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Diffstat (limited to 'linuxthreads/sysdeps/alpha/pspinlock.c')
| -rw-r--r-- | linuxthreads/sysdeps/alpha/pspinlock.c | 110 |
1 files changed, 0 insertions, 110 deletions
diff --git a/linuxthreads/sysdeps/alpha/pspinlock.c b/linuxthreads/sysdeps/alpha/pspinlock.c deleted file mode 100644 index 79b7836293..0000000000 --- a/linuxthreads/sysdeps/alpha/pspinlock.c +++ /dev/null @@ -1,110 +0,0 @@ -/* POSIX spinlock implementation. Alpha version. - Copyright (C) 2000 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - 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; see the file COPYING.LIB. If not, - write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. */ - -#include <errno.h> -#include <pthread.h> -#include "internals.h" - - -/* This implementation is similar to the one used in the Linux kernel. - But the kernel is byte instructions for the memory access. This is - faster but unusable here. The problem is that only 128 - threads/processes could use the spinlock at the same time. If (by - a design error in the program) a thread/process would hold the - spinlock for a time long enough to accumulate 128 waiting - processes, the next one will find a positive value in the spinlock - and assume it is unlocked. We cannot accept that. */ - -int -__pthread_spin_lock (pthread_spinlock_t *lock) -{ - unsigned int tmp; - asm volatile - ("1: ldl_l %0,%1\n" - " blbs %0,2f\n" - " or %0,1,%0\n" - " stl_c %0,%1\n" - " beq %0,2f\n" - " mb\n" - ".subsection 2\n" - "2: ldl %0,%1\n" - " blbs %0,2b\n" - " br 1b\n" - ".previous" - : "=r" (tmp), "=m" (lock) - : "m" (lock)); - return 0; -} -weak_alias (__pthread_spin_lock, pthread_spin_lock) - - -int -__pthread_spin_trylock (pthread_spinlock_t *lock) -{ - unsigned long int oldval; - unsigned long int temp; - - asm volatile - ("1: ldl_l %0,%1\n" - " and %0,%3,%2\n" - " bne %2,2f\n" - " xor %0,%3,%0\n" - " stl_c %0,%1\n" - " beq %0,3f\n" - " mb\n" - "2:\n" - ".subsection 2\n" - "3: br 1b\n" - ".previous" - : "=&r" (temp), "=m" (*lock), "=&r" (oldval) - : "Ir" (1UL), "m" (*lock)); - - return oldval == 0 ? 0 : EBUSY; -} -weak_alias (__pthread_spin_trylock, pthread_spin_trylock) - - -int -__pthread_spin_unlock (pthread_spinlock_t *lock) -{ - asm volatile ("mb"); - return *lock = 0; -} -weak_alias (__pthread_spin_unlock, pthread_spin_unlock) - - -int -__pthread_spin_init (pthread_spinlock_t *lock, int pshared) -{ - /* We can ignore the `pshared' parameter. Since we are busy-waiting - all processes which can access the memory location `lock' points - to can use the spinlock. */ - *lock = 0; - return 0; -} -weak_alias (__pthread_spin_init, pthread_spin_init) - - -int -__pthread_spin_destroy (pthread_spinlock_t *lock) -{ - /* Nothing to do. */ - return 0; -} -weak_alias (__pthread_spin_destroy, pthread_spin_destroy) |