11573Srgrimes/*- 21573Srgrimes * Copyright (c) 1993 31573Srgrimes * The Regents of the University of California. All rights reserved. 41573Srgrimes * 51573Srgrimes * Redistribution and use in source and binary forms, with or without 61573Srgrimes * modification, are permitted provided that the following conditions 71573Srgrimes * are met: 81573Srgrimes * 1. Redistributions of source code must retain the above copyright 91573Srgrimes * notice, this list of conditions and the following disclaimer. 101573Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111573Srgrimes * notice, this list of conditions and the following disclaimer in the 121573Srgrimes * documentation and/or other materials provided with the distribution. 131573Srgrimes * 4. Neither the name of the University nor the names of its contributors 141573Srgrimes * may be used to endorse or promote products derived from this software 151573Srgrimes * without specific prior written permission. 161573Srgrimes * 171573Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 181573Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 191573Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 201573Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 211573Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 221573Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 231573Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 241573Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 251573Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 261573Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 271573Srgrimes * SUCH DAMAGE. 281573Srgrimes */ 291573Srgrimes 3083551Sdillon#include <sys/cdefs.h> 3183551Sdillon__FBSDID("$FreeBSD: releng/10.3/lib/libkvm/kvm_getloadavg.c 217744 2011-01-23 11:08:28Z uqs $"); 3283551Sdillon 331573Srgrimes#if defined(LIBC_SCCS) && !defined(lint) 3455127Speter#if 0 351573Srgrimesstatic char sccsid[] = "@(#)kvm_getloadavg.c 8.1 (Berkeley) 6/4/93"; 3655127Speter#endif 371573Srgrimes#endif /* LIBC_SCCS and not lint */ 381573Srgrimes 3986646Sjhb#include <sys/param.h> 4086625Srwatson#include <sys/time.h> 4186625Srwatson#include <sys/resource.h> 421573Srgrimes 4317141Sjkh#include <stdlib.h> 441573Srgrimes#include <limits.h> 451573Srgrimes#include <nlist.h> 461573Srgrimes#include <kvm.h> 471573Srgrimes 481573Srgrimes#include "kvm_private.h" 491573Srgrimes 501573Srgrimesstatic struct nlist nl[] = { 51217744Suqs { .n_name = "_averunnable" }, 521573Srgrimes#define X_AVERUNNABLE 0 53217744Suqs { .n_name = "_fscale" }, 541573Srgrimes#define X_FSCALE 1 55217744Suqs { .n_name = "" }, 561573Srgrimes}; 571573Srgrimes 581573Srgrimes/* 591573Srgrimes * kvm_getloadavg() -- Get system load averages, from live or dead kernels. 601573Srgrimes * 611573Srgrimes * Put `nelem' samples into `loadavg' array. 621573Srgrimes * Return number of samples retrieved, or -1 on error. 631573Srgrimes */ 641573Srgrimesint 65217744Suqskvm_getloadavg(kvm_t *kd, double loadavg[], int nelem) 661573Srgrimes{ 671573Srgrimes struct loadavg loadinfo; 681573Srgrimes struct nlist *p; 691573Srgrimes int fscale, i; 701573Srgrimes 711573Srgrimes if (ISALIVE(kd)) 721573Srgrimes return (getloadavg(loadavg, nelem)); 731573Srgrimes 741573Srgrimes if (kvm_nlist(kd, nl) != 0) { 751573Srgrimes for (p = nl; p->n_type != 0; ++p); 761573Srgrimes _kvm_err(kd, kd->program, 771573Srgrimes "%s: no such symbol", p->n_name); 781573Srgrimes return (-1); 791573Srgrimes } 801573Srgrimes 811573Srgrimes#define KREAD(kd, addr, obj) \ 821573Srgrimes (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) 831573Srgrimes if (KREAD(kd, nl[X_AVERUNNABLE].n_value, &loadinfo)) { 841573Srgrimes _kvm_err(kd, kd->program, "can't read averunnable"); 851573Srgrimes return (-1); 861573Srgrimes } 871573Srgrimes 881573Srgrimes /* 891573Srgrimes * Old kernels have fscale separately; if not found assume 901573Srgrimes * running new format. 911573Srgrimes */ 921573Srgrimes if (!KREAD(kd, nl[X_FSCALE].n_value, &fscale)) 931573Srgrimes loadinfo.fscale = fscale; 941573Srgrimes 95217744Suqs nelem = MIN(nelem, (int)(sizeof(loadinfo.ldavg) / sizeof(fixpt_t))); 961573Srgrimes for (i = 0; i < nelem; i++) 971573Srgrimes loadavg[i] = (double) loadinfo.ldavg[i] / loadinfo.fscale; 981573Srgrimes return (nelem); 991573Srgrimes} 100