Style fixups
[fio.git] / mutex.c
CommitLineData
07739b57
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1#include <stdio.h>
2#include <string.h>
3#include <unistd.h>
4#include <stdlib.h>
5#include <fcntl.h>
6#include <pthread.h>
7#include <sys/mman.h>
8
9#include "mutex.h"
4d4e80f2 10#include "arch/arch.h"
07739b57 11
cdd18ad8 12void fio_mutex_remove(struct fio_mutex *mutex)
07739b57 13{
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14 close(mutex->mutex_fd);
15 munmap(mutex, sizeof(*mutex));
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16}
17
cdd18ad8 18struct fio_mutex *fio_mutex_init(int value)
07739b57 19{
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20 char mutex_name[] = "/tmp/.fio_mutex.XXXXXX";
21 struct fio_mutex *mutex = NULL;
07739b57 22 pthread_mutexattr_t attr;
108fcc11 23 pthread_condattr_t cond;
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24 int fd;
25
cdd18ad8 26 fd = mkstemp(mutex_name);
07739b57 27 if (fd < 0) {
cdd18ad8 28 perror("open mutex");
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29 return NULL;
30 }
31
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32 if (ftruncate(fd, sizeof(struct fio_mutex)) < 0) {
33 perror("ftruncate mutex");
e53bd0b3 34 goto err;
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35 }
36
cdd18ad8 37 mutex = mmap(NULL, sizeof(struct fio_mutex), PROT_READ | PROT_WRITE,
07739b57 38 MAP_SHARED, fd, 0);
cdd18ad8
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39 if (mutex == MAP_FAILED) {
40 perror("mmap mutex");
07739b57 41 close(fd);
cdd18ad8 42 mutex = NULL;
e53bd0b3 43 goto err;
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44 }
45
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46 unlink(mutex_name);
47 mutex->mutex_fd = fd;
48 mutex->value = value;
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49
50 if (pthread_mutexattr_init(&attr)) {
51 perror("pthread_mutexattr_init");
52 goto err;
53 }
54 if (pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED)) {
55 perror("pthread_mutexattr_setpshared");
56 goto err;
57 }
108fcc11
ZY
58
59 pthread_condattr_init(&cond);
60 pthread_condattr_setpshared(&cond, PTHREAD_PROCESS_SHARED);
cdd18ad8 61 pthread_cond_init(&mutex->cond, &cond);
108fcc11 62
cdd18ad8 63 if (pthread_mutex_init(&mutex->lock, &attr)) {
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64 perror("pthread_mutex_init");
65 goto err;
66 }
67
cdd18ad8 68 return mutex;
07739b57 69err:
cdd18ad8
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70 if (mutex)
71 fio_mutex_remove(mutex);
f7c9e00e 72
cdd18ad8 73 unlink(mutex_name);
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74 return NULL;
75}
76
cdd18ad8 77void fio_mutex_down(struct fio_mutex *mutex)
07739b57 78{
cdd18ad8 79 pthread_mutex_lock(&mutex->lock);
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80
81 while (!mutex->value) {
82 mutex->waiters++;
cdd18ad8 83 pthread_cond_wait(&mutex->cond, &mutex->lock);
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84 mutex->waiters--;
85 }
86
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87 mutex->value--;
88 pthread_mutex_unlock(&mutex->lock);
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89}
90
cdd18ad8 91void fio_mutex_up(struct fio_mutex *mutex)
07739b57 92{
cdd18ad8 93 pthread_mutex_lock(&mutex->lock);
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94 read_barrier();
95 if (!mutex->value && mutex->waiters)
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96 pthread_cond_signal(&mutex->cond);
97 mutex->value++;
98 pthread_mutex_unlock(&mutex->lock);
07739b57 99}
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100
101void fio_mutex_down_write(struct fio_mutex *mutex)
102{
103 pthread_mutex_lock(&mutex->lock);
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104
105 while (mutex->value != 0) {
106 mutex->waiters++;
64d4d313 107 pthread_cond_wait(&mutex->cond, &mutex->lock);
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108 mutex->waiters--;
109 }
110
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111 mutex->value--;
112 pthread_mutex_unlock(&mutex->lock);
113}
114
115void fio_mutex_down_read(struct fio_mutex *mutex)
116{
117 pthread_mutex_lock(&mutex->lock);
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118
119 while (mutex->value < 0) {
120 mutex->waiters++;
64d4d313 121 pthread_cond_wait(&mutex->cond, &mutex->lock);
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122 mutex->waiters--;
123 }
124
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125 mutex->value++;
126 pthread_mutex_unlock(&mutex->lock);
127}
128
129void fio_mutex_up_read(struct fio_mutex *mutex)
130{
131 pthread_mutex_lock(&mutex->lock);
132 mutex->value--;
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133 read_barrier();
134 if (mutex->value >= 0 && mutex->waiters)
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135 pthread_cond_signal(&mutex->cond);
136 pthread_mutex_unlock(&mutex->lock);
137}
138
139void fio_mutex_up_write(struct fio_mutex *mutex)
140{
141 pthread_mutex_lock(&mutex->lock);
142 mutex->value++;
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143 read_barrier();
144 if (mutex->value >= 0 && mutex->waiters)
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145 pthread_cond_signal(&mutex->cond);
146 pthread_mutex_unlock(&mutex->lock);
147}