xref: /titanic_52/usr/src/lib/libc/sparc/gen/lock.s (revision d92a527c473246e5c750ae6c33ecd2f242a5bf1f)
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 (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26	.file	"lock.s"
27
28#include <sys/asm_linkage.h>
29
30/*
31 * lock_try(lp)
32 *	- returns non-zero on success.
33 */
34	ENTRY(_lock_try)
35	ldstub	[%o0], %o1		! try to set lock, get value in %o1
36	membar	#LoadLoad
37	retl
38	  xor	%o1, 0xff, %o0		! delay - return non-zero if success
39	SET_SIZE(_lock_try)
40
41/*
42 * lock_clear(lp)
43 *	- clear lock.
44 */
45	ENTRY(_lock_clear)
46	membar	#LoadStore|#StoreStore
47	retl
48	  clrb	[%o0]
49	SET_SIZE(_lock_clear)
50