Fix typo (unbreaks LINT build).
[dragonfly.git] / sys / kern / kern_shutdown.c
blob015c8e19e8ea7882ebbb237df0bc77ef32674208
1 /*-
2 * Copyright (c) 1986, 1988, 1991, 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.
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 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
38 * @(#)kern_shutdown.c 8.3 (Berkeley) 1/21/94
39 * $FreeBSD: src/sys/kern/kern_shutdown.c,v 1.72.2.12 2002/02/21 19:15:10 dillon Exp $
40 * $DragonFly: src/sys/kern/kern_shutdown.c,v 1.62 2008/01/05 13:23:48 corecode Exp $
43 #include "opt_ddb.h"
44 #include "opt_ddb_trace.h"
45 #include "opt_hw_wdog.h"
46 #include "opt_panic.h"
47 #include "opt_show_busybufs.h"
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/eventhandler.h>
52 #include <sys/buf.h>
53 #include <sys/diskslice.h>
54 #include <sys/reboot.h>
55 #include <sys/proc.h>
56 #include <sys/priv.h>
57 #include <sys/fcntl.h> /* FREAD */
58 #include <sys/stat.h> /* S_IFCHR */
59 #include <sys/vnode.h>
60 #include <sys/kernel.h>
61 #include <sys/kthread.h>
62 #include <sys/malloc.h>
63 #include <sys/mount.h>
64 #include <sys/queue.h>
65 #include <sys/sysctl.h>
66 #include <sys/vkernel.h>
67 #include <sys/conf.h>
68 #include <sys/sysproto.h>
69 #include <sys/device.h>
70 #include <sys/cons.h>
71 #include <sys/shm.h>
72 #include <sys/kern_syscall.h>
73 #include <vm/vm_map.h>
74 #include <vm/pmap.h>
76 #include <sys/thread2.h>
77 #include <sys/buf2.h>
79 #include <machine/pcb.h>
80 #include <machine/clock.h>
81 #include <machine/md_var.h>
82 #include <machine/smp.h> /* smp_active_mask, cpuid */
83 #include <machine/vmparam.h>
85 #include <sys/signalvar.h>
87 #ifndef PANIC_REBOOT_WAIT_TIME
88 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
89 #endif
92 * Note that stdarg.h and the ANSI style va_start macro is used for both
93 * ANSI and traditional C compilers. We use the machine version to stay
94 * within the confines of the kernel header files.
96 #include <machine/stdarg.h>
98 #ifdef DDB
99 #ifdef DDB_UNATTENDED
100 int debugger_on_panic = 0;
101 #else
102 int debugger_on_panic = 1;
103 #endif
104 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
105 &debugger_on_panic, 0, "Run debugger on kernel panic");
107 extern void db_print_backtrace(void);
109 #ifdef DDB_TRACE
110 int trace_on_panic = 1;
111 #else
112 int trace_on_panic = 0;
113 #endif
114 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW,
115 &trace_on_panic, 0, "Print stack trace on kernel panic");
116 #endif
118 static int sync_on_panic = 1;
119 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW,
120 &sync_on_panic, 0, "Do a sync before rebooting from a panic");
122 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment");
124 #ifdef HW_WDOG
126 * If there is a hardware watchdog, point this at the function needed to
127 * hold it off.
128 * It's needed when the kernel needs to do some lengthy operations.
129 * e.g. in wd.c when dumping core.. It's most annoying to have
130 * your precious core-dump only half written because the wdog kicked in.
132 watchdog_tickle_fn wdog_tickler = NULL;
133 #endif /* HW_WDOG */
136 * Variable panicstr contains argument to first call to panic; used as flag
137 * to indicate that the kernel has already called panic.
139 const char *panicstr;
141 int dumping; /* system is dumping */
142 #ifdef SMP
143 u_int panic_cpu_interlock; /* panic interlock */
144 globaldata_t panic_cpu_gd; /* which cpu took the panic */
145 #endif
147 int bootverbose = 0; /* note: assignment to force non-bss */
148 SYSCTL_INT(_debug, OID_AUTO, bootverbose, CTLFLAG_RW,
149 &bootverbose, 0, "Verbose kernel messages");
151 int cold = 1; /* note: assignment to force non-bss */
152 int dumplo; /* OBSOLETE - savecore compat */
153 u_int64_t dumplo64;
155 static void boot (int) __dead2;
156 static void dumpsys (void);
157 static int setdumpdev (cdev_t dev);
158 static void poweroff_wait (void *, int);
159 static void print_uptime (void);
160 static void shutdown_halt (void *junk, int howto);
161 static void shutdown_panic (void *junk, int howto);
162 static void shutdown_reset (void *junk, int howto);
163 static int shutdown_busycount1(struct buf *bp, void *info);
164 static int shutdown_busycount2(struct buf *bp, void *info);
165 static void shutdown_cleanup_proc(struct proc *p);
167 /* register various local shutdown events */
168 static void
169 shutdown_conf(void *unused)
171 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, SHUTDOWN_PRI_FIRST);
172 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, SHUTDOWN_PRI_LAST + 100);
173 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, SHUTDOWN_PRI_LAST + 100);
174 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, SHUTDOWN_PRI_LAST + 200);
177 SYSINIT(shutdown_conf, SI_BOOT2_MACHDEP, SI_ORDER_ANY, shutdown_conf, NULL)
179 /* ARGSUSED */
182 * The system call that results in a reboot
185 sys_reboot(struct reboot_args *uap)
187 struct thread *td = curthread;
188 int error;
190 if ((error = priv_check(td, PRIV_ROOT)))
191 return (error);
193 boot(uap->opt);
194 return (0);
198 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC
200 static int shutdown_howto = 0;
202 void
203 shutdown_nice(int howto)
205 shutdown_howto = howto;
207 /* Send a signal to init(8) and have it shutdown the world */
208 if (initproc != NULL) {
209 ksignal(initproc, SIGINT);
210 } else {
211 /* No init(8) running, so simply reboot */
212 boot(RB_NOSYNC);
214 return;
216 static int waittime = -1;
217 static struct thread *dumpthread;
218 static struct pcb dumppcb;
220 static void
221 print_uptime(void)
223 int f;
224 struct timespec ts;
226 getnanouptime(&ts);
227 kprintf("Uptime: ");
228 f = 0;
229 if (ts.tv_sec >= 86400) {
230 kprintf("%ldd", ts.tv_sec / 86400);
231 ts.tv_sec %= 86400;
232 f = 1;
234 if (f || ts.tv_sec >= 3600) {
235 kprintf("%ldh", ts.tv_sec / 3600);
236 ts.tv_sec %= 3600;
237 f = 1;
239 if (f || ts.tv_sec >= 60) {
240 kprintf("%ldm", ts.tv_sec / 60);
241 ts.tv_sec %= 60;
242 f = 1;
244 kprintf("%lds\n", ts.tv_sec);
248 * Go through the rigmarole of shutting down..
249 * this used to be in machdep.c but I'll be dammned if I could see
250 * anything machine dependant in it.
252 static void
253 boot(int howto)
256 * Get rid of any user scheduler baggage and then give
257 * us a high priority.
259 if (curthread->td_release)
260 curthread->td_release(curthread);
261 lwkt_setpri_self(TDPRI_MAX);
263 /* collect extra flags that shutdown_nice might have set */
264 howto |= shutdown_howto;
266 #ifdef SMP
268 * We really want to shutdown on the BSP. Subsystems such as ACPI
269 * can't power-down the box otherwise.
271 if (smp_active_mask > 1) {
272 kprintf("boot() called on cpu#%d\n", mycpu->gd_cpuid);
274 if (panicstr == NULL && mycpu->gd_cpuid != 0) {
275 kprintf("Switching to cpu #0 for shutdown\n");
276 lwkt_setcpu_self(globaldata_find(0));
278 #endif
280 * Do any callouts that should be done BEFORE syncing the filesystems.
282 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
285 * Try to get rid of any remaining FS references. The calling
286 * process, proc0, and init may still hold references. The
287 * VFS cache subsystem may still hold a root reference to root.
289 * XXX this needs work. We really need to SIGSTOP all remaining
290 * processes in order to avoid blowups due to proc0's filesystem
291 * references going away. For now just make sure that the init
292 * process is stopped.
294 if (panicstr == NULL) {
295 shutdown_cleanup_proc(curproc);
296 shutdown_cleanup_proc(&proc0);
297 if (initproc) {
298 if (initproc != curproc) {
299 ksignal(initproc, SIGSTOP);
300 tsleep(boot, 0, "shutdn", hz / 20);
302 shutdown_cleanup_proc(initproc);
304 vfs_cache_setroot(NULL, NULL);
308 * Now sync filesystems
310 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
311 int iter, nbusy, pbusy;
313 waittime = 0;
314 kprintf("\nsyncing disks... ");
316 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */
319 * With soft updates, some buffers that are
320 * written will be remarked as dirty until other
321 * buffers are written.
323 for (iter = pbusy = 0; iter < 20; iter++) {
324 nbusy = scan_all_buffers(shutdown_busycount1, NULL);
325 if (nbusy == 0)
326 break;
327 kprintf("%d ", nbusy);
328 if (nbusy < pbusy)
329 iter = 0;
330 pbusy = nbusy;
332 * XXX:
333 * Process soft update work queue if buffers don't sync
334 * after 6 iterations by permitting the syncer to run.
336 if (iter > 5)
337 bio_ops_sync(NULL);
339 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */
340 tsleep(boot, 0, "shutdn", hz * iter / 20 + 1);
342 kprintf("\n");
344 * Count only busy local buffers to prevent forcing
345 * a fsck if we're just a client of a wedged NFS server
347 nbusy = scan_all_buffers(shutdown_busycount2, NULL);
348 if (nbusy) {
350 * Failed to sync all blocks. Indicate this and don't
351 * unmount filesystems (thus forcing an fsck on reboot).
353 kprintf("giving up on %d buffers\n", nbusy);
354 #ifdef DDB
355 Debugger("busy buffer problem");
356 #endif /* DDB */
357 tsleep(boot, 0, "shutdn", hz * 5 + 1);
358 } else {
359 kprintf("done\n");
361 * Unmount filesystems
363 if (panicstr == NULL)
364 vfs_unmountall();
366 tsleep(boot, 0, "shutdn", hz / 10 + 1);
369 print_uptime();
372 * Dump before doing post_sync shutdown ops
374 crit_enter();
375 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold)
376 dumpsys();
379 * Ok, now do things that assume all filesystem activity has
380 * been completed. This will also call the device shutdown
381 * methods.
383 EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
385 /* Now that we're going to really halt the system... */
386 EVENTHANDLER_INVOKE(shutdown_final, howto);
388 for(;;) ; /* safety against shutdown_reset not working */
389 /* NOTREACHED */
392 static int
393 shutdown_busycount1(struct buf *bp, void *info)
395 if ((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp) > 0)
396 return(1);
397 if ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI)
398 return (1);
399 return (0);
402 static int
403 shutdown_busycount2(struct buf *bp, void *info)
405 if (((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp)) ||
406 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) {
408 * Only count buffers undergoing write I/O
409 * on the related vnode.
411 if (bp->b_vp == NULL ||
412 bp->b_vp->v_track_write.bk_active == 0) {
413 return (0);
415 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC)
416 kprintf(
417 "%p dev:?, flags:%08x, loffset:%lld, doffset:%lld\n",
418 bp,
419 bp->b_flags, bp->b_loffset,
420 bp->b_bio2.bio_offset);
421 #endif
422 return(1);
424 return(0);
428 * If the shutdown was a clean halt, behave accordingly.
430 static void
431 shutdown_halt(void *junk, int howto)
433 if (howto & RB_HALT) {
434 kprintf("\n");
435 kprintf("The operating system has halted.\n");
436 #ifdef _KERNEL_VIRTUAL
437 cpu_halt();
438 #else
439 kprintf("Please press any key to reboot.\n\n");
440 switch (cngetc()) {
441 case -1: /* No console, just die */
442 cpu_halt();
443 /* NOTREACHED */
444 default:
445 howto &= ~RB_HALT;
446 break;
448 #endif
453 * Check to see if the system paniced, pause and then reboot
454 * according to the specified delay.
456 static void
457 shutdown_panic(void *junk, int howto)
459 int loop;
461 if (howto & RB_DUMP) {
462 if (PANIC_REBOOT_WAIT_TIME != 0) {
463 if (PANIC_REBOOT_WAIT_TIME != -1) {
464 kprintf("Automatic reboot in %d seconds - "
465 "press a key on the console to abort\n",
466 PANIC_REBOOT_WAIT_TIME);
467 for (loop = PANIC_REBOOT_WAIT_TIME * 10;
468 loop > 0; --loop) {
469 DELAY(1000 * 100); /* 1/10th second */
470 /* Did user type a key? */
471 if (cncheckc() != -1)
472 break;
474 if (!loop)
475 return;
477 } else { /* zero time specified - reboot NOW */
478 return;
480 kprintf("--> Press a key on the console to reboot,\n");
481 kprintf("--> or switch off the system now.\n");
482 cngetc();
487 * Everything done, now reset
489 static void
490 shutdown_reset(void *junk, int howto)
492 kprintf("Rebooting...\n");
493 DELAY(1000000); /* wait 1 sec for kprintf's to complete and be read */
494 /* cpu_boot(howto); */ /* doesn't do anything at the moment */
495 cpu_reset();
496 /* NOTREACHED */ /* assuming reset worked */
500 * Try to remove FS references in the specified process. This function
501 * is used during shutdown
503 static
504 void
505 shutdown_cleanup_proc(struct proc *p)
507 struct filedesc *fdp;
508 struct vmspace *vm;
510 if (p == NULL)
511 return;
512 if ((fdp = p->p_fd) != NULL) {
513 kern_closefrom(0);
514 if (fdp->fd_cdir) {
515 cache_drop(&fdp->fd_ncdir);
516 vrele(fdp->fd_cdir);
517 fdp->fd_cdir = NULL;
519 if (fdp->fd_rdir) {
520 cache_drop(&fdp->fd_nrdir);
521 vrele(fdp->fd_rdir);
522 fdp->fd_rdir = NULL;
524 if (fdp->fd_jdir) {
525 cache_drop(&fdp->fd_njdir);
526 vrele(fdp->fd_jdir);
527 fdp->fd_jdir = NULL;
530 if (p->p_vkernel)
531 vkernel_exit(p);
532 if (p->p_textvp) {
533 vrele(p->p_textvp);
534 p->p_textvp = NULL;
536 vm = p->p_vmspace;
537 if (vm != NULL) {
538 pmap_remove_pages(vmspace_pmap(vm),
539 VM_MIN_USER_ADDRESS,
540 VM_MAX_USER_ADDRESS);
541 vm_map_remove(&vm->vm_map,
542 VM_MIN_USER_ADDRESS,
543 VM_MAX_USER_ADDRESS);
548 * Magic number for savecore
550 * exported (symorder) and used at least by savecore(8)
552 * Mark it as used so that gcc doesn't optimize it away.
554 __attribute__((__used__))
555 static u_long const dumpmag = 0x8fca0101UL;
557 static int dumpsize = 0; /* also for savecore */
559 static int dodump = 1;
561 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0,
562 "Try to perform coredump on kernel panic");
564 static int
565 setdumpdev(cdev_t dev)
567 struct partinfo pinfo;
568 u_int64_t newdumplo;
569 int error;
570 int doopen;
572 if (dev == NULL) {
573 dumpdev = dev;
574 return (0);
576 bzero(&pinfo, sizeof(pinfo));
579 * We have to open the device before we can perform ioctls on it,
580 * or the slice/label data may not be present. Device opens are
581 * usually tracked by specfs, but the dump device can be set in
582 * early boot and may not be open so this is somewhat of a hack.
584 doopen = (dev->si_sysref.refcnt == 1);
585 if (doopen) {
586 error = dev_dopen(dev, FREAD, S_IFCHR, proc0.p_ucred);
587 if (error)
588 return (error);
590 error = dev_dioctl(dev, DIOCGPART, (void *)&pinfo, 0, proc0.p_ucred);
591 if (doopen)
592 dev_dclose(dev, FREAD, S_IFCHR);
593 if (error || pinfo.media_blocks == 0 || pinfo.media_blksize == 0)
594 return (ENXIO);
596 newdumplo = pinfo.media_blocks -
597 ((u_int64_t)Maxmem * PAGE_SIZE / DEV_BSIZE);
598 if ((int64_t)newdumplo < (int64_t)pinfo.reserved_blocks)
599 return (ENOSPC);
600 dumpdev = dev;
601 dumplo64 = newdumplo;
602 return (0);
606 /* ARGSUSED */
607 static void dump_conf (void *dummy);
608 static void
609 dump_conf(void *dummy)
611 char *path;
612 cdev_t dev;
614 path = kmalloc(MNAMELEN, M_TEMP, M_WAITOK);
615 if (TUNABLE_STR_FETCH("dumpdev", path, MNAMELEN) != 0) {
616 dev = kgetdiskbyname(path);
617 if (dev != NULL)
618 dumpdev = dev;
620 kfree(path, M_TEMP);
621 if (setdumpdev(dumpdev) != 0)
622 dumpdev = NULL;
625 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL)
627 static int
628 sysctl_kern_dumpdev(SYSCTL_HANDLER_ARGS)
630 int error;
631 udev_t ndumpdev;
633 ndumpdev = dev2udev(dumpdev);
634 error = sysctl_handle_opaque(oidp, &ndumpdev, sizeof ndumpdev, req);
635 if (error == 0 && req->newptr != NULL)
636 error = setdumpdev(udev2dev(ndumpdev, 0));
637 return (error);
640 SYSCTL_PROC(_kern, KERN_DUMPDEV, dumpdev, CTLTYPE_OPAQUE|CTLFLAG_RW,
641 0, sizeof dumpdev, sysctl_kern_dumpdev, "T,udev_t", "");
644 * Doadump comes here after turning off memory management and
645 * getting on the dump stack, either when called above, or by
646 * the auto-restart code.
648 static void
649 dumpsys(void)
651 int error;
653 savectx(&dumppcb);
654 dumpthread = curthread;
655 if (dumping++) {
656 kprintf("Dump already in progress, bailing...\n");
657 return;
659 if (!dodump)
660 return;
661 if (dumpdev == NULL)
662 return;
663 dumpsize = Maxmem;
664 kprintf("\ndumping to dev %s, blockno %lld\n",
665 devtoname(dumpdev), dumplo64);
666 kprintf("dump ");
667 error = dev_ddump(dumpdev);
668 if (error == 0) {
669 kprintf("succeeded\n");
670 return;
672 kprintf("failed, reason: ");
673 switch (error) {
674 case ENOSYS:
675 case ENODEV:
676 kprintf("device doesn't support a dump routine\n");
677 break;
679 case ENXIO:
680 kprintf("device bad\n");
681 break;
683 case EFAULT:
684 kprintf("device not ready\n");
685 break;
687 case EINVAL:
688 kprintf("area improper\n");
689 break;
691 case EIO:
692 kprintf("i/o error\n");
693 break;
695 case EINTR:
696 kprintf("aborted from console\n");
697 break;
699 default:
700 kprintf("unknown, error = %d\n", error);
701 break;
706 dumpstatus(vm_offset_t addr, off_t count)
708 int c;
710 if (addr % (1024 * 1024) == 0) {
711 #ifdef HW_WDOG
712 if (wdog_tickler)
713 (*wdog_tickler)();
714 #endif
715 kprintf("%ld ", (long)(count / (1024 * 1024)));
718 if ((c = cncheckc()) == 0x03)
719 return -1;
720 else if (c != -1)
721 kprintf("[CTRL-C to abort] ");
723 return 0;
727 * Panic is called on unresolvable fatal errors. It prints "panic: mesg",
728 * and then reboots. If we are called twice, then we avoid trying to sync
729 * the disks as this often leads to recursive panics.
731 void
732 panic(const char *fmt, ...)
734 int bootopt, newpanic;
735 __va_list ap;
736 static char buf[256];
738 #ifdef SMP
740 * If a panic occurs on multiple cpus before the first is able to
741 * halt the other cpus, only one cpu is allowed to take the panic.
742 * Attempt to be verbose about this situation but if the kprintf()
743 * itself panics don't let us overrun the kernel stack.
745 * Be very nasty about descheduling our thread at the lowest
746 * level possible in an attempt to freeze the thread without
747 * inducing further panics.
749 * Bumping gd_trap_nesting_level will also bypass assertions in
750 * lwkt_switch() and allow us to switch away even if we are a
751 * FAST interrupt or IPI.
753 if (atomic_poll_acquire_int(&panic_cpu_interlock)) {
754 panic_cpu_gd = mycpu;
755 } else if (panic_cpu_gd != mycpu) {
756 crit_enter();
757 ++mycpu->gd_trap_nesting_level;
758 if (mycpu->gd_trap_nesting_level < 25) {
759 kprintf("SECONDARY PANIC ON CPU %d THREAD %p\n",
760 mycpu->gd_cpuid, curthread);
762 curthread->td_release = NULL; /* be a grinch */
763 for (;;) {
764 lwkt_deschedule_self(curthread);
765 lwkt_switch();
767 /* NOT REACHED */
768 /* --mycpu->gd_trap_nesting_level */
769 /* crit_exit() */
771 #endif
772 bootopt = RB_AUTOBOOT | RB_DUMP;
773 if (sync_on_panic == 0)
774 bootopt |= RB_NOSYNC;
775 newpanic = 0;
776 if (panicstr)
777 bootopt |= RB_NOSYNC;
778 else {
779 panicstr = fmt;
780 newpanic = 1;
783 __va_start(ap, fmt);
784 kvsnprintf(buf, sizeof(buf), fmt, ap);
785 if (panicstr == fmt)
786 panicstr = buf;
787 __va_end(ap);
788 kprintf("panic: %s\n", buf);
789 #ifdef SMP
790 /* two separate prints in case of an unmapped page and trap */
791 kprintf("mp_lock = %08x; ", mp_lock);
792 kprintf("cpuid = %d\n", mycpu->gd_cpuid);
793 #endif
795 #if defined(DDB)
796 if (newpanic && trace_on_panic)
797 db_print_backtrace();
798 if (debugger_on_panic)
799 Debugger("panic");
800 #endif
801 boot(bootopt);
805 * Support for poweroff delay.
807 #ifndef POWEROFF_DELAY
808 # define POWEROFF_DELAY 5000
809 #endif
810 static int poweroff_delay = POWEROFF_DELAY;
812 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
813 &poweroff_delay, 0, "");
815 static void
816 poweroff_wait(void *junk, int howto)
818 if(!(howto & RB_POWEROFF) || poweroff_delay <= 0)
819 return;
820 DELAY(poweroff_delay * 1000);
824 * Some system processes (e.g. syncer) need to be stopped at appropriate
825 * points in their main loops prior to a system shutdown, so that they
826 * won't interfere with the shutdown process (e.g. by holding a disk buf
827 * to cause sync to fail). For each of these system processes, register
828 * shutdown_kproc() as a handler for one of shutdown events.
830 static int kproc_shutdown_wait = 60;
831 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
832 &kproc_shutdown_wait, 0, "");
834 void
835 shutdown_kproc(void *arg, int howto)
837 struct thread *td;
838 struct proc *p;
839 int error;
841 if (panicstr)
842 return;
844 td = (struct thread *)arg;
845 if ((p = td->td_proc) != NULL) {
846 kprintf("Waiting (max %d seconds) for system process `%s' to stop...",
847 kproc_shutdown_wait, p->p_comm);
848 } else {
849 kprintf("Waiting (max %d seconds) for system thread %s to stop...",
850 kproc_shutdown_wait, td->td_comm);
852 error = suspend_kproc(td, kproc_shutdown_wait * hz);
854 if (error == EWOULDBLOCK)
855 kprintf("timed out\n");
856 else
857 kprintf("stopped\n");