Deleted Added
sdiff udiff text old ( 242847 ) new ( 243631 )
full compact
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: head/sys/kern/subr_param.c 242847 2012-11-10 02:08:40Z alfred $");
39
40#include "opt_param.h"
41#include "opt_msgbuf.h"
42#include "opt_maxusers.h"
43
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/kernel.h>
47#include <sys/limits.h>
48#include <sys/msgbuf.h>
49#include <sys/sysctl.h>
50#include <sys/proc.h>
51
52#include <vm/vm.h>
53#include <vm/vm_param.h>
54#include <vm/pmap.h>
55
56/*
57 * System parameter formulae.
58 */
59
60#ifndef HZ
61# if defined(__mips__) || defined(__arm__)
62# define HZ 100
63# else
64# define HZ 1000
65# endif
66# ifndef HZ_VM
67# define HZ_VM 100
68# endif
69#else
70# ifndef HZ_VM
71# define HZ_VM HZ
72# endif
73#endif
74#define NPROC (20 + 16 * maxusers)
75#ifndef NBUF
76#define NBUF 0
77#endif
78#ifndef MAXFILES
79#define MAXFILES (maxproc * 2)
80#endif
81
82static int sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS);
83
84int hz;
85int tick;
86int maxusers; /* base tunable */
87int maxproc; /* maximum # of processes */
88int maxprocperuid; /* max # of procs per user */
89int maxfiles; /* sys. wide open files limit */
90int maxfilesperproc; /* per-proc open files limit */
91int msgbufsize; /* size of kernel message buffer */
92int ncallout; /* maximum # of timer events */
93int nbuf;
94int ngroups_max; /* max # groups per process */
95int nswbuf;
96pid_t pid_max = PID_MAX;
97long maxswzone; /* max swmeta KVA storage */
98long maxbcache; /* max buffer cache KVA storage */
99long maxpipekva; /* Limit on pipe KVA */
100int vm_guest; /* Running as virtual machine guest? */
101u_long maxtsiz; /* max text size */
102u_long dfldsiz; /* initial data size limit */
103u_long maxdsiz; /* max data size */
104u_long dflssiz; /* initial stack size limit */
105u_long maxssiz; /* max stack size */
106u_long sgrowsiz; /* amount to grow stack */
107
108SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN, &hz, 0,
109 "Number of clock ticks per second");
110SYSCTL_INT(_kern, OID_AUTO, ncallout, CTLFLAG_RDTUN, &ncallout, 0,
111 "Number of pre-allocated timer events");
112SYSCTL_INT(_kern, OID_AUTO, nbuf, CTLFLAG_RDTUN, &nbuf, 0,
113 "Number of buffers in the buffer cache");
114SYSCTL_INT(_kern, OID_AUTO, nswbuf, CTLFLAG_RDTUN, &nswbuf, 0,
115 "Number of swap buffers");
116SYSCTL_INT(_kern, OID_AUTO, msgbufsize, CTLFLAG_RDTUN, &msgbufsize, 0,
117 "Size of the kernel message buffer");
118SYSCTL_LONG(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0,
119 "Maximum memory for swap metadata");
120SYSCTL_LONG(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN, &maxbcache, 0,
121 "Maximum value of vfs.maxbufspace");
122SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RW | CTLFLAG_TUN, &maxtsiz, 0,
123 "Maximum text size");
124SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RW | CTLFLAG_TUN, &dfldsiz, 0,
125 "Initial data size limit");
126SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RW | CTLFLAG_TUN, &maxdsiz, 0,
127 "Maximum data size");
128SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RW | CTLFLAG_TUN, &dflssiz, 0,
129 "Initial stack size limit");
130SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RW | CTLFLAG_TUN, &maxssiz, 0,
131 "Maximum stack size");
132SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RW | CTLFLAG_TUN, &sgrowsiz, 0,
133 "Amount to grow stack on a stack fault");
134SYSCTL_PROC(_kern, OID_AUTO, vm_guest, CTLFLAG_RD | CTLTYPE_STRING,
135 NULL, 0, sysctl_kern_vm_guest, "A",
136 "Virtual machine guest detected? (none|generic|xen)");
137
138/*
139 * These have to be allocated somewhere; allocating
140 * them here forces loader errors if this file is omitted
141 * (if they've been externed everywhere else; hah!).
142 */
143struct buf *swbuf;
144
145/*
146 * The elements of this array are ordered based upon the values of the
147 * corresponding enum VM_GUEST members.
148 */
149static const char *const vm_guest_sysctl_names[] = {
150 "none",
151 "generic",
152 "xen",
153 NULL
154};
155
156#ifndef XEN
157static const char *const vm_bnames[] = {
158 "QEMU", /* QEMU */
159 "Plex86", /* Plex86 */
160 "Bochs", /* Bochs */
161 "Xen", /* Xen */
162 NULL
163};
164
165static const char *const vm_pnames[] = {
166 "VMware Virtual Platform", /* VMWare VM */
167 "Virtual Machine", /* Microsoft VirtualPC */
168 "VirtualBox", /* Sun xVM VirtualBox */
169 "Parallels Virtual Platform", /* Parallels VM */
170 NULL
171};
172
173
174/*
175 * Detect known Virtual Machine hosts by inspecting the emulated BIOS.
176 */
177static enum VM_GUEST
178detect_virtual(void)
179{
180 char *sysenv;
181 int i;
182
183 sysenv = getenv("smbios.bios.vendor");
184 if (sysenv != NULL) {
185 for (i = 0; vm_bnames[i] != NULL; i++)
186 if (strcmp(sysenv, vm_bnames[i]) == 0) {
187 freeenv(sysenv);
188 return (VM_GUEST_VM);
189 }
190 freeenv(sysenv);
191 }
192 sysenv = getenv("smbios.system.product");
193 if (sysenv != NULL) {
194 for (i = 0; vm_pnames[i] != NULL; i++)
195 if (strcmp(sysenv, vm_pnames[i]) == 0) {
196 freeenv(sysenv);
197 return (VM_GUEST_VM);
198 }
199 freeenv(sysenv);
200 }
201 return (VM_GUEST_NO);
202}
203#endif
204
205/*
206 * Boot time overrides that are not scaled against main memory
207 */
208void
209init_param1(void)
210{
211#ifndef XEN
212 vm_guest = detect_virtual();
213#else
214 vm_guest = VM_GUEST_XEN;
215#endif
216 hz = -1;
217 TUNABLE_INT_FETCH("kern.hz", &hz);
218 if (hz == -1)
219 hz = vm_guest > VM_GUEST_NO ? HZ_VM : HZ;
220 tick = 1000000 / hz;
221
222#ifdef VM_SWZONE_SIZE_MAX
223 maxswzone = VM_SWZONE_SIZE_MAX;
224#endif
225 TUNABLE_LONG_FETCH("kern.maxswzone", &maxswzone);
226#ifdef VM_BCACHE_SIZE_MAX
227 maxbcache = VM_BCACHE_SIZE_MAX;
228#endif
229 TUNABLE_LONG_FETCH("kern.maxbcache", &maxbcache);
230 msgbufsize = MSGBUF_SIZE;
231 TUNABLE_INT_FETCH("kern.msgbufsize", &msgbufsize);
232
233 maxtsiz = MAXTSIZ;
234 TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz);
235 dfldsiz = DFLDSIZ;
236 TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz);
237 maxdsiz = MAXDSIZ;
238 TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz);
239 dflssiz = DFLSSIZ;
240 TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz);
241 maxssiz = MAXSSIZ;
242 TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz);
243 sgrowsiz = SGROWSIZ;
244 TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz);
245
246 /*
247 * Let the administrator set {NGROUPS_MAX}, but disallow values
248 * less than NGROUPS_MAX which would violate POSIX.1-2008 or
249 * greater than INT_MAX-1 which would result in overflow.
250 */
251 ngroups_max = NGROUPS_MAX;
252 TUNABLE_INT_FETCH("kern.ngroups", &ngroups_max);
253 if (ngroups_max < NGROUPS_MAX)
254 ngroups_max = NGROUPS_MAX;
255
256 /*
257 * Only allow to lower the maximal pid.
258 * Prevent setting up a non-bootable system if pid_max is too low.
259 */
260 TUNABLE_INT_FETCH("kern.pid_max", &pid_max);
261 if (pid_max > PID_MAX)
262 pid_max = PID_MAX;
263 else if (pid_max < 300)
264 pid_max = 300;
265}
266
267/*
268 * Boot time overrides that are scaled against main memory
269 */
270void
271init_param2(long physpages)
272{
273
274 /* Base parameters */
275 maxusers = MAXUSERS;
276 TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
277 if (maxusers == 0) {
278 maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE);
279 if (maxusers < 32)
280 maxusers = 32;
281#ifdef VM_MAX_AUTOTUNE_MAXUSERS
282 if (maxusers > VM_MAX_AUTOTUNE_MAXUSERS)
283 maxusers = VM_MAX_AUTOTUNE_MAXUSERS;
284#endif
285 /*
286 * Scales down the function in which maxusers grows once
287 * we hit 384.
288 */
289 if (maxusers > 384)
290 maxusers = 384 + ((maxusers - 384) / 8);
291 }
292
293 /*
294 * The following can be overridden after boot via sysctl. Note:
295 * unless overriden, these macros are ultimately based on maxusers.
296 */
297 maxproc = NPROC;
298 TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
299 /*
300 * Limit maxproc so that kmap entries cannot be exhausted by
301 * processes.
302 */
303 if (maxproc > (physpages / 12))
304 maxproc = physpages / 12;
305 maxfiles = MAXFILES;
306 TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
307 maxprocperuid = (maxproc * 9) / 10;
308 maxfilesperproc = (maxfiles * 9) / 10;
309
310 /*
311 * Cannot be changed after boot.
312 */
313 nbuf = NBUF;
314 TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
315
316 ncallout = 16 + maxproc + maxfiles;
317 TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
318
319 /*
320 * The default for maxpipekva is min(1/64 of the kernel address space,
321 * max(1/64 of main memory, 512KB)). See sys_pipe.c for more details.
322 */
323 maxpipekva = (physpages / 64) * PAGE_SIZE;
324 if (maxpipekva < 512 * 1024)
325 maxpipekva = 512 * 1024;
326 if (maxpipekva > (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / 64)
327 maxpipekva = (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) /
328 64;
329 TUNABLE_LONG_FETCH("kern.ipc.maxpipekva", &maxpipekva);
330}
331
332/*
333 * Sysctl stringiying handler for kern.vm_guest.
334 */
335static int
336sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS)
337{
338 return (SYSCTL_OUT(req, vm_guest_sysctl_names[vm_guest],
339 strlen(vm_guest_sysctl_names[vm_guest])));
340}