X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=mutex.c;h=3b94beffc7342ae2f13879126e2da3433cb5bbf1;hp=17e62c9f5152c0ab29966915b8874a4a1592ce45;hb=355934b7ed82d13a5bfc043e2243013fd1e4e5bd;hpb=108fcc1142ad5d087978190dbd7dd782e9b17d1d

diff --git a/mutex.c b/mutex.c
index 17e62c9f..3b94beff 100644
--- a/mutex.c
+++ b/mutex.c
@@ -3,90 +3,193 @@
 #include <unistd.h>
 #include <stdlib.h>
 #include <fcntl.h>
+#include <time.h>
+#include <errno.h>
 #include <pthread.h>
 #include <sys/mman.h>
 
+#include "fio.h"
+#include "log.h"
 #include "mutex.h"
+#include "arch/arch.h"
+#include "os/os.h"
+#include "helpers.h"
+#include "time.h"
+#include "gettime.h"
 
-void fio_sem_remove(struct fio_sem *sem)
+void fio_mutex_remove(struct fio_mutex *mutex)
 {
-	close(sem->sem_fd);
-	munmap(sem, sizeof(*sem));
+	pthread_cond_destroy(&mutex->cond);
+	munmap((void *) mutex, sizeof(*mutex));
 }
 
-struct fio_sem *fio_sem_init(int value)
+struct fio_mutex *fio_mutex_init(int value)
 {
-	char sem_name[] = "/tmp/.fio_sem.XXXXXX";
-	struct fio_sem *sem = NULL;
+	struct fio_mutex *mutex = NULL;
 	pthread_mutexattr_t attr;
 	pthread_condattr_t cond;
-	int fd;
+	int ret;
 
-	fd = mkstemp(sem_name);
-	if (fd < 0) {
-		perror("open sem");
-		return NULL;
-	}
-
-	if (ftruncate(fd, sizeof(struct fio_sem)) < 0) {
-		perror("ftruncate sem");
-		goto err;
-	}
-
-	sem = mmap(NULL, sizeof(struct fio_sem), PROT_READ | PROT_WRITE,
-			MAP_SHARED, fd, 0);
-	if (sem == MAP_FAILED) {
-		perror("mmap sem");
-		close(fd);
-		sem = NULL;
+	mutex = (void *) mmap(NULL, sizeof(struct fio_mutex),
+				PROT_READ | PROT_WRITE,
+				OS_MAP_ANON | MAP_SHARED, -1, 0);
+	if (mutex == MAP_FAILED) {
+		perror("mmap mutex");
+		mutex = NULL;
 		goto err;
 	}
 
-	unlink(sem_name);
-	sem->sem_fd = fd;
-	sem->value = value;
+	mutex->value = value;
 
-	if (pthread_mutexattr_init(&attr)) {
-		perror("pthread_mutexattr_init");
+	ret = pthread_mutexattr_init(&attr);
+	if (ret) {
+		log_err("pthread_mutexattr_init: %s\n", strerror(ret));
 		goto err;
 	}
-	if (pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED)) {
-		perror("pthread_mutexattr_setpshared");
+
+	/*
+	 * Not all platforms support process shared mutexes (FreeBSD)
+	 */
+#ifdef FIO_HAVE_PSHARED_MUTEX
+	ret = pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED);
+	if (ret) {
+		log_err("pthread_mutexattr_setpshared: %s\n", strerror(ret));
 		goto err;
 	}
+#endif
 
 	pthread_condattr_init(&cond);
+#ifdef FIO_HAVE_PSHARED_MUTEX
 	pthread_condattr_setpshared(&cond, PTHREAD_PROCESS_SHARED);
-	pthread_cond_init(&sem->cond, &cond);
+#endif
+	pthread_cond_init(&mutex->cond, &cond);
 
-	if (pthread_mutex_init(&sem->lock, &attr)) {
-		perror("pthread_mutex_init");
+	ret = pthread_mutex_init(&mutex->lock, &attr);
+	if (ret) {
+		log_err("pthread_mutex_init: %s\n", strerror(ret));
 		goto err;
 	}
 
-	return sem;
+	pthread_condattr_destroy(&cond);
+	pthread_mutexattr_destroy(&attr);
+
+	return mutex;
 err:
-	if (sem)
-		fio_sem_remove(sem);
+	if (mutex)
+		fio_mutex_remove(mutex);
 
-	unlink(sem_name);
 	return NULL;
 }
 
-void fio_sem_down(struct fio_sem *sem)
+static int mutex_timed_out(struct timeval *t, unsigned int seconds)
+{
+	return mtime_since_now(t) >= seconds * 1000;
+}
+
+int fio_mutex_down_timeout(struct fio_mutex *mutex, unsigned int seconds)
+{
+	struct timeval tv_s;
+	struct timespec t;
+	int ret = 0;
+
+	gettimeofday(&tv_s, NULL);
+	t.tv_sec = tv_s.tv_sec + seconds;
+	t.tv_nsec = tv_s.tv_usec * 1000;
+
+	pthread_mutex_lock(&mutex->lock);
+
+	while (!mutex->value && !ret) {
+		mutex->waiters++;
+
+		/*
+		 * Some platforms (FreeBSD 9?) seems to return timed out
+		 * way too early, double check.
+		 */
+		ret = pthread_cond_timedwait(&mutex->cond, &mutex->lock, &t);
+		if (ret == ETIMEDOUT && !mutex_timed_out(&tv_s, seconds)) {
+			pthread_mutex_lock(&mutex->lock);
+			ret = 0;
+		}
+
+		mutex->waiters--;
+	}
+
+	if (!ret) {
+		mutex->value--;
+		pthread_mutex_unlock(&mutex->lock);
+	}
+
+	return ret;
+}
+
+void fio_mutex_down(struct fio_mutex *mutex)
+{
+	pthread_mutex_lock(&mutex->lock);
+
+	while (!mutex->value) {
+		mutex->waiters++;
+		pthread_cond_wait(&mutex->cond, &mutex->lock);
+		mutex->waiters--;
+	}
+
+	mutex->value--;
+	pthread_mutex_unlock(&mutex->lock);
+}
+
+void fio_mutex_up(struct fio_mutex *mutex)
+{
+	pthread_mutex_lock(&mutex->lock);
+	read_barrier();
+	if (!mutex->value && mutex->waiters)
+		pthread_cond_signal(&mutex->cond);
+	mutex->value++;
+	pthread_mutex_unlock(&mutex->lock);
+}
+
+void fio_mutex_down_write(struct fio_mutex *mutex)
+{
+	pthread_mutex_lock(&mutex->lock);
+
+	while (mutex->value != 0) {
+		mutex->waiters++;
+		pthread_cond_wait(&mutex->cond, &mutex->lock);
+		mutex->waiters--;
+	}
+
+	mutex->value--;
+	pthread_mutex_unlock(&mutex->lock);
+}
+
+void fio_mutex_down_read(struct fio_mutex *mutex)
+{
+	pthread_mutex_lock(&mutex->lock);
+
+	while (mutex->value < 0) {
+		mutex->waiters++;
+		pthread_cond_wait(&mutex->cond, &mutex->lock);
+		mutex->waiters--;
+	}
+
+	mutex->value++;
+	pthread_mutex_unlock(&mutex->lock);
+}
+
+void fio_mutex_up_read(struct fio_mutex *mutex)
 {
-	pthread_mutex_lock(&sem->lock);
-	while (sem->value == 0)
-		pthread_cond_wait(&sem->cond, &sem->lock);
-	sem->value--;
-	pthread_mutex_unlock(&sem->lock);
+	pthread_mutex_lock(&mutex->lock);
+	mutex->value--;
+	read_barrier();
+	if (mutex->value >= 0 && mutex->waiters)
+		pthread_cond_signal(&mutex->cond);
+	pthread_mutex_unlock(&mutex->lock);
 }
 
-void fio_sem_up(struct fio_sem *sem)
+void fio_mutex_up_write(struct fio_mutex *mutex)
 {
-	pthread_mutex_lock(&sem->lock);
-	if (!sem->value)
-		pthread_cond_signal(&sem->cond);
-	sem->value++;
-	pthread_mutex_unlock(&sem->lock);
+	pthread_mutex_lock(&mutex->lock);
+	mutex->value++;
+	read_barrier();
+	if (mutex->value >= 0 && mutex->waiters)
+		pthread_cond_signal(&mutex->cond);
+	pthread_mutex_unlock(&mutex->lock);
 }