222 lines
6.4 KiB
C
222 lines
6.4 KiB
C
/* Copyright (C) 2002, 2003, 2005, 2006 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <errno.h>
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#include <stdlib.h>
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#include "pthreadP.h"
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#include <lowlevellock.h>
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int
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internal_function attribute_hidden
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__pthread_mutex_unlock_usercnt (mutex, decr)
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pthread_mutex_t *mutex;
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int decr;
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{
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int newowner = 0;
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switch (__builtin_expect (mutex->__data.__kind, PTHREAD_MUTEX_TIMED_NP))
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{
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case PTHREAD_MUTEX_RECURSIVE_NP:
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/* Recursive mutex. */
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if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
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return EPERM;
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if (--mutex->__data.__count != 0)
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/* We still hold the mutex. */
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return 0;
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goto normal;
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case PTHREAD_MUTEX_ERRORCHECK_NP:
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/* Error checking mutex. */
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if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)
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|| ! lll_mutex_islocked (mutex->__data.__lock))
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return EPERM;
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/* FALLTHROUGH */
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case PTHREAD_MUTEX_TIMED_NP:
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case PTHREAD_MUTEX_ADAPTIVE_NP:
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/* Always reset the owner field. */
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normal:
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mutex->__data.__owner = 0;
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if (decr)
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/* One less user. */
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--mutex->__data.__nusers;
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/* Unlock. */
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lll_mutex_unlock (mutex->__data.__lock);
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break;
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case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP:
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/* Recursive mutex. */
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if ((mutex->__data.__lock & FUTEX_TID_MASK)
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== THREAD_GETMEM (THREAD_SELF, tid)
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&& __builtin_expect (mutex->__data.__owner
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== PTHREAD_MUTEX_INCONSISTENT, 0))
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{
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if (--mutex->__data.__count != 0)
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/* We still hold the mutex. */
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return ENOTRECOVERABLE;
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goto notrecoverable;
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}
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if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
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return EPERM;
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if (--mutex->__data.__count != 0)
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/* We still hold the mutex. */
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return 0;
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goto robust;
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case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP:
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case PTHREAD_MUTEX_ROBUST_NORMAL_NP:
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case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP:
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if ((mutex->__data.__lock & FUTEX_TID_MASK)
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!= THREAD_GETMEM (THREAD_SELF, tid)
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|| ! lll_mutex_islocked (mutex->__data.__lock))
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return EPERM;
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/* If the previous owner died and the caller did not succeed in
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making the state consistent, mark the mutex as unrecoverable
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and make all waiters. */
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if (__builtin_expect (mutex->__data.__owner
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== PTHREAD_MUTEX_INCONSISTENT, 0))
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notrecoverable:
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newowner = PTHREAD_MUTEX_NOTRECOVERABLE;
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robust:
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/* Remove mutex from the list. */
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THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
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&mutex->__data.__list.__next);
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DEQUEUE_MUTEX (mutex);
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mutex->__data.__owner = newowner;
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if (decr)
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/* One less user. */
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--mutex->__data.__nusers;
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/* Unlock. */
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lll_robust_mutex_unlock (mutex->__data.__lock);
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THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
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break;
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case PTHREAD_MUTEX_PI_RECURSIVE_NP:
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/* Recursive mutex. */
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if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
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return EPERM;
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if (--mutex->__data.__count != 0)
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/* We still hold the mutex. */
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return 0;
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goto continue_pi;
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case PTHREAD_MUTEX_PI_ROBUST_RECURSIVE_NP:
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/* Recursive mutex. */
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if ((mutex->__data.__lock & FUTEX_TID_MASK)
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== THREAD_GETMEM (THREAD_SELF, tid)
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&& __builtin_expect (mutex->__data.__owner
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== PTHREAD_MUTEX_INCONSISTENT, 0))
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{
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if (--mutex->__data.__count != 0)
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/* We still hold the mutex. */
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return ENOTRECOVERABLE;
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goto pi_notrecoverable;
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}
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if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
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return EPERM;
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if (--mutex->__data.__count != 0)
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/* We still hold the mutex. */
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return 0;
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goto continue_pi;
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case PTHREAD_MUTEX_PI_ERRORCHECK_NP:
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case PTHREAD_MUTEX_PI_NORMAL_NP:
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case PTHREAD_MUTEX_PI_ADAPTIVE_NP:
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case PTHREAD_MUTEX_PI_ROBUST_ERRORCHECK_NP:
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case PTHREAD_MUTEX_PI_ROBUST_NORMAL_NP:
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case PTHREAD_MUTEX_PI_ROBUST_ADAPTIVE_NP:
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if ((mutex->__data.__lock & FUTEX_TID_MASK)
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!= THREAD_GETMEM (THREAD_SELF, tid)
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|| ! lll_mutex_islocked (mutex->__data.__lock))
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return EPERM;
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/* If the previous owner died and the caller did not succeed in
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making the state consistent, mark the mutex as unrecoverable
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and make all waiters. */
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if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) != 0
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&& __builtin_expect (mutex->__data.__owner
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== PTHREAD_MUTEX_INCONSISTENT, 0))
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pi_notrecoverable:
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newowner = PTHREAD_MUTEX_NOTRECOVERABLE;
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continue_pi:
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if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) != 0)
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{
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/* Remove mutex from the list.
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Note: robust PI futexes are signaled by setting bit 0. */
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THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
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(void *) (((uintptr_t) &mutex->__data.__list.__next)
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| 1));
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DEQUEUE_MUTEX (mutex);
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}
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mutex->__data.__owner = newowner;
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if (decr)
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/* One less user. */
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--mutex->__data.__nusers;
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/* Unlock. */
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if ((mutex->__data.__lock & FUTEX_WAITERS) != 0
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|| atomic_compare_and_exchange_bool_acq (&mutex->__data.__lock, 0,
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THREAD_GETMEM (THREAD_SELF,
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tid)))
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{
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INTERNAL_SYSCALL_DECL (__err);
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INTERNAL_SYSCALL (futex, __err, 2, &mutex->__data.__lock,
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FUTEX_UNLOCK_PI);
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}
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THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
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break;
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default:
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/* Correct code cannot set any other type. */
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return EINVAL;
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}
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return 0;
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}
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int
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__pthread_mutex_unlock (mutex)
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pthread_mutex_t *mutex;
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{
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return __pthread_mutex_unlock_usercnt (mutex, 1);
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}
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strong_alias (__pthread_mutex_unlock, pthread_mutex_unlock)
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strong_alias (__pthread_mutex_unlock, __pthread_mutex_unlock_internal)
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