subr_param.c revision 80418
1/* 2 * Copyright (c) 1980, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)param.c 8.3 (Berkeley) 8/20/94 39 * $FreeBSD: head/sys/kern/subr_param.c 80418 2001-07-26 23:04:03Z peter $ 40 */ 41 42#include "opt_param.h" 43#include "opt_maxusers.h" 44 45#include <sys/param.h> 46#include <sys/systm.h> 47#include <sys/kernel.h> 48 49/* 50 * System parameter formulae. 51 */ 52 53#ifndef HZ 54#define HZ 100 55#endif 56#define NPROC (20 + 16 * maxusers) 57#ifndef NBUF 58#define NBUF 0 59#endif 60#ifndef MAXFILES 61#define MAXFILES (maxproc * 2) 62#endif 63 64int hz; 65int tick; 66int tickadj; /* can adjust 30ms in 60s */ 67int maxusers; /* base tunable */ 68int maxproc; /* maximum # of processes */ 69int maxprocperuid; /* max # of procs per user */ 70int maxfiles; /* sys. wide open files limit */ 71int maxfilesperproc; /* per-proc open files limit */ 72int ncallout; /* maximum # of timer events */ 73int nbuf; 74int nswbuf; 75 76/* 77 * These have to be allocated somewhere; allocating 78 * them here forces loader errors if this file is omitted 79 * (if they've been externed everywhere else; hah!). 80 */ 81struct buf *swbuf; 82 83/* 84 * Total number of shared mutexes to protect all lockmgr locks. 85 */ 86#ifndef LOCKMUTEX 87#define LOCKMUTEX 10 88#endif 89int lock_nmtx = LOCKMUTEX; 90 91/* 92 * Boot time overrides 93 */ 94void 95init_param(void) 96{ 97 98 /* Base parameters */ 99 maxusers = MAXUSERS; 100 TUNABLE_INT_FETCH("kern.maxusers", &maxusers); 101 hz = HZ; 102 TUNABLE_INT_FETCH("kern.hz", &hz); 103 tick = 1000000 / hz; 104 tickadj = howmany(30000, 60 * hz); /* can adjust 30ms in 60s */ 105 106 /* The following can be overridden after boot via sysctl */ 107 maxproc = NPROC; 108 TUNABLE_INT_FETCH("kern.maxproc", &maxproc); 109 maxfiles = MAXFILES; 110 TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles); 111 maxprocperuid = maxproc - 1; 112 maxfilesperproc = maxfiles; 113 114 /* Cannot be changed after boot */ 115 nbuf = NBUF; 116 TUNABLE_INT_FETCH("kern.nbuf", &nbuf); 117 ncallout = 16 + maxproc + maxfiles; 118 TUNABLE_INT_FETCH("kern.ncallout", &ncallout); 119} 120