1 /* $OpenBSD: kvm_getloadavg.c,v 1.2 1996/05/05 14:57:12 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. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)kvm_getloadavg.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 static char *rcsid = "$OpenBSD: kvm_getloadavg.c,v 1.2 1996/05/05 14:57:12 deraadt Exp $"; 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #include <sys/param.h> 46 #include <sys/time.h> 47 #include <sys/resource.h> 48 #include <sys/proc.h> 49 #include <sys/sysctl.h> 50 #include <vm/vm_param.h> 51 52 #include <db.h> 53 #include <fcntl.h> 54 #include <limits.h> 55 #include <nlist.h> 56 #include <kvm.h> 57 58 #include "kvm_private.h" 59 60 static struct nlist nl[] = { 61 { "_averunnable" }, 62 #define X_AVERUNNABLE 0 63 { "_fscale" }, 64 #define X_FSCALE 1 65 { "" }, 66 }; 67 68 /* 69 * kvm_getloadavg() -- Get system load averages, from live or dead kernels. 70 * 71 * Put `nelem' samples into `loadavg' array. 72 * Return number of samples retrieved, or -1 on error. 73 */ 74 int 75 kvm_getloadavg(kd, loadavg, nelem) 76 kvm_t *kd; 77 double loadavg[]; 78 int nelem; 79 { 80 struct loadavg loadinfo; 81 struct nlist *p; 82 int fscale, i; 83 84 if (ISALIVE(kd)) 85 return (getloadavg(loadavg, nelem)); 86 87 if (kvm_nlist(kd, nl) != 0) { 88 for (p = nl; p->n_type != 0; ++p); 89 _kvm_err(kd, kd->program, 90 "%s: no such symbol", p->n_name); 91 return (-1); 92 } 93 94 #define KREAD(kd, addr, obj) \ 95 (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) 96 if (KREAD(kd, nl[X_AVERUNNABLE].n_value, &loadinfo)) { 97 _kvm_err(kd, kd->program, "can't read averunnable"); 98 return (-1); 99 } 100 101 /* 102 * Old kernels have fscale separately; if not found assume 103 * running new format. 104 */ 105 if (!KREAD(kd, nl[X_FSCALE].n_value, &fscale)) 106 loadinfo.fscale = fscale; 107 108 nelem = MIN(nelem, sizeof(loadinfo.ldavg) / sizeof(fixpt_t)); 109 for (i = 0; i < nelem; i++) 110 loadavg[i] = (double) loadinfo.ldavg[i] / loadinfo.fscale; 111 return (nelem); 112 } 113