mutex: fixup fio_mutex_down_timeout()

[fio.git] / mutex.c

diff --git a/mutex.c b/mutex.c
index e1fbb607f1a416fb06a25a611f0f4233c9814357..a48e37d0f11a947efbdcb6a278c59b82b58b3372 100644 (file)
--- a/mutex.c
+++ b/mutex.c
@@ -15,39 +15,34 @@
 #include "arch/arch.h"
 #include "os/os.h"
 #include "helpers.h"
-#include "time.h"
+#include "fio_time.h"
 #include "gettime.h"
 
-void fio_mutex_remove(struct fio_mutex *mutex)
+void __fio_mutex_remove(struct fio_mutex *mutex)
 {
        assert(mutex->magic == FIO_MUTEX_MAGIC);
        pthread_cond_destroy(&mutex->cond);
+}
+
+void fio_mutex_remove(struct fio_mutex *mutex)
+{
+       __fio_mutex_remove(mutex);
        munmap((void *) mutex, sizeof(*mutex));
 }
 
-struct fio_mutex *fio_mutex_init(int value)
+int __fio_mutex_init(struct fio_mutex *mutex, int value)
 {
-       struct fio_mutex *mutex = NULL;
        pthread_mutexattr_t attr;
        pthread_condattr_t cond;
        int ret;
 
-       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;
-       }
-
        mutex->value = value;
        mutex->magic = FIO_MUTEX_MAGIC;
 
        ret = pthread_mutexattr_init(&attr);
        if (ret) {
                log_err("pthread_mutexattr_init: %s\n", strerror(ret));
-               goto err;
+               return ret;
        }
 
        /*
@@ -57,7 +52,7 @@ struct fio_mutex *fio_mutex_init(int value)
        ret = pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED);
        if (ret) {
                log_err("pthread_mutexattr_setpshared: %s\n", strerror(ret));
-               goto err;
+               return ret;
        }
 #endif
 
@@ -70,26 +65,42 @@ struct fio_mutex *fio_mutex_init(int value)
        ret = pthread_mutex_init(&mutex->lock, &attr);
        if (ret) {
                log_err("pthread_mutex_init: %s\n", strerror(ret));
-               goto err;
+               return ret;
        }
 
        pthread_condattr_destroy(&cond);
        pthread_mutexattr_destroy(&attr);
+       return 0;
+}
 
-       return mutex;
-err:
-       if (mutex)
-               fio_mutex_remove(mutex);
+struct fio_mutex *fio_mutex_init(int value)
+{
+       struct fio_mutex *mutex = 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");
+               return NULL;
+       }
+
+       if (!__fio_mutex_init(mutex, value))
+               return mutex;
+
+       fio_mutex_remove(mutex);
        return NULL;
 }
 
-static int mutex_timed_out(struct timeval *t, unsigned int seconds)
+static bool mutex_timed_out(struct timeval *t, unsigned int msecs)
 {
-       return mtime_since_now(t) >= seconds * 1000;
+       struct timeval now;
+
+       gettimeofday(&now, NULL);
+       return mtime_since(t, &now) >= msecs;
 }
 
-int fio_mutex_down_timeout(struct fio_mutex *mutex, unsigned int seconds)
+int fio_mutex_down_timeout(struct fio_mutex *mutex, unsigned int msecs)
 {
        struct timeval tv_s;
        struct timespec t;
@@ -98,30 +109,52 @@ int fio_mutex_down_timeout(struct fio_mutex *mutex, unsigned int seconds)
        assert(mutex->magic == FIO_MUTEX_MAGIC);
 
        gettimeofday(&tv_s, NULL);
-       t.tv_sec = tv_s.tv_sec + seconds;
+       t.tv_sec = tv_s.tv_sec;
        t.tv_nsec = tv_s.tv_usec * 1000;
 
+       t.tv_sec += msecs / 1000;
+       t.tv_nsec += ((msecs * 1000000) % 1000000000);
+       if (t.tv_nsec >= 1000000000) {
+               t.tv_nsec -= 1000000000;
+               t.tv_sec++;
+       }
+
        pthread_mutex_lock(&mutex->lock);
 
+       mutex->waiters++;
        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))
+               if (ret == ETIMEDOUT && !mutex_timed_out(&tv_s, msecs))
                        ret = 0;
-
-               mutex->waiters--;
        }
+       mutex->waiters--;
 
        if (!ret) {
                mutex->value--;
                pthread_mutex_unlock(&mutex->lock);
        }
 
+       pthread_mutex_unlock(&mutex->lock);
+       return ret;
+}
+
+bool fio_mutex_down_trylock(struct fio_mutex *mutex)
+{
+       bool ret = true;
+
+       assert(mutex->magic == FIO_MUTEX_MAGIC);
+
+       pthread_mutex_lock(&mutex->lock);
+       if (mutex->value) {
+               mutex->value--;
+               ret = false;
+       }
+       pthread_mutex_unlock(&mutex->lock);
+
        return ret;
 }
 
@@ -143,14 +176,19 @@ void fio_mutex_down(struct fio_mutex *mutex)
 
 void fio_mutex_up(struct fio_mutex *mutex)
 {
+       int do_wake = 0;
+
        assert(mutex->magic == FIO_MUTEX_MAGIC);
 
        pthread_mutex_lock(&mutex->lock);
        read_barrier();
        if (!mutex->value && mutex->waiters)
-               pthread_cond_signal(&mutex->cond);
+               do_wake = 1;
        mutex->value++;
        pthread_mutex_unlock(&mutex->lock);
+
+       if (do_wake)
+               pthread_cond_signal(&mutex->cond);
 }
 
 void fio_rwlock_write(struct fio_rwlock *lock)