1 /* $OpenBSD: kvm_getloadavg.c,v 1.9 2009/10/27 23:59:28 deraadt Exp $ */ 2 /* $NetBSD: kvm_getloadavg.c,v 1.2 1996/03/18 22:33:31 thorpej Exp $ */ 3 4 /*- 5 * Copyright (c) 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/param.h> 34 #include <sys/time.h> 35 #include <sys/resource.h> 36 #include <sys/proc.h> 37 #include <sys/sysctl.h> 38 39 #include <db.h> 40 #include <fcntl.h> 41 #include <limits.h> 42 #include <nlist.h> 43 #include <stdlib.h> 44 #include <kvm.h> 45 46 #include "kvm_private.h" 47 48 static struct nlist nl[] = { 49 { "_averunnable" }, 50 #define X_AVERUNNABLE 0 51 { "_fscale" }, 52 #define X_FSCALE 1 53 { "" }, 54 }; 55 56 /* 57 * kvm_getloadavg() -- Get system load averages, from live or dead kernels. 58 * 59 * Put `nelem' samples into `loadavg' array. 60 * Return number of samples retrieved, or -1 on error. 61 */ 62 int 63 kvm_getloadavg(kvm_t *kd, double loadavg[], int nelem) 64 { 65 struct loadavg loadinfo; 66 struct nlist *p; 67 int fscale, i; 68 69 if (ISALIVE(kd)) 70 return (getloadavg(loadavg, nelem)); 71 72 if (kvm_nlist(kd, nl) != 0) { 73 for (p = nl; p->n_type != 0; ++p) 74 ; 75 _kvm_err(kd, kd->program, 76 "%s: no such symbol", p->n_name); 77 return (-1); 78 } 79 80 if (KREAD(kd, nl[X_AVERUNNABLE].n_value, &loadinfo)) { 81 _kvm_err(kd, kd->program, "can't read averunnable"); 82 return (-1); 83 } 84 85 /* 86 * Old kernels have fscale separately; if not found assume 87 * running new format. 88 */ 89 if (!KREAD(kd, nl[X_FSCALE].n_value, &fscale)) 90 loadinfo.fscale = fscale; 91 92 nelem = MIN(nelem, sizeof(loadinfo.ldavg) / sizeof(fixpt_t)); 93 for (i = 0; i < nelem; i++) 94 loadavg[i] = (double) loadinfo.ldavg[i] / loadinfo.fscale; 95 return (nelem); 96 } 97