1 /* $NetBSD: getloadavg.c,v 1.12 2002/11/11 16:58:42 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)getloadavg.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: getloadavg.c,v 1.12 2002/11/11 16:58:42 thorpej Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #include "namespace.h" 46 #include <sys/param.h> 47 #include <sys/time.h> 48 #include <sys/resource.h> 49 #include <sys/sysctl.h> 50 #include <uvm/uvm_param.h> 51 52 #include <assert.h> 53 #include <errno.h> 54 #include <stdlib.h> 55 56 #ifdef __weak_alias 57 __weak_alias(getloadavg,_getloadavg) 58 #endif 59 60 /* 61 * getloadavg() -- Get system load averages. 62 * 63 * Put `nelem' samples into `loadavg' array. 64 * Return number of samples retrieved, or -1 on error. 65 */ 66 int 67 getloadavg(loadavg, nelem) 68 double loadavg[]; 69 int nelem; 70 { 71 struct loadavg loadinfo; 72 int i, mib[2]; 73 size_t size; 74 75 _DIAGASSERT(loadavg != NULL); 76 _DIAGASSERT(nelem >= 0); 77 78 mib[0] = CTL_VM; 79 mib[1] = VM_LOADAVG; 80 size = sizeof(loadinfo); 81 if (sysctl(mib, 2, &loadinfo, &size, NULL, 0) < 0) 82 return (-1); 83 84 nelem = MIN((size_t) nelem, sizeof(loadinfo.ldavg) / sizeof(fixpt_t)); 85 for (i = 0; i < nelem; i++) 86 loadavg[i] = (double) loadinfo.ldavg[i] / loadinfo.fscale; 87 return (nelem); 88 } 89