#include <config.h>
#include "ovs-thread.h"
#include <errno.h>
+#include <poll.h>
+#include <stdlib.h>
+#include <unistd.h>
#include "compiler.h"
+#include "poll-loop.h"
+#include "socket-util.h"
#include "util.h"
#ifdef __CHECKER__
* cut-and-paste. Since "sparse" is just a checker, not a compiler, it
* doesn't matter that we don't define them. */
#else
+#include "vlog.h"
+
+VLOG_DEFINE_THIS_MODULE(ovs_thread);
+
+/* If there is a reason that we cannot fork anymore (unless the fork will be
+ * immediately followed by an exec), then this points to a string that
+ * explains why. */
+static const char *must_not_fork;
+
+/* True if we created any threads beyond the main initial thread. */
+static bool multithreaded;
+
+#define LOCK_FUNCTION(TYPE, FUN) \
+ void \
+ ovs_##TYPE##_##FUN##_at(const struct ovs_##TYPE *l_, \
+ const char *where) \
+ { \
+ struct ovs_##TYPE *l = CONST_CAST(struct ovs_##TYPE *, l_); \
+ int error = pthread_##TYPE##_##FUN(&l->lock); \
+ if (OVS_UNLIKELY(error)) { \
+ ovs_abort(error, "pthread_%s_%s failed", #TYPE, #FUN); \
+ } \
+ l->where = where; \
+ }
+LOCK_FUNCTION(mutex, lock);
+LOCK_FUNCTION(rwlock, rdlock);
+LOCK_FUNCTION(rwlock, wrlock);
+
+#define TRY_LOCK_FUNCTION(TYPE, FUN) \
+ int \
+ ovs_##TYPE##_##FUN##_at(const struct ovs_##TYPE *l_, \
+ const char *where) \
+ { \
+ struct ovs_##TYPE *l = CONST_CAST(struct ovs_##TYPE *, l_); \
+ int error = pthread_##TYPE##_##FUN(&l->lock); \
+ if (OVS_UNLIKELY(error) && error != EBUSY) { \
+ ovs_abort(error, "pthread_%s_%s failed", #TYPE, #FUN); \
+ } \
+ if (!error) { \
+ l->where = where; \
+ } \
+ return error; \
+ }
+TRY_LOCK_FUNCTION(mutex, trylock);
+TRY_LOCK_FUNCTION(rwlock, tryrdlock);
+TRY_LOCK_FUNCTION(rwlock, trywrlock);
+
+#define UNLOCK_FUNCTION(TYPE, FUN) \
+ void \
+ ovs_##TYPE##_##FUN(const struct ovs_##TYPE *l_) \
+ { \
+ struct ovs_##TYPE *l = CONST_CAST(struct ovs_##TYPE *, l_); \
+ int error; \
+ l->where = NULL; \
+ error = pthread_##TYPE##_##FUN(&l->lock); \
+ if (OVS_UNLIKELY(error)) { \
+ ovs_abort(error, "pthread_%s_%sfailed", #TYPE, #FUN); \
+ } \
+ }
+UNLOCK_FUNCTION(mutex, unlock);
+UNLOCK_FUNCTION(mutex, destroy);
+UNLOCK_FUNCTION(rwlock, unlock);
+UNLOCK_FUNCTION(rwlock, destroy);
+
#define XPTHREAD_FUNC1(FUNCTION, PARAM1) \
void \
x##FUNCTION(PARAM1 arg1) \
ovs_abort(error, "%s failed", #FUNCTION); \
} \
}
-#define XPTHREAD_TRY_FUNC1(FUNCTION, PARAM1) \
- int \
- x##FUNCTION(PARAM1 arg1) \
- { \
- int error = FUNCTION(arg1); \
- if (OVS_UNLIKELY(error && error != EBUSY)) { \
- ovs_abort(error, "%s failed", #FUNCTION); \
- } \
- return error; \
- }
#define XPTHREAD_FUNC2(FUNCTION, PARAM1, PARAM2) \
void \
x##FUNCTION(PARAM1 arg1, PARAM2 arg2) \
} \
}
-XPTHREAD_FUNC2(pthread_mutex_init, pthread_mutex_t *, pthread_mutexattr_t *);
-XPTHREAD_FUNC1(pthread_mutex_lock, pthread_mutex_t *);
-XPTHREAD_FUNC1(pthread_mutex_unlock, pthread_mutex_t *);
-XPTHREAD_TRY_FUNC1(pthread_mutex_trylock, pthread_mutex_t *);
-
-XPTHREAD_FUNC2(pthread_rwlock_init,
- pthread_rwlock_t *, pthread_rwlockattr_t *);
-XPTHREAD_FUNC1(pthread_rwlock_rdlock, pthread_rwlock_t *);
-XPTHREAD_FUNC1(pthread_rwlock_wrlock, pthread_rwlock_t *);
-XPTHREAD_FUNC1(pthread_rwlock_unlock, pthread_rwlock_t *);
-XPTHREAD_TRY_FUNC1(pthread_rwlock_tryrdlock, pthread_rwlock_t *);
-XPTHREAD_TRY_FUNC1(pthread_rwlock_trywrlock, pthread_rwlock_t *);
+XPTHREAD_FUNC1(pthread_mutexattr_init, pthread_mutexattr_t *);
+XPTHREAD_FUNC1(pthread_mutexattr_destroy, pthread_mutexattr_t *);
+XPTHREAD_FUNC2(pthread_mutexattr_settype, pthread_mutexattr_t *, int);
+XPTHREAD_FUNC2(pthread_mutexattr_gettype, pthread_mutexattr_t *, int *);
XPTHREAD_FUNC2(pthread_cond_init, pthread_cond_t *, pthread_condattr_t *);
+XPTHREAD_FUNC1(pthread_cond_destroy, pthread_cond_t *);
XPTHREAD_FUNC1(pthread_cond_signal, pthread_cond_t *);
XPTHREAD_FUNC1(pthread_cond_broadcast, pthread_cond_t *);
-XPTHREAD_FUNC2(pthread_cond_wait, pthread_cond_t *, pthread_mutex_t *);
typedef void destructor_func(void *);
XPTHREAD_FUNC2(pthread_key_create, pthread_key_t *, destructor_func *);
+void
+ovs_mutex_init(const struct ovs_mutex *l_, int type)
+{
+ struct ovs_mutex *l = CONST_CAST(struct ovs_mutex *, l_);
+ pthread_mutexattr_t attr;
+ int error;
+
+ l->where = NULL;
+ xpthread_mutexattr_init(&attr);
+ xpthread_mutexattr_settype(&attr, type);
+ error = pthread_mutex_init(&l->lock, &attr);
+ if (OVS_UNLIKELY(error)) {
+ ovs_abort(error, "pthread_mutex_init failed");
+ }
+ xpthread_mutexattr_destroy(&attr);
+}
+
+void
+ovs_rwlock_init(const struct ovs_rwlock *l_)
+{
+ struct ovs_rwlock *l = CONST_CAST(struct ovs_rwlock *, l_);
+ int error;
+
+ l->where = NULL;
+ error = pthread_rwlock_init(&l->lock, NULL);
+ if (OVS_UNLIKELY(error)) {
+ ovs_abort(error, "pthread_rwlock_init failed");
+ }
+}
+
+void
+ovs_mutex_cond_wait(pthread_cond_t *cond, const struct ovs_mutex *mutex_)
+{
+ struct ovs_mutex *mutex = CONST_CAST(struct ovs_mutex *, mutex_);
+ int error = pthread_cond_wait(cond, &mutex->lock);
+ if (OVS_UNLIKELY(error)) {
+ ovs_abort(error, "pthread_cond_wait failed");
+ }
+}
+
void
xpthread_create(pthread_t *threadp, pthread_attr_t *attr,
void *(*start)(void *), void *arg)
pthread_t thread;
int error;
+ forbid_forking("multiple threads exist");
+ multithreaded = true;
+
error = pthread_create(threadp ? threadp : &thread, attr, start, arg);
if (error) {
ovs_abort(error, "pthread_create failed");
bool
ovsthread_once_start__(struct ovsthread_once *once)
{
- xpthread_mutex_lock(&once->mutex);
+ ovs_mutex_lock(&once->mutex);
if (!ovsthread_once_is_done__(once)) {
return false;
}
- xpthread_mutex_unlock(&once->mutex);
+ ovs_mutex_unlock(&once->mutex);
return true;
}
-void OVS_RELEASES(once)
+void
ovsthread_once_done(struct ovsthread_once *once)
{
atomic_store(&once->done, true);
- xpthread_mutex_unlock(&once->mutex);
+ ovs_mutex_unlock(&once->mutex);
+}
+\f
+/* Asserts that the process has not yet created any threads (beyond the initial
+ * thread).
+ *
+ * ('where' is used in logging. Commonly one would use
+ * assert_single_threaded() to automatically provide the caller's source file
+ * and line number for 'where'.) */
+void
+assert_single_threaded_at(const char *where)
+{
+ if (multithreaded) {
+ VLOG_FATAL("%s: attempted operation not allowed when multithreaded",
+ where);
+ }
+}
+
+/* Forks the current process (checking that this is allowed). Aborts with
+ * VLOG_FATAL if fork() returns an error, and otherwise returns the value
+ * returned by fork().
+ *
+ * ('where' is used in logging. Commonly one would use xfork() to
+ * automatically provide the caller's source file and line number for
+ * 'where'.) */
+pid_t
+xfork_at(const char *where)
+{
+ pid_t pid;
+
+ if (must_not_fork) {
+ VLOG_FATAL("%s: attempted to fork but forking not allowed (%s)",
+ where, must_not_fork);
+ }
+
+ pid = fork();
+ if (pid < 0) {
+ VLOG_FATAL("%s: fork failed (%s)", where, ovs_strerror(errno));
+ }
+ return pid;
+}
+
+/* Notes that the process must not call fork() from now on, for the specified
+ * 'reason'. (The process may still fork() if it execs itself immediately
+ * afterward.) */
+void
+forbid_forking(const char *reason)
+{
+ ovs_assert(reason != NULL);
+ must_not_fork = reason;
+}
+
+/* Returns true if the process is allowed to fork, false otherwise. */
+bool
+may_fork(void)
+{
+ return !must_not_fork;
}
#endif
git://git.onelab.eu / sliver-openvswitch.git / blobdiff