sysdeps/pthread/tst-cond18.c

   1 /* Copyright (C) 2004-2021 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <limits.h>
  20 #include <fcntl.h>
  21 #include <pthread.h>
  22 #include <stdbool.h>
  23 #include <stdlib.h>
  24 #include <stdio.h>
  25 #include <unistd.h>
  26
  27 pthread_cond_t cv = PTHREAD_COND_INITIALIZER;
  28 pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
  29 bool exiting;
  30 int fd, spins, nn;
  31 enum { count = 8 };             /* Number of worker threads.  */
  32
  33 void *
  34 tf (void *id)
  35 {
  36   pthread_mutex_lock (&lock);
  37
  38   if ((long) id == 0)
  39     {
  40       while (!exiting)
  41         {
  42           if ((spins++ % 1000) == 0)
  43             write (fd, ".", 1);
  44           pthread_mutex_unlock (&lock);
  45
  46           pthread_mutex_lock (&lock);
  47           int njobs = rand () % (count + 1);
  48           nn = njobs;
  49           if ((rand () % 30) == 0)
  50             pthread_cond_broadcast (&cv);
  51           else
  52             while (njobs--)
  53               pthread_cond_signal (&cv);
  54         }
  55
  56       pthread_cond_broadcast (&cv);
  57     }
  58   else
  59     {
  60       while (!exiting)
  61         {
  62           while (!nn && !exiting)
  63             pthread_cond_wait (&cv, &lock);
  64           --nn;
  65           pthread_mutex_unlock (&lock);
  66
  67           pthread_mutex_lock (&lock);
  68         }
  69     }
  70
  71   pthread_mutex_unlock (&lock);
  72   return NULL;
  73 }
  74
  75 int
  76 do_test (void)
  77 {
  78   fd = open ("/dev/null", O_WRONLY);
  79   if (fd < 0)
  80     {
  81       printf ("couldn't open /dev/null, %m\n");
  82       return 1;
  83     }
  84
  85   pthread_t th[count + 1];
  86   pthread_attr_t attr;
  87   int i, ret, sz;
  88   pthread_attr_init (&attr);
  89   sz = sysconf (_SC_PAGESIZE);
  90 #ifdef PTHREAD_STACK_MIN
  91   if (sz < PTHREAD_STACK_MIN)
  92           sz = PTHREAD_STACK_MIN;
  93 #endif
  94   pthread_attr_setstacksize (&attr, sz);
  95
  96   for (i = 0; i <= count; ++i)
  97     if ((ret = pthread_create (&th[i], &attr, tf, (void *) (long) i)) != 0)
  98       {
  99         errno = ret;
 100         printf ("pthread_create %d failed: %m\n", i);
 101         return 1;
 102       }
 103
 104   struct timespec ts = { .tv_sec = 20, .tv_nsec = 0 };
 105   while (nanosleep (&ts, &ts) != 0);
 106
 107   pthread_mutex_lock (&lock);
 108   exiting = true;
 109   pthread_mutex_unlock (&lock);
 110
 111   for (i = 0; i < count; ++i)
 112     pthread_join (th[i], NULL);
 113
 114   close (fd);
 115   return 0;
 116 }
 117
 118 #define TEST_FUNCTION do_test ()
 119 #define TIMEOUT 40
 120 #include "../test-skeleton.c"