kernel/syscall/getloadavg.c

   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  * Copyright 2011 Joyent, Inc.  All rights reserved.
  26  */
  27
  28 #include <sys/types.h>
  29 #include <sys/systm.h>
  30 #include <sys/errno.h>
  31 #include <sys/loadavg.h>
  32 #include <sys/zone.h>
  33 #include <sys/pool_pset.h>
  34
  35 /*
  36  * Extract elements of the raw avenrun array from the kernel for the
  37  * implementation of getloadavg(3c)
  38  */
  39 int
  40 getloadavg(int *buf, int nelem)
  41 {
  42         int *loadbuf = &avenrun[0];
  43         int error;
  44
  45         if (nelem < 0)
  46                 return (set_errno(EINVAL));
  47         if (nelem > LOADAVG_NSTATS)
  48                 nelem = LOADAVG_NSTATS;
  49
  50         if (!INGLOBALZONE(curproc)) {
  51                 loadbuf = &curproc->p_zone->zone_avenrun[0];
  52         }
  53
  54         error = copyout(loadbuf, buf, nelem * sizeof (avenrun[0]));
  55         if (error)
  56                 return (set_errno(EFAULT));
  57         return (nelem);
  58 }