| 1 | #include <stdio.h> |
| 2 | #include <string.h> |
| 3 | #include <unistd.h> |
| 4 | #include <stdlib.h> |
| 5 | #include <fcntl.h> |
| 6 | #include <time.h> |
| 7 | #include <pthread.h> |
| 8 | #include <sys/mman.h> |
| 9 | |
| 10 | #include "log.h" |
| 11 | #include "mutex.h" |
| 12 | #include "arch/arch.h" |
| 13 | #include "os/os.h" |
| 14 | |
| 15 | void fio_mutex_remove(struct fio_mutex *mutex) |
| 16 | { |
| 17 | close(mutex->mutex_fd); |
| 18 | munmap((void *) mutex, sizeof(*mutex)); |
| 19 | } |
| 20 | |
| 21 | struct fio_mutex *fio_mutex_init(int value) |
| 22 | { |
| 23 | char mutex_name[] = "/tmp/.fio_mutex.XXXXXX"; |
| 24 | struct fio_mutex *mutex = NULL; |
| 25 | pthread_mutexattr_t attr; |
| 26 | pthread_condattr_t cond; |
| 27 | int fd, ret, mflag; |
| 28 | |
| 29 | fd = mkstemp(mutex_name); |
| 30 | if (fd < 0) { |
| 31 | perror("open mutex"); |
| 32 | return NULL; |
| 33 | } |
| 34 | |
| 35 | if (ftruncate(fd, sizeof(struct fio_mutex)) < 0) { |
| 36 | perror("ftruncate mutex"); |
| 37 | goto err; |
| 38 | } |
| 39 | |
| 40 | mutex = (void *) mmap(NULL, sizeof(struct fio_mutex), |
| 41 | PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); |
| 42 | if (mutex == MAP_FAILED) { |
| 43 | perror("mmap mutex"); |
| 44 | close(fd); |
| 45 | mutex = NULL; |
| 46 | goto err; |
| 47 | } |
| 48 | |
| 49 | unlink(mutex_name); |
| 50 | mutex->mutex_fd = fd; |
| 51 | mutex->value = value; |
| 52 | |
| 53 | /* |
| 54 | * Not all platforms support process shared mutexes (FreeBSD) |
| 55 | */ |
| 56 | #ifdef FIO_HAVE_PSHARED_MUTEX |
| 57 | mflag = PTHREAD_PROCESS_SHARED; |
| 58 | #else |
| 59 | mflag = PTHREAD_PROCESS_PRIVATE; |
| 60 | #endif |
| 61 | |
| 62 | ret = pthread_mutexattr_init(&attr); |
| 63 | if (ret) { |
| 64 | log_err("pthread_mutexattr_init: %s\n", strerror(ret)); |
| 65 | goto err; |
| 66 | } |
| 67 | ret = pthread_mutexattr_setpshared(&attr, mflag); |
| 68 | if (ret) { |
| 69 | log_err("pthread_mutexattr_setpshared: %s\n", strerror(ret)); |
| 70 | goto err; |
| 71 | } |
| 72 | |
| 73 | pthread_condattr_init(&cond); |
| 74 | pthread_condattr_setpshared(&cond, mflag); |
| 75 | pthread_cond_init(&mutex->cond, &cond); |
| 76 | |
| 77 | ret = pthread_mutex_init(&mutex->lock, &attr); |
| 78 | if (ret) { |
| 79 | log_err("pthread_mutex_init: %s\n", strerror(ret)); |
| 80 | goto err; |
| 81 | } |
| 82 | |
| 83 | return mutex; |
| 84 | err: |
| 85 | if (mutex) |
| 86 | fio_mutex_remove(mutex); |
| 87 | |
| 88 | unlink(mutex_name); |
| 89 | return NULL; |
| 90 | } |
| 91 | |
| 92 | int fio_mutex_down_timeout(struct fio_mutex *mutex, unsigned int seconds) |
| 93 | { |
| 94 | struct timespec t; |
| 95 | int ret = 0; |
| 96 | |
| 97 | clock_gettime(CLOCK_REALTIME, &t); |
| 98 | t.tv_sec += seconds; |
| 99 | |
| 100 | pthread_mutex_lock(&mutex->lock); |
| 101 | |
| 102 | while (!mutex->value && !ret) { |
| 103 | mutex->waiters++; |
| 104 | ret = pthread_cond_timedwait(&mutex->cond, &mutex->lock, &t); |
| 105 | mutex->waiters--; |
| 106 | } |
| 107 | |
| 108 | if (!ret) { |
| 109 | mutex->value--; |
| 110 | pthread_mutex_unlock(&mutex->lock); |
| 111 | } |
| 112 | |
| 113 | return ret; |
| 114 | } |
| 115 | |
| 116 | void fio_mutex_down(struct fio_mutex *mutex) |
| 117 | { |
| 118 | pthread_mutex_lock(&mutex->lock); |
| 119 | |
| 120 | while (!mutex->value) { |
| 121 | mutex->waiters++; |
| 122 | pthread_cond_wait(&mutex->cond, &mutex->lock); |
| 123 | mutex->waiters--; |
| 124 | } |
| 125 | |
| 126 | mutex->value--; |
| 127 | pthread_mutex_unlock(&mutex->lock); |
| 128 | } |
| 129 | |
| 130 | void fio_mutex_up(struct fio_mutex *mutex) |
| 131 | { |
| 132 | pthread_mutex_lock(&mutex->lock); |
| 133 | read_barrier(); |
| 134 | if (!mutex->value && mutex->waiters) |
| 135 | pthread_cond_signal(&mutex->cond); |
| 136 | mutex->value++; |
| 137 | pthread_mutex_unlock(&mutex->lock); |
| 138 | } |
| 139 | |
| 140 | void fio_mutex_down_write(struct fio_mutex *mutex) |
| 141 | { |
| 142 | pthread_mutex_lock(&mutex->lock); |
| 143 | |
| 144 | while (mutex->value != 0) { |
| 145 | mutex->waiters++; |
| 146 | pthread_cond_wait(&mutex->cond, &mutex->lock); |
| 147 | mutex->waiters--; |
| 148 | } |
| 149 | |
| 150 | mutex->value--; |
| 151 | pthread_mutex_unlock(&mutex->lock); |
| 152 | } |
| 153 | |
| 154 | void fio_mutex_down_read(struct fio_mutex *mutex) |
| 155 | { |
| 156 | pthread_mutex_lock(&mutex->lock); |
| 157 | |
| 158 | while (mutex->value < 0) { |
| 159 | mutex->waiters++; |
| 160 | pthread_cond_wait(&mutex->cond, &mutex->lock); |
| 161 | mutex->waiters--; |
| 162 | } |
| 163 | |
| 164 | mutex->value++; |
| 165 | pthread_mutex_unlock(&mutex->lock); |
| 166 | } |
| 167 | |
| 168 | void fio_mutex_up_read(struct fio_mutex *mutex) |
| 169 | { |
| 170 | pthread_mutex_lock(&mutex->lock); |
| 171 | mutex->value--; |
| 172 | read_barrier(); |
| 173 | if (mutex->value >= 0 && mutex->waiters) |
| 174 | pthread_cond_signal(&mutex->cond); |
| 175 | pthread_mutex_unlock(&mutex->lock); |
| 176 | } |
| 177 | |
| 178 | void fio_mutex_up_write(struct fio_mutex *mutex) |
| 179 | { |
| 180 | pthread_mutex_lock(&mutex->lock); |
| 181 | mutex->value++; |
| 182 | read_barrier(); |
| 183 | if (mutex->value >= 0 && mutex->waiters) |
| 184 | pthread_cond_signal(&mutex->cond); |
| 185 | pthread_mutex_unlock(&mutex->lock); |
| 186 | } |