src/util/u_thread.h

   1 /**************************************************************************
   2  *
   3  * Copyright 1999-2006 Brian Paul
   4  * Copyright 2008 VMware, Inc.
   5  * All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  **************************************************************************/
  26
  27 #ifndef U_THREAD_H_
  28 #define U_THREAD_H_
  29
  30 #include <stdint.h>
  31 #include <stdbool.h>
  32
  33 #include "c11/threads.h"
  34
  35 #ifdef HAVE_PTHREAD
  36 #include <signal.h>
  37 #endif
  38
  39
  40 static inline thrd_t u_thread_create(int (*routine)(void *), void *param)
  41 {
  42    thrd_t thread;
  43 #ifdef HAVE_PTHREAD
  44    sigset_t saved_set, new_set;
  45    int ret;
  46
  47    sigfillset(&new_set);
  48    pthread_sigmask(SIG_SETMASK, &new_set, &saved_set);
  49    ret = thrd_create( &thread, routine, param );
  50    pthread_sigmask(SIG_SETMASK, &saved_set, NULL);
  51 #else
  52    int ret;
  53    ret = thrd_create( &thread, routine, param );
  54 #endif
  55    if (ret)
  56       return 0;
  57
  58    return thread;
  59 }
  60
  61 static inline void u_thread_setname( const char *name )
  62 {
  63 #if defined(HAVE_PTHREAD)
  64 #  if defined(__GNU_LIBRARY__) && defined(__GLIBC__) && defined(__GLIBC_MINOR__) && \
  65       (__GLIBC__ >= 3 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 12)) && \
  66       defined(__linux__)
  67    pthread_setname_np(pthread_self(), name);
  68 #  endif
  69 #endif
  70    (void)name;
  71 }
  72
  73 /*
  74  * Thread statistics.
  75  */
  76
  77 /* Return the time of a thread's CPU time clock. */
  78 static inline int64_t
  79 u_thread_get_time_nano(thrd_t thread)
  80 {
  81 #if defined(__linux__) && defined(HAVE_PTHREAD)
  82    struct timespec ts;
  83    clockid_t cid;
  84
  85    pthread_getcpuclockid(thread, &cid);
  86    clock_gettime(cid, &ts);
  87    return (int64_t)ts.tv_sec * 1000000000 + ts.tv_nsec;
  88 #else
  89    return 0;
  90 #endif
  91 }
  92
  93 static inline bool u_thread_is_self(thrd_t thread)
  94 {
  95 #if defined(HAVE_PTHREAD)
  96 #  if defined(__GNU_LIBRARY__) && defined(__GLIBC__) && defined(__GLIBC_MINOR__) && \
  97       (__GLIBC__ >= 3 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 12))
  98    return pthread_equal(pthread_self(), thread);
  99 #  endif
 100 #endif
 101    return false;
 102 }
 103
 104 /*
 105  * util_barrier
 106  */
 107
 108 #if defined(HAVE_PTHREAD) && !defined(__APPLE__)
 109
 110 typedef pthread_barrier_t util_barrier;
 111
 112 static inline void util_barrier_init(util_barrier *barrier, unsigned count)
 113 {
 114    pthread_barrier_init(barrier, NULL, count);
 115 }
 116
 117 static inline void util_barrier_destroy(util_barrier *barrier)
 118 {
 119    pthread_barrier_destroy(barrier);
 120 }
 121
 122 static inline void util_barrier_wait(util_barrier *barrier)
 123 {
 124    pthread_barrier_wait(barrier);
 125 }
 126
 127
 128 #else /* If the OS doesn't have its own, implement barriers using a mutex and a condvar */
 129
 130 typedef struct {
 131    unsigned count;
 132    unsigned waiters;
 133    uint64_t sequence;
 134    mtx_t mutex;
 135    cnd_t condvar;
 136 } util_barrier;
 137
 138 static inline void util_barrier_init(util_barrier *barrier, unsigned count)
 139 {
 140    barrier->count = count;
 141    barrier->waiters = 0;
 142    barrier->sequence = 0;
 143    (void) mtx_init(&barrier->mutex, mtx_plain);
 144    cnd_init(&barrier->condvar);
 145 }
 146
 147 static inline void util_barrier_destroy(util_barrier *barrier)
 148 {
 149    assert(barrier->waiters == 0);
 150    mtx_destroy(&barrier->mutex);
 151    cnd_destroy(&barrier->condvar);
 152 }
 153
 154 static inline void util_barrier_wait(util_barrier *barrier)
 155 {
 156    mtx_lock(&barrier->mutex);
 157
 158    assert(barrier->waiters < barrier->count);
 159    barrier->waiters++;
 160
 161    if (barrier->waiters < barrier->count) {
 162       uint64_t sequence = barrier->sequence;
 163
 164       do {
 165          cnd_wait(&barrier->condvar, &barrier->mutex);
 166       } while (sequence == barrier->sequence);
 167    } else {
 168       barrier->waiters = 0;
 169       barrier->sequence++;
 170       cnd_broadcast(&barrier->condvar);
 171    }
 172
 173    mtx_unlock(&barrier->mutex);
 174 }
 175
 176 #endif
 177
 178 #endif /* U_THREAD_H_ */