sysdeps/pthread/tst-mutex-errorcheck.c

   1 /* Check that error checking mutexes are not subject to lock elision.
   2    Copyright (C) 2016-2020 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    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <stdio.h>
  20 #include <errno.h>
  21 #include <time.h>
  22 #include <pthread.h>
  23 #include <support/check.h>
  24
  25 static int
  26 do_test (void)
  27 {
  28   struct timespec tms = { 0 };
  29   pthread_mutex_t mutex;
  30   pthread_mutexattr_t mutexattr;
  31   int ret = 0;
  32
  33   TEST_COMPARE (pthread_mutexattr_init (&mutexattr), 0);
  34   TEST_COMPARE (pthread_mutexattr_settype (&mutexattr,
  35                                            PTHREAD_MUTEX_ERRORCHECK), 0);
  36
  37   TEST_COMPARE (pthread_mutex_init (&mutex, &mutexattr), 0);
  38   TEST_COMPARE (pthread_mutexattr_destroy (&mutexattr), 0);
  39
  40   /* The call to pthread_mutex_timedlock erroneously enabled lock elision
  41      on the mutex, which then triggered an assertion failure in
  42      pthread_mutex_unlock.  It would also defeat the error checking nature
  43      of the mutex.  */
  44   TEST_COMPARE (pthread_mutex_timedlock (&mutex, &tms), 0);
  45   TEST_COMPARE (pthread_mutex_timedlock (&mutex, &tms), EDEADLK);
  46
  47   TEST_COMPARE (pthread_mutex_unlock (&mutex), 0);
  48
  49   return ret;
  50 }
  51
  52 #include <support/test-driver.c>