| /* Copyright (C) 2003-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <errno.h> |
| #include <sysdep.h> |
| #include <futex-internal.h> |
| #include <pthread.h> |
| #include <pthreadP.h> |
| #include <stap-probe.h> |
| |
| #include "pthread_rwlock_common.c" |
| |
| /* See pthread_rwlock_common.c for an overview. */ |
| int |
| __pthread_rwlock_unlock (pthread_rwlock_t *rwlock) |
| { |
| LIBC_PROBE (rwlock_unlock, 1, rwlock); |
| |
| /* We distinguish between having acquired a read vs. a write lock by looking |
| at the writer TID. If it's equal to our TID, we must be the writer |
| because nobody else can have stored this value. Also, if we are a |
| reader, we will read from the wrunlock store with value 0 by the most |
| recent writer because that writer happens-before us. */ |
| if (atomic_load_relaxed (&rwlock->__data.__cur_writer) |
| == THREAD_GETMEM (THREAD_SELF, tid)) |
| __pthread_rwlock_wrunlock (rwlock); |
| else |
| __pthread_rwlock_rdunlock (rwlock); |
| return 0; |
| } |
| |
| weak_alias (__pthread_rwlock_unlock, pthread_rwlock_unlock) |
| hidden_def (__pthread_rwlock_unlock) |
