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38 * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94
39 * $FreeBSD: src/sys/kern/kern_exit.c,v 1.92.2.11 2003/01/13 22:51:16 dillon Exp $
40 * $DragonFly: src/sys/kern/kern_exit.c,v 1.91 2008/05/18 20:02:02 nth Exp $
43 #include "opt_compat.h"
44 #include "opt_ktrace.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/sysproto.h>
49 #include <sys/kernel.h>
50 #include <sys/malloc.h>
52 #include <sys/ktrace.h>
53 #include <sys/pioctl.h>
56 #include <sys/vnode.h>
57 #include <sys/resourcevar.h>
58 #include <sys/signalvar.h>
59 #include <sys/taskqueue.h>
60 #include <sys/ptrace.h>
61 #include <sys/acct.h> /* for acct_process() function prototype */
62 #include <sys/filedesc.h>
66 #include <sys/kern_syscall.h>
67 #include <sys/upcall.h>
69 #include <sys/unistd.h>
70 #include <sys/eventhandler.h>
71 #include <sys/dsched.h>
74 #include <vm/vm_param.h>
77 #include <vm/vm_map.h>
78 #include <vm/vm_extern.h>
81 #include <sys/refcount.h>
82 #include <sys/thread2.h>
83 #include <sys/sysref2.h>
84 #include <sys/mplock2.h>
86 static void reaplwps(void *context, int dummy);
87 static void reaplwp(struct lwp *lp);
88 static void killlwps(struct lwp *lp);
90 static MALLOC_DEFINE(M_ATEXIT, "atexit", "atexit callback");
91 static MALLOC_DEFINE(M_ZOMBIE, "zombie", "zombie proc status");
93 static struct lwkt_token deadlwp_token = LWKT_TOKEN_INITIALIZER(deadlwp_token);
96 * callout list for things to do at exit time
100 TAILQ_ENTRY(exitlist) next;
103 TAILQ_HEAD(exit_list_head, exitlist);
104 static struct exit_list_head exit_list = TAILQ_HEAD_INITIALIZER(exit_list);
109 struct task *deadlwp_task[MAXCPU];
110 struct lwplist deadlwp_list[MAXCPU];
116 * SYS_EXIT_ARGS(int rval)
119 sys_exit(struct exit_args *uap)
121 exit1(W_EXITCODE(uap->rval, 0));
127 * Death of a lwp or process with optional bells and whistles.
132 sys_extexit(struct extexit_args *uap)
134 struct proc *p = curproc;
138 action = EXTEXIT_ACTION(uap->how);
139 who = EXTEXIT_WHO(uap->how);
141 /* Check parameters before we might perform some action */
154 error = copyout(&uap->status, uap->addr, sizeof(uap->status));
162 lwkt_gettoken(&p->p_token);
167 * Be sure only to perform a simple lwp exit if there is at
168 * least one more lwp in the proc, which will call exit1()
169 * later, otherwise the proc will be an UNDEAD and not even a
172 if (p->p_nthreads > 1) {
173 lwp_exit(0); /* called w/ p_token held */
176 /* else last lwp in proc: do the real thing */
178 default: /* to help gcc */
180 lwkt_reltoken(&p->p_token);
181 exit1(W_EXITCODE(uap->status, 0));
186 lwkt_reltoken(&p->p_token); /* safety */
190 * Kill all lwps associated with the current process except the
191 * current lwp. Return an error if we race another thread trying to
192 * do the same thing and lose the race.
194 * If forexec is non-zero the current thread and process flags are
195 * cleaned up so they can be reused.
198 killalllwps(int forexec)
200 struct lwp *lp = curthread->td_lwp;
201 struct proc *p = lp->lwp_proc;
204 * Interlock against P_WEXIT. Only one of the process's thread
205 * is allowed to do the master exit.
207 if (p->p_flag & P_WEXIT)
209 p->p_flag |= P_WEXIT;
212 * Interlock with LWP_WEXIT and kill any remaining LWPs
214 lp->lwp_flag |= LWP_WEXIT;
215 if (p->p_nthreads > 1)
219 * If doing this for an exec, clean up the remaining thread
220 * (us) for continuing operation after all the other threads
224 lp->lwp_flag &= ~LWP_WEXIT;
225 p->p_flag &= ~P_WEXIT;
231 * Kill all LWPs except the current one. Do not try to signal
232 * LWPs which have exited on their own or have already been
236 killlwps(struct lwp *lp)
238 struct proc *p = lp->lwp_proc;
242 * Kill the remaining LWPs. We must send the signal before setting
243 * LWP_WEXIT. The setting of WEXIT is optional but helps reduce
244 * races. tlp must be held across the call as it might block and
245 * allow the target lwp to rip itself out from under our loop.
247 FOREACH_LWP_IN_PROC(tlp, p) {
249 if ((tlp->lwp_flag & LWP_WEXIT) == 0) {
250 lwpsignal(p, tlp, SIGKILL);
251 tlp->lwp_flag |= LWP_WEXIT;
257 * Wait for everything to clear out.
259 while (p->p_nthreads > 1) {
260 tsleep(&p->p_nthreads, 0, "killlwps", 0);
265 * Exit: deallocate address space and other resources, change proc state
266 * to zombie, and unlink proc from allproc and parent's lists. Save exit
267 * status and rusage for wait(). Check for child processes and orphan them.
272 struct thread *td = curthread;
273 struct proc *p = td->td_proc;
274 struct lwp *lp = td->td_lwp;
281 lwkt_gettoken(&p->p_token);
284 kprintf("init died (signal %d, exit %d)\n",
285 WTERMSIG(rv), WEXITSTATUS(rv));
286 panic("Going nowhere without my init!");
288 varsymset_clean(&p->p_varsymset);
289 lockuninit(&p->p_varsymset.vx_lock);
291 * Kill all lwps associated with the current process, return an
292 * error if we race another thread trying to do the same thing
295 error = killalllwps(0);
301 caps_exit(lp->lwp_thread);
303 /* are we a task leader? */
304 if (p == p->p_leader) {
305 struct kill_args killArgs;
306 killArgs.signum = SIGKILL;
309 killArgs.pid = q->p_pid;
311 * The interface for kill is better
312 * than the internal signal
319 tsleep((caddr_t)p, 0, "exit1", 0);
325 STOPEVENT(p, S_EXIT, rv);
326 wakeup(&p->p_stype); /* Wakeup anyone in procfs' PIOCWAIT */
329 * Check if any loadable modules need anything done at process exit.
330 * e.g. SYSV IPC stuff
331 * XXX what if one of these generates an error?
334 EVENTHANDLER_INVOKE(process_exit, p);
337 * XXX: imho, the eventhandler stuff is much cleaner than this.
338 * Maybe we should move everything to use eventhandler.
340 TAILQ_FOREACH(ep, &exit_list, next)
343 if (p->p_flag & P_PROFIL)
346 * If parent is waiting for us to exit or exec,
347 * P_PPWAIT is set; we will wakeup the parent below.
349 p->p_flag &= ~(P_TRACED | P_PPWAIT);
350 SIGEMPTYSET(p->p_siglist);
351 SIGEMPTYSET(lp->lwp_siglist);
352 if (timevalisset(&p->p_realtimer.it_value))
353 callout_stop(&p->p_ithandle);
356 * Reset any sigio structures pointing to us as a result of
357 * F_SETOWN with our pid.
359 funsetownlst(&p->p_sigiolst);
362 * Close open files and release open-file table.
367 if(p->p_leader->p_peers) {
369 while(q->p_peers != p)
371 q->p_peers = p->p_peers;
372 wakeup((caddr_t)p->p_leader);
376 * XXX Shutdown SYSV semaphores
380 KKASSERT(p->p_numposixlocks == 0);
382 /* The next two chunks should probably be moved to vmspace_exit. */
386 * Release upcalls associated with this process
392 * Clean up data related to virtual kernel operation. Clean up
393 * any vkernel context related to the current lwp now so we can
397 vkernel_lwp_exit(lp);
402 * Release user portion of address space.
403 * This releases references to vnodes,
404 * which could cause I/O if the file has been unlinked.
405 * Need to do this early enough that we can still sleep.
406 * Can't free the entire vmspace as the kernel stack
407 * may be mapped within that space also.
409 * Processes sharing the same vmspace may exit in one order, and
410 * get cleaned up by vmspace_exit() in a different order. The
411 * last exiting process to reach this point releases as much of
412 * the environment as it can, and the last process cleaned up
413 * by vmspace_exit() (which decrements exitingcnt) cleans up the
416 vmspace_exitbump(vm);
417 sysref_put(&vm->vm_sysref);
419 if (SESS_LEADER(p)) {
420 struct session *sp = p->p_session;
424 * We are the controlling process. Signal the
425 * foreground process group, drain the controlling
426 * terminal, and revoke access to the controlling
429 * NOTE: while waiting for the process group to exit
430 * it is possible that one of the processes in the
431 * group will revoke the tty, so the ttyclosesession()
432 * function will re-check sp->s_ttyvp.
434 if (sp->s_ttyp && (sp->s_ttyp->t_session == sp)) {
435 if (sp->s_ttyp->t_pgrp)
436 pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1);
438 ttyclosesession(sp, 1); /* also revoke */
441 * Release the tty. If someone has it open via
442 * /dev/tty then close it (since they no longer can
443 * once we've NULL'd it out).
445 ttyclosesession(sp, 0);
448 * s_ttyp is not zero'd; we use this to indicate
449 * that the session once had a controlling terminal.
450 * (for logging and informational purposes)
455 fixjobc(p, p->p_pgrp, 0);
456 (void)acct_process(p);
462 ktrdestroy(&p->p_tracenode);
466 * Release reference to text vnode
468 if ((vtmp = p->p_textvp) != NULL) {
473 /* Release namecache handle to text file */
474 if (p->p_textnch.ncp)
475 cache_drop(&p->p_textnch);
478 * Move the process to the zombie list. This will block
479 * until the process p_lock count reaches 0. The process will
480 * not be reaped until TDF_EXITING is set by cpu_thread_exit(),
481 * which is called from cpu_proc_exit().
483 proc_move_allproc_zombie(p);
486 * Reparent all of this process's children to the init process.
487 * We must hold initproc->p_token in order to mess with
488 * initproc->p_children. We already hold p->p_token (to remove
489 * the children from our list).
491 q = LIST_FIRST(&p->p_children);
493 lwkt_gettoken(&initproc->p_token);
495 nq = LIST_NEXT(q, p_sibling);
496 LIST_REMOVE(q, p_sibling);
497 LIST_INSERT_HEAD(&initproc->p_children, q, p_sibling);
498 q->p_pptr = initproc;
499 q->p_sigparent = SIGCHLD;
501 * Traced processes are killed
502 * since their existence means someone is screwing up.
504 if (q->p_flag & P_TRACED) {
505 q->p_flag &= ~P_TRACED;
510 lwkt_reltoken(&initproc->p_token);
515 * Save exit status and final rusage info, adding in child rusage
516 * info and self times.
518 calcru_proc(p, &p->p_ru);
519 ruadd(&p->p_ru, &p->p_cru);
522 * notify interested parties of our demise.
524 KNOTE(&p->p_klist, NOTE_EXIT);
527 * Notify parent that we're gone. If parent has the PS_NOCLDWAIT
528 * flag set, notify process 1 instead (and hope it will handle
531 if (p->p_pptr->p_sigacts->ps_flag & PS_NOCLDWAIT) {
532 struct proc *pp = p->p_pptr;
535 proc_reparent(p, initproc);
538 * If this was the last child of our parent, notify
539 * parent, so in case he was wait(2)ing, he will
540 * continue. This function interlocks with pptr->p_token.
542 if (LIST_EMPTY(&pp->p_children))
547 /* lwkt_gettoken(&proc_token); */
550 if (p->p_sigparent && q != initproc) {
551 ksignal(q, p->p_sigparent);
557 /* lwkt_reltoken(&proc_token); */
558 /* NOTE: p->p_pptr can get ripped out */
560 * cpu_exit is responsible for clearing curproc, since
561 * it is heavily integrated with the thread/switching sequence.
563 * Other substructures are freed from wait().
568 * Release the current user process designation on the process so
569 * the userland scheduler can work in someone else.
571 p->p_usched->release_curproc(lp);
574 * Finally, call machine-dependent code to release as many of the
575 * lwp's resources as we can and halt execution of this thread.
581 * Eventually called by every exiting LWP
583 * p->p_token must be held. mplock may be held and will be released.
586 lwp_exit(int masterexit)
588 struct thread *td = curthread;
589 struct lwp *lp = td->td_lwp;
590 struct proc *p = lp->lwp_proc;
593 * lwp_exit() may be called without setting LWP_WEXIT, so
594 * make sure it is set here.
596 ASSERT_LWKT_TOKEN_HELD(&p->p_token);
597 lp->lwp_flag |= LWP_WEXIT;
600 * Clean up any virtualization
603 vkernel_lwp_exit(lp);
606 * Clean up select/poll support
608 kqueue_terminate(&lp->lwp_kqueue);
611 * Clean up any syscall-cached ucred
614 crfree(td->td_ucred);
619 * Nobody actually wakes us when the lock
620 * count reaches zero, so just wait one tick.
622 while (lp->lwp_lock > 0)
623 tsleep(lp, 0, "lwpexit", 1);
625 /* Hand down resource usage to our proc */
626 ruadd(&p->p_ru, &lp->lwp_ru);
629 * If we don't hold the process until the LWP is reaped wait*()
630 * may try to dispose of its vmspace before all the LWPs have
631 * actually terminated.
636 * Do any remaining work that might block on us. We should be
637 * coded such that further blocking is ok after decrementing
638 * p_nthreads but don't take the chance.
640 dsched_exit_thread(td);
641 biosched_done(curthread);
644 * We have to use the reaper for all the LWPs except the one doing
645 * the master exit. The LWP doing the master exit can just be
646 * left on p_lwps and the process reaper will deal with it
647 * synchronously, which is much faster.
649 * Wakeup anyone waiting on p_nthreads to drop to 1 or 0.
651 if (masterexit == 0) {
652 lwp_rb_tree_RB_REMOVE(&p->p_lwp_tree, lp);
654 if (p->p_nthreads <= 1)
655 wakeup(&p->p_nthreads);
656 lwkt_gettoken(&deadlwp_token);
657 LIST_INSERT_HEAD(&deadlwp_list[mycpuid], lp, u.lwp_reap_entry);
658 taskqueue_enqueue(taskqueue_thread[mycpuid],
659 deadlwp_task[mycpuid]);
660 lwkt_reltoken(&deadlwp_token);
663 if (p->p_nthreads <= 1)
664 wakeup(&p->p_nthreads);
668 * Release p_token. The mp_token may also be held and we depend on
669 * the lwkt_switch() code to clean it up.
671 lwkt_reltoken(&p->p_token);
676 * Wait until a lwp is completely dead.
678 * If the thread is still executing, which can't be waited upon,
679 * return failure. The caller is responsible of waiting a little
680 * bit and checking again.
683 * while (!lwp_wait(lp))
684 * tsleep(lp, 0, "lwpwait", 1);
687 lwp_wait(struct lwp *lp)
689 struct thread *td = lp->lwp_thread;;
691 KKASSERT(lwkt_preempted_proc() != lp);
693 while (lp->lwp_lock > 0)
694 tsleep(lp, 0, "lwpwait1", 1);
699 * The lwp's thread may still be in the middle
700 * of switching away, we can't rip its stack out from
701 * under it until TDF_EXITING is set and both
702 * TDF_RUNNING and TDF_PREEMPT_LOCK are clear.
703 * TDF_PREEMPT_LOCK must be checked because TDF_RUNNING
704 * will be cleared temporarily if a thread gets
707 * YYY no wakeup occurs, so we simply return failure
708 * and let the caller deal with sleeping and calling
711 if ((td->td_flags & (TDF_RUNNING|TDF_PREEMPT_LOCK|
712 TDF_EXITING|TDF_RUNQ)) != TDF_EXITING) {
715 KASSERT((td->td_flags & TDF_TSLEEPQ) == 0,
716 ("lwp_wait: td %p (%s) still on sleep queue", td, td->td_comm));
721 * Release the resources associated with a lwp.
722 * The lwp must be completely dead.
725 lwp_dispose(struct lwp *lp)
727 struct thread *td = lp->lwp_thread;;
729 KKASSERT(lwkt_preempted_proc() != lp);
730 KKASSERT(td->td_refs == 0);
731 KKASSERT((td->td_flags & (TDF_RUNNING|TDF_PREEMPT_LOCK|TDF_EXITING)) ==
739 lp->lwp_thread = NULL;
740 lwkt_free_thread(td);
749 sys_wait4(struct wait_args *uap)
751 struct rusage rusage;
754 error = kern_wait(uap->pid, (uap->status ? &status : NULL),
755 uap->options, (uap->rusage ? &rusage : NULL),
756 &uap->sysmsg_result);
758 if (error == 0 && uap->status)
759 error = copyout(&status, uap->status, sizeof(*uap->status));
760 if (error == 0 && uap->rusage)
761 error = copyout(&rusage, uap->rusage, sizeof(*uap->rusage));
768 * wait_args(int pid, int *status, int options, struct rusage *rusage)
773 kern_wait(pid_t pid, int *status, int options, struct rusage *rusage, int *res)
775 struct thread *td = curthread;
777 struct proc *q = td->td_proc;
785 if (options &~ (WUNTRACED|WNOHANG|WCONTINUED|WLINUXCLONE))
788 lwkt_gettoken(&q->p_token);
791 * All sorts of things can change due to blocking so we have to loop
792 * all the way back up here.
794 * The problem is that if a process group is stopped and the parent
795 * is doing a wait*(..., WUNTRACED, ...), it will see the STOP
796 * of the child and then stop itself when it tries to return from the
797 * system call. When the process group is resumed the parent will
798 * then get the STOP status even though the child has now resumed
799 * (a followup wait*() will get the CONT status).
801 * Previously the CONT would overwrite the STOP because the tstop
802 * was handled within tsleep(), and the parent would only see
803 * the CONT when both are stopped and continued together. This little
804 * two-line hack restores this effect.
806 while (q->p_stat == SSTOP)
814 * NOTE: We don't want to break q's p_token in the loop for the
815 * case where no children are found or we risk breaking the
816 * interlock between child and parent.
818 LIST_FOREACH(p, &q->p_children, p_sibling) {
819 if (pid != WAIT_ANY &&
820 p->p_pid != pid && p->p_pgid != -pid) {
825 * This special case handles a kthread spawned by linux_clone
826 * (see linux_misc.c). The linux_wait4 and linux_waitpid
827 * functions need to be able to distinguish between waiting
828 * on a process and waiting on a thread. It is a thread if
829 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option
830 * signifies we want to wait for threads and not processes.
832 if ((p->p_sigparent != SIGCHLD) ^
833 ((options & WLINUXCLONE) != 0)) {
838 if (p->p_stat == SZOMB) {
840 * We may go into SZOMB with threads still present.
841 * We must wait for them to exit before we can reap
842 * the master thread, otherwise we may race reaping
843 * non-master threads.
845 lwkt_gettoken(&p->p_token);
846 while (p->p_nthreads > 0) {
847 tsleep(&p->p_nthreads, 0, "lwpzomb", hz);
851 * Reap any LWPs left in p->p_lwps. This is usually
852 * just the last LWP. This must be done before
853 * we loop on p_lock since the lwps hold a ref on
854 * it as a vmspace interlock.
856 * Once that is accomplished p_nthreads had better
859 while ((lp = RB_ROOT(&p->p_lwp_tree)) != NULL) {
860 lwp_rb_tree_RB_REMOVE(&p->p_lwp_tree, lp);
863 KKASSERT(p->p_nthreads == 0);
864 lwkt_reltoken(&p->p_token);
867 * Don't do anything really bad until all references
868 * to the process go away. This may include other
869 * LWPs which are still in the process of being
870 * reaped. We can't just pull the rug out from under
871 * them because they may still be using the VM space.
873 * Certain kernel facilities such as /proc will also
874 * put a hold on the process for short periods of
878 tsleep(p, 0, "reap3", hz);
880 /* Take care of our return values. */
882 p->p_usched->heuristic_exiting(td->td_lwp, p);
885 *status = p->p_xstat;
889 * If we got the child via a ptrace 'attach',
890 * we need to give it back to the old parent.
892 if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) {
903 * Unlink the proc from its process group so that
904 * the following operations won't lead to an
905 * inconsistent state for processes running down
908 proc_remove_zombie(p);
912 ruadd(&q->p_cru, &p->p_ru);
915 * Decrement the count of procs running with this uid.
917 chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0);
920 * Free up credentials.
926 * Remove unused arguments
930 if (pa && refcount_release(&pa->ar_ref)) {
937 if (ps && refcount_release(&ps->ps_refcnt)) {
938 kfree(ps, M_SUBPROC);
945 * Temporary refs may still have been acquired while
946 * we removed the process, make sure they are all
947 * gone before kfree()ing. Now that the process has
948 * been removed from all lists and all references to
949 * it have gone away, no new refs can occur.
952 tsleep(p, 0, "reap4", hz);
958 if (p->p_stat == SSTOP && (p->p_flag & P_WAITED) == 0 &&
959 ((p->p_flag & P_TRACED) || (options & WUNTRACED))) {
960 lwkt_gettoken(&p->p_token);
961 p->p_flag |= P_WAITED;
964 p->p_usched->heuristic_exiting(td->td_lwp, p);
966 *status = W_STOPCODE(p->p_xstat);
967 /* Zero rusage so we get something consistent. */
969 bzero(rusage, sizeof(rusage));
971 lwkt_reltoken(&p->p_token);
974 if ((options & WCONTINUED) && (p->p_flag & P_CONTINUED)) {
975 lwkt_gettoken(&p->p_token);
977 p->p_usched->heuristic_exiting(td->td_lwp, p);
978 p->p_flag &= ~P_CONTINUED;
983 lwkt_reltoken(&p->p_token);
991 if (options & WNOHANG) {
998 * Wait for signal - interlocked using q->p_token.
1000 error = tsleep(q, PCATCH, "wait", 0);
1003 lwkt_reltoken(&q->p_token);
1010 * Make process 'parent' the new parent of process 'child'.
1012 * p_children/p_sibling requires the parent's token, and
1013 * changing pptr requires the child's token, so we have to
1014 * get three tokens to do this operation.
1017 proc_reparent(struct proc *child, struct proc *parent)
1019 struct proc *opp = child->p_pptr;
1025 lwkt_gettoken(&opp->p_token);
1026 lwkt_gettoken(&child->p_token);
1027 lwkt_gettoken(&parent->p_token);
1028 KKASSERT(child->p_pptr == opp);
1029 LIST_REMOVE(child, p_sibling);
1030 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
1031 child->p_pptr = parent;
1032 lwkt_reltoken(&parent->p_token);
1033 lwkt_reltoken(&child->p_token);
1034 lwkt_reltoken(&opp->p_token);
1040 * The next two functions are to handle adding/deleting items on the
1044 * Take the arguments given and put them onto the exit callout list,
1045 * However first make sure that it's not already there.
1046 * returns 0 on success.
1050 at_exit(exitlist_fn function)
1052 struct exitlist *ep;
1055 /* Be noisy if the programmer has lost track of things */
1056 if (rm_at_exit(function))
1057 kprintf("WARNING: exit callout entry (%p) already present\n",
1060 ep = kmalloc(sizeof(*ep), M_ATEXIT, M_NOWAIT);
1063 ep->function = function;
1064 TAILQ_INSERT_TAIL(&exit_list, ep, next);
1069 * Scan the exit callout list for the given item and remove it.
1070 * Returns the number of items removed (0 or 1)
1073 rm_at_exit(exitlist_fn function)
1075 struct exitlist *ep;
1077 TAILQ_FOREACH(ep, &exit_list, next) {
1078 if (ep->function == function) {
1079 TAILQ_REMOVE(&exit_list, ep, next);
1080 kfree(ep, M_ATEXIT);
1088 * LWP reaper related code.
1091 reaplwps(void *context, int dummy)
1093 struct lwplist *lwplist = context;
1096 lwkt_gettoken(&deadlwp_token);
1097 while ((lp = LIST_FIRST(lwplist))) {
1098 LIST_REMOVE(lp, u.lwp_reap_entry);
1101 lwkt_reltoken(&deadlwp_token);
1105 reaplwp(struct lwp *lp)
1107 while (lwp_wait(lp) == 0)
1108 tsleep(lp, 0, "lwpreap", 1);
1117 for (cpu = 0; cpu < ncpus; cpu++) {
1118 LIST_INIT(&deadlwp_list[cpu]);
1119 deadlwp_task[cpu] = kmalloc(sizeof(*deadlwp_task[cpu]), M_DEVBUF, M_WAITOK);
1120 TASK_INIT(deadlwp_task[cpu], 0, reaplwps, &deadlwp_list[cpu]);
1124 SYSINIT(deadlwpinit, SI_SUB_CONFIGURE, SI_ORDER_ANY, deadlwp_init, NULL);