xref: /freebsd/sys/kern/subr_param.c (revision cacdd70cc751fb68dec4b86c5e5b8c969b6e26ef)
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  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)param.c	8.3 (Berkeley) 8/20/94
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include "opt_param.h"
41 #include "opt_maxusers.h"
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
46 #include <sys/sysctl.h>
47 
48 #include <vm/vm_param.h>
49 
50 /*
51  * System parameter formulae.
52  */
53 
54 #ifndef HZ
55 #  if defined(__amd64__) || defined(__i386__) || defined(__ia64__) || defined(__sparc64__)
56 #    define	HZ 1000
57 #  else
58 #    define	HZ 100
59 #  endif
60 #endif
61 #define	NPROC (20 + 16 * maxusers)
62 #ifndef NBUF
63 #define NBUF 0
64 #endif
65 #ifndef MAXFILES
66 #define	MAXFILES (maxproc * 2)
67 #endif
68 
69 int	hz;
70 int	tick;
71 int	maxusers;			/* base tunable */
72 int	maxproc;			/* maximum # of processes */
73 int	maxprocperuid;			/* max # of procs per user */
74 int	maxfiles;			/* sys. wide open files limit */
75 int	maxfilesperproc;		/* per-proc open files limit */
76 int	ncallout;			/* maximum # of timer events */
77 int	nbuf;
78 int	nswbuf;
79 int	maxswzone;			/* max swmeta KVA storage */
80 int	maxbcache;			/* max buffer cache KVA storage */
81 int	maxpipekva;			/* Limit on pipe KVA */
82 u_long	maxtsiz;			/* max text size */
83 u_long	dfldsiz;			/* initial data size limit */
84 u_long	maxdsiz;			/* max data size */
85 u_long	dflssiz;			/* initial stack size limit */
86 u_long	maxssiz;			/* max stack size */
87 u_long	sgrowsiz;			/* amount to grow stack */
88 
89 SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN, &hz, 0, "ticks/second");
90 SYSCTL_INT(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0,
91     "max swmeta KVA storage");
92 SYSCTL_INT(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN, &maxbcache, 0,
93     "max buffer cache KVA storage");
94 SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RDTUN, &maxtsiz, 0,
95     "max text size");
96 SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RDTUN, &dfldsiz, 0,
97     "initial data size limit");
98 SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RDTUN, &maxdsiz, 0,
99     "max data size");
100 SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RDTUN, &dflssiz, 0,
101     "initial stack size limit");
102 SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RDTUN, &maxssiz, 0,
103     "max stack size");
104 SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RDTUN, &sgrowsiz, 0,
105     "amount to grow stack");
106 
107 /*
108  * These have to be allocated somewhere; allocating
109  * them here forces loader errors if this file is omitted
110  * (if they've been externed everywhere else; hah!).
111  */
112 struct	buf *swbuf;
113 
114 /*
115  * Boot time overrides that are not scaled against main memory
116  */
117 void
118 init_param1(void)
119 {
120 
121 	hz = HZ;
122 	TUNABLE_INT_FETCH("kern.hz", &hz);
123 	tick = 1000000 / hz;
124 
125 #ifdef VM_SWZONE_SIZE_MAX
126 	maxswzone = VM_SWZONE_SIZE_MAX;
127 #endif
128 	TUNABLE_INT_FETCH("kern.maxswzone", &maxswzone);
129 #ifdef VM_BCACHE_SIZE_MAX
130 	maxbcache = VM_BCACHE_SIZE_MAX;
131 #endif
132 	TUNABLE_INT_FETCH("kern.maxbcache", &maxbcache);
133 
134 	maxtsiz = MAXTSIZ;
135 	TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz);
136 	dfldsiz = DFLDSIZ;
137 	TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz);
138 	maxdsiz = MAXDSIZ;
139 	TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz);
140 	dflssiz = DFLSSIZ;
141 	TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz);
142 	maxssiz = MAXSSIZ;
143 	TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz);
144 	sgrowsiz = SGROWSIZ;
145 	TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz);
146 }
147 
148 /*
149  * Boot time overrides that are scaled against main memory
150  */
151 void
152 init_param2(long physpages)
153 {
154 
155 	/* Base parameters */
156 	maxusers = MAXUSERS;
157 	TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
158 	if (maxusers == 0) {
159 		maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE);
160 		if (maxusers < 32)
161 			maxusers = 32;
162 		if (maxusers > 384)
163 			maxusers = 384;
164 	}
165 
166 	/*
167 	 * The following can be overridden after boot via sysctl.  Note:
168 	 * unless overriden, these macros are ultimately based on maxusers.
169 	 */
170 	maxproc = NPROC;
171 	TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
172 	/*
173 	 * Limit maxproc so that kmap entries cannot be exhausted by
174 	 * processes.
175 	 */
176 	if (maxproc > (physpages / 12))
177 		maxproc = physpages / 12;
178 	maxfiles = MAXFILES;
179 	TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
180 	maxprocperuid = (maxproc * 9) / 10;
181 	maxfilesperproc = (maxfiles * 9) / 10;
182 
183 	/*
184 	 * Cannot be changed after boot.
185 	 */
186 	nbuf = NBUF;
187 	TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
188 
189 	ncallout = 16 + maxproc + maxfiles;
190 	TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
191 }
192 
193 /*
194  * Boot time overrides that are scaled against the kmem map
195  */
196 void
197 init_param3(long kmempages)
198 {
199 
200 	/*
201 	 * The default for maxpipekva is max(5% of the kmem map, 512KB).
202 	 * See sys_pipe.c for more details.
203 	 */
204 	maxpipekva = (kmempages / 20) * PAGE_SIZE;
205 	if (maxpipekva < 512 * 1024)
206 		maxpipekva = 512 * 1024;
207 	TUNABLE_INT_FETCH("kern.ipc.maxpipekva", &maxpipekva);
208 }
209