mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-27 04:41:02 +08:00
b22d701bb7
2003-04-04 Ulrich Drepper <drepper@redhat.com> * sysdeps/pthread/createthread.c (create_thread): Add some more comments explaining when to set multiple_threads and when not. * pthreadP.h: Define THREAD_ATOMIC_CMPXCHG_VAL and THREAD_ATOMIC_BIT_SET if not already defined. * sysdeps/i386/tls.h: Define THREAD_ATOMIC_CMPXCHG_VAL and THREAD_ATOMIC_BIT_SET: * sysdeps/x86_64/tls.h: Likewise. * cleanup_defer.c (_pthread_cleanup_push_defer): Rewrite to use THREAD_ATOMIC_CMPXCHG_VAL. (_pthread_cleanup_pop_restore): Likewise. * cancellation.c (__pthread_enable_asynccancel): Likewise. (__pthread_enable_asynccancel_2): Likewise. (__pthread_disable_asynccancel): Likewise. * libc-cancellation.c (__libc_enable_asynccancel): Likewise. (__libc_disable_asynccancel): Likewise. * init.c (sigcancel_handler): Likewise. * pthread_setcancelstate.c (__pthread_setcancelstate): Likewise. * pthread_setcanceltype.c (__pthread_setcanceltype): Likewise.
74 lines
2.3 KiB
C
74 lines
2.3 KiB
C
/* Copyright (C) 2002, 2003 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 <errno.h>
|
|
#include "pthreadP.h"
|
|
#include <atomic.h>
|
|
|
|
|
|
int
|
|
__pthread_setcancelstate (state, oldstate)
|
|
int state;
|
|
int *oldstate;
|
|
{
|
|
volatile struct pthread *self;
|
|
|
|
if (state < PTHREAD_CANCEL_ENABLE || state > PTHREAD_CANCEL_DISABLE)
|
|
return EINVAL;
|
|
|
|
self = THREAD_SELF;
|
|
|
|
int oldval = THREAD_GETMEM (self, cancelhandling);
|
|
while (1)
|
|
{
|
|
int newval = (state == PTHREAD_CANCEL_DISABLE
|
|
? oldval | CANCELSTATE_BITMASK
|
|
: oldval & ~CANCELSTATE_BITMASK);
|
|
|
|
/* Store the old value. */
|
|
if (oldstate != NULL)
|
|
*oldstate = ((oldval & CANCELSTATE_BITMASK)
|
|
? PTHREAD_CANCEL_DISABLE : PTHREAD_CANCEL_ENABLE);
|
|
|
|
/* Avoid doing unnecessary work. The atomic operation can
|
|
potentially be expensive if the memory has to be locked and
|
|
remote cache lines have to be invalidated. */
|
|
if (oldval == newval)
|
|
break;
|
|
|
|
/* Update the cancel handling word. This has to be done
|
|
atomically since other bits could be modified as well. */
|
|
int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
|
|
oldval);
|
|
if (__builtin_expect (curval == oldval, 1))
|
|
{
|
|
if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval))
|
|
__do_cancel ();
|
|
|
|
break;
|
|
}
|
|
|
|
/* Prepare for the next round. */
|
|
oldval = curval;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
strong_alias (__pthread_setcancelstate, pthread_setcancelstate)
|