atomic_ops.h revision 137283
1129206Scognet/*- 2129206Scognet * Copyright (c) 2001 Daniel Eischen <deischen@FreeBSD.org> 3129206Scognet * All rights reserved. 4129206Scognet * 5129206Scognet * Redistribution and use in source and binary forms, with or without 6129206Scognet * modification, are permitted provided that the following conditions 7129206Scognet * are met: 8129206Scognet * 1. Redistributions of source code must retain the above copyright 9129206Scognet * notice, this list of conditions and the following disclaimer. 10129206Scognet * 2. Neither the name of the author nor the names of its contributors 11129206Scognet * may be used to endorse or promote products derived from this software 12129206Scognet * without specific prior written permission. 13129206Scognet * 14129206Scognet * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15129206Scognet * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16129206Scognet * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17129206Scognet * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18129206Scognet * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19129206Scognet * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20129206Scognet * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21129206Scognet * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22129206Scognet * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23129206Scognet * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24129206Scognet * SUCH DAMAGE. 25129206Scognet * 26129206Scognet * $FreeBSD: head/lib/libkse/arch/arm/include/atomic_ops.h 137283 2004-11-05 23:49:21Z cognet $ 27129206Scognet */ 28129206Scognet 29129206Scognet#ifndef _ATOMIC_OPS_H_ 30129206Scognet#define _ATOMIC_OPS_H_ 31129206Scognet 32137283Scognet#include <machine/atomic.h> 33137283Scognet#include "thr_private.h" 34137283Scognet 35129206Scognet/* 36129206Scognet * Atomic swap: 37129206Scognet * Atomic (tmp = *dst, *dst = val), then *res = tmp 38129206Scognet * 39129206Scognet * void atomic_swap32(intptr_t *dst, intptr_t val, intptr_t *res); 40129206Scognet */ 41129206Scognetstatic inline void 42129206Scognetatomic_swap32(intptr_t *dst, intptr_t val, intptr_t *res) 43129206Scognet{ 44137283Scognet *res = __swp(val, dst); 45129206Scognet} 46129206Scognet 47129206Scognet#define atomic_swap_ptr(d, v, r) \ 48129206Scognet atomic_swap32((intptr_t *)d, (intptr_t)v, (intptr_t *)r) 49129206Scognet 50129206Scognet#define atomic_swap_int(d, v, r) \ 51129206Scognet atomic_swap32((intptr_t *)d, (intptr_t)v, (intptr_t *)r) 52129206Scognet#endif 53137283Scognet 54137283Scognetstatic inline u_int32_t 55137283Scognetatomic_cmpset_32(volatile u_int32_t *p, u_int32_t cmpval, u_int32_t newval) 56137283Scognet{ 57137283Scognet kse_critical_t crit = _kse_critical_enter(); 58137283Scognet int ret; 59137283Scognet 60137283Scognet if (*p == cmpval) { 61137283Scognet *p = newval; 62137283Scognet ret = 1; 63137283Scognet } else 64137283Scognet ret = 0; 65137283Scognet _kse_critical_leave(crit); 66137283Scognet return (ret); 67137283Scognet} 68137283Scognet 69