nptl/tst-barrier3.c

   1 /* Copyright (C) 2002-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 /* Test of POSIX barriers.  */
  20
  21 #include <pthread.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #define NTHREADS 20
  27
  28 #define ROUNDS 20
  29
  30 static pthread_barrier_t barriers[NTHREADS];
  31
  32 static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
  33 static int counters[NTHREADS];
  34 static int serial[NTHREADS];
  35
  36 static void *
  37 worker (void *arg)
  38 {
  39   void *result = NULL;
  40   int nr = (long int) arg;
  41   int i;
  42
  43   for (i = 0; i < ROUNDS; ++i)
  44     {
  45       int j;
  46       int retval;
  47
  48       if (nr == 0)
  49         {
  50           memset (counters, '\0', sizeof (counters));
  51           memset (serial, '\0', sizeof (serial));
  52         }
  53
  54       retval = pthread_barrier_wait (&barriers[NTHREADS - 1]);
  55       if (retval != 0 && retval != PTHREAD_BARRIER_SERIAL_THREAD)
  56         {
  57           printf ("thread %d failed to wait for all the others\n", nr);
  58           result = (void *) 1;
  59         }
  60
  61       for (j = nr; j < NTHREADS; ++j)
  62         {
  63           /* Increment the counter for this round.  */
  64           pthread_mutex_lock (&lock);
  65           ++counters[j];
  66           pthread_mutex_unlock (&lock);
  67
  68           /* Wait for the rest.  */
  69           retval = pthread_barrier_wait (&barriers[j]);
  70
  71           /* Test the result.  */
  72           if (nr == 0 && counters[j] != j + 1)
  73             {
  74               printf ("barrier in round %d released but count is %d\n",
  75                       j, counters[j]);
  76               result = (void *) 1;
  77             }
  78
  79           if (retval != 0)
  80             {
  81               if (retval != PTHREAD_BARRIER_SERIAL_THREAD)
  82                 {
  83                   printf ("thread %d in round %d has nonzero return value != PTHREAD_BARRIER_SERIAL_THREAD\n",
  84                           nr, j);
  85                   result = (void *) 1;
  86                 }
  87               else
  88                 {
  89                   pthread_mutex_lock (&lock);
  90                   ++serial[j];
  91                   pthread_mutex_unlock (&lock);
  92                 }
  93             }
  94
  95           /* Wait for the rest again.  */
  96           retval = pthread_barrier_wait (&barriers[j]);
  97
  98           /* Now we can check whether exactly one thread was serializing.  */
  99           if (nr == 0 && serial[j] != 1)
 100             {
 101               printf ("not exactly one serial thread in round %d\n", j);
 102               result = (void *) 1;
 103             }
 104         }
 105     }
 106
 107   return result;
 108 }
 109
 110
 111 #define TEST_FUNCTION do_test ()
 112 #define TIMEOUT 60
 113 static int
 114 do_test (void)
 115 {
 116   pthread_t threads[NTHREADS];
 117   int i;
 118   void *res;
 119   int result = 0;
 120
 121   /* Initialized the barrier variables.  */
 122   for (i = 0; i < NTHREADS; ++i)
 123     if (pthread_barrier_init (&barriers[i], NULL, i + 1) != 0)
 124       {
 125         printf ("Failed to initialize barrier %d\n", i);
 126         exit (1);
 127       }
 128
 129   /* Start the threads.  */
 130   for (i = 0; i < NTHREADS; ++i)
 131     if (pthread_create (&threads[i], NULL, worker, (void *) (long int) i) != 0)
 132       {
 133         printf ("Failed to start thread %d\n", i);
 134         exit (1);
 135       }
 136
 137   /* And wait for them.  */
 138   for (i = 0; i < NTHREADS; ++i)
 139     if (pthread_join (threads[i], &res) != 0 || res != NULL)
 140       {
 141         printf ("thread %d returned a failure\n", i);
 142         result = 1;
 143       }
 144     else
 145       printf ("joined threads %d\n", i);
 146
 147   if (result == 0)
 148     puts ("all OK");
 149
 150   return result;
 151 }
 152
 153 #include "../test-skeleton.c"