1*5d9d9091SRichard Lowe/*
2*5d9d9091SRichard Lowe * CDDL HEADER START
3*5d9d9091SRichard Lowe *
4*5d9d9091SRichard Lowe * The contents of this file are subject to the terms of the
5*5d9d9091SRichard Lowe * Common Development and Distribution License (the "License").
6*5d9d9091SRichard Lowe * You may not use this file except in compliance with the License.
7*5d9d9091SRichard Lowe *
8*5d9d9091SRichard Lowe * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9*5d9d9091SRichard Lowe * or http://www.opensolaris.org/os/licensing.
10*5d9d9091SRichard Lowe * See the License for the specific language governing permissions
11*5d9d9091SRichard Lowe * and limitations under the License.
12*5d9d9091SRichard Lowe *
13*5d9d9091SRichard Lowe * When distributing Covered Code, include this CDDL HEADER in each
14*5d9d9091SRichard Lowe * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15*5d9d9091SRichard Lowe * If applicable, add the following below this CDDL HEADER, with the
16*5d9d9091SRichard Lowe * fields enclosed by brackets "[]" replaced with your own identifying
17*5d9d9091SRichard Lowe * information: Portions Copyright [yyyy] [name of copyright owner]
18*5d9d9091SRichard Lowe *
19*5d9d9091SRichard Lowe * CDDL HEADER END
20*5d9d9091SRichard Lowe */
21*5d9d9091SRichard Lowe/*
22*5d9d9091SRichard Lowe * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
23*5d9d9091SRichard Lowe */
24*5d9d9091SRichard Lowe
25*5d9d9091SRichard Lowe	.file	"smt_pause.s"
26*5d9d9091SRichard Lowe
27*5d9d9091SRichard Lowe#include <sys/asm_linkage.h>
28*5d9d9091SRichard Lowe#include <../assym.h>
29*5d9d9091SRichard Lowe
30*5d9d9091SRichard Lowe/*
31*5d9d9091SRichard Lowe * void smt_pause(void)
32*5d9d9091SRichard Lowe *
33*5d9d9091SRichard Lowe * Do nothing efficiently.
34*5d9d9091SRichard Lowe */
35*5d9d9091SRichard Lowe
36*5d9d9091SRichard Lowe#ifdef lint
37*5d9d9091SRichard Lowevoid
38*5d9d9091SRichard Lowesmt_pause(void)
39*5d9d9091SRichard Lowe{
40*5d9d9091SRichard Lowe}
41*5d9d9091SRichard Lowe#else
42*5d9d9091SRichard Lowe#define	BANKS	(4 * 64)
43*5d9d9091SRichard Lowe	ENTRY(smt_pause)
44*5d9d9091SRichard Lowe	save %sp, -SA(MINFRAME+BANKS), %sp
45*5d9d9091SRichard Lowe	ld      [%g7 + UL_LWPID], %i3   ! curthread->ul_lwpid
46*5d9d9091SRichard Lowe	add	%fp, STACK_BIAS-BANKS, %i0
47*5d9d9091SRichard Lowe	and     %i3, 0x3, %i2           ! save last 2 bits
48*5d9d9091SRichard Lowe	sllx    %i2, 0x6, %i1           ! pick a slot
49*5d9d9091SRichard Lowe	add     %i1, %i0, %o0
50*5d9d9091SRichard Lowe	casx    [%o0], %g0, %g0
51*5d9d9091SRichard Lowe	casx    [%o0], %g0, %g0
52*5d9d9091SRichard Lowe	ret
53*5d9d9091SRichard Lowe	restore
54*5d9d9091SRichard Lowe	SET_SIZE(smt_pause)
55*5d9d9091SRichard Lowe#endif
56