freebsd-dev/lib/libkse/arch/amd64/include/atomic_ops.h
Daniel Eischen eb63e604ea WARNS=3'ify.
2007-11-30 17:20:29 +00:00

58 lines
2.0 KiB
C

/*-
* Copyright (c) 2001 Daniel Eischen <deischen@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Neither the name of the author nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _ATOMIC_OPS_H_
#define _ATOMIC_OPS_H_
/*
* Atomic swap:
* Atomic (tmp = *dst, *dst = val), then *res = tmp
*
* void atomic_swap64(intptr_t *dst, intptr_t val, intptr_t *res);
*/
static inline void
atomic_swap64(volatile intptr_t *dst, intptr_t val, intptr_t *res)
{
__asm __volatile(
"xchgq %2, %1; movq %2, %0"
: "=m" (*res) : "m" (*dst), "r" (val) : "memory");
}
static inline void
atomic_swap_int(volatile int *dst, int val, int *res)
{
__asm __volatile(
"xchgl %2, %1; movl %2, %0"
: "=m" (*res) : "m" (*dst), "r" (val) : "memory");
}
#define atomic_swap_ptr(d, v, r) \
atomic_swap64((volatile intptr_t *)(d), (intptr_t)(v), (intptr_t *)(r))
#endif