/* POSIX spinlock implementation. AM33 version. Copyright 2001-2014 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 Library General Public License as published by the Free Software Foundation; either version 2 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 Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library. If not, see . */ #include #include #include "internals.h" int __pthread_spin_lock (pthread_spinlock_t *lock) { __asm__ __volatile__("1: bset %1, (%0); beq 1b" : : "a" (lock), "d" (1) : "memory"); return 0; } weak_alias (__pthread_spin_lock, pthread_spin_lock) int __pthread_spin_trylock (pthread_spinlock_t *lock) { int oldval = 1; __asm__ __volatile__ ("bset %0, (%1); beq 1f; clr %0; 1:" : "+d" (oldval) : "a" (lock) : "memory"); return oldval ? EBUSY : 0; } weak_alias (__pthread_spin_trylock, pthread_spin_trylock) int __pthread_spin_unlock (pthread_spinlock_t *lock) { *lock = 0; return 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)