294 lines
8.5 KiB
C
294 lines
8.5 KiB
C
/* Copyright (C) 2002, 2003, 2005-2008, 2009 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
|
|
|
|
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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#include <assert.h>
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
#include "pthreadP.h"
|
|
#include <lowlevellock.h>
|
|
|
|
static int
|
|
internal_function
|
|
__pthread_mutex_unlock_full (pthread_mutex_t *mutex, int decr)
|
|
__attribute_noinline__;
|
|
|
|
int
|
|
internal_function attribute_hidden
|
|
__pthread_mutex_unlock_usercnt (mutex, decr)
|
|
pthread_mutex_t *mutex;
|
|
int decr;
|
|
{
|
|
int type = PTHREAD_MUTEX_TYPE (mutex);
|
|
if (__builtin_expect (type & ~PTHREAD_MUTEX_KIND_MASK_NP, 0))
|
|
return __pthread_mutex_unlock_full (mutex, decr);
|
|
|
|
if (__builtin_expect (type, PTHREAD_MUTEX_TIMED_NP)
|
|
== PTHREAD_MUTEX_TIMED_NP)
|
|
{
|
|
/* Always reset the owner field. */
|
|
normal:
|
|
mutex->__data.__owner = 0;
|
|
if (decr)
|
|
/* One less user. */
|
|
--mutex->__data.__nusers;
|
|
|
|
/* Unlock. */
|
|
lll_unlock (mutex->__data.__lock, PTHREAD_MUTEX_PSHARED (mutex));
|
|
return 0;
|
|
}
|
|
else if (__builtin_expect (type == PTHREAD_MUTEX_RECURSIVE_NP, 1))
|
|
{
|
|
/* Recursive mutex. */
|
|
if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
|
|
return EPERM;
|
|
|
|
if (--mutex->__data.__count != 0)
|
|
/* We still hold the mutex. */
|
|
return 0;
|
|
goto normal;
|
|
}
|
|
else if (__builtin_expect (type == PTHREAD_MUTEX_ADAPTIVE_NP, 1))
|
|
goto normal;
|
|
else
|
|
{
|
|
/* Error checking mutex. */
|
|
assert (type == PTHREAD_MUTEX_ERRORCHECK_NP);
|
|
if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)
|
|
|| ! lll_islocked (mutex->__data.__lock))
|
|
return EPERM;
|
|
goto normal;
|
|
}
|
|
}
|
|
|
|
|
|
static int
|
|
internal_function
|
|
__pthread_mutex_unlock_full (pthread_mutex_t *mutex, int decr)
|
|
{
|
|
int newowner = 0;
|
|
|
|
switch (PTHREAD_MUTEX_TYPE (mutex))
|
|
{
|
|
case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP:
|
|
/* Recursive mutex. */
|
|
if ((mutex->__data.__lock & FUTEX_TID_MASK)
|
|
== THREAD_GETMEM (THREAD_SELF, tid)
|
|
&& __builtin_expect (mutex->__data.__owner
|
|
== PTHREAD_MUTEX_INCONSISTENT, 0))
|
|
{
|
|
if (--mutex->__data.__count != 0)
|
|
/* We still hold the mutex. */
|
|
return ENOTRECOVERABLE;
|
|
|
|
goto notrecoverable;
|
|
}
|
|
|
|
if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
|
|
return EPERM;
|
|
|
|
if (--mutex->__data.__count != 0)
|
|
/* We still hold the mutex. */
|
|
return 0;
|
|
|
|
goto robust;
|
|
|
|
case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP:
|
|
case PTHREAD_MUTEX_ROBUST_NORMAL_NP:
|
|
case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP:
|
|
if ((mutex->__data.__lock & FUTEX_TID_MASK)
|
|
!= THREAD_GETMEM (THREAD_SELF, tid)
|
|
|| ! lll_islocked (mutex->__data.__lock))
|
|
return EPERM;
|
|
|
|
/* If the previous owner died and the caller did not succeed in
|
|
making the state consistent, mark the mutex as unrecoverable
|
|
and make all waiters. */
|
|
if (__builtin_expect (mutex->__data.__owner
|
|
== PTHREAD_MUTEX_INCONSISTENT, 0))
|
|
notrecoverable:
|
|
newowner = PTHREAD_MUTEX_NOTRECOVERABLE;
|
|
|
|
robust:
|
|
/* Remove mutex from the list. */
|
|
THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
|
|
&mutex->__data.__list.__next);
|
|
DEQUEUE_MUTEX (mutex);
|
|
|
|
mutex->__data.__owner = newowner;
|
|
if (decr)
|
|
/* One less user. */
|
|
--mutex->__data.__nusers;
|
|
|
|
/* Unlock. */
|
|
lll_robust_unlock (mutex->__data.__lock,
|
|
PTHREAD_ROBUST_MUTEX_PSHARED (mutex));
|
|
|
|
THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
|
|
break;
|
|
|
|
case PTHREAD_MUTEX_PI_RECURSIVE_NP:
|
|
/* Recursive mutex. */
|
|
if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
|
|
return EPERM;
|
|
|
|
if (--mutex->__data.__count != 0)
|
|
/* We still hold the mutex. */
|
|
return 0;
|
|
goto continue_pi_non_robust;
|
|
|
|
case PTHREAD_MUTEX_PI_ROBUST_RECURSIVE_NP:
|
|
/* Recursive mutex. */
|
|
if ((mutex->__data.__lock & FUTEX_TID_MASK)
|
|
== THREAD_GETMEM (THREAD_SELF, tid)
|
|
&& __builtin_expect (mutex->__data.__owner
|
|
== PTHREAD_MUTEX_INCONSISTENT, 0))
|
|
{
|
|
if (--mutex->__data.__count != 0)
|
|
/* We still hold the mutex. */
|
|
return ENOTRECOVERABLE;
|
|
|
|
goto pi_notrecoverable;
|
|
}
|
|
|
|
if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
|
|
return EPERM;
|
|
|
|
if (--mutex->__data.__count != 0)
|
|
/* We still hold the mutex. */
|
|
return 0;
|
|
|
|
goto continue_pi_robust;
|
|
|
|
case PTHREAD_MUTEX_PI_ERRORCHECK_NP:
|
|
case PTHREAD_MUTEX_PI_NORMAL_NP:
|
|
case PTHREAD_MUTEX_PI_ADAPTIVE_NP:
|
|
case PTHREAD_MUTEX_PI_ROBUST_ERRORCHECK_NP:
|
|
case PTHREAD_MUTEX_PI_ROBUST_NORMAL_NP:
|
|
case PTHREAD_MUTEX_PI_ROBUST_ADAPTIVE_NP:
|
|
if ((mutex->__data.__lock & FUTEX_TID_MASK)
|
|
!= THREAD_GETMEM (THREAD_SELF, tid)
|
|
|| ! lll_islocked (mutex->__data.__lock))
|
|
return EPERM;
|
|
|
|
/* If the previous owner died and the caller did not succeed in
|
|
making the state consistent, mark the mutex as unrecoverable
|
|
and make all waiters. */
|
|
if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) != 0
|
|
&& __builtin_expect (mutex->__data.__owner
|
|
== PTHREAD_MUTEX_INCONSISTENT, 0))
|
|
pi_notrecoverable:
|
|
newowner = PTHREAD_MUTEX_NOTRECOVERABLE;
|
|
|
|
if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) != 0)
|
|
{
|
|
continue_pi_robust:
|
|
/* Remove mutex from the list.
|
|
Note: robust PI futexes are signaled by setting bit 0. */
|
|
THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
|
|
(void *) (((uintptr_t) &mutex->__data.__list.__next)
|
|
| 1));
|
|
DEQUEUE_MUTEX (mutex);
|
|
}
|
|
|
|
continue_pi_non_robust:
|
|
mutex->__data.__owner = newowner;
|
|
if (decr)
|
|
/* One less user. */
|
|
--mutex->__data.__nusers;
|
|
|
|
/* Unlock. */
|
|
if ((mutex->__data.__lock & FUTEX_WAITERS) != 0
|
|
|| atomic_compare_and_exchange_bool_rel (&mutex->__data.__lock, 0,
|
|
THREAD_GETMEM (THREAD_SELF,
|
|
tid)))
|
|
{
|
|
int robust = mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP;
|
|
int private = (robust
|
|
? PTHREAD_ROBUST_MUTEX_PSHARED (mutex)
|
|
: PTHREAD_MUTEX_PSHARED (mutex));
|
|
INTERNAL_SYSCALL_DECL (__err);
|
|
INTERNAL_SYSCALL (futex, __err, 2, &mutex->__data.__lock,
|
|
__lll_private_flag (FUTEX_UNLOCK_PI, private));
|
|
}
|
|
|
|
THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
|
|
break;
|
|
|
|
case PTHREAD_MUTEX_PP_RECURSIVE_NP:
|
|
/* Recursive mutex. */
|
|
if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
|
|
return EPERM;
|
|
|
|
if (--mutex->__data.__count != 0)
|
|
/* We still hold the mutex. */
|
|
return 0;
|
|
goto pp;
|
|
|
|
case PTHREAD_MUTEX_PP_ERRORCHECK_NP:
|
|
/* Error checking mutex. */
|
|
if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)
|
|
|| (mutex->__data.__lock & ~ PTHREAD_MUTEX_PRIO_CEILING_MASK) == 0)
|
|
return EPERM;
|
|
/* FALLTHROUGH */
|
|
|
|
case PTHREAD_MUTEX_PP_NORMAL_NP:
|
|
case PTHREAD_MUTEX_PP_ADAPTIVE_NP:
|
|
/* Always reset the owner field. */
|
|
pp:
|
|
mutex->__data.__owner = 0;
|
|
|
|
if (decr)
|
|
/* One less user. */
|
|
--mutex->__data.__nusers;
|
|
|
|
/* Unlock. */
|
|
int newval, oldval;
|
|
do
|
|
{
|
|
oldval = mutex->__data.__lock;
|
|
newval = oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK;
|
|
}
|
|
while (atomic_compare_and_exchange_bool_rel (&mutex->__data.__lock,
|
|
newval, oldval));
|
|
|
|
if ((oldval & ~PTHREAD_MUTEX_PRIO_CEILING_MASK) > 1)
|
|
lll_futex_wake (&mutex->__data.__lock, 1,
|
|
PTHREAD_MUTEX_PSHARED (mutex));
|
|
|
|
int oldprio = newval >> PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
|
|
return __pthread_tpp_change_priority (oldprio, -1);
|
|
|
|
default:
|
|
/* Correct code cannot set any other type. */
|
|
return EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
int
|
|
__pthread_mutex_unlock (mutex)
|
|
pthread_mutex_t *mutex;
|
|
{
|
|
return __pthread_mutex_unlock_usercnt (mutex, 1);
|
|
}
|
|
strong_alias (__pthread_mutex_unlock, pthread_mutex_unlock)
|
|
strong_alias (__pthread_mutex_unlock, __pthread_mutex_unlock_internal)
|