1 /* $NetBSD: kvm_getloadavg.c,v 1.6 2000/06/26 17:36:56 mrg Exp $ */ 2 3 /*- 4 * Copyright (c) 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[] = "@(#)kvm_getloadavg.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: kvm_getloadavg.c,v 1.6 2000/06/26 17:36:56 mrg 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 <uvm/uvm_param.h> 51 52 #include <db.h> 53 #include <fcntl.h> 54 #include <limits.h> 55 #include <nlist.h> 56 #include <kvm.h> 57 #include <stdlib.h> 58 59 #include "kvm_private.h" 60 61 static struct nlist nl[] = { 62 { "_averunnable" }, 63 #define X_AVERUNNABLE 0 64 { "_fscale" }, 65 #define X_FSCALE 1 66 { "" }, 67 }; 68 69 /* 70 * kvm_getloadavg() -- Get system load averages, from live or dead kernels. 71 * 72 * Put `nelem' samples into `loadavg' array. 73 * Return number of samples retrieved, or -1 on error. 74 */ 75 int 76 kvm_getloadavg(kd, loadavg, nelem) 77 kvm_t *kd; 78 double loadavg[]; 79 int nelem; 80 { 81 struct loadavg loadinfo; 82 struct nlist *p; 83 int fscale, i; 84 85 if (ISALIVE(kd)) 86 return (getloadavg(loadavg, nelem)); 87 88 if (kvm_nlist(kd, nl) != 0) { 89 for (p = nl; p->n_type != 0; ++p); 90 _kvm_err(kd, kd->program, 91 "%s: no such symbol", p->n_name); 92 return (-1); 93 } 94 95 #define KREAD(kd, addr, obj) \ 96 (kvm_read(kd, addr, (void *)(obj), sizeof(*obj)) != sizeof(*obj)) 97 if (KREAD(kd, nl[X_AVERUNNABLE].n_value, &loadinfo)) { 98 _kvm_err(kd, kd->program, "can't read averunnable"); 99 return (-1); 100 } 101 102 /* 103 * Old kernels have fscale separately; if not found assume 104 * running new format. 105 */ 106 if (!KREAD(kd, nl[X_FSCALE].n_value, &fscale)) 107 loadinfo.fscale = fscale; 108 109 nelem = MIN(nelem, sizeof(loadinfo.ldavg) / sizeof(fixpt_t)); 110 for (i = 0; i < nelem; i++) 111 loadavg[i] = (double) loadinfo.ldavg[i] / loadinfo.fscale; 112 return (nelem); 113 } 114