subr_param.c revision 189649
1146773Ssam/*- 2146773Ssam * Copyright (c) 1980, 1986, 1989, 1993 3146773Ssam * The Regents of the University of California. All rights reserved. 4146773Ssam * (c) UNIX System Laboratories, Inc. 5146773Ssam * All or some portions of this file are derived from material licensed 6146773Ssam * to the University of California by American Telephone and Telegraph 7146773Ssam * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8146773Ssam * the permission of UNIX System Laboratories, Inc. 9146773Ssam * 10146773Ssam * Redistribution and use in source and binary forms, with or without 11146773Ssam * modification, are permitted provided that the following conditions 12146773Ssam * are met: 13146773Ssam * 1. Redistributions of source code must retain the above copyright 14285275Spkelsey * notice, this list of conditions and the following disclaimer. 15285275Spkelsey * 2. Redistributions in binary form must reproduce the above copyright 16146773Ssam * notice, this list of conditions and the following disclaimer in the 17146773Ssam * documentation and/or other materials provided with the distribution. 18313537Sglebius * 4. Neither the name of the University nor the names of its contributors 19313537Sglebius * may be used to endorse or promote products derived from this software 20146773Ssam * without specific prior written permission. 21146773Ssam * 22146773Ssam * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23146773Ssam * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24313537Sglebius * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25146773Ssam * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26313537Sglebius * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27146773Ssam * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28146773Ssam * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29285275Spkelsey * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30285275Spkelsey * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31285275Spkelsey * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32285275Spkelsey * SUCH DAMAGE. 33285275Spkelsey * 34285275Spkelsey * @(#)param.c 8.3 (Berkeley) 8/20/94 35285275Spkelsey */ 36285275Spkelsey 37285275Spkelsey#include <sys/cdefs.h> 38285275Spkelsey__FBSDID("$FreeBSD: head/sys/kern/subr_param.c 189649 2009-03-10 21:28:43Z jhb $"); 39285275Spkelsey 40285275Spkelsey#include "opt_param.h" 41285275Spkelsey#include "opt_maxusers.h" 42285275Spkelsey 43285275Spkelsey#include <sys/param.h> 44285275Spkelsey#include <sys/systm.h> 45285275Spkelsey#include <sys/kernel.h> 46285275Spkelsey#include <sys/sysctl.h> 47285275Spkelsey 48285275Spkelsey#include <vm/vm_param.h> 49285275Spkelsey 50146773Ssam/* 51285275Spkelsey * System parameter formulae. 52146773Ssam */ 53285275Spkelsey 54146773Ssam#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/* Values of enum VM_GUEST members are used as indices in 77 * vm_guest_sysctl_names */ 78enum VM_GUEST { VM_GUEST_NO = 0, VM_GUEST_VM, VM_GUEST_XEN }; 79 80static int sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS); 81 82int hz; 83int tick; 84int maxusers; /* base tunable */ 85int maxproc; /* maximum # of processes */ 86int maxprocperuid; /* max # of procs per user */ 87int maxfiles; /* sys. wide open files limit */ 88int maxfilesperproc; /* per-proc open files limit */ 89int ncallout; /* maximum # of timer events */ 90int nbuf; 91int nswbuf; 92long maxswzone; /* max swmeta KVA storage */ 93long maxbcache; /* max buffer cache KVA storage */ 94long maxpipekva; /* Limit on pipe KVA */ 95int vm_guest; /* Running as virtual machine guest? */ 96u_long maxtsiz; /* max text size */ 97u_long dfldsiz; /* initial data size limit */ 98u_long maxdsiz; /* max data size */ 99u_long dflssiz; /* initial stack size limit */ 100u_long maxssiz; /* max stack size */ 101u_long sgrowsiz; /* amount to grow stack */ 102 103SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN, &hz, 0, "ticks/second"); 104SYSCTL_INT(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0, 105 "max swmeta KVA storage"); 106SYSCTL_INT(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN, &maxbcache, 0, 107 "max buffer cache KVA storage"); 108SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RDTUN, &maxtsiz, 0, 109 "max text size"); 110SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RDTUN, &dfldsiz, 0, 111 "initial data size limit"); 112SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RDTUN, &maxdsiz, 0, 113 "max data size"); 114SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RDTUN, &dflssiz, 0, 115 "initial stack size limit"); 116SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RDTUN, &maxssiz, 0, 117 "max stack size"); 118SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RDTUN, &sgrowsiz, 0, 119 "amount to grow stack"); 120SYSCTL_PROC(_kern, OID_AUTO, vm_guest, CTLFLAG_RD | CTLTYPE_STRING, 121 NULL, 0, sysctl_kern_vm_guest, "A", 122 "Virtual machine detected? (none|generic|xen)"); 123 124/* 125 * These have to be allocated somewhere; allocating 126 * them here forces loader errors if this file is omitted 127 * (if they've been externed everywhere else; hah!). 128 */ 129struct buf *swbuf; 130 131static const char *const vm_guest_sysctl_names[] = { 132 "none", 133 "generic", 134 "xen", 135 NULL 136}; 137 138#ifndef XEN 139static const char *const vm_bnames[] = { 140 "QEMU", /* QEMU */ 141 "Plex86", /* Plex86 */ 142 "Bochs", /* Bochs */ 143 NULL 144}; 145 146static const char *const vm_pnames[] = { 147 "VMware Virtual Platform", /* VMWare VM */ 148 "Virtual Machine", /* Microsoft VirtualPC */ 149 "VirtualBox", /* Sun xVM VirtualBox */ 150 "Parallels Virtual Platform", /* Parallels VM */ 151 NULL 152}; 153 154 155/* 156 * Detect known Virtual Machine hosts by inspecting the emulated BIOS. 157 */ 158static enum VM_GUEST 159detect_virtual(void) 160{ 161 char *sysenv; 162 int i; 163 164 sysenv = getenv("smbios.bios.vendor"); 165 if (sysenv != NULL) { 166 for (i = 0; vm_bnames[i] != NULL; i++) 167 if (strcmp(sysenv, vm_bnames[i]) == 0) { 168 freeenv(sysenv); 169 return (VM_GUEST_VM); 170 } 171 freeenv(sysenv); 172 } 173 sysenv = getenv("smbios.system.product"); 174 if (sysenv != NULL) { 175 for (i = 0; vm_pnames[i] != NULL; i++) 176 if (strcmp(sysenv, vm_pnames[i]) == 0) { 177 freeenv(sysenv); 178 return (VM_GUEST_VM); 179 } 180 freeenv(sysenv); 181 } 182 return (VM_GUEST_NO); 183} 184#endif 185 186/* 187 * Boot time overrides that are not scaled against main memory 188 */ 189void 190init_param1(void) 191{ 192#ifndef XEN 193 vm_guest = detect_virtual(); 194#else 195 vm_guest = VM_GUEST_XEN; 196#endif 197 hz = -1; 198 TUNABLE_INT_FETCH("kern.hz", &hz); 199 if (hz == -1) 200 hz = vm_guest > VM_GUEST_NO ? HZ_VM : HZ; 201 tick = 1000000 / hz; 202 203#ifdef VM_SWZONE_SIZE_MAX 204 maxswzone = VM_SWZONE_SIZE_MAX; 205#endif 206 TUNABLE_LONG_FETCH("kern.maxswzone", &maxswzone); 207#ifdef VM_BCACHE_SIZE_MAX 208 maxbcache = VM_BCACHE_SIZE_MAX; 209#endif 210 TUNABLE_LONG_FETCH("kern.maxbcache", &maxbcache); 211 212 maxtsiz = MAXTSIZ; 213 TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz); 214 dfldsiz = DFLDSIZ; 215 TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz); 216 maxdsiz = MAXDSIZ; 217 TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz); 218 dflssiz = DFLSSIZ; 219 TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz); 220 maxssiz = MAXSSIZ; 221 TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz); 222 sgrowsiz = SGROWSIZ; 223 TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz); 224} 225 226/* 227 * Boot time overrides that are scaled against main memory 228 */ 229void 230init_param2(long physpages) 231{ 232 233 /* Base parameters */ 234 maxusers = MAXUSERS; 235 TUNABLE_INT_FETCH("kern.maxusers", &maxusers); 236 if (maxusers == 0) { 237 maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE); 238 if (maxusers < 32) 239 maxusers = 32; 240 if (maxusers > 384) 241 maxusers = 384; 242 } 243 244 /* 245 * The following can be overridden after boot via sysctl. Note: 246 * unless overriden, these macros are ultimately based on maxusers. 247 */ 248 maxproc = NPROC; 249 TUNABLE_INT_FETCH("kern.maxproc", &maxproc); 250 /* 251 * Limit maxproc so that kmap entries cannot be exhausted by 252 * processes. 253 */ 254 if (maxproc > (physpages / 12)) 255 maxproc = physpages / 12; 256 maxfiles = MAXFILES; 257 TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles); 258 maxprocperuid = (maxproc * 9) / 10; 259 maxfilesperproc = (maxfiles * 9) / 10; 260 261 /* 262 * Cannot be changed after boot. 263 */ 264 nbuf = NBUF; 265 TUNABLE_INT_FETCH("kern.nbuf", &nbuf); 266 267 ncallout = 16 + maxproc + maxfiles; 268 TUNABLE_INT_FETCH("kern.ncallout", &ncallout); 269} 270 271/* 272 * Boot time overrides that are scaled against the kmem map 273 */ 274void 275init_param3(long kmempages) 276{ 277 278 /* 279 * The default for maxpipekva is max(5% of the kmem map, 512KB). 280 * See sys_pipe.c for more details. 281 */ 282 maxpipekva = (kmempages / 20) * PAGE_SIZE; 283 if (maxpipekva < 512 * 1024) 284 maxpipekva = 512 * 1024; 285 TUNABLE_LONG_FETCH("kern.ipc.maxpipekva", &maxpipekva); 286} 287 288/* 289 * Sysctl stringiying handler for kern.vm_guest. 290 */ 291static int 292sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS) 293{ 294 return (SYSCTL_OUT(req, vm_guest_sysctl_names[vm_guest], 295 strlen(vm_guest_sysctl_names[vm_guest]))); 296} 297