/* Low-level functions for atomic operations. Sparc32 version. Copyright (C) 1999 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; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #ifndef _ATOMICITY_H #define _ATOMICITY_H 1 #include <inttypes.h> static int __attribute_used__ exchange_and_add (volatile uint32_t *mem, int val) { static unsigned char lock; int result, tmp; __asm__ __volatile__("1: ldstub [%1], %0\n\t" " cmp %0, 0\n\t" " bne 1b\n\t" " nop" : "=&r" (tmp) : "r" (&lock) : "memory"); result = *mem; *mem += val; __asm__ __volatile__("stb %%g0, [%0]" : /* no outputs */ : "r" (&lock) : "memory"); return result; } static void __attribute_used__ atomic_add (volatile uint32_t *mem, int val) { static unsigned char lock; int tmp; __asm__ __volatile__("1: ldstub [%1], %0\n\t" " cmp %0, 0\n\t" " bne 1b\n\t" " nop" : "=&r" (tmp) : "r" (&lock) : "memory"); *mem += val; __asm__ __volatile__("stb %%g0, [%0]" : /* no outputs */ : "r" (&lock) : "memory"); } static int __attribute_used__ compare_and_swap (volatile long int *p, long int oldval, long int newval) { static unsigned char lock; int ret, tmp; __asm__ __volatile__("1: ldstub [%1], %0\n\t" " cmp %0, 0\n\t" " bne 1b\n\t" " nop" : "=&r" (tmp) : "r" (&lock) : "memory"); if (*p != oldval) ret = 0; else { *p = newval; ret = 1; } __asm__ __volatile__("stb %%g0, [%0]" : /* no outputs */ : "r" (&lock) : "memory"); return ret; } #endif /* atomicity.h */