diff options
Diffstat (limited to 'nptl/sysdeps/unix')
-rw-r--r-- | nptl/sysdeps/unix/sysv/linux/powerpc/pthread_once.c | 110 |
1 files changed, 0 insertions, 110 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/powerpc/pthread_once.c b/nptl/sysdeps/unix/sysv/linux/powerpc/pthread_once.c deleted file mode 100644 index e925299b2a..0000000000 --- a/nptl/sysdeps/unix/sysv/linux/powerpc/pthread_once.c +++ /dev/null @@ -1,110 +0,0 @@ -/* Copyright (C) 2003-2014 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Paul Mackerras <paulus@au.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, see - <http://www.gnu.org/licenses/>. */ - -#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; - - __asm __volatile (__lll_rel_instr); - *once_control = 0; - lll_futex_wake (once_control, INT_MAX, LLL_PRIVATE); -} - - -int -__pthread_once (pthread_once_t *once_control, void (*init_routine) (void)) -{ - for (;;) - { - int oldval; - int newval; - int tmp; - - /* Pseudo code: - newval = __fork_generation | 1; - oldval = *once_control; - if ((oldval & 2) == 0) - *once_control = newval; - Do this atomically with an acquire barrier. - */ - newval = __fork_generation | 1; - __asm __volatile ("1: lwarx %0,0,%3" MUTEX_HINT_ACQ "\n" - " andi. %1,%0,2\n" - " bne 2f\n" - " stwcx. %4,0,%3\n" - " bne 1b\n" - "2: " __lll_acq_instr - : "=&r" (oldval), "=&r" (tmp), "=m" (*once_control) - : "r" (once_control), "r" (newval), "m" (*once_control) - : "cr0"); - - /* Check if the initializer has already been done. */ - if ((oldval & 2) != 0) - return 0; - - /* Check if another thread already runs the initializer. */ - if ((oldval & 1) == 0) - break; - - /* Check whether the initializer execution was interrupted by a fork. */ - if (oldval != newval) - break; - - /* Same generation, some other thread was faster. Wait. */ - lll_futex_wait (once_control, oldval, LLL_PRIVATE); - } - - - /* 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 to take the bottom 2 bits from 01 to 10. - A release barrier is needed to ensure memory written by init_routine - is seen in other threads before *once_control changes. */ - int tmp; - __asm __volatile (__lll_rel_instr "\n" - "1: lwarx %0,0,%2" MUTEX_HINT_REL "\n" - " addi %0,%0,1\n" - " stwcx. %0,0,%2\n" - " bne- 1b" - : "=&b" (tmp), "=m" (*once_control) - : "r" (once_control), "m" (*once_control) - : "cr0"); - - /* Wake up all other threads. */ - lll_futex_wake (once_control, INT_MAX, LLL_PRIVATE); - - return 0; -} -weak_alias (__pthread_once, pthread_once) -hidden_def (__pthread_once) |