nptl/pthread_mutex_consistent.c

   1 /* Copyright (C) 2005-2020 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2005.
   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 <errno.h>
  20 #include <pthreadP.h>
  21
  22
  23 int
  24 pthread_mutex_consistent (pthread_mutex_t *mutex)
  25 {
  26   /* Test whether this is a robust mutex with a dead owner.
  27      See concurrency notes regarding __kind in struct __pthread_mutex_s
  28      in sysdeps/nptl/bits/thread-shared-types.h.  */
  29   if ((atomic_load_relaxed (&(mutex->__data.__kind))
  30        & PTHREAD_MUTEX_ROBUST_NORMAL_NP) == 0
  31       || mutex->__data.__owner != PTHREAD_MUTEX_INCONSISTENT)
  32     return EINVAL;
  33
  34   mutex->__data.__owner = THREAD_GETMEM (THREAD_SELF, tid);
  35
  36   return 0;
  37 }
  38 weak_alias (pthread_mutex_consistent, pthread_mutex_consistent_np)