xref: /netbsd/sys/conf/param.c (revision 3567f89a)
1 /*	$NetBSD: param.c,v 1.70 2022/07/23 19:15:29 mrg Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1986, 1989 Regents of the University of California.
5  * All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)param.c	7.20 (Berkeley) 6/27/91
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: param.c,v 1.70 2022/07/23 19:15:29 mrg Exp $");
41 
42 #ifdef _KERNEL_OPT
43 #include "opt_hz.h"
44 #include "opt_rtc_offset.h"
45 #include "opt_sysv.h"
46 #include "opt_sysvparam.h"
47 #include "opt_multiprocessor.h"
48 #include "opt_maxlwp.h"
49 #endif
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/socket.h>
54 #include <sys/socketvar.h>
55 #include <sys/proc.h>
56 #include <sys/vnode.h>
57 #include <sys/file.h>
58 #include <sys/callout.h>
59 #include <sys/mbuf.h>
60 #include <ufs/ufs/quota.h>
61 #include <sys/kernel.h>
62 #include <sys/utsname.h>
63 #include <sys/lwp.h>
64 #ifdef SYSVSHM
65 #include <machine/vmparam.h>
66 #include <sys/shm.h>
67 #endif
68 #ifdef SYSVSEM
69 #include <sys/sem.h>
70 #endif
71 #ifdef SYSVMSG
72 #include <sys/msg.h>
73 #endif
74 
75 /*
76  * PCC cannot handle the 80KB string literal.
77  */
78 #if !defined(__PCC__)
79 #define CONFIG_FILE
80 #include "config_file.h"
81 #endif
82 
83 /*
84  * System parameter formulae.
85  *
86  * This file is copied into each directory where we compile
87  * the kernel; it should be modified there to suit local taste
88  * if necessary.
89  *
90  * Compiled with -DHZ=xx -DRTC_OFFSET=x -DMAXUSERS=xx
91  */
92 
93 #ifdef TIMEZONE
94 #error TIMEZONE is an obsolete kernel option.
95 #endif
96 
97 #ifdef DST
98 #error DST is an obsolete kernel option.
99 #endif
100 
101 #ifndef RTC_OFFSET
102 #define RTC_OFFSET 0
103 #endif
104 
105 #ifndef HZ
106 #define	HZ 100
107 #endif
108 
109 #ifndef MAXEXEC
110 #define	MAXEXEC		16
111 #endif
112 
113 int	hz = HZ;
114 int	tick = 1000000 / HZ;
115 /* can adjust 240ms in 60s */
116 int	tickadj = (240000 / (60 * HZ)) ? (240000 / (60 * HZ)) : 1;
117 int	rtc_offset = RTC_OFFSET;
118 int	maxproc = NPROC;
119 int	maxlwp = MAXLWP;
120 int	desiredvnodes = NVNODE;
121 u_int	maxfiles = MAXFILES;
122 int	fscale = FSCALE;	/* kernel uses `FSCALE', user uses `fscale' */
123 int	maxexec = MAXEXEC;	/* max number of concurrent exec() calls */
124 
125 #ifdef MULTIPROCESSOR
126 u_int	maxcpus = MAXCPUS;
127 size_t	coherency_unit = COHERENCY_UNIT;
128 #else
129 u_int	maxcpus = 1;
130 size_t	coherency_unit = ALIGNBYTES + 1;
131 #endif
132 
133 /*
134  * Various mbuf-related parameters.  These can also be changed at run-time
135  * with sysctl.
136  */
137 int	nmbclusters = 0;
138 
139 #ifndef MBLOWAT
140 #define	MBLOWAT		16
141 #endif
142 int	mblowat = MBLOWAT;
143 
144 #ifndef MCLLOWAT
145 #define	MCLLOWAT	8
146 #endif
147 int	mcllowat = MCLLOWAT;
148 
149 /*
150  * Actual network mbuf sizes (read-only), for netstat.
151  */
152 const	int msize = MSIZE;
153 const	int mclbytes = MCLBYTES;
154