glibc/sysdeps/unix/sysv/linux/hppa/nptl/pthread_once.c
Carlos O'Donell b599860dc8 2007-07-28 Carlos O'Donell <carlos@systemhalted.org>
* sysdeps/unix/sysv/linux/hppa/nptl/internaltypes.h: Remove.
	* sysdeps/unix/sysv/linux/hppa/nptl/bits/pthreadtypes.h
	(pthread_rwlock_t): Split __flags into __pad2, __pad1, __shared,
	and __flags. Update comments. Update copyright.
	* sysdeps/hppa/nptl/tls.h: Define THREAD_GSCOPE_FLAG_UNUSED,
	THREAD_GSCOPE_FLAG_USED, THREAD_GSOPE_FLAG_WAIT,
	THREAD_GSCOPE_RSEET_FLAG, THREAD_GSCOPE_SET_FLAG, THREAD_GSCOPE_WAIT.
	Update copyright.
	* sysdeps/unix/sysv/linux/hppa/nptl/lowlevellock.c: Update copyright.
	(__lll_lock_wait): Call lll_futex_wait with LLL_SHARED.
	(__lll_timedlock_wait): Call lll_futex_timed_wait with LLL_SHARED.
	(lll_unlock_Wake_cb): Use lll_private_futex_wake.
	(___lll_timedwait_tid): Call lll_futex_timed_wait with LLL_SAHRED.
	* sysdeps/unix/sysv/linux/hppa/nptl/lowlevellock.h: Define
	FUTEX_PRIVATE_FLAG, LLL_PRIVATE, LLL_SHARED, lll_private_futex_wait,
	lll_private_futex_timed_wait, lll_private_Futex_wake. Add private
	argument to lll_futex_wait, lll_futex_timed_wait, lll_futex_wake,
	lll_futex_wake_unlock.
	* sysdeps/unix/sysv/linux/hppa/nptl/pthread_once.c: Update copyright.
	(clear_once_control): Use lll_private_futex_wake.
	(__pthread_once): Use lll_private_futex_wait, and
	lll_private_futex_wake.

2007-07-28  Randolph Chung  <tausq@debian.org>

	* sysdeps/hppa/nptl/tls.h (DB_THREAD_SELF): Fix definition.
2007-07-28 21:26:44 +00:00

95 lines
2.6 KiB
C

/* Copyright (C) 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.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 "pthreadP.h"
#include <lowlevellock.h>
unsigned long int __fork_generation attribute_hidden;
static void
clear_once_control (void *arg)
{
pthread_once_t *once_control = (pthread_once_t *) arg;
*once_control = 0;
lll_private_futex_wake (once_control, INT_MAX);
}
int
__pthread_once (once_control, init_routine)
pthread_once_t *once_control;
void (*init_routine) (void);
{
while (1)
{
int oldval, val, newval;
val = *once_control;
do
{
/* Check if the initialized has already been done. */
if ((val & 2) != 0)
return 0;
oldval = val;
newval = (oldval & 3) | __fork_generation | 1;
val = atomic_compare_and_exchange_val_acq (once_control, newval,
oldval);
}
while (__builtin_expect (val != oldval, 0));
/* Check if another thread already runs the initializer. */
if ((oldval & 1) != 0)
{
/* Check whether the initializer execution was interrupted
by a fork. */
if (((oldval ^ newval) & -4) == 0)
{
/* Same generation, some other thread was faster. Wait. */
lll_private_futex_wait (once_control, newval);
continue;
}
}
/* This thread is the first here. Do the initialization.
Register a cleanup handler so that in case the thread gets
interrupted the initialization can be restarted. */
pthread_cleanup_push (clear_once_control, once_control);
init_routine ();
pthread_cleanup_pop (0);
/* Add one to *once_control. */
atomic_increment (once_control);
/* Wake up all other threads. */
lll_private_futex_wake (once_control, INT_MAX);
break;
}
return 0;
}
weak_alias (__pthread_once, pthread_once)
strong_alias (__pthread_once, __pthread_once_internal)