1 /*- 2 * Copyright (c) 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char sccsid[] = "@(#)kvm_getloadavg.c 8.1 (Berkeley) 6/4/93"; 36 #endif 37 #endif /* LIBC_SCCS and not lint */ 38 39 #include <sys/param.h> 40 #include <sys/time.h> 41 #include <sys/resource.h> 42 43 #include <stdlib.h> 44 #include <limits.h> 45 #include <nlist.h> 46 #include <kvm.h> 47 48 #include "kvm_private.h" 49 50 static struct nlist nl[] = { 51 { "_averunnable" }, 52 #define X_AVERUNNABLE 0 53 { "_fscale" }, 54 #define X_FSCALE 1 55 { "" }, 56 }; 57 58 /* 59 * kvm_getloadavg() -- Get system load averages, from live or dead kernels. 60 * 61 * Put `nelem' samples into `loadavg' array. 62 * Return number of samples retrieved, or -1 on error. 63 */ 64 int 65 kvm_getloadavg(kd, loadavg, nelem) 66 kvm_t *kd; 67 double loadavg[]; 68 int nelem; 69 { 70 struct loadavg loadinfo; 71 struct nlist *p; 72 int fscale, i; 73 74 if (ISALIVE(kd)) 75 return (getloadavg(loadavg, nelem)); 76 77 if (kvm_nlist(kd, nl) != 0) { 78 for (p = nl; p->n_type != 0; ++p); 79 _kvm_err(kd, kd->program, 80 "%s: no such symbol", p->n_name); 81 return (-1); 82 } 83 84 #define KREAD(kd, addr, obj) \ 85 (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) 86 if (KREAD(kd, nl[X_AVERUNNABLE].n_value, &loadinfo)) { 87 _kvm_err(kd, kd->program, "can't read averunnable"); 88 return (-1); 89 } 90 91 /* 92 * Old kernels have fscale separately; if not found assume 93 * running new format. 94 */ 95 if (!KREAD(kd, nl[X_FSCALE].n_value, &fscale)) 96 loadinfo.fscale = fscale; 97 98 nelem = MIN(nelem, sizeof(loadinfo.ldavg) / sizeof(fixpt_t)); 99 for (i = 0; i < nelem; i++) 100 loadavg[i] = (double) loadinfo.ldavg[i] / loadinfo.fscale; 101 return (nelem); 102 } 103