From 9063793868eac8f17d8cbe80134b8e498b749098 Mon Sep 17 00:00:00 2001 From: Simon Schubert Date: Thu, 27 Jul 2006 00:43:35 +0000 Subject: [PATCH] Add amd64 atomic_lock implementation Obtained-from: FreeBSD --- lib/libc_r/arch/amd64/_atomic_lock.S | 39 ++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 lib/libc_r/arch/amd64/_atomic_lock.S diff --git a/lib/libc_r/arch/amd64/_atomic_lock.S b/lib/libc_r/arch/amd64/_atomic_lock.S new file mode 100644 index 0000000000..b5248c532a --- /dev/null +++ b/lib/libc_r/arch/amd64/_atomic_lock.S @@ -0,0 +1,39 @@ +/* + * Copyright (c) 1995-1998 John Birrell . + * All rights reserved. + * copyright Douglas Santry 1996 + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the above copyright is retained + * in the source form. + * + * THIS SOFTWARE IS PROVIDED BY Douglas Santry 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 Douglas Santry 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: src/lib/libc_r/arch/i386/_atomic_lock.S,v 1.3 1999/08/28 00:03:01 peter Exp $ + * $DragonFly: src/lib/libc_r/arch/amd64/_atomic_lock.S,v 1.1 2006/07/27 00:43:35 corecode Exp $ + */ + +#include "DEFS.h" + +/* + * Atomicly lock a location with an identifier provided the location + * is not currently locked. + * + * long _atomic_lock(long *); + * rax will contain the return value (zero if lock obtained). + */ +ENTRY(_atomic_lock) + movq $1,%rax + xchgq %rax,(%rdi) + ret + -- 2.28.0