nptl/tst-mutex-errorcheck.c

   1 /* Check that error checking mutexes are not subject to lock elision.
   2    Copyright (C) 2016-2018 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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 #include <stdio.h>
  20 #include <errno.h>
  21 #include <time.h>
  22 #include <pthread.h>
  23
  24 static int
  25 do_test (void)
  26 {
  27   struct timespec tms = { 0 };
  28   pthread_mutex_t mutex;
  29   pthread_mutexattr_t mutexattr;
  30   int ret = 0;
  31
  32   if (pthread_mutexattr_init (&mutexattr) != 0)
  33     return 1;
  34   if (pthread_mutexattr_settype (&mutexattr, PTHREAD_MUTEX_ERRORCHECK) != 0)
  35     return 1;
  36
  37   if (pthread_mutex_init (&mutex, &mutexattr) != 0)
  38     return 1;
  39   if (pthread_mutexattr_destroy (&mutexattr) != 0)
  40     return 1;
  41
  42   /* The call to pthread_mutex_timedlock erroneously enabled lock elision
  43      on the mutex, which then triggered an assertion failure in
  44      pthread_mutex_unlock.  It would also defeat the error checking nature
  45      of the mutex.  */
  46   if (pthread_mutex_timedlock (&mutex, &tms) != 0)
  47     return 1;
  48   if (pthread_mutex_timedlock (&mutex, &tms) != EDEADLK)
  49     {
  50       printf ("Failed error checking on locked mutex\n");
  51       ret = 1;
  52     }
  53
  54   if (pthread_mutex_unlock (&mutex) != 0)
  55     ret = 1;
  56
  57   return ret;
  58 }
  59
  60 #define TEST_FUNCTION do_test ()
  61 #include "../test-skeleton.c"