void set_thread_call_rcu_data(struct call_rcu_data *crdp)
+{
+ thread_call_rcu_data = crdp;
+}
+
+/*
+ * Create a separate call_rcu thread for each CPU. This does not
+ * replace a pre-existing call_rcu thread -- use the set_cpu_call_rcu_data()
+ * function if you want that behavior.
+ */
+
+int create_all_cpu_call_rcu_data(unsigned long flags)
+{
+ int i;
+ struct call_rcu_data *crdp;
+ int ret;
+
+ call_rcu_lock(&call_rcu_mutex);
+ alloc_cpu_call_rcu_data();
+ call_rcu_unlock(&call_rcu_mutex);
+ if (maxcpus <= 0) {
+ errno = EINVAL;
+ return -EINVAL;
+ }
+ if (per_cpu_call_rcu_data == NULL) {
+ errno = ENOMEM;
+ return -ENOMEM;
+ }
+ for (i = 0; i < maxcpus; i++) {
+ call_rcu_lock(&call_rcu_mutex);
+ if (get_cpu_call_rcu_data(i)) {
+ call_rcu_unlock(&call_rcu_mutex);
+ continue;
+ }
+ crdp = __create_call_rcu_data(flags);
+ if (crdp == NULL) {
+ call_rcu_unlock(&call_rcu_mutex);
+ errno = ENOMEM;
+ return -ENOMEM;
+ }
+ call_rcu_unlock(&call_rcu_mutex);
+ if ((ret = set_cpu_call_rcu_data(i, crdp)) != 0) {
+ /* FIXME: Leaks crdp for now. */
+ return ret; /* Can happen on race. */
+ }
+ }
+ return 0;
+}
+
+/*
+ * Wake up the call_rcu thread corresponding to the specified
+ * call_rcu_data structure.
+ */
+static void wake_call_rcu_thread(struct call_rcu_data *crdp)
+{
+ if (!(_CMM_LOAD_SHARED(crdp->flags) & URCU_CALL_RCU_RT)) {
+ call_rcu_lock(&crdp->mtx);
+ if (!(_CMM_LOAD_SHARED(crdp->flags) & URCU_CALL_RCU_RUNNING)) {
+ if (pthread_cond_signal(&crdp->cond) != 0) {
+ perror("pthread_cond_signal");
+ exit(-1);
+ }
+ }
+ call_rcu_unlock(&crdp->mtx);
+ }
+}
+
+/*
+ * Schedule a function to be invoked after a following grace period.
+ * This is the only function that must be called -- the others are
+ * only present to allow applications to tune their use of RCU for
+ * maximum performance.
+ *
+ * Note that unless a call_rcu thread has not already been created,
+ * the first invocation of call_rcu() will create one. So, if you
+ * need the first invocation of call_rcu() to be fast, make sure
+ * to create a call_rcu thread first. One way to accomplish this is
+ * "get_call_rcu_data();", and another is create_all_cpu_call_rcu_data().
+ */
+
+void call_rcu(struct rcu_head *head,
+ void (*func)(struct rcu_head *head))
+{
+ struct call_rcu_data *crdp;
+
+ cds_wfq_node_init(&head->next);
+ head->func = func;
+ crdp = get_call_rcu_data();
+ cds_wfq_enqueue(&crdp->cbs, &head->next);
+ uatomic_inc(&crdp->qlen);
+ wake_call_rcu_thread(crdp);
+}
+
+/*
+ * Free up the specified call_rcu_data structure, terminating the
+ * associated call_rcu thread. The caller must have previously
+ * removed the call_rcu_data structure from per-thread or per-CPU
+ * usage. For example, set_cpu_call_rcu_data(cpu, NULL) for per-CPU
+ * call_rcu_data structures or set_thread_call_rcu_data(NULL) for
+ * per-thread call_rcu_data structures.
+ *
+ * We silently refuse to free up the default call_rcu_data structure
+ * because that is where we put any leftover callbacks. Note that
+ * the possibility of self-spawning callbacks makes it impossible
+ * to execute all the callbacks in finite time without putting any
+ * newly spawned callbacks somewhere else. The "somewhere else" of
+ * last resort is the default call_rcu_data structure.
+ *
+ * We also silently refuse to free NULL pointers. This simplifies
+ * the calling code.
+ */
+void call_rcu_data_free(struct call_rcu_data *crdp)
+{
+ struct cds_wfq_node *cbs;
+ struct cds_wfq_node **cbs_tail;
+ struct cds_wfq_node **cbs_endprev;
+
+ if (crdp == NULL || crdp == default_call_rcu_data) {
+ return;
+ }
+ if ((crdp->flags & URCU_CALL_RCU_STOPPED) == 0) {
+ call_rcu_lock(&crdp->mtx);
+ crdp->flags |= URCU_CALL_RCU_STOP;
+ call_rcu_unlock(&crdp->mtx);
+ wake_call_rcu_thread(crdp);
+ while ((crdp->flags & URCU_CALL_RCU_STOPPED) == 0)
+ poll(NULL, 0, 1);
+ }
+ if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
+ while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
+ poll(NULL, 0, 1);
+ _CMM_STORE_SHARED(crdp->cbs.head, NULL);
+ cbs_tail = (struct cds_wfq_node **)
+ uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
+ cbs_endprev = (struct cds_wfq_node **)
+ uatomic_xchg(&default_call_rcu_data, cbs_tail);
+ *cbs_endprev = cbs;
+ uatomic_add(&default_call_rcu_data->qlen,
+ uatomic_read(&crdp->qlen));
+ cds_list_del(&crdp->list);
+ free(crdp);
+ }
+}
+
+/*
+ * Clean up all the per-CPU call_rcu threads.
+ */
+void free_all_cpu_call_rcu_data(void)
+{
+ int cpu;
+ struct call_rcu_data *crdp;
+
+ if (maxcpus <= 0)
+ return;
+ for (cpu = 0; cpu < maxcpus; cpu++) {
+ crdp = get_cpu_call_rcu_data(cpu);
+ if (crdp == NULL)
+ continue;
+ set_cpu_call_rcu_data(cpu, NULL);
+ call_rcu_data_free(crdp);
+ }
+}
+
+/*
+ * Acquire the call_rcu_mutex in order to ensure that the child sees
+ * all of the call_rcu() data structures in a consistent state.
+ * Suitable for pthread_atfork() and friends.
+ */
+void call_rcu_before_fork(void)
+{
+ call_rcu_lock(&call_rcu_mutex);
+}
+
+/*
+ * Clean up call_rcu data structures in the parent of a successful fork()
+ * that is not followed by exec() in the child. Suitable for
+ * pthread_atfork() and friends.
+ */
+void call_rcu_after_fork_parent(void)
+{
+ call_rcu_unlock(&call_rcu_mutex);
+}
+
+/*
+ * Clean up call_rcu data structures in the child of a successful fork()
+ * that is not followed by exec(). Suitable for pthread_atfork() and
+ * friends.
+ */
+void call_rcu_after_fork_child(void)
+{
+ struct call_rcu_data *crdp;
+
+ /* Release the mutex. */
+ call_rcu_unlock(&call_rcu_mutex);
+
+ /*
+ * Allocate a new default call_rcu_data structure in order
+ * to get a working call_rcu thread to go with it.
+ */
+ default_call_rcu_data = NULL;
+ (void)get_default_call_rcu_data();
+
+ /* Dispose of all of the rest of the call_rcu_data structures. */
+ while (call_rcu_data_list.next != call_rcu_data_list.prev) {
+ crdp = cds_list_entry(call_rcu_data_list.prev,
+ struct call_rcu_data, list);
+ if (crdp == default_call_rcu_data)
+ crdp = cds_list_entry(crdp->list.prev,
+ struct call_rcu_data, list);
+ crdp->flags = URCU_CALL_RCU_STOPPED;
+ call_rcu_data_free(crdp);
+ }
+}
+++ /dev/null
-/*
- * urcu-call-rcu.c
- *
- * Userspace RCU library - batch memory reclamation with kernel API
- *
- * Copyright (c) 2010 Paul E. McKenney <paulmck@linux.vnet.ibm.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
- */
-
-#include <stdio.h>
-#include <pthread.h>
-#include <signal.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <poll.h>
-#include <sys/time.h>
-#include <syscall.h>
-#include <unistd.h>
-
-#include "config.h"
-#include "urcu/wfqueue.h"
-#include "urcu-call-rcu.h"
-#include "urcu-pointer.h"
-#include "urcu/list.h"
-
-/* Data structure that identifies a call_rcu thread. */
-
-struct call_rcu_data {
- struct cds_wfq_queue cbs;
- unsigned long flags;
- pthread_mutex_t mtx;
- pthread_cond_t cond;
- unsigned long qlen;
- pthread_t tid;
- struct cds_list_head list;
-} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
-
-/*
- * List of all call_rcu_data structures to keep valgrind happy.
- * Protected by call_rcu_mutex.
- */
-
-CDS_LIST_HEAD(call_rcu_data_list);
-
-/* Link a thread using call_rcu() to its call_rcu thread. */
-
-static __thread struct call_rcu_data *thread_call_rcu_data;
-
-/* Guard call_rcu thread creation. */
-
-static pthread_mutex_t call_rcu_mutex = PTHREAD_MUTEX_INITIALIZER;
-
-/* If a given thread does not have its own call_rcu thread, this is default. */
-
-static struct call_rcu_data *default_call_rcu_data;
-
-extern void synchronize_rcu(void);
-
-/*
- * If the sched_getcpu() and sysconf(_SC_NPROCESSORS_CONF) calls are
- * available, then we can have call_rcu threads assigned to individual
- * CPUs rather than only to specific threads.
- */
-
-#if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF)
-
-/*
- * Pointer to array of pointers to per-CPU call_rcu_data structures
- * and # CPUs.
- */
-
-static struct call_rcu_data **per_cpu_call_rcu_data;
-static long maxcpus;
-
-/* Allocate the array if it has not already been allocated. */
-
-static void alloc_cpu_call_rcu_data(void)
-{
- struct call_rcu_data **p;
- static int warned = 0;
-
- if (maxcpus != 0)
- return;
- maxcpus = sysconf(_SC_NPROCESSORS_CONF);
- if (maxcpus <= 0) {
- return;
- }
- p = malloc(maxcpus * sizeof(*per_cpu_call_rcu_data));
- if (p != NULL) {
- memset(p, '\0', maxcpus * sizeof(*per_cpu_call_rcu_data));
- per_cpu_call_rcu_data = p;
- } else {
- if (!warned) {
- fprintf(stderr, "[error] liburcu: unable to allocate per-CPU pointer array\n");
- }
- warned = 1;
- }
-}
-
-#else /* #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */
-
-static const struct call_rcu_data **per_cpu_call_rcu_data = NULL;
-static const long maxcpus = -1;
-
-static void alloc_cpu_call_rcu_data(void)
-{
-}
-
-static int sched_getcpu(void)
-{
- return -1;
-}
-
-#endif /* #else #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */
-
-/* Acquire the specified pthread mutex. */
-
-static void call_rcu_lock(pthread_mutex_t *pmp)
-{
- if (pthread_mutex_lock(pmp) != 0) {
- perror("pthread_mutex_lock");
- exit(-1);
- }
-}
-
-/* Release the specified pthread mutex. */
-
-static void call_rcu_unlock(pthread_mutex_t *pmp)
-{
- if (pthread_mutex_unlock(pmp) != 0) {
- perror("pthread_mutex_unlock");
- exit(-1);
- }
-}
-
-/* This is the code run by each call_rcu thread. */
-
-static void *call_rcu_thread(void *arg)
-{
- unsigned long cbcount;
- struct cds_wfq_node *cbs;
- struct cds_wfq_node **cbs_tail;
- struct call_rcu_data *crdp = (struct call_rcu_data *)arg;
- struct rcu_head *rhp;
-
- thread_call_rcu_data = crdp;
- for (;;) {
- if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
- while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
- poll(NULL, 0, 1);
- _CMM_STORE_SHARED(crdp->cbs.head, NULL);
- cbs_tail = (struct cds_wfq_node **)
- uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
- synchronize_rcu();
- cbcount = 0;
- do {
- while (cbs->next == NULL &&
- &cbs->next != cbs_tail)
- poll(NULL, 0, 1);
- if (cbs == &crdp->cbs.dummy) {
- cbs = cbs->next;
- continue;
- }
- rhp = (struct rcu_head *)cbs;
- cbs = cbs->next;
- rhp->func(rhp);
- cbcount++;
- } while (cbs != NULL);
- uatomic_sub(&crdp->qlen, cbcount);
- }
- if (crdp->flags & URCU_CALL_RCU_STOP)
- break;
- if (crdp->flags & URCU_CALL_RCU_RT)
- poll(NULL, 0, 10);
- else {
- call_rcu_lock(&crdp->mtx);
- _CMM_STORE_SHARED(crdp->flags,
- crdp->flags & ~URCU_CALL_RCU_RUNNING);
- if (&crdp->cbs.head ==
- _CMM_LOAD_SHARED(crdp->cbs.tail) &&
- pthread_cond_wait(&crdp->cond, &crdp->mtx) != 0) {
- perror("pthread_cond_wait");
- exit(-1);
- }
- _CMM_STORE_SHARED(crdp->flags,
- crdp->flags | URCU_CALL_RCU_RUNNING);
- poll(NULL, 0, 10);
- call_rcu_unlock(&crdp->mtx);
- }
- }
- call_rcu_lock(&crdp->mtx);
- crdp->flags |= URCU_CALL_RCU_STOPPED;
- call_rcu_unlock(&crdp->mtx);
- return NULL;
-}
-
-/*
- * Create both a call_rcu thread and the corresponding call_rcu_data
- * structure, linking the structure in as specified. Caller must hold
- * call_rcu_mutex.
- */
-
-static void call_rcu_data_init(struct call_rcu_data **crdpp,
- unsigned long flags)
-{
- struct call_rcu_data *crdp;
-
- crdp = malloc(sizeof(*crdp));
- if (crdp == NULL) {
- fprintf(stderr, "Out of memory.\n");
- exit(-1);
- }
- memset(crdp, '\0', sizeof(*crdp));
- cds_wfq_init(&crdp->cbs);
- crdp->qlen = 0;
- if (pthread_mutex_init(&crdp->mtx, NULL) != 0) {
- perror("pthread_mutex_init");
- exit(-1);
- }
- if (pthread_cond_init(&crdp->cond, NULL) != 0) {
- perror("pthread_cond_init");
- exit(-1);
- }
- crdp->flags = flags | URCU_CALL_RCU_RUNNING;
- cds_list_add(&crdp->list, &call_rcu_data_list);
- cmm_smp_mb(); /* Structure initialized before pointer is planted. */
- *crdpp = crdp;
- if (pthread_create(&crdp->tid, NULL, call_rcu_thread, crdp) != 0) {
- perror("pthread_create");
- exit(-1);
- }
-}
-
-/*
- * Return a pointer to the call_rcu_data structure for the specified
- * CPU, returning NULL if there is none. We cannot automatically
- * created it because the platform we are running on might not define
- * sched_getcpu().
- */
-
-struct call_rcu_data *get_cpu_call_rcu_data(int cpu)
-{
- static int warned = 0;
-
- if (per_cpu_call_rcu_data == NULL)
- return NULL;
- if (!warned && maxcpus > 0 && (cpu < 0 || maxcpus <= cpu)) {
- fprintf(stderr, "[error] liburcu: get CPU # out of range\n");
- warned = 1;
- }
- if (cpu < 0 || maxcpus <= cpu)
- return NULL;
- return per_cpu_call_rcu_data[cpu];
-}
-
-/*
- * Return the tid corresponding to the call_rcu thread whose
- * call_rcu_data structure is specified.
- */
-
-pthread_t get_call_rcu_thread(struct call_rcu_data *crdp)
-{
- return crdp->tid;
-}
-
-/*
- * Create a call_rcu_data structure (with thread) and return a pointer.
- */
-
-static struct call_rcu_data *__create_call_rcu_data(unsigned long flags)
-{
- struct call_rcu_data *crdp;
-
- call_rcu_data_init(&crdp, flags);
- return crdp;
-}
-
-struct call_rcu_data *create_call_rcu_data(unsigned long flags)
-{
- struct call_rcu_data *crdp;
-
- call_rcu_lock(&call_rcu_mutex);
- crdp = __create_call_rcu_data(flags);
- call_rcu_unlock(&call_rcu_mutex);
- return crdp;
-}
-
-/*
- * Set the specified CPU to use the specified call_rcu_data structure.
- *
- * Use NULL to remove a CPU's call_rcu_data structure, but it is
- * the caller's responsibility to dispose of the removed structure.
- * Use get_cpu_call_rcu_data() to obtain a pointer to the old structure
- * (prior to NULLing it out, of course).
- */
-
-int set_cpu_call_rcu_data(int cpu, struct call_rcu_data *crdp)
-{
- int warned = 0;
-
- call_rcu_lock(&call_rcu_mutex);
- if (cpu < 0 || maxcpus <= cpu) {
- if (!warned) {
- fprintf(stderr, "[error] liburcu: set CPU # out of range\n");
- warned = 1;
- }
- call_rcu_unlock(&call_rcu_mutex);
- errno = EINVAL;
- return -EINVAL;
- }
- alloc_cpu_call_rcu_data();
- call_rcu_unlock(&call_rcu_mutex);
- if (per_cpu_call_rcu_data == NULL) {
- errno = ENOMEM;
- return -ENOMEM;
- }
- per_cpu_call_rcu_data[cpu] = crdp;
- return 0;
-}
-
-/*
- * Return a pointer to the default call_rcu_data structure, creating
- * one if need be. Because we never free call_rcu_data structures,
- * we don't need to be in an RCU read-side critical section.
- */
-
-struct call_rcu_data *get_default_call_rcu_data(void)
-{
- if (default_call_rcu_data != NULL)
- return rcu_dereference(default_call_rcu_data);
- call_rcu_lock(&call_rcu_mutex);
- if (default_call_rcu_data != NULL) {
- call_rcu_unlock(&call_rcu_mutex);
- return default_call_rcu_data;
- }
- call_rcu_data_init(&default_call_rcu_data, 0);
- call_rcu_unlock(&call_rcu_mutex);
- return default_call_rcu_data;
-}
-
-/*
- * Return the call_rcu_data structure that applies to the currently
- * running thread. Any call_rcu_data structure assigned specifically
- * to this thread has first priority, followed by any call_rcu_data
- * structure assigned to the CPU on which the thread is running,
- * followed by the default call_rcu_data structure. If there is not
- * yet a default call_rcu_data structure, one will be created.
- */
-struct call_rcu_data *get_call_rcu_data(void)
-{
- int curcpu;
- static int warned = 0;
-
- if (thread_call_rcu_data != NULL)
- return thread_call_rcu_data;
- if (maxcpus <= 0)
- return get_default_call_rcu_data();
- curcpu = sched_getcpu();
- if (!warned && (curcpu < 0 || maxcpus <= curcpu)) {
- fprintf(stderr, "[error] liburcu: gcrd CPU # out of range\n");
- warned = 1;
- }
- if (curcpu >= 0 && maxcpus > curcpu &&
- per_cpu_call_rcu_data != NULL &&
- per_cpu_call_rcu_data[curcpu] != NULL)
- return per_cpu_call_rcu_data[curcpu];
- return get_default_call_rcu_data();
-}
-
-/*
- * Return a pointer to this task's call_rcu_data if there is one.
- */
-
-struct call_rcu_data *get_thread_call_rcu_data(void)
-{
- return thread_call_rcu_data;
-}
-
-/*
- * Set this task's call_rcu_data structure as specified, regardless
- * of whether or not this task already had one. (This allows switching
- * to and from real-time call_rcu threads, for example.)
- *
- * Use NULL to remove a thread's call_rcu_data structure, but it is
- * the caller's responsibility to dispose of the removed structure.
- * Use get_thread_call_rcu_data() to obtain a pointer to the old structure
- * (prior to NULLing it out, of course).
- */
-
-void set_thread_call_rcu_data(struct call_rcu_data *crdp)
-{
- thread_call_rcu_data = crdp;
-}
-
-/*
- * Create a separate call_rcu thread for each CPU. This does not
- * replace a pre-existing call_rcu thread -- use the set_cpu_call_rcu_data()
- * function if you want that behavior.
- */
-
-int create_all_cpu_call_rcu_data(unsigned long flags)
-{
- int i;
- struct call_rcu_data *crdp;
- int ret;
-
- call_rcu_lock(&call_rcu_mutex);
- alloc_cpu_call_rcu_data();
- call_rcu_unlock(&call_rcu_mutex);
- if (maxcpus <= 0) {
- errno = EINVAL;
- return -EINVAL;
- }
- if (per_cpu_call_rcu_data == NULL) {
- errno = ENOMEM;
- return -ENOMEM;
- }
- for (i = 0; i < maxcpus; i++) {
- call_rcu_lock(&call_rcu_mutex);
- if (get_cpu_call_rcu_data(i)) {
- call_rcu_unlock(&call_rcu_mutex);
- continue;
- }
- crdp = __create_call_rcu_data(flags);
- if (crdp == NULL) {
- call_rcu_unlock(&call_rcu_mutex);
- errno = ENOMEM;
- return -ENOMEM;
- }
- call_rcu_unlock(&call_rcu_mutex);
- if ((ret = set_cpu_call_rcu_data(i, crdp)) != 0) {
- /* FIXME: Leaks crdp for now. */
- return ret; /* Can happen on race. */
- }
- }
- return 0;
-}
-
-/*
- * Wake up the call_rcu thread corresponding to the specified
- * call_rcu_data structure.
- */
-static void wake_call_rcu_thread(struct call_rcu_data *crdp)
-{
- if (!(_CMM_LOAD_SHARED(crdp->flags) & URCU_CALL_RCU_RT)) {
- call_rcu_lock(&crdp->mtx);
- if (!(_CMM_LOAD_SHARED(crdp->flags) & URCU_CALL_RCU_RUNNING)) {
- if (pthread_cond_signal(&crdp->cond) != 0) {
- perror("pthread_cond_signal");
- exit(-1);
- }
- }
- call_rcu_unlock(&crdp->mtx);
- }
-}
-
-/*
- * Schedule a function to be invoked after a following grace period.
- * This is the only function that must be called -- the others are
- * only present to allow applications to tune their use of RCU for
- * maximum performance.
- *
- * Note that unless a call_rcu thread has not already been created,
- * the first invocation of call_rcu() will create one. So, if you
- * need the first invocation of call_rcu() to be fast, make sure
- * to create a call_rcu thread first. One way to accomplish this is
- * "get_call_rcu_data();", and another is create_all_cpu_call_rcu_data().
- */
-
-void call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *head))
-{
- struct call_rcu_data *crdp;
-
- cds_wfq_node_init(&head->next);
- head->func = func;
- crdp = get_call_rcu_data();
- cds_wfq_enqueue(&crdp->cbs, &head->next);
- uatomic_inc(&crdp->qlen);
- wake_call_rcu_thread(crdp);
-}
-
-/*
- * Free up the specified call_rcu_data structure, terminating the
- * associated call_rcu thread. The caller must have previously
- * removed the call_rcu_data structure from per-thread or per-CPU
- * usage. For example, set_cpu_call_rcu_data(cpu, NULL) for per-CPU
- * call_rcu_data structures or set_thread_call_rcu_data(NULL) for
- * per-thread call_rcu_data structures.
- *
- * We silently refuse to free up the default call_rcu_data structure
- * because that is where we put any leftover callbacks. Note that
- * the possibility of self-spawning callbacks makes it impossible
- * to execute all the callbacks in finite time without putting any
- * newly spawned callbacks somewhere else. The "somewhere else" of
- * last resort is the default call_rcu_data structure.
- *
- * We also silently refuse to free NULL pointers. This simplifies
- * the calling code.
- */
-void call_rcu_data_free(struct call_rcu_data *crdp)
-{
- struct cds_wfq_node *cbs;
- struct cds_wfq_node **cbs_tail;
- struct cds_wfq_node **cbs_endprev;
-
- if (crdp == NULL || crdp == default_call_rcu_data) {
- return;
- }
- if ((crdp->flags & URCU_CALL_RCU_STOPPED) == 0) {
- call_rcu_lock(&crdp->mtx);
- crdp->flags |= URCU_CALL_RCU_STOP;
- call_rcu_unlock(&crdp->mtx);
- wake_call_rcu_thread(crdp);
- while ((crdp->flags & URCU_CALL_RCU_STOPPED) == 0)
- poll(NULL, 0, 1);
- }
- if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
- while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
- poll(NULL, 0, 1);
- _CMM_STORE_SHARED(crdp->cbs.head, NULL);
- cbs_tail = (struct cds_wfq_node **)
- uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
- cbs_endprev = (struct cds_wfq_node **)
- uatomic_xchg(&default_call_rcu_data, cbs_tail);
- *cbs_endprev = cbs;
- uatomic_add(&default_call_rcu_data->qlen,
- uatomic_read(&crdp->qlen));
- cds_list_del(&crdp->list);
- free(crdp);
- }
-}
-
-/*
- * Clean up all the per-CPU call_rcu threads.
- */
-void free_all_cpu_call_rcu_data(void)
-{
- int cpu;
- struct call_rcu_data *crdp;
-
- if (maxcpus <= 0)
- return;
- for (cpu = 0; cpu < maxcpus; cpu++) {
- crdp = get_cpu_call_rcu_data(cpu);
- if (crdp == NULL)
- continue;
- set_cpu_call_rcu_data(cpu, NULL);
- call_rcu_data_free(crdp);
- }
-}
-
-/*
- * Acquire the call_rcu_mutex in order to ensure that the child sees
- * all of the call_rcu() data structures in a consistent state.
- * Suitable for pthread_atfork() and friends.
- */
-void call_rcu_before_fork(void)
-{
- call_rcu_lock(&call_rcu_mutex);
-}
-
-/*
- * Clean up call_rcu data structures in the parent of a successful fork()
- * that is not followed by exec() in the child. Suitable for
- * pthread_atfork() and friends.
- */
-void call_rcu_after_fork_parent(void)
-{
- call_rcu_unlock(&call_rcu_mutex);
-}
-
-/*
- * Clean up call_rcu data structures in the child of a successful fork()
- * that is not followed by exec(). Suitable for pthread_atfork() and
- * friends.
- */
-void call_rcu_after_fork_child(void)
-{
- struct call_rcu_data *crdp;
-
- /* Release the mutex. */
- call_rcu_unlock(&call_rcu_mutex);
-
- /*
- * Allocate a new default call_rcu_data structure in order
- * to get a working call_rcu thread to go with it.
- */
- default_call_rcu_data = NULL;
- (void)get_default_call_rcu_data();
-
- /* Dispose of all of the rest of the call_rcu_data structures. */
- while (call_rcu_data_list.next != call_rcu_data_list.prev) {
- crdp = cds_list_entry(call_rcu_data_list.prev,
- struct call_rcu_data, list);
- if (crdp == default_call_rcu_data)
- crdp = cds_list_entry(crdp->list.prev,
- struct call_rcu_data, list);
- crdp->flags = URCU_CALL_RCU_STOPPED;
- call_rcu_data_free(crdp);
- }
-}
--- /dev/null
+#ifndef _URCU_MAP_H
+#define _URCU_MAP_H
+
+/*
+ * urcu-map.h
+ *
+ * Userspace RCU header -- name mapping to allow multiple flavors to be
+ * used in the same executable.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
+ *
+ * LGPL-compatible code should include this header with :
+ *
+ * #define _LGPL_SOURCE
+ * #include <urcu.h>
+ *
+ * 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.
+ */
+
+/* Mapping macros to allow multiple flavors in a single binary. */
+
+#ifdef RCU_MEMBARRIER
+
+#define rcu_read_lock rcu_read_lock_memb
+#define _rcu_read_lock _rcu_read_lock_memb
+#define rcu_read_unlock rcu_read_unlock_memb
+#define _rcu_read_unlock _rcu_read_unlock_memb
+#define rcu_register_thread rcu_register_thread_memb
+#define rcu_unregister_thread rcu_unregister_thread_memb
+#define rcu_init rcu_init_memb
+#define rcu_exit rcu_exit_memb
+#define synchronize_rcu synchronize_rcu_memb
+#define rcu_reader rcu_reader_memb
+#define rcu_gp_ctr rcu_gp_ctr_memb
+
+#define get_cpu_call_rcu_data get_cpu_call_rcu_data_memb
+#define get_call_rcu_thread get_call_rcu_thread_memb
+#define create_call_rcu_data create_call_rcu_data_memb
+#define set_cpu_call_rcu_data set_cpu_call_rcu_data_memb
+#define get_default_call_rcu_data get_default_call_rcu_data_memb
+#define get_call_rcu_data get_call_rcu_data_memb
+#define get_thread_call_rcu_data get_thread_call_rcu_data_memb
+#define set_thread_call_rcu_data set_thread_call_rcu_data_memb
+#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_memb
+#define free_all_cpu_call_rcu_data free_all_cpu_call_rcu_data_memb
+#define call_rcu call_rcu_memb
+
+#elif defined(RCU_SIGNAL)
+
+#define rcu_read_lock rcu_read_lock_sig
+#define _rcu_read_lock _rcu_read_lock_sig
+#define rcu_read_unlock rcu_read_unlock_sig
+#define _rcu_read_unlock _rcu_read_unlock_sig
+#define rcu_register_thread rcu_register_thread_sig
+#define rcu_unregister_thread rcu_unregister_thread_sig
+#define rcu_init rcu_init_sig
+#define rcu_exit rcu_exit_sig
+#define synchronize_rcu synchronize_rcu_sig
+#define rcu_reader rcu_reader_sig
+#define rcu_gp_ctr rcu_gp_ctr_sig
+
+#define get_cpu_call_rcu_data get_cpu_call_rcu_data_sig
+#define get_call_rcu_thread get_call_rcu_thread_sig
+#define create_call_rcu_data create_call_rcu_data_sig
+#define set_cpu_call_rcu_data set_cpu_call_rcu_data_sig
+#define get_default_call_rcu_data get_default_call_rcu_data_sig
+#define get_call_rcu_data get_call_rcu_data_sig
+#define get_thread_call_rcu_data get_thread_call_rcu_data_sig
+#define set_thread_call_rcu_data set_thread_call_rcu_data_sig
+#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_sig
+#define free_all_cpu_call_rcu_data free_all_cpu_call_rcu_data_sig
+#define call_rcu call_rcu_sig
+
+#elif defined(RCU_MB)
+
+#define rcu_read_lock rcu_read_lock_mb
+#define _rcu_read_lock _rcu_read_lock_mb
+#define rcu_read_unlock rcu_read_unlock_mb
+#define _rcu_read_unlock _rcu_read_unlock_mb
+#define rcu_register_thread rcu_register_thread_mb
+#define rcu_unregister_thread rcu_unregister_thread_mb
+#define rcu_init rcu_init_mb
+#define rcu_exit rcu_exit_mb
+#define synchronize_rcu synchronize_rcu_mb
+#define rcu_reader rcu_reader_mb
+#define rcu_gp_ctr rcu_gp_ctr_mb
+
+#define get_cpu_call_rcu_data get_cpu_call_rcu_data_mb
+#define get_call_rcu_thread get_call_rcu_thread_mb
+#define create_call_rcu_data create_call_rcu_data_mb
+#define set_cpu_call_rcu_data set_cpu_call_rcu_data_mb
+#define get_default_call_rcu_data get_default_call_rcu_data_mb
+#define get_call_rcu_data get_call_rcu_data_mb
+#define get_thread_call_rcu_data get_thread_call_rcu_data_mb
+#define set_thread_call_rcu_data set_thread_call_rcu_data_mb
+#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_mb
+#define free_all_cpu_call_rcu_data free_all_cpu_call_rcu_data_mb
+#define call_rcu call_rcu_mb
+
+#endif
+
+#endif /* _URCU_MAP_H */
--- /dev/null
+#ifndef _URCU_QSBR_MAP_H
+#define _URCU_QSBR_MAP_H
+
+/*
+ * urcu-map.h
+ *
+ * Userspace RCU header -- name mapping to allow multiple flavors to be
+ * used in the same executable.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
+ *
+ * LGPL-compatible code should include this header with :
+ *
+ * #define _LGPL_SOURCE
+ * #include <urcu.h>
+ *
+ * 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.
+ */
+
+/* Mapping macros to allow multiple flavors in a single binary. */
+
+#define rcu_read_lock rcu_read_lock_qsbr
+#define _rcu_read_lock _rcu_read_lock_qsbr
+#define rcu_read_unlock rcu_read_unlock_qsbr
+#define _rcu_read_unlock _rcu_read_unlock_qsbr
+#define rcu_quiescent_state rcu_quiescent_state_qsbr
+#define _rcu_quiescent_state _rcu_quiescent_state_qsbr
+#define rcu_thread_offline rcu_thread_offline_qsbr
+#define rcu_thread_online rcu_thread_online_qsbr
+#define rcu_register_thread rcu_register_thread_qsbr
+#define rcu_unregister_thread rcu_unregister_thread_qsbr
+#define rcu_exit rcu_exit_qsbr
+#define synchronize_rcu synchronize_rcu_qsbr
+#define rcu_reader rcu_reader_qsbr
+#define rcu_gp_ctr rcu_gp_ctr_qsbr
+
+#define get_cpu_call_rcu_data get_cpu_call_rcu_data_qsbr
+#define get_call_rcu_thread get_call_rcu_thread_qsbr
+#define create_call_rcu_data create_call_rcu_data_qsbr
+#define set_cpu_call_rcu_data set_cpu_call_rcu_data_qsbr
+#define get_default_call_rcu_data get_default_call_rcu_data_qsbr
+#define get_call_rcu_data get_call_rcu_data_qsbr
+#define get_thread_call_rcu_data get_thread_call_rcu_data_qsbr
+#define set_thread_call_rcu_data set_thread_call_rcu_data_qsbr
+#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_qsbr
+#define call_rcu call_rcu_qsbr
+
+#endif /* _URCU_QSBR_MAP_H */
#include <errno.h>
#include <poll.h>
+#include "urcu-qsbr-map.h"
+
#define BUILD_QSBR_LIB
#include "urcu-qsbr-static.h"
/* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
#endif /* !(CAA_BITS_PER_LONG < 64) */
/*
- * Must commit rcu_gp_ctr update to memory before waiting for quiescent
- * state. Failure to do so could result in the writer waiting forever
- * while new readers are always accessing data (no progress). Enforce
- * compiler-order of store to rcu_gp_ctr before load rcu_reader ctr.
+ * Must commit rcu_gp_ctr update to memory before waiting for
+ * quiescent state. Failure to do so could result in the writer
+ * waiting forever while new readers are always accessing data
+ * (no progress). Enforce compiler-order of store to rcu_gp_ctr
+ * before load rcu_reader ctr.
*/
cmm_barrier();
/*
* Mark the writer thread offline to make sure we don't wait for
- * our own quiescent state. This allows using synchronize_rcu() in
- * threads registered as readers.
+ * our own quiescent state. This allows using synchronize_rcu()
+ * in threads registered as readers.
*/
if (was_online)
CMM_STORE_SHARED(rcu_reader.ctr, 0);
/*
* Must finish waiting for quiescent state for parity 0 before
- * committing next rcu_gp_ctr update to memory. Failure to do so could
- * result in the writer waiting forever while new readers are always
- * accessing data (no progress). Enforce compiler-order of load
- * rcu_reader ctr before store to rcu_gp_ctr.
+ * committing next rcu_gp_ctr update to memory. Failure to
+ * do so could result in the writer waiting forever while new
+ * readers are always accessing data (no progress). Enforce
+ * compiler-order of load rcu_reader ctr before store to
+ * rcu_gp_ctr.
*/
cmm_barrier();
* freed.
*/
if (was_online)
- _CMM_STORE_SHARED(rcu_reader.ctr, CMM_LOAD_SHARED(rcu_gp_ctr));
+ _CMM_STORE_SHARED(rcu_reader.ctr,
+ CMM_LOAD_SHARED(rcu_gp_ctr));
cmm_smp_mb();
}
#else /* !(CAA_BITS_PER_LONG < 64) */
/*
* Mark the writer thread offline to make sure we don't wait for
- * our own quiescent state. This allows using synchronize_rcu() in
- * threads registered as readers.
+ * our own quiescent state. This allows using synchronize_rcu()
+ * in threads registered as readers.
*/
cmm_smp_mb();
if (was_online)
mutex_unlock(&rcu_gp_lock);
if (was_online)
- _CMM_STORE_SHARED(rcu_reader.ctr, CMM_LOAD_SHARED(rcu_gp_ctr));
+ _CMM_STORE_SHARED(rcu_reader.ctr,
+ CMM_LOAD_SHARED(rcu_gp_ctr));
cmm_smp_mb();
}
#endif /* !(CAA_BITS_PER_LONG < 64) */
{
assert(cds_list_empty(®istry));
}
+
+#include "urcu-call-rcu-impl.h"
extern "C" {
#endif
+#include "urcu-qsbr-map.h"
+
/*
* Important !
*
* rcu_read_unlock()
*
* Mark the beginning and end of a read-side critical section.
- * DON'T FORGET TO USE rcu_register_thread/rcu_unregister_thread() FOR EACH
- * THREAD WITH READ-SIDE CRITICAL SECTION.
+ * DON'T FORGET TO USE rcu_register_thread/rcu_unregister_thread()
+ * FOR EACH THREAD WITH READ-SIDE CRITICAL SECTION.
*/
-#define rcu_read_lock() _rcu_read_lock()
-#define rcu_read_unlock() _rcu_read_unlock()
+#define rcu_read_lock_qsbr() _rcu_read_lock()
+#define rcu_read_unlock_qsbr() _rcu_read_unlock()
-#define rcu_quiescent_state() _rcu_quiescent_state()
-#define rcu_thread_offline() _rcu_thread_offline()
-#define rcu_thread_online() _rcu_thread_online()
+#define rcu_quiescent_state_qsbr() _rcu_quiescent_state()
+#define rcu_thread_offline_qsbr() _rcu_thread_offline()
+#define rcu_thread_online_qsbr() _rcu_thread_online()
#else /* !_LGPL_SOURCE */
}
#endif
+#include "urcu-call-rcu.h"
+
#endif /* _URCU_QSBR_H */
#include <errno.h>
#include <poll.h>
+#include "urcu-map.h"
+
#include "urcu-static.h"
/* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
#include "urcu.h"
assert(act.sa_sigaction == sigrcu_handler);
assert(cds_list_empty(®istry));
}
+
#endif /* #ifdef RCU_SIGNAL */
+
+#include "urcu-call-rcu-impl.h"
extern "C" {
#endif
+#include "urcu-map.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.
+ * with rcu_register_thread_mb() before calling rcu_read_lock_mb().
+ * rcu_unregister_thread_mb() should be called before the thread exits.
*/
#ifdef _LGPL_SOURCE
* DON'T FORGET TO USE RCU_REGISTER/UNREGISTER_THREAD() FOR EACH THREAD WITH
* READ-SIDE CRITICAL SECTION.
*/
-#define rcu_read_lock() _rcu_read_lock()
-#define rcu_read_unlock() _rcu_read_unlock()
+#ifdef RCU_MEMBARRIER
+#define rcu_read_lock_memb() _rcu_read_lock()
+#define rcu_read_unlock_memb() _rcu_read_unlock()
+#elif defined(RCU_SIGNAL)
+#define rcu_read_lock_sig() _rcu_read_lock()
+#define rcu_read_unlock_sig() _rcu_read_unlock()
+#elif defined(RCU_MB)
+#define rcu_read_lock_mb() _rcu_read_lock()
+#define rcu_read_unlock_mb() _rcu_read_unlock()
+#endif
#else /* !_LGPL_SOURCE */
}
#endif
+#include "urcu-call-rcu.h"
+
#endif /* _URCU_H */
projects / urcu.git / commitdiff
