00001 /* 00002 * Copyright (C) 2005 Ondrej Palkovsky 00003 * All rights reserved. 00004 * 00005 * Redistribution and use in source and binary forms, with or without 00006 * modification, are permitted provided that the following conditions 00007 * are met: 00008 * 00009 * - Redistributions of source code must retain the above copyright 00010 * notice, this list of conditions and the following disclaimer. 00011 * - Redistributions in binary form must reproduce the above copyright 00012 * notice, this list of conditions and the following disclaimer in the 00013 * documentation and/or other materials provided with the distribution. 00014 * - The name of the author may not be used to endorse or promote products 00015 * derived from this software without specific prior written permission. 00016 * 00017 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 00018 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 00019 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 00020 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 00021 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 00022 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 00023 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 00024 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 00025 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 00026 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00027 */ 00028 00035 #ifndef __mips32_ATOMIC_H__ 00036 #define __mips32_ATOMIC_H__ 00037 00038 #define atomic_inc(x) ((void) atomic_add(x, 1)) 00039 #define atomic_dec(x) ((void) atomic_add(x, -1)) 00040 00041 #define atomic_postinc(x) (atomic_add(x, 1) - 1) 00042 #define atomic_postdec(x) (atomic_add(x, -1) + 1) 00043 00044 #define atomic_preinc(x) atomic_add(x, 1) 00045 #define atomic_predec(x) atomic_add(x, -1) 00046 00047 /* Atomic addition of immediate value. 00048 * 00049 * @param val Memory location to which will be the immediate value added. 00050 * @param i Signed immediate that will be added to *val. 00051 * 00052 * @return Value after addition. 00053 */ 00054 static inline long atomic_add(atomic_t *val, int i) 00055 { 00056 long tmp, v; 00057 00058 __asm__ volatile ( 00059 "1:\n" 00060 " ll %0, %1\n" 00061 " addiu %0, %0, %3\n" /* same as addi, but never traps on overflow */ 00062 " move %2, %0\n" 00063 " sc %0, %1\n" 00064 " beq %0, %4, 1b\n" /* if the atomic operation failed, try again */ 00065 /* nop */ /* nop is inserted automatically by compiler */ 00066 : "=r" (tmp), "=m" (val->count), "=r" (v) 00067 : "i" (i), "i" (0) 00068 ); 00069 00070 return v; 00071 } 00072 00073 #endif 00074