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. 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 * 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. 25 * 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. 37 * 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 1.22 2005/07/19 19:53:53 dillon Exp $ 41 */ 42 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" 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/eventhandler.h> 52 #include <sys/buf.h> 53 #include <sys/disklabel.h> 54 #include <sys/reboot.h> 55 #include <sys/proc.h> 56 #include <sys/vnode.h> 57 #include <sys/kernel.h> 58 #include <sys/kthread.h> 59 #include <sys/malloc.h> 60 #include <sys/mount.h> 61 #include <sys/queue.h> 62 #include <sys/sysctl.h> 63 #include <sys/conf.h> 64 #include <sys/sysproto.h> 65 #include <sys/device.h> 66 #include <sys/cons.h> 67 #include <sys/thread2.h> 68 #include <sys/buf2.h> 69 70 #include <machine/pcb.h> 71 #include <machine/clock.h> 72 #include <machine/md_var.h> 73 #include <machine/smp.h> /* smp_active_mask, cpuid */ 74 75 #include <sys/signalvar.h> 76 77 #ifndef PANIC_REBOOT_WAIT_TIME 78 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 79 #endif 80 81 /* 82 * Note that stdarg.h and the ANSI style va_start macro is used for both 83 * ANSI and traditional C compilers. We use the machine version to stay 84 * within the confines of the kernel header files. 85 */ 86 #include <machine/stdarg.h> 87 88 #ifdef DDB 89 #ifdef DDB_UNATTENDED 90 int debugger_on_panic = 0; 91 #else 92 int debugger_on_panic = 1; 93 #endif 94 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW, 95 &debugger_on_panic, 0, "Run debugger on kernel panic"); 96 97 extern void db_print_backtrace(void); 98 99 #ifdef DDB_TRACE 100 int trace_on_panic = 1; 101 #else 102 int trace_on_panic = 0; 103 #endif 104 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 105 &trace_on_panic, 0, "Print stack trace on kernel panic"); 106 #endif 107 108 static int sync_on_panic = 1; 109 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 110 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 111 112 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 113 114 #ifdef HW_WDOG 115 /* 116 * If there is a hardware watchdog, point this at the function needed to 117 * hold it off. 118 * It's needed when the kernel needs to do some lengthy operations. 119 * e.g. in wd.c when dumping core.. It's most annoying to have 120 * your precious core-dump only half written because the wdog kicked in. 121 */ 122 watchdog_tickle_fn wdog_tickler = NULL; 123 #endif /* HW_WDOG */ 124 125 /* 126 * Variable panicstr contains argument to first call to panic; used as flag 127 * to indicate that the kernel has already called panic. 128 */ 129 const char *panicstr; 130 131 int dumping; /* system is dumping */ 132 #ifdef SMP 133 u_int panic_cpu_interlock; /* panic interlock */ 134 globaldata_t panic_cpu_gd; /* which cpu took the panic */ 135 #endif 136 137 static void boot (int) __dead2; 138 static void dumpsys (void); 139 static int setdumpdev (dev_t dev); 140 static void poweroff_wait (void *, int); 141 static void print_uptime (void); 142 static void shutdown_halt (void *junk, int howto); 143 static void shutdown_panic (void *junk, int howto); 144 static void shutdown_reset (void *junk, int howto); 145 146 /* register various local shutdown events */ 147 static void 148 shutdown_conf(void *unused) 149 { 150 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, SHUTDOWN_PRI_FIRST); 151 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, SHUTDOWN_PRI_LAST + 100); 152 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, SHUTDOWN_PRI_LAST + 100); 153 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, SHUTDOWN_PRI_LAST + 200); 154 } 155 156 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL) 157 158 /* ARGSUSED */ 159 160 /* 161 * The system call that results in a reboot 162 */ 163 int 164 reboot(struct reboot_args *uap) 165 { 166 struct thread *td = curthread; 167 int error; 168 169 if ((error = suser(td))) 170 return (error); 171 172 boot(uap->opt); 173 return (0); 174 } 175 176 /* 177 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 178 */ 179 static int shutdown_howto = 0; 180 181 void 182 shutdown_nice(int howto) 183 { 184 shutdown_howto = howto; 185 186 /* Send a signal to init(8) and have it shutdown the world */ 187 if (initproc != NULL) { 188 psignal(initproc, SIGINT); 189 } else { 190 /* No init(8) running, so simply reboot */ 191 boot(RB_NOSYNC); 192 } 193 return; 194 } 195 static int waittime = -1; 196 static struct pcb dumppcb; 197 198 static void 199 print_uptime() 200 { 201 int f; 202 struct timespec ts; 203 204 getnanouptime(&ts); 205 printf("Uptime: "); 206 f = 0; 207 if (ts.tv_sec >= 86400) { 208 printf("%ldd", ts.tv_sec / 86400); 209 ts.tv_sec %= 86400; 210 f = 1; 211 } 212 if (f || ts.tv_sec >= 3600) { 213 printf("%ldh", ts.tv_sec / 3600); 214 ts.tv_sec %= 3600; 215 f = 1; 216 } 217 if (f || ts.tv_sec >= 60) { 218 printf("%ldm", ts.tv_sec / 60); 219 ts.tv_sec %= 60; 220 f = 1; 221 } 222 printf("%lds\n", ts.tv_sec); 223 } 224 225 /* 226 * Go through the rigmarole of shutting down.. 227 * this used to be in machdep.c but I'll be dammned if I could see 228 * anything machine dependant in it. 229 */ 230 static void 231 boot(int howto) 232 { 233 /* 234 * Get rid of any user scheduler baggage and then give 235 * us a high priority. 236 */ 237 if (curthread->td_release) 238 curthread->td_release(curthread); 239 lwkt_setpri_self(TDPRI_MAX); 240 241 /* collect extra flags that shutdown_nice might have set */ 242 howto |= shutdown_howto; 243 244 #ifdef SMP 245 if (smp_active_mask > 1) { 246 printf("boot() called on cpu#%d\n", mycpu->gd_cpuid); 247 } 248 #endif 249 /* 250 * Do any callouts that should be done BEFORE syncing the filesystems. 251 */ 252 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 253 254 /* 255 * Now sync filesystems 256 */ 257 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 258 struct buf *bp; 259 int iter, nbusy, pbusy; 260 261 waittime = 0; 262 printf("\nsyncing disks... "); 263 264 sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 265 266 /* 267 * With soft updates, some buffers that are 268 * written will be remarked as dirty until other 269 * buffers are written. 270 */ 271 for (iter = pbusy = 0; iter < 20; iter++) { 272 nbusy = 0; 273 for (bp = &buf[nbuf]; --bp >= buf; ) { 274 if ((bp->b_flags & B_INVAL) == 0 && 275 BUF_REFCNT(bp) > 0) { 276 nbusy++; 277 } else if ((bp->b_flags & (B_DELWRI | B_INVAL)) 278 == B_DELWRI) { 279 /* bawrite(bp);*/ 280 nbusy++; 281 } 282 } 283 if (nbusy == 0) 284 break; 285 printf("%d ", nbusy); 286 if (nbusy < pbusy) 287 iter = 0; 288 pbusy = nbusy; 289 /* 290 * XXX: 291 * Process soft update work queue if buffers don't sync 292 * after 6 iterations by permitting the syncer to run. 293 */ 294 if (iter > 5 && bioops.io_sync) 295 (*bioops.io_sync)(NULL); 296 sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 297 tsleep(boot, 0, "shutdn", hz * iter / 20 + 1); 298 } 299 printf("\n"); 300 /* 301 * Count only busy local buffers to prevent forcing 302 * a fsck if we're just a client of a wedged NFS server 303 */ 304 nbusy = 0; 305 for (bp = &buf[nbuf]; --bp >= buf; ) { 306 if (((bp->b_flags&B_INVAL) == 0 && BUF_REFCNT(bp)) || 307 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) { 308 if (bp->b_dev == NODEV) { 309 mountlist_remove(bp->b_vp->v_mount); 310 continue; 311 } 312 nbusy++; 313 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 314 printf( 315 "%p %d: dev:%s, flags:%08lx, blkno:%ld, lblkno:%ld\n", 316 bp, nbusy, devtoname(bp->b_dev), 317 bp->b_flags, (long)bp->b_blkno, 318 (long)bp->b_lblkno); 319 #endif 320 } 321 } 322 if (nbusy) { 323 /* 324 * Failed to sync all blocks. Indicate this and don't 325 * unmount filesystems (thus forcing an fsck on reboot). 326 */ 327 printf("giving up on %d buffers\n", nbusy); 328 #ifdef DDB 329 Debugger("busy buffer problem"); 330 #endif /* DDB */ 331 tsleep(boot, 0, "shutdn", hz * 5 + 1); 332 } else { 333 printf("done\n"); 334 /* 335 * Unmount filesystems 336 */ 337 if (panicstr == 0) 338 vfs_unmountall(); 339 } 340 tsleep(boot, 0, "shutdn", hz / 10 + 1); 341 } 342 343 print_uptime(); 344 345 /* 346 * Ok, now do things that assume all filesystem activity has 347 * been completed. 348 */ 349 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 350 crit_enter(); 351 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold) 352 dumpsys(); 353 354 /* Now that we're going to really halt the system... */ 355 EVENTHANDLER_INVOKE(shutdown_final, howto); 356 357 for(;;) ; /* safety against shutdown_reset not working */ 358 /* NOTREACHED */ 359 } 360 361 /* 362 * If the shutdown was a clean halt, behave accordingly. 363 */ 364 static void 365 shutdown_halt(void *junk, int howto) 366 { 367 if (howto & RB_HALT) { 368 printf("\n"); 369 printf("The operating system has halted.\n"); 370 printf("Please press any key to reboot.\n\n"); 371 switch (cngetc()) { 372 case -1: /* No console, just die */ 373 cpu_halt(); 374 /* NOTREACHED */ 375 default: 376 howto &= ~RB_HALT; 377 break; 378 } 379 } 380 } 381 382 /* 383 * Check to see if the system paniced, pause and then reboot 384 * according to the specified delay. 385 */ 386 static void 387 shutdown_panic(void *junk, int howto) 388 { 389 int loop; 390 391 if (howto & RB_DUMP) { 392 if (PANIC_REBOOT_WAIT_TIME != 0) { 393 if (PANIC_REBOOT_WAIT_TIME != -1) { 394 printf("Automatic reboot in %d seconds - " 395 "press a key on the console to abort\n", 396 PANIC_REBOOT_WAIT_TIME); 397 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 398 loop > 0; --loop) { 399 DELAY(1000 * 100); /* 1/10th second */ 400 /* Did user type a key? */ 401 if (cncheckc() != -1) 402 break; 403 } 404 if (!loop) 405 return; 406 } 407 } else { /* zero time specified - reboot NOW */ 408 return; 409 } 410 printf("--> Press a key on the console to reboot,\n"); 411 printf("--> or switch off the system now.\n"); 412 cngetc(); 413 } 414 } 415 416 /* 417 * Everything done, now reset 418 */ 419 static void 420 shutdown_reset(void *junk, int howto) 421 { 422 printf("Rebooting...\n"); 423 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */ 424 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 425 cpu_reset(); 426 /* NOTREACHED */ /* assuming reset worked */ 427 } 428 429 /* 430 * Magic number for savecore 431 * 432 * exported (symorder) and used at least by savecore(8) 433 * 434 */ 435 static u_long const dumpmag = 0x8fca0101UL; 436 437 static int dumpsize = 0; /* also for savecore */ 438 439 static int dodump = 1; 440 441 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, 442 "Try to perform coredump on kernel panic"); 443 444 static int 445 setdumpdev(dev) 446 dev_t dev; 447 { 448 int psize; 449 long newdumplo; 450 451 if (dev == NODEV) { 452 dumpdev = dev; 453 return (0); 454 } 455 psize = dev_dpsize(dev); 456 if (psize == -1) 457 return (ENXIO); 458 /* 459 * XXX should clean up checking in dumpsys() to be more like this. 460 */ 461 newdumplo = psize - Maxmem * (PAGE_SIZE / DEV_BSIZE); 462 if (newdumplo <= LABELSECTOR) 463 return (ENOSPC); 464 dumpdev = dev; 465 dumplo = newdumplo; 466 return (0); 467 } 468 469 470 /* ARGSUSED */ 471 static void dump_conf (void *dummy); 472 static void 473 dump_conf(dummy) 474 void *dummy; 475 { 476 char *path; 477 dev_t dev; 478 479 path = malloc(MNAMELEN, M_TEMP, M_WAITOK); 480 if (TUNABLE_STR_FETCH("dumpdev", path, MNAMELEN) != 0) { 481 dev = getdiskbyname(path); 482 if (dev != NODEV) 483 dumpdev = dev; 484 } 485 free(path, M_TEMP); 486 if (setdumpdev(dumpdev) != 0) 487 dumpdev = NODEV; 488 } 489 490 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL) 491 492 static int 493 sysctl_kern_dumpdev(SYSCTL_HANDLER_ARGS) 494 { 495 int error; 496 udev_t ndumpdev; 497 498 ndumpdev = dev2udev(dumpdev); 499 error = sysctl_handle_opaque(oidp, &ndumpdev, sizeof ndumpdev, req); 500 if (error == 0 && req->newptr != NULL) 501 error = setdumpdev(udev2dev(ndumpdev, 0)); 502 return (error); 503 } 504 505 SYSCTL_PROC(_kern, KERN_DUMPDEV, dumpdev, CTLTYPE_OPAQUE|CTLFLAG_RW, 506 0, sizeof dumpdev, sysctl_kern_dumpdev, "T,dev_t", ""); 507 508 /* 509 * Doadump comes here after turning off memory management and 510 * getting on the dump stack, either when called above, or by 511 * the auto-restart code. 512 */ 513 static void 514 dumpsys(void) 515 { 516 int error; 517 518 savectx(&dumppcb); 519 if (dumping++) { 520 printf("Dump already in progress, bailing...\n"); 521 return; 522 } 523 if (!dodump) 524 return; 525 if (dumpdev == NODEV) 526 return; 527 dumpsize = Maxmem; 528 printf("\ndumping to dev %s, offset %ld\n", devtoname(dumpdev), dumplo); 529 printf("dump "); 530 error = dev_ddump(dumpdev); 531 if (error == 0) { 532 printf("succeeded\n"); 533 return; 534 } 535 printf("failed, reason: "); 536 switch (error) { 537 case ENOSYS: 538 case ENODEV: 539 printf("device doesn't support a dump routine\n"); 540 break; 541 542 case ENXIO: 543 printf("device bad\n"); 544 break; 545 546 case EFAULT: 547 printf("device not ready\n"); 548 break; 549 550 case EINVAL: 551 printf("area improper\n"); 552 break; 553 554 case EIO: 555 printf("i/o error\n"); 556 break; 557 558 case EINTR: 559 printf("aborted from console\n"); 560 break; 561 562 default: 563 printf("unknown, error = %d\n", error); 564 break; 565 } 566 } 567 568 int 569 dumpstatus(vm_offset_t addr, off_t count) 570 { 571 int c; 572 573 if (addr % (1024 * 1024) == 0) { 574 #ifdef HW_WDOG 575 if (wdog_tickler) 576 (*wdog_tickler)(); 577 #endif 578 printf("%ld ", (long)(count / (1024 * 1024))); 579 } 580 581 if ((c = cncheckc()) == 0x03) 582 return -1; 583 else if (c != -1) 584 printf("[CTRL-C to abort] "); 585 586 return 0; 587 } 588 589 /* 590 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 591 * and then reboots. If we are called twice, then we avoid trying to sync 592 * the disks as this often leads to recursive panics. 593 */ 594 void 595 panic(const char *fmt, ...) 596 { 597 int bootopt, newpanic; 598 __va_list ap; 599 static char buf[256]; 600 601 #ifdef SMP 602 /* 603 * If a panic occurs on multiple cpus before the first is able to 604 * halt the other cpus, only one cpu is allowed to take the panic. 605 * Attempt to be verbose about this situation but if the printf() 606 * itself panics don't let us overrun the kernel stack. 607 * 608 * Be very nasty about descheduling our thread at the lowest 609 * level possible in an attempt to freeze the thread without 610 * inducing further panics. 611 * 612 * Bumping gd_trap_nesting_level will also bypass assertions in 613 * lwkt_switch() and allow us to switch away even if we are a 614 * FAST interrupt or IPI. 615 */ 616 if (atomic_poll_acquire_int(&panic_cpu_interlock)) { 617 panic_cpu_gd = mycpu; 618 } else if (panic_cpu_gd != mycpu) { 619 crit_enter(); 620 ++mycpu->gd_trap_nesting_level; 621 if (mycpu->gd_trap_nesting_level < 25) { 622 printf("SECONDARY PANIC ON CPU %d THREAD %p\n", 623 mycpu->gd_cpuid, curthread); 624 } 625 curthread->td_release = NULL; /* be a grinch */ 626 for (;;) { 627 lwkt_deschedule_self(curthread); 628 lwkt_switch(); 629 } 630 /* NOT REACHED */ 631 /* --mycpu->gd_trap_nesting_level */ 632 /* crit_exit() */ 633 } 634 #endif 635 bootopt = RB_AUTOBOOT | RB_DUMP; 636 if (sync_on_panic == 0) 637 bootopt |= RB_NOSYNC; 638 newpanic = 0; 639 if (panicstr) 640 bootopt |= RB_NOSYNC; 641 else { 642 panicstr = fmt; 643 newpanic = 1; 644 } 645 646 __va_start(ap, fmt); 647 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 648 if (panicstr == fmt) 649 panicstr = buf; 650 __va_end(ap); 651 printf("panic: %s\n", buf); 652 #ifdef SMP 653 /* three separate prints in case of an unmapped page and trap */ 654 printf("mp_lock = %08x; ", mp_lock); 655 printf("cpuid = %d; ", mycpu->gd_cpuid); 656 printf("lapic.id = %08x\n", lapic.id); 657 #endif 658 659 #if defined(DDB) 660 if (newpanic && trace_on_panic) 661 db_print_backtrace(); 662 if (debugger_on_panic) 663 Debugger ("panic"); 664 #endif 665 boot(bootopt); 666 } 667 668 /* 669 * Support for poweroff delay. 670 */ 671 #ifndef POWEROFF_DELAY 672 # define POWEROFF_DELAY 5000 673 #endif 674 static int poweroff_delay = POWEROFF_DELAY; 675 676 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 677 &poweroff_delay, 0, ""); 678 679 static void 680 poweroff_wait(void *junk, int howto) 681 { 682 if(!(howto & RB_POWEROFF) || poweroff_delay <= 0) 683 return; 684 DELAY(poweroff_delay * 1000); 685 } 686 687 /* 688 * Some system processes (e.g. syncer) need to be stopped at appropriate 689 * points in their main loops prior to a system shutdown, so that they 690 * won't interfere with the shutdown process (e.g. by holding a disk buf 691 * to cause sync to fail). For each of these system processes, register 692 * shutdown_kproc() as a handler for one of shutdown events. 693 */ 694 static int kproc_shutdown_wait = 60; 695 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 696 &kproc_shutdown_wait, 0, ""); 697 698 void 699 shutdown_kproc(void *arg, int howto) 700 { 701 struct thread *td; 702 struct proc *p; 703 int error; 704 705 if (panicstr) 706 return; 707 708 td = (struct thread *)arg; 709 if ((p = td->td_proc) != NULL) { 710 printf("Waiting (max %d seconds) for system process `%s' to stop...", 711 kproc_shutdown_wait, p->p_comm); 712 } else { 713 printf("Waiting (max %d seconds) for system thread %s to stop...", 714 kproc_shutdown_wait, td->td_comm); 715 } 716 error = suspend_kproc(td, kproc_shutdown_wait * hz); 717 718 if (error == EWOULDBLOCK) 719 printf("timed out\n"); 720 else 721 printf("stopped\n"); 722 } 723