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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)kvm_getloadavg.c 8.1 (Berkeley) 6/4/93"; 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include <sys/param.h> 39 #include <sys/time.h> 40 #include <sys/resource.h> 41 #include <sys/proc.h> 42 #include <sys/sysctl.h> 43 #include <vm/vm_param.h> 44 45 #include <stdlib.h> 46 #include <db.h> 47 #include <fcntl.h> 48 #include <limits.h> 49 #include <nlist.h> 50 #include <kvm.h> 51 52 #include "kvm_private.h" 53 54 static struct nlist nl[] = { 55 { "_averunnable" }, 56 #define X_AVERUNNABLE 0 57 { "_fscale" }, 58 #define X_FSCALE 1 59 { "" }, 60 }; 61 62 /* 63 * kvm_getloadavg() -- Get system load averages, from live or dead kernels. 64 * 65 * Put `nelem' samples into `loadavg' array. 66 * Return number of samples retrieved, or -1 on error. 67 */ 68 int 69 kvm_getloadavg(kd, loadavg, nelem) 70 kvm_t *kd; 71 double loadavg[]; 72 int nelem; 73 { 74 struct loadavg loadinfo; 75 struct nlist *p; 76 int fscale, i; 77 78 if (ISALIVE(kd)) 79 return (getloadavg(loadavg, nelem)); 80 81 if (kvm_nlist(kd, nl) != 0) { 82 for (p = nl; p->n_type != 0; ++p); 83 _kvm_err(kd, kd->program, 84 "%s: no such symbol", p->n_name); 85 return (-1); 86 } 87 88 #define KREAD(kd, addr, obj) \ 89 (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) 90 if (KREAD(kd, nl[X_AVERUNNABLE].n_value, &loadinfo)) { 91 _kvm_err(kd, kd->program, "can't read averunnable"); 92 return (-1); 93 } 94 95 /* 96 * Old kernels have fscale separately; if not found assume 97 * running new format. 98 */ 99 if (!KREAD(kd, nl[X_FSCALE].n_value, &fscale)) 100 loadinfo.fscale = fscale; 101 102 nelem = MIN(nelem, sizeof(loadinfo.ldavg) / sizeof(fixpt_t)); 103 for (i = 0; i < nelem; i++) 104 loadavg[i] = (double) loadinfo.ldavg[i] / loadinfo.fscale; 105 return (nelem); 106 } 107