freebsd-dev/sys/kern/init_main.c
David Greenman eadf9e27cd These changes fix a couple of lingering VM problems:
1.	The pageout daemon used to block under certain
	circumstances, and we needed to add new functionality
	that would cause the pageout daemon to block more often.
	Now, the pageout daemon mostly just gets rid of pages
	and kills processes when the system is out of swap.
	The swapping, rss limiting and object cache trimming
	have been folded into a new daemon called "vmdaemon".
	This new daemon does things that need to be done for
	the VM system, but can block.  For example, if the
	vmdaemon blocks for memory, the pageout daemon
	can take care of it.  If the pageout daemon had
	blocked for memory, it was difficult to handle
	the situation correctly (and in some cases, was
	impossible).

2.	The collapse problem has now been entirely fixed.
	It now appears to be impossible to accumulate unnecessary
	vm objects.  The object collapsing now occurs when ref counts
	drop to one (where it is more likely to be more simple anyway
	because less pages would be out on disk.)  The original
	fixes were incomplete in that pathological circumstances
	could still be contrived to cause uncontrolled growth
	of swap.  Also, the old code still, under steady state
	conditions, used more swap space than necessary.  When
	using the new code, users will generally notice a
	significant decrease in swap space usage, and theoretically,
	the system should be leaving fewer unused pages around
	competing for memory.

Submitted by:	John Dyson
1994-11-25 07:58:29 +00:00

456 lines
12 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1991, 1992, 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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.
*
* @(#)init_main.c 8.9 (Berkeley) 1/21/94
* $Id: init_main.c,v 1.16 1994/11/06 05:01:58 davidg Exp $
*/
#include <sys/param.h>
#include <sys/filedesc.h>
#include <sys/errno.h>
#include <sys/exec.h>
#include <sys/kernel.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <sys/sysent.h>
#include <sys/conf.h>
#include <sys/buf.h>
#include <sys/clist.h>
#include <sys/device.h>
#include <sys/protosw.h>
#include <sys/reboot.h>
#include <sys/user.h>
#include <ufs/ufs/quota.h>
#include <machine/cpu.h>
#include <vm/vm.h>
#ifdef HPFPLIB
char copyright[] =
"Copyright (c) 1982, 1986, 1989, 1991, 1993\n\tThe Regents of the University of California.\nCopyright (c) 1992 Hewlett-Packard Company\nCopyright (c) 1992 Motorola Inc.\nAll rights reserved.\n\n";
#else
char copyright[] =
"Copyright (c) 1982, 1986, 1989, 1991, 1993\n\tThe Regents of the University of California. All rights reserved.\n\n";
#endif
/* Components of the first process -- never freed. */
struct session session0;
struct pgrp pgrp0;
struct proc proc0;
struct pcred cred0;
struct filedesc0 filedesc0;
struct plimit limit0;
struct vmspace vmspace0;
struct proc *curproc = &proc0;
struct proc *initproc, *pageproc, *updateproc, *vmproc;
int cmask = CMASK;
extern struct user *proc0paddr;
struct vnode *rootvp, *swapdev_vp;
int boothowto;
struct timeval boottime;
struct timeval runtime;
static void start_init __P((struct proc *p, void *framep));
#if __GNUC__ >= 2
void __main() {}
#endif
/*
* This table is filled in by the linker with functions that need to be
* called to initialize various pseudo-devices and whatnot.
*/
static void dummyinit() {}
TEXT_SET(pseudo_set, dummyinit);
typedef void (*pseudo_func_t)(void);
extern const struct linker_set pseudo_set;
static const pseudo_func_t *pseudos =
(const pseudo_func_t *)&pseudo_set.ls_items[0];
/*
* System startup; initialize the world, create process 0, mount root
* filesystem, and fork to create init and pagedaemon. Most of the
* hard work is done in the lower-level initialization routines including
* startup(), which does memory initialization and autoconfiguration.
*/
void
main(framep)
void *framep;
{
register struct proc *p;
register struct filedesc0 *fdp;
register int i;
int s, rval[2];
extern int (*mountroot) __P((void));
extern void roundrobin __P((void *));
extern void schedcpu __P((void *));
extern struct sysentvec aout_sysvec;
/*
* Initialize the current process pointer (curproc) before
* any possible traps/probes to simplify trap processing.
*/
p = &proc0;
curproc = p;
printf(copyright);
vm_mem_init();
kmeminit();
cpu_startup();
/*
* Create process 0 (the swapper).
*/
allproc = (volatile struct proc *)p;
p->p_prev = (struct proc **)&allproc;
p->p_pgrp = &pgrp0;
pgrphash[0] = &pgrp0;
pgrp0.pg_mem = p;
pgrp0.pg_session = &session0;
session0.s_count = 1;
session0.s_leader = p;
p->p_sysent = &aout_sysvec;
p->p_flag = P_INMEM | P_SYSTEM;
p->p_stat = SRUN;
p->p_nice = NZERO;
p->p_rtprio.type = RTP_PRIO_NORMAL;
p->p_rtprio.prio = 0;
bcopy("swapper", p->p_comm, sizeof ("swapper"));
/* Create credentials. */
cred0.p_refcnt = 1;
p->p_cred = &cred0;
p->p_ucred = crget();
p->p_ucred->cr_ngroups = 1; /* group 0 */
/* Create the file descriptor table. */
fdp = &filedesc0;
p->p_fd = &fdp->fd_fd;
fdp->fd_fd.fd_refcnt = 1;
fdp->fd_fd.fd_cmask = cmask;
fdp->fd_fd.fd_ofiles = fdp->fd_dfiles;
fdp->fd_fd.fd_ofileflags = fdp->fd_dfileflags;
fdp->fd_fd.fd_nfiles = NDFILE;
/* Create the limits structures. */
p->p_limit = &limit0;
for (i = 0; i < sizeof(p->p_rlimit)/sizeof(p->p_rlimit[0]); i++)
limit0.pl_rlimit[i].rlim_cur =
limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY;
limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur = NOFILE;
limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur = MAXUPRC;
i = ptoa(cnt.v_free_count);
limit0.pl_rlimit[RLIMIT_RSS].rlim_max = i;
limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = i;
limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = i / 3;
limit0.p_refcnt = 1;
/* Allocate a prototype map so we have something to fork. */
p->p_vmspace = &vmspace0;
vmspace0.vm_refcnt = 1;
pmap_pinit(&vmspace0.vm_pmap);
vm_map_init(&vmspace0.vm_map, round_page(VM_MIN_ADDRESS),
trunc_page(VM_MAX_ADDRESS), TRUE);
vmspace0.vm_map.pmap = &vmspace0.vm_pmap;
p->p_addr = proc0paddr; /* XXX */
/*
* We continue to place resource usage info and signal
* actions in the user struct so they're pageable.
*/
p->p_stats = &p->p_addr->u_stats;
p->p_sigacts = &p->p_addr->u_sigacts;
/*
* Initialize per uid information structure and charge
* root for one process.
*/
usrinfoinit();
(void)chgproccnt(0, 1);
rqinit();
/* Configure virtual memory system, set vm rlimits. */
vm_init_limits(p);
/* Initialize the file systems. */
vfsinit();
/* Start real time and statistics clocks. */
initclocks();
/* Initialize mbuf's. */
mbinit();
/* Initialize clists. */
clist_init();
#ifdef SYSVSHM
/* Initialize System V style shared memory. */
shminit();
#endif
#ifdef SYSVSEM
/* Initialize System V style semaphores. */
seminit();
#endif
#ifdef SYSVMSG
/* Initialize System V style message queues. */
msginit();
#endif
/*
* Attach pseudo-devices.
*/
while(*pseudos) {
(**pseudos++)();
}
/*
* Initialize protocols. Block reception of incoming packets
* until everything is ready.
*/
s = splimp();
ifinit();
domaininit();
splx(s);
#ifdef GPROF
/* Initialize kernel profiling. */
kmstartup();
#endif
/* Kick off timeout driven events by calling first time. */
roundrobin(NULL);
schedcpu(NULL);
/* Mount the root file system. */
if ((*mountroot)())
panic("cannot mount root");
/* Get the vnode for '/'. Set fdp->fd_fd.fd_cdir to reference it. */
if (VFS_ROOT(mountlist.tqh_first, &rootvnode))
panic("cannot find root vnode");
fdp->fd_fd.fd_cdir = rootvnode;
VREF(fdp->fd_fd.fd_cdir);
VOP_UNLOCK(rootvnode);
fdp->fd_fd.fd_rdir = NULL;
swapinit();
/*
* Now can look at time, having had a chance to verify the time
* from the file system. Reset p->p_rtime as it may have been
* munched in mi_switch() after the time got set.
*/
p->p_stats->p_start = runtime = mono_time = boottime = time;
p->p_rtime.tv_sec = p->p_rtime.tv_usec = 0;
/* Initialize signal state for process 0. */
siginit(p);
/* Create process 1 (init(8)). */
if (fork(p, NULL, rval))
panic("fork init");
if (rval[1]) {
start_init(curproc, framep);
return;
}
/* Create process 2 (the pageout daemon). */
if (fork(p, NULL, rval))
panic("fork pager");
if (rval[1]) {
/*
* Now in process 2.
*/
p = curproc;
pageproc = p;
p->p_flag |= P_INMEM | P_SYSTEM; /* XXX */
bcopy("pagedaemon", curproc->p_comm, sizeof ("pagedaemon"));
vm_pageout();
/* NOTREACHED */
}
/*
* Start high level vm daemon (process 3).
*/
if (fork(p, (void *) NULL, rval))
panic("failed fork vm daemon");
if (rval[1]) {
p = curproc;
vmproc = p;
p->p_flag |= P_INMEM | P_SYSTEM;
bcopy("vmdaemon", p->p_comm, sizeof("vmdaemon"));
vm_daemon();
/*NOTREACHED*/
}
/*
* Start update daemon (process 4).
*/
if (fork(p, (void *) NULL, rval))
panic("failed fork update daemon");
if (rval[1]) {
p = curproc;
updateproc = p;
p->p_flag |= P_INMEM | P_SYSTEM;
bcopy("update", p->p_comm, sizeof("update"));
vfs_update();
/*NOTREACHED*/
}
/* The scheduler is an infinite loop. */
scheduler();
/* NOTREACHED */
}
/*
* List of paths to try when searching for "init".
*/
static char *initpaths[] = {
"/sbin/init",
"/sbin/oinit",
"/sbin/init.bak",
"/stand/sysinstall",
NULL,
};
/*
* Start the initial user process; try exec'ing each pathname in "initpaths".
* The program is invoked with one argument containing the boot flags.
*/
static void
start_init(p, framep)
struct proc *p;
void *framep;
{
vm_offset_t addr;
struct execve_args args;
int options, i, retval[2], error;
char **pathp, *path, *ucp, **uap, *arg0, *arg1;
initproc = p;
/*
* We need to set the system call frame as if we were entered through
* a syscall() so that when we call execve() below, it will be able
* to set the entry point (see setregs) when it tries to exec. The
* startup code in "locore.s" has allocated space for the frame and
* passed a pointer to that space as main's argument.
*/
cpu_set_init_frame(p, framep);
/*
* Need just enough stack to hold the faked-up "execve()" arguments.
*/
addr = trunc_page(VM_MAXUSER_ADDRESS - PAGE_SIZE);
if (vm_allocate(&p->p_vmspace->vm_map, &addr, PAGE_SIZE, FALSE) != 0)
panic("init: couldn't allocate argument space");
p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
p->p_vmspace->vm_ssize = 1;
for (pathp = &initpaths[0]; (path = *pathp) != NULL; pathp++) {
/*
* Move out the boot flag argument.
*/
options = 0;
ucp = (char *)USRSTACK;
(void)subyte(--ucp, 0); /* trailing zero */
if (boothowto & RB_SINGLE) {
(void)subyte(--ucp, 's');
options = 1;
}
#ifdef notyet
if (boothowto & RB_FASTBOOT) {
(void)subyte(--ucp, 'f');
options = 1;
}
#endif
if (options == 0)
(void)subyte(--ucp, '-');
(void)subyte(--ucp, '-'); /* leading hyphen */
arg1 = ucp;
/*
* Move out the file name (also arg 0).
*/
for (i = strlen(path) + 1; i >= 0; i--)
(void)subyte(--ucp, path[i]);
arg0 = ucp;
/*
* Move out the arg pointers.
*/
uap = (char **)((int)ucp & ~(NBPW-1));
(void)suword((caddr_t)--uap, 0); /* terminator */
(void)suword((caddr_t)--uap, (int)arg1);
(void)suword((caddr_t)--uap, (int)arg0);
/*
* Point at the arguments.
*/
args.fname = arg0;
args.argv = uap;
args.envv = NULL;
/*
* Now try to exec the program. If can't for any reason
* other than it doesn't exist, complain.
*/
if ((error = execve(p, &args, &retval)) == 0)
return;
if (error != ENOENT)
printf("exec %s: error %d\n", path, error);
}
printf("init: not found\n");
panic("no init");
}