xref: /titanic_50/usr/src/uts/i86pc/os/mp_call.c (revision 6bbe05905a1c10a2703f95fb4912eb14b87f6670)
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 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <sys/types.h>
28 #include <sys/param.h>
29 #include <sys/thread.h>
30 #include <sys/cpuvar.h>
31 #include <sys/machsystm.h>
32 #include <sys/systm.h>
33 #include <sys/promif.h>
34 #include <sys/xc_levels.h>
35 
36 /*
37  * Interrupt another CPU.
38  * 	This is useful to make the other CPU go through a trap so that
39  *	it recognizes an address space trap (AST) for preempting a thread.
40  *
41  *	It is possible to be preempted here and be resumed on the CPU
42  *	being poked, so it isn't an error to poke the current CPU.
43  *	We could check this and still get preempted after the check, so
44  *	we don't bother.
45  */
46 void
47 poke_cpu(int cpun)
48 {
49 	if (panicstr)
50 		return;
51 	/*
52 	 * We don't need to receive an ACK from the CPU being poked,
53 	 * so just send out a directed interrupt.
54 	 */
55 	send_dirint(cpun, XC_CPUPOKE_PIL);
56 }
57