mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 16:50:07 +00:00
9a7178d611
2003-05-01 Ulrich Drepper <drepper@redhat.com> * sysdeps/i386/tls.h: Define THREAD_ID. * sysdeps/ia64/tls.h: Likewise. * sysdeps/powerpc/tls.h: Likewise. * sysdeps/s390/tls.h: Likewise. * sysdeps/sh/tls.h: Likewise. * sysdeps/x86_64/tls.h: Likewise. * pthread_mutex_lock.c: Use THREAD_ID instead of THREAD_SELF to record ownership. * pthread_mutex_timedlock.c: Likewise. * pthread_mutex_trylock.c: Likewise. * pthread_mutex_unlock.c: Likewise. * pthread_rwlock_trywrlock.c: Likewise. * sysdeps/pthread/pthread_rwlocklock_rdlock.c: Likewise. * sysdeps/pthread/pthread_rwlock_timedrdlock.c: Likewise. * sysdeps/pthread/pthread_rwlock_timedwrlock.c: Likewise. * sysdeps/pthread/pthread_rwlock_wrlock.c: Likewise. * sysdeps/pthread/createthread.c (create_thread): Use CLONE_SYSVSEM flag.
89 lines
2.6 KiB
C
89 lines
2.6 KiB
C
/* Copyright (C) 2003 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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#include <errno.h>
|
|
#include <sysdep.h>
|
|
#include <lowlevellock.h>
|
|
#include <pthread.h>
|
|
#include <pthreadP.h>
|
|
|
|
|
|
/* Acquire write lock for RWLOCK. */
|
|
int
|
|
__pthread_rwlock_wrlock (rwlock)
|
|
pthread_rwlock_t *rwlock;
|
|
{
|
|
int result = 0;
|
|
|
|
/* Make sure we are along. */
|
|
lll_mutex_lock (rwlock->__data.__lock);
|
|
|
|
while (1)
|
|
{
|
|
/* Get the rwlock if there is no writer and no reader. */
|
|
if (rwlock->__data.__writer == 0 && rwlock->__data.__nr_readers == 0)
|
|
{
|
|
/* Mark self as writer. */
|
|
rwlock->__data.__writer = (pthread_t) THREAD_ID;
|
|
break;
|
|
}
|
|
|
|
/* Make sure we are not holding the rwlock as a writer. This is
|
|
a deadlock situation we recognize and report. */
|
|
if (rwlock->__data.__writer != 0
|
|
&& __builtin_expect (rwlock->__data.__writer
|
|
== (pthread_t) THREAD_ID, 0))
|
|
{
|
|
result = EDEADLK;
|
|
break;
|
|
}
|
|
|
|
/* Remember that we are a writer. */
|
|
if (++rwlock->__data.__nr_writers_queued == 0)
|
|
{
|
|
/* Overflow on number of queued writers. */
|
|
--rwlock->__data.__nr_writers_queued;
|
|
result = EAGAIN;
|
|
break;
|
|
}
|
|
|
|
int waitval = rwlock->__data.__writer_wakeup;
|
|
|
|
/* Free the lock. */
|
|
lll_mutex_unlock (rwlock->__data.__lock);
|
|
|
|
/* Wait for the writer or reader(s) to finish. */
|
|
lll_futex_wait (&rwlock->__data.__writer_wakeup, waitval);
|
|
|
|
/* Get the lock. */
|
|
lll_mutex_lock (rwlock->__data.__lock);
|
|
|
|
/* To start over again, remove the thread from the writer list. */
|
|
--rwlock->__data.__nr_writers_queued;
|
|
}
|
|
|
|
/* We are done, free the lock. */
|
|
lll_mutex_unlock (rwlock->__data.__lock);
|
|
|
|
return result;
|
|
}
|
|
|
|
weak_alias (__pthread_rwlock_wrlock, pthread_rwlock_wrlock)
|
|
strong_alias (__pthread_rwlock_wrlock, __pthread_rwlock_wrlock_internal)
|