diff options
Diffstat (limited to 'sys/kern/subr_param.c')
| -rw-r--r-- | sys/kern/subr_param.c | 354 |
1 files changed, 354 insertions, 0 deletions
diff --git a/sys/kern/subr_param.c b/sys/kern/subr_param.c new file mode 100644 index 0000000..a2e822c --- /dev/null +++ b/sys/kern/subr_param.c @@ -0,0 +1,354 @@ +/*- + * Copyright (c) 1980, 1986, 1989, 1993 + * The Regents of the University of California. All rights reserved. + * (c) UNIX System Laboratories, Inc. + * All or some portions of this file are derived from material licensed + * to the University of California by American Telephone and Telegraph + * Co. or Unix System Laboratories, Inc. and are reproduced herein with + * the permission of UNIX System Laboratories, Inc. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)param.c 8.3 (Berkeley) 8/20/94 + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "opt_param.h" +#include "opt_msgbuf.h" +#include "opt_maxusers.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/limits.h> +#include <sys/msgbuf.h> +#include <sys/sysctl.h> +#include <sys/proc.h> + +#include <vm/vm.h> +#include <vm/vm_param.h> +#include <vm/pmap.h> + +/* + * System parameter formulae. + */ + +#ifndef HZ +# if defined(__mips__) || defined(__arm__) +# define HZ 100 +# else +# define HZ 1000 +# endif +# ifndef HZ_VM +# define HZ_VM 100 +# endif +#else +# ifndef HZ_VM +# define HZ_VM HZ +# endif +#endif +#define NPROC (20 + 16 * maxusers) +#ifndef NBUF +#define NBUF 0 +#endif +#ifndef MAXFILES +#define MAXFILES (maxproc * 2) +#endif + +static int sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS); + +int hz; /* system clock's frequency */ +int tick; /* usec per tick (1000000 / hz) */ +struct bintime tick_bt; /* bintime per tick (1s / hz) */ +sbintime_t tick_sbt; +int maxusers; /* base tunable */ +int maxproc; /* maximum # of processes */ +int maxprocperuid; /* max # of procs per user */ +int maxfiles; /* sys. wide open files limit */ +int maxfilesperproc; /* per-proc open files limit */ +int msgbufsize; /* size of kernel message buffer */ +int nbuf; +int bio_transient_maxcnt; +int ngroups_max; /* max # groups per process */ +int nswbuf; +pid_t pid_max = PID_MAX; +long maxswzone; /* max swmeta KVA storage */ +long maxbcache; /* max buffer cache KVA storage */ +long maxpipekva; /* Limit on pipe KVA */ +int vm_guest; /* Running as virtual machine guest? */ +u_long maxtsiz; /* max text size */ +u_long dfldsiz; /* initial data size limit */ +u_long maxdsiz; /* max data size */ +u_long dflssiz; /* initial stack size limit */ +u_long maxssiz; /* max stack size */ +u_long sgrowsiz; /* amount to grow stack */ + +SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN, &hz, 0, + "Number of clock ticks per second"); +SYSCTL_INT(_kern, OID_AUTO, nbuf, CTLFLAG_RDTUN, &nbuf, 0, + "Number of buffers in the buffer cache"); +SYSCTL_INT(_kern, OID_AUTO, nswbuf, CTLFLAG_RDTUN, &nswbuf, 0, + "Number of swap buffers"); +SYSCTL_INT(_kern, OID_AUTO, msgbufsize, CTLFLAG_RDTUN, &msgbufsize, 0, + "Size of the kernel message buffer"); +SYSCTL_LONG(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0, + "Maximum memory for swap metadata"); +SYSCTL_LONG(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN, &maxbcache, 0, + "Maximum value of vfs.maxbufspace"); +SYSCTL_INT(_kern, OID_AUTO, bio_transient_maxcnt, CTLFLAG_RDTUN, + &bio_transient_maxcnt, 0, + "Maximum number of transient BIOs mappings"); +SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RW | CTLFLAG_TUN, &maxtsiz, 0, + "Maximum text size"); +SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RW | CTLFLAG_TUN, &dfldsiz, 0, + "Initial data size limit"); +SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RW | CTLFLAG_TUN, &maxdsiz, 0, + "Maximum data size"); +SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RW | CTLFLAG_TUN, &dflssiz, 0, + "Initial stack size limit"); +SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RW | CTLFLAG_TUN, &maxssiz, 0, + "Maximum stack size"); +SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RW | CTLFLAG_TUN, &sgrowsiz, 0, + "Amount to grow stack on a stack fault"); +SYSCTL_PROC(_kern, OID_AUTO, vm_guest, CTLFLAG_RD | CTLTYPE_STRING, + NULL, 0, sysctl_kern_vm_guest, "A", + "Virtual machine guest detected? (none|generic|xen)"); + +/* + * These have to be allocated somewhere; allocating + * them here forces loader errors if this file is omitted + * (if they've been externed everywhere else; hah!). + */ +struct buf *swbuf; + +/* + * The elements of this array are ordered based upon the values of the + * corresponding enum VM_GUEST members. + */ +static const char *const vm_guest_sysctl_names[] = { + "none", + "generic", + "xen", + NULL +}; + +#ifndef XEN +static const char *const vm_bnames[] = { + "QEMU", /* QEMU */ + "Plex86", /* Plex86 */ + "Bochs", /* Bochs */ + "Xen", /* Xen */ + "BHYVE", /* bhyve */ + "Seabios", /* KVM */ + NULL +}; + +static const char *const vm_pnames[] = { + "VMware Virtual Platform", /* VMWare VM */ + "Virtual Machine", /* Microsoft VirtualPC */ + "VirtualBox", /* Sun xVM VirtualBox */ + "Parallels Virtual Platform", /* Parallels VM */ + "KVM", /* KVM */ + NULL +}; + + +/* + * Detect known Virtual Machine hosts by inspecting the emulated BIOS. + */ +static enum VM_GUEST +detect_virtual(void) +{ + char *sysenv; + int i; + + sysenv = getenv("smbios.bios.vendor"); + if (sysenv != NULL) { + for (i = 0; vm_bnames[i] != NULL; i++) + if (strcmp(sysenv, vm_bnames[i]) == 0) { + freeenv(sysenv); + return (VM_GUEST_VM); + } + freeenv(sysenv); + } + sysenv = getenv("smbios.system.product"); + if (sysenv != NULL) { + for (i = 0; vm_pnames[i] != NULL; i++) + if (strcmp(sysenv, vm_pnames[i]) == 0) { + freeenv(sysenv); + return (VM_GUEST_VM); + } + freeenv(sysenv); + } + return (VM_GUEST_NO); +} +#endif + +/* + * Boot time overrides that are not scaled against main memory + */ +void +init_param1(void) +{ +#ifndef XEN + vm_guest = detect_virtual(); +#else + vm_guest = VM_GUEST_XEN; +#endif + hz = -1; + TUNABLE_INT_FETCH("kern.hz", &hz); + if (hz == -1) + hz = vm_guest > VM_GUEST_NO ? HZ_VM : HZ; + tick = 1000000 / hz; + tick_sbt = SBT_1S / hz; + tick_bt = sbttobt(tick_sbt); + +#ifdef VM_SWZONE_SIZE_MAX + maxswzone = VM_SWZONE_SIZE_MAX; +#endif + TUNABLE_LONG_FETCH("kern.maxswzone", &maxswzone); +#ifdef VM_BCACHE_SIZE_MAX + maxbcache = VM_BCACHE_SIZE_MAX; +#endif + TUNABLE_LONG_FETCH("kern.maxbcache", &maxbcache); + msgbufsize = MSGBUF_SIZE; + TUNABLE_INT_FETCH("kern.msgbufsize", &msgbufsize); + + maxtsiz = MAXTSIZ; + TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz); + dfldsiz = DFLDSIZ; + TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz); + maxdsiz = MAXDSIZ; + TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz); + dflssiz = DFLSSIZ; + TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz); + maxssiz = MAXSSIZ; + TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz); + sgrowsiz = SGROWSIZ; + TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz); + + /* + * Let the administrator set {NGROUPS_MAX}, but disallow values + * less than NGROUPS_MAX which would violate POSIX.1-2008 or + * greater than INT_MAX-1 which would result in overflow. + */ + ngroups_max = NGROUPS_MAX; + TUNABLE_INT_FETCH("kern.ngroups", &ngroups_max); + if (ngroups_max < NGROUPS_MAX) + ngroups_max = NGROUPS_MAX; + + /* + * Only allow to lower the maximal pid. + * Prevent setting up a non-bootable system if pid_max is too low. + */ + TUNABLE_INT_FETCH("kern.pid_max", &pid_max); + if (pid_max > PID_MAX) + pid_max = PID_MAX; + else if (pid_max < 300) + pid_max = 300; + + TUNABLE_INT_FETCH("vfs.unmapped_buf_allowed", &unmapped_buf_allowed); +} + +/* + * Boot time overrides that are scaled against main memory + */ +void +init_param2(long physpages) +{ + + /* Base parameters */ + maxusers = MAXUSERS; + TUNABLE_INT_FETCH("kern.maxusers", &maxusers); + if (maxusers == 0) { + maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE); + if (maxusers < 32) + maxusers = 32; +#ifdef VM_MAX_AUTOTUNE_MAXUSERS + if (maxusers > VM_MAX_AUTOTUNE_MAXUSERS) + maxusers = VM_MAX_AUTOTUNE_MAXUSERS; +#endif + /* + * Scales down the function in which maxusers grows once + * we hit 384. + */ + if (maxusers > 384) + maxusers = 384 + ((maxusers - 384) / 8); + } + + /* + * The following can be overridden after boot via sysctl. Note: + * unless overriden, these macros are ultimately based on maxusers. + * Limit maxproc so that kmap entries cannot be exhausted by + * processes. + */ + maxproc = NPROC; + TUNABLE_INT_FETCH("kern.maxproc", &maxproc); + if (maxproc > (physpages / 12)) + maxproc = physpages / 12; + maxprocperuid = (maxproc * 9) / 10; + + /* + * The default limit for maxfiles is 1/12 of the number of + * physical page but not less than 16 times maxusers. + * At most it can be 1/6 the number of physical pages. + */ + maxfiles = imax(MAXFILES, physpages / 8); + TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles); + if (maxfiles > (physpages / 4)) + maxfiles = physpages / 4; + maxfilesperproc = (maxfiles / 10) * 9; + + /* + * Cannot be changed after boot. + */ + nbuf = NBUF; + TUNABLE_INT_FETCH("kern.nbuf", &nbuf); + TUNABLE_INT_FETCH("kern.bio_transient_maxcnt", &bio_transient_maxcnt); + + /* + * The default for maxpipekva is min(1/64 of the kernel address space, + * max(1/64 of main memory, 512KB)). See sys_pipe.c for more details. + */ + maxpipekva = (physpages / 64) * PAGE_SIZE; + TUNABLE_LONG_FETCH("kern.ipc.maxpipekva", &maxpipekva); + if (maxpipekva < 512 * 1024) + maxpipekva = 512 * 1024; + if (maxpipekva > (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / 64) + maxpipekva = (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / + 64; +} + +/* + * Sysctl stringiying handler for kern.vm_guest. + */ +static int +sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS) +{ + return (SYSCTL_OUT(req, vm_guest_sysctl_names[vm_guest], + strlen(vm_guest_sysctl_names[vm_guest]))); +} |
