qemu-thread-posix.c

   1 /*
   2  * Wrappers around mutex/cond/thread functions
   3  *
   4  * Copyright Red Hat, Inc. 2009
   5  *
   6  * Author:
   7  *  Marcelo Tosatti <mtosatti@redhat.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10  * See the COPYING file in the top-level directory.
  11  *
  12  */
  13 #include <stdlib.h>
  14 #include <stdio.h>
  15 #include <errno.h>
  16 #include <time.h>
  17 #include <signal.h>
  18 #include <stdint.h>
  19 #include <string.h>
  20 #include "qemu-thread.h"
  21
  22 static void error_exit(int err, const char *msg)
  23 {
  24     fprintf(stderr, "qemu: %s: %s\n", msg, strerror(err));
  25     exit(1);
  26 }
  27
  28 void qemu_mutex_init(QemuMutex *mutex)
  29 {
  30     int err;
  31     pthread_mutexattr_t mutexattr;
  32
  33     pthread_mutexattr_init(&mutexattr);
  34     pthread_mutexattr_settype(&mutexattr, PTHREAD_MUTEX_ERRORCHECK);
  35     err = pthread_mutex_init(&mutex->lock, &mutexattr);
  36     pthread_mutexattr_destroy(&mutexattr);
  37     if (err)
  38         error_exit(err, __func__);
  39 }
  40
  41 void qemu_mutex_destroy(QemuMutex *mutex)
  42 {
  43     int err;
  44
  45     err = pthread_mutex_destroy(&mutex->lock);
  46     if (err)
  47         error_exit(err, __func__);
  48 }
  49
  50 void qemu_mutex_lock(QemuMutex *mutex)
  51 {
  52     int err;
  53
  54     err = pthread_mutex_lock(&mutex->lock);
  55     if (err)
  56         error_exit(err, __func__);
  57 }
  58
  59 int qemu_mutex_trylock(QemuMutex *mutex)
  60 {
  61     return pthread_mutex_trylock(&mutex->lock);
  62 }
  63
  64 static void timespec_add_ms(struct timespec *ts, uint64_t msecs)
  65 {
  66     ts->tv_sec = ts->tv_sec + (long)(msecs / 1000);
  67     ts->tv_nsec = (ts->tv_nsec + ((long)msecs % 1000) * 1000000);
  68     if (ts->tv_nsec >= 1000000000) {
  69         ts->tv_nsec -= 1000000000;
  70         ts->tv_sec++;
  71     }
  72 }
  73
  74 int qemu_mutex_timedlock(QemuMutex *mutex, uint64_t msecs)
  75 {
  76     int err;
  77     struct timespec ts;
  78
  79     clock_gettime(CLOCK_REALTIME, &ts);
  80     timespec_add_ms(&ts, msecs);
  81
  82     err = pthread_mutex_timedlock(&mutex->lock, &ts);
  83     if (err && err != ETIMEDOUT)
  84         error_exit(err, __func__);
  85     return err;
  86 }
  87
  88 void qemu_mutex_unlock(QemuMutex *mutex)
  89 {
  90     int err;
  91
  92     err = pthread_mutex_unlock(&mutex->lock);
  93     if (err)
  94         error_exit(err, __func__);
  95 }
  96
  97 void qemu_cond_init(QemuCond *cond)
  98 {
  99     int err;
 100
 101     err = pthread_cond_init(&cond->cond, NULL);
 102     if (err)
 103         error_exit(err, __func__);
 104 }
 105
 106 void qemu_cond_destroy(QemuCond *cond)
 107 {
 108     int err;
 109
 110     err = pthread_cond_destroy(&cond->cond);
 111     if (err)
 112         error_exit(err, __func__);
 113 }
 114
 115 void qemu_cond_signal(QemuCond *cond)
 116 {
 117     int err;
 118
 119     err = pthread_cond_signal(&cond->cond);
 120     if (err)
 121         error_exit(err, __func__);
 122 }
 123
 124 void qemu_cond_broadcast(QemuCond *cond)
 125 {
 126     int err;
 127
 128     err = pthread_cond_broadcast(&cond->cond);
 129     if (err)
 130         error_exit(err, __func__);
 131 }
 132
 133 void qemu_cond_wait(QemuCond *cond, QemuMutex *mutex)
 134 {
 135     int err;
 136
 137     err = pthread_cond_wait(&cond->cond, &mutex->lock);
 138     if (err)
 139         error_exit(err, __func__);
 140 }
 141
 142 int qemu_cond_timedwait(QemuCond *cond, QemuMutex *mutex, uint64_t msecs)
 143 {
 144     struct timespec ts;
 145     int err;
 146
 147     clock_gettime(CLOCK_REALTIME, &ts);
 148     timespec_add_ms(&ts, msecs);
 149
 150     err = pthread_cond_timedwait(&cond->cond, &mutex->lock, &ts);
 151     if (err && err != ETIMEDOUT)
 152         error_exit(err, __func__);
 153     return err;
 154 }
 155
 156 void qemu_thread_create(QemuThread *thread,
 157                        void *(*start_routine)(void*),
 158                        void *arg)
 159 {
 160     int err;
 161
 162     /* Leave signal handling to the iothread.  */
 163     sigset_t set, oldset;
 164
 165     sigfillset(&set);
 166     pthread_sigmask(SIG_SETMASK, &set, &oldset);
 167     err = pthread_create(&thread->thread, NULL, start_routine, arg);
 168     if (err)
 169         error_exit(err, __func__);
 170
 171     pthread_sigmask(SIG_SETMASK, &oldset, NULL);
 172 }
 173
 174 void qemu_thread_get_self(QemuThread *thread)
 175 {
 176     thread->thread = pthread_self();
 177 }
 178
 179 int qemu_thread_is_self(QemuThread *thread)
 180 {
 181    return pthread_equal(pthread_self(), thread->thread);
 182 }
 183
 184 void qemu_thread_exit(void *retval)
 185 {
 186     pthread_exit(retval);
 187 }