regress/lib/libpthread/barrier1/barrier1.c

   1 /*      $NetBSD: barrier1.c,v 1.2 2006/12/23 17:44:12 ad Exp $  */
   2
   3 #include <assert.h>
   4 #include <err.h>
   5 #include <pthread.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <unistd.h>
   9
  10 void *threadfunc(void *arg);
  11
  12 pthread_barrier_t barrier;
  13 pthread_mutex_t mutex;
  14 int serial_count;
  15 int after_barrier_count;
  16
  17 #define COUNT   10
  18
  19 int
  20 main(int argc, char *argv[])
  21 {
  22         int i, ret;
  23         pthread_t new[COUNT];
  24         void *joinval;
  25
  26         pthread_mutex_init(&mutex, NULL);
  27
  28         ret = pthread_barrier_init(&barrier, NULL, COUNT);
  29         if (ret != 0)
  30                 err(1, "pthread_barrier_init");
  31
  32         for (i = 0; i < COUNT; i++) {
  33                 pthread_mutex_lock(&mutex);
  34                 assert(after_barrier_count == 0);
  35                 pthread_mutex_unlock(&mutex);
  36                 ret = pthread_create(&new[i], NULL, threadfunc,
  37                     (void *)(long)i);
  38                 if (ret != 0)
  39                         err(1, "pthread_create");
  40                 sleep(2);
  41         }
  42
  43         for (i = 0; i < COUNT; i++) {
  44                 ret = pthread_join(new[i], &joinval);
  45                 if (ret != 0)
  46                         err(1, "pthread_join: %d", ret);
  47                 pthread_mutex_lock(&mutex);
  48                 assert(after_barrier_count > i);
  49                 pthread_mutex_unlock(&mutex);
  50                 printf("main joined with thread %d\n", i);
  51         }
  52
  53         pthread_mutex_lock(&mutex);
  54         assert(after_barrier_count == COUNT);
  55         pthread_mutex_unlock(&mutex);
  56         assert(serial_count == 1);
  57
  58         return 0;
  59 }
  60
  61 void *
  62 threadfunc(void *arg)
  63 {
  64         int which = (int)(long)arg;
  65         int ret;
  66
  67         printf("thread %d entering barrier\n", which);
  68         ret = pthread_barrier_wait(&barrier);
  69         printf("thread %d leaving barrier -> %d\n", which, ret);
  70
  71         pthread_mutex_lock(&mutex);
  72         after_barrier_count++;
  73         if (ret == PTHREAD_BARRIER_SERIAL_THREAD)
  74                 serial_count++;
  75         pthread_mutex_unlock(&mutex);
  76
  77         return NULL;
  78 }