xref: /freebsd/sys/kern/subr_param.c (revision 54ebdd631db8c0bba2baab0155f603a8b5cf014a)
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 #  ifndef HZ_VM
61 #    define	HZ_VM 10
62 #  endif
63 #else
64 #  ifndef HZ_VM
65 #    define	HZ_VM HZ
66 #  endif
67 #endif
68 #define	NPROC (20 + 16 * maxusers)
69 #ifndef NBUF
70 #define NBUF 0
71 #endif
72 #ifndef MAXFILES
73 #define	MAXFILES (maxproc * 2)
74 #endif
75 
76 int	hz;
77 int	tick;
78 int	maxusers;			/* base tunable */
79 int	maxproc;			/* maximum # of processes */
80 int	maxprocperuid;			/* max # of procs per user */
81 int	maxfiles;			/* sys. wide open files limit */
82 int	maxfilesperproc;		/* per-proc open files limit */
83 int	ncallout;			/* maximum # of timer events */
84 int	nbuf;
85 int	nswbuf;
86 int	maxswzone;			/* max swmeta KVA storage */
87 int	maxbcache;			/* max buffer cache KVA storage */
88 int	maxpipekva;			/* Limit on pipe KVA */
89 u_long	maxtsiz;			/* max text size */
90 u_long	dfldsiz;			/* initial data size limit */
91 u_long	maxdsiz;			/* max data size */
92 u_long	dflssiz;			/* initial stack size limit */
93 u_long	maxssiz;			/* max stack size */
94 u_long	sgrowsiz;			/* amount to grow stack */
95 
96 SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN, &hz, 0, "ticks/second");
97 SYSCTL_INT(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0,
98     "max swmeta KVA storage");
99 SYSCTL_INT(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN, &maxbcache, 0,
100     "max buffer cache KVA storage");
101 SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RDTUN, &maxtsiz, 0,
102     "max text size");
103 SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RDTUN, &dfldsiz, 0,
104     "initial data size limit");
105 SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RDTUN, &maxdsiz, 0,
106     "max data size");
107 SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RDTUN, &dflssiz, 0,
108     "initial stack size limit");
109 SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RDTUN, &maxssiz, 0,
110     "max stack size");
111 SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RDTUN, &sgrowsiz, 0,
112     "amount to grow stack");
113 
114 /*
115  * These have to be allocated somewhere; allocating
116  * them here forces loader errors if this file is omitted
117  * (if they've been externed everywhere else; hah!).
118  */
119 struct	buf *swbuf;
120 
121 static const char *const vm_bnames[] = {
122 	"QEMU",				/* QEMU */
123 	"Plex86",			/* Plex86 */
124 	"Bochs",			/* Bochs */
125 	NULL
126 };
127 
128 static const char *const vm_pnames[] = {
129 	"VMware Virtual Platform",	/* VMWare VM */
130 	"Virtual Machine",		/* Microsoft VirtualPC */
131 	"VirtualBox",			/* Sun xVM VirtualBox */
132 	"Parallels Virtual Platform",	/* Parallels VM */
133 	NULL
134 };
135 
136 static int
137 detect_virtual(void)
138 {
139 	char *sysenv;
140 	int i;
141 
142 	sysenv = getenv("smbios.bios.vendor");
143 	if (sysenv != NULL) {
144 		for (i = 0; vm_bnames[i] != NULL; i++)
145 			if (strcmp(sysenv, vm_bnames[i]) == 0) {
146 				freeenv(sysenv);
147 				return (1);
148 			}
149 		freeenv(sysenv);
150 	}
151 	sysenv = getenv("smbios.system.product");
152 	if (sysenv != NULL) {
153 		for (i = 0; vm_pnames[i] != NULL; i++)
154 			if (strcmp(sysenv, vm_pnames[i]) == 0) {
155 				freeenv(sysenv);
156 				return (1);
157 			}
158 		freeenv(sysenv);
159 	}
160 	return (0);
161 }
162 
163 /*
164  * Boot time overrides that are not scaled against main memory
165  */
166 void
167 init_param1(void)
168 {
169 
170 	hz = -1;
171 	TUNABLE_INT_FETCH("kern.hz", &hz);
172 	if (hz == -1)
173 		hz = detect_virtual() ? HZ_VM : HZ;
174 	tick = 1000000 / hz;
175 
176 #ifdef VM_SWZONE_SIZE_MAX
177 	maxswzone = VM_SWZONE_SIZE_MAX;
178 #endif
179 	TUNABLE_INT_FETCH("kern.maxswzone", &maxswzone);
180 #ifdef VM_BCACHE_SIZE_MAX
181 	maxbcache = VM_BCACHE_SIZE_MAX;
182 #endif
183 	TUNABLE_INT_FETCH("kern.maxbcache", &maxbcache);
184 
185 	maxtsiz = MAXTSIZ;
186 	TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz);
187 	dfldsiz = DFLDSIZ;
188 	TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz);
189 	maxdsiz = MAXDSIZ;
190 	TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz);
191 	dflssiz = DFLSSIZ;
192 	TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz);
193 	maxssiz = MAXSSIZ;
194 	TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz);
195 	sgrowsiz = SGROWSIZ;
196 	TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz);
197 }
198 
199 /*
200  * Boot time overrides that are scaled against main memory
201  */
202 void
203 init_param2(long physpages)
204 {
205 
206 	/* Base parameters */
207 	maxusers = MAXUSERS;
208 	TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
209 	if (maxusers == 0) {
210 		maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE);
211 		if (maxusers < 32)
212 			maxusers = 32;
213 		if (maxusers > 384)
214 			maxusers = 384;
215 	}
216 
217 	/*
218 	 * The following can be overridden after boot via sysctl.  Note:
219 	 * unless overriden, these macros are ultimately based on maxusers.
220 	 */
221 	maxproc = NPROC;
222 	TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
223 	/*
224 	 * Limit maxproc so that kmap entries cannot be exhausted by
225 	 * processes.
226 	 */
227 	if (maxproc > (physpages / 12))
228 		maxproc = physpages / 12;
229 	maxfiles = MAXFILES;
230 	TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
231 	maxprocperuid = (maxproc * 9) / 10;
232 	maxfilesperproc = (maxfiles * 9) / 10;
233 
234 	/*
235 	 * Cannot be changed after boot.
236 	 */
237 	nbuf = NBUF;
238 	TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
239 
240 	ncallout = 16 + maxproc + maxfiles;
241 	TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
242 }
243 
244 /*
245  * Boot time overrides that are scaled against the kmem map
246  */
247 void
248 init_param3(long kmempages)
249 {
250 
251 	/*
252 	 * The default for maxpipekva is max(5% of the kmem map, 512KB).
253 	 * See sys_pipe.c for more details.
254 	 */
255 	maxpipekva = (kmempages / 20) * PAGE_SIZE;
256 	if (maxpipekva < 512 * 1024)
257 		maxpipekva = 512 * 1024;
258 	TUNABLE_INT_FETCH("kern.ipc.maxpipekva", &maxpipekva);
259 }
260