xref: /titanic_41/usr/src/uts/common/syscall/getloadavg.c (revision 1d4b38e0077763e7c9b20768eacb841957e787bc)
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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/systm.h>
31 #include <sys/errno.h>
32 #include <sys/loadavg.h>
33 #include <sys/zone.h>
34 #include <sys/pool_pset.h>
35 
36 /*
37  * Extract elements of the raw avenrun array from the kernel for the
38  * implementation of getloadavg(3c)
39  */
40 int
41 getloadavg(int *buf, int nelem)
42 {
43 	int *loadbuf = &avenrun[0];
44 	int loadavg[LOADAVG_NSTATS];
45 	int error;
46 
47 	if (nelem < 0)
48 		return (set_errno(EINVAL));
49 	if (nelem > LOADAVG_NSTATS)
50 		nelem = LOADAVG_NSTATS;
51 
52 	if (!INGLOBALZONE(curproc)) {
53 		mutex_enter(&cpu_lock);
54 		if (pool_pset_enabled()) {
55 			psetid_t psetid = zone_pset_get(curproc->p_zone);
56 
57 			error = cpupart_get_loadavg(psetid, &loadavg[0], nelem);
58 			ASSERT(error == 0);	/* pset isn't going anywhere */
59 			loadbuf = &loadavg[0];
60 		}
61 		mutex_exit(&cpu_lock);
62 	}
63 
64 	error = copyout(loadbuf, buf, nelem * sizeof (avenrun[0]));
65 	if (error)
66 		return (set_errno(EFAULT));
67 	return (nelem);
68 }
69