xref: /titanic_41/usr/src/lib/libc/amd64/gen/lock.s (revision 734b6a94890be549309b21156f8ed6d4561cac51)
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27	.ident	"%Z%%M%	%I%	%E% SMI"
28
29	.file	"%M%"
30
31#include "SYS.h"
32
33/
34/ _lock_try(lp)
35/	- returns non-zero on success.
36/
37	ENTRY(_lock_try)
38	movl	$1,%eax
39	xchgb	%al, (%rdi)
40	xorb	$1, %al
41	ret
42	SET_SIZE(_lock_try)
43
44/
45/ _lock_clear(lp)
46/	- clear lock and force it to appear unlocked in memory.
47/
48	ENTRY(_lock_clear)
49	movb	$0, (%rdi)
50	ret
51	SET_SIZE(_lock_clear)
52