xref: /netbsd-src/sys/conf/param.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: param.c,v 1.69 2020/11/12 07:44:01 simonb 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 1.69 2020/11/12 07:44:01 simonb 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 #endif
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/socket.h>
53 #include <sys/socketvar.h>
54 #include <sys/proc.h>
55 #include <sys/vnode.h>
56 #include <sys/file.h>
57 #include <sys/callout.h>
58 #include <sys/mbuf.h>
59 #include <ufs/ufs/quota.h>
60 #include <sys/kernel.h>
61 #include <sys/utsname.h>
62 #include <sys/lwp.h>
63 #ifdef SYSVSHM
64 #include <machine/vmparam.h>
65 #include <sys/shm.h>
66 #endif
67 #ifdef SYSVSEM
68 #include <sys/sem.h>
69 #endif
70 #ifdef SYSVMSG
71 #include <sys/msg.h>
72 #endif
73 
74 /*
75  * PCC cannot handle the 80KB string literal.
76  */
77 #if !defined(__PCC__)
78 #define CONFIG_FILE
79 #include "config_file.h"
80 #endif
81 
82 /*
83  * System parameter formulae.
84  *
85  * This file is copied into each directory where we compile
86  * the kernel; it should be modified there to suit local taste
87  * if necessary.
88  *
89  * Compiled with -DHZ=xx -DRTC_OFFSET=x -DMAXUSERS=xx
90  */
91 
92 #ifdef TIMEZONE
93 #error TIMEZONE is an obsolete kernel option.
94 #endif
95 
96 #ifdef DST
97 #error DST is an obsolete kernel option.
98 #endif
99 
100 #ifndef RTC_OFFSET
101 #define RTC_OFFSET 0
102 #endif
103 
104 #ifndef HZ
105 #define	HZ 100
106 #endif
107 
108 #ifndef MAXEXEC
109 #define	MAXEXEC		16
110 #endif
111 
112 int	hz = HZ;
113 int	tick = 1000000 / HZ;
114 /* can adjust 240ms in 60s */
115 int	tickadj = (240000 / (60 * HZ)) ? (240000 / (60 * HZ)) : 1;
116 int	rtc_offset = RTC_OFFSET;
117 int	maxproc = NPROC;
118 int	maxlwp = MAXLWP;
119 int	desiredvnodes = NVNODE;
120 u_int	maxfiles = MAXFILES;
121 int	fscale = FSCALE;	/* kernel uses `FSCALE', user uses `fscale' */
122 int	maxexec = MAXEXEC;	/* max number of concurrent exec() calls */
123 
124 #ifdef MULTIPROCESSOR
125 u_int	maxcpus = MAXCPUS;
126 size_t	coherency_unit = COHERENCY_UNIT;
127 #else
128 u_int	maxcpus = 1;
129 size_t	coherency_unit = ALIGNBYTES + 1;
130 #endif
131 
132 /*
133  * Various mbuf-related parameters.  These can also be changed at run-time
134  * with sysctl.
135  */
136 int	nmbclusters = 0;
137 
138 #ifndef MBLOWAT
139 #define	MBLOWAT		16
140 #endif
141 int	mblowat = MBLOWAT;
142 
143 #ifndef MCLLOWAT
144 #define	MCLLOWAT	8
145 #endif
146 int	mcllowat = MCLLOWAT;
147 
148 /*
149  * Actual network mbuf sizes (read-only), for netstat.
150  */
151 const	int msize = MSIZE;
152 const	int mclbytes = MCLBYTES;
153