2 * Copyright (c) 1982, 1986, 1989, 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
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7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
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11 * modification, are permitted provided that the following conditions
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
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34 * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
41 #include "opt_kdtrace.h"
42 #include "opt_ktrace.h"
43 #include "opt_procdesc.h"
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/sysproto.h>
48 #include <sys/capability.h>
49 #include <sys/eventhandler.h>
50 #include <sys/kernel.h>
51 #include <sys/malloc.h>
53 #include <sys/mutex.h>
55 #include <sys/procdesc.h>
56 #include <sys/pioctl.h>
60 #include <sys/vmmeter.h>
61 #include <sys/vnode.h>
62 #include <sys/racct.h>
63 #include <sys/resourcevar.h>
65 #include <sys/signalvar.h>
66 #include <sys/sched.h>
68 #include <sys/syscallsubr.h>
69 #include <sys/syslog.h>
70 #include <sys/ptrace.h>
71 #include <sys/acct.h> /* for acct_process() function prototype */
72 #include <sys/filedesc.h>
77 #include <sys/ktrace.h>
80 #include <security/audit/audit.h>
81 #include <security/mac/mac_framework.h>
84 #include <vm/vm_extern.h>
85 #include <vm/vm_param.h>
87 #include <vm/vm_map.h>
88 #include <vm/vm_page.h>
92 #include <sys/dtrace_bsd.h>
93 dtrace_execexit_func_t dtrace_fasttrap_exit;
96 SDT_PROVIDER_DECLARE(proc);
97 SDT_PROBE_DEFINE(proc, kernel, , exit, exit);
98 SDT_PROBE_ARGTYPE(proc, kernel, , exit, 0, "int");
100 /* Hook for NFS teardown procedure. */
101 void (*nlminfo_release_p)(struct proc *p);
104 clear_orphan(struct proc *p)
107 PROC_LOCK_ASSERT(p, MA_OWNED);
109 if (p->p_flag & P_ORPHAN) {
110 LIST_REMOVE(p, p_orphan);
111 p->p_flag &= ~P_ORPHAN;
116 * exit -- death of process.
119 sys_sys_exit(struct thread *td, struct sys_exit_args *uap)
122 exit1(td, W_EXITCODE(uap->rval, 0));
127 * Exit: deallocate address space and other resources, change proc state to
128 * zombie, and unlink proc from allproc and parent's lists. Save exit status
129 * and rusage for wait(). Check for child processes and orphan them.
132 exit1(struct thread *td, int rv)
134 struct proc *p, *nq, *q;
136 struct vnode *ttyvp = NULL;
139 mtx_assert(&Giant, MA_NOTOWNED);
143 * XXX in case we're rebooting we just let init die in order to
144 * work around an unsolved stack overflow seen very late during
145 * shutdown on sparc64 when the gmirror worker process exists.
147 if (p == initproc && rebooting == 0) {
148 printf("init died (signal %d, exit %d)\n",
149 WTERMSIG(rv), WEXITSTATUS(rv));
150 panic("Going nowhere without my init!");
154 * MUST abort all other threads before proceeding past here.
157 while (p->p_flag & P_HADTHREADS) {
159 * First check if some other thread got here before us.
160 * If so, act appropriately: exit or suspend.
162 thread_suspend_check(0);
165 * Kill off the other threads. This requires
166 * some co-operation from other parts of the kernel
167 * so it may not be instantaneous. With this state set
168 * any thread entering the kernel from userspace will
169 * thread_exit() in trap(). Any thread attempting to
170 * sleep will return immediately with EINTR or EWOULDBLOCK
171 * which will hopefully force them to back out to userland
172 * freeing resources as they go. Any thread attempting
173 * to return to userland will thread_exit() from userret().
174 * thread_exit() will unsuspend us when the last of the
175 * other threads exits.
176 * If there is already a thread singler after resumption,
177 * calling thread_single will fail; in that case, we just
178 * re-check all suspension request, the thread should
179 * either be suspended there or exit.
181 if (!thread_single(SINGLE_EXIT))
185 * All other activity in this process is now stopped.
186 * Threading support has been turned off.
189 KASSERT(p->p_numthreads == 1,
190 ("exit1: proc %p exiting with %d threads", p, p->p_numthreads));
191 racct_sub(p, RACCT_NTHR, 1);
193 * Wakeup anyone in procfs' PIOCWAIT. They should have a hold
194 * on our vmspace, so we should block below until they have
195 * released their reference to us. Note that if they have
196 * requested S_EXIT stops we will block here until they ack
199 _STOPEVENT(p, S_EXIT, rv);
202 * Ignore any pending request to stop due to a stop signal.
203 * Once P_WEXIT is set, future requests will be ignored as
206 p->p_flag &= ~P_STOPPED_SIG;
207 KASSERT(!P_SHOULDSTOP(p), ("exiting process is stopped"));
210 * Note that we are exiting and do another wakeup of anyone in
211 * PIOCWAIT in case they aren't listening for S_EXIT stops or
212 * decided to wait again after we told them we are exiting.
214 p->p_flag |= P_WEXIT;
218 * Wait for any processes that have a hold on our vmspace to
219 * release their reference.
221 while (p->p_lock > 0)
222 msleep(&p->p_lock, &p->p_mtx, PWAIT, "exithold", 0);
224 p->p_xstat = rv; /* Let event handler change exit status */
226 /* Drain the limit callout while we don't have the proc locked */
227 callout_drain(&p->p_limco);
231 * The Sun BSM exit token contains two components: an exit status as
232 * passed to exit(), and a return value to indicate what sort of exit
233 * it was. The exit status is WEXITSTATUS(rv), but it's not clear
234 * what the return value is.
236 AUDIT_ARG_EXIT(WEXITSTATUS(rv), 0);
237 AUDIT_SYSCALL_EXIT(0, td);
240 /* Are we a task leader? */
241 if (p == p->p_leader) {
242 mtx_lock(&ppeers_lock);
246 kern_psignal(q, SIGKILL);
250 while (p->p_peers != NULL)
251 msleep(p, &ppeers_lock, PWAIT, "exit1", 0);
252 mtx_unlock(&ppeers_lock);
256 * Check if any loadable modules need anything done at process exit.
257 * E.g. SYSV IPC stuff
258 * XXX what if one of these generates an error?
260 EVENTHANDLER_INVOKE(process_exit, p);
263 * If parent is waiting for us to exit or exec,
264 * P_PPWAIT is set; we will wakeup the parent below.
267 rv = p->p_xstat; /* Event handler could change exit status */
269 p->p_flag &= ~(P_TRACED | P_PPWAIT);
272 * Stop the real interval timer. If the handler is currently
273 * executing, prevent it from rearming itself and let it finish.
275 if (timevalisset(&p->p_realtimer.it_value) &&
276 callout_stop(&p->p_itcallout) == 0) {
277 timevalclear(&p->p_realtimer.it_interval);
278 msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0);
279 KASSERT(!timevalisset(&p->p_realtimer.it_value),
280 ("realtime timer is still armed"));
285 * Reset any sigio structures pointing to us as a result of
286 * F_SETOWN with our pid.
288 funsetownlst(&p->p_sigiolst);
291 * If this process has an nlminfo data area (for lockd), release it
293 if (nlminfo_release_p != NULL && p->p_nlminfo != NULL)
294 (*nlminfo_release_p)(p);
297 * Close open files and release open-file table.
303 * If this thread tickled GEOM, we need to wait for the giggling to
304 * stop before we return to userland
306 if (td->td_pflags & TDP_GEOM)
310 * Remove ourself from our leader's peer list and wake our leader.
312 mtx_lock(&ppeers_lock);
313 if (p->p_leader->p_peers) {
315 while (q->p_peers != p)
317 q->p_peers = p->p_peers;
320 mtx_unlock(&ppeers_lock);
324 sx_xlock(&proctree_lock);
325 if (SESS_LEADER(p)) {
326 struct session *sp = p->p_session;
330 * s_ttyp is not zero'd; we use this to indicate that
331 * the session once had a controlling terminal. (for
332 * logging and informational purposes)
343 * Signal foreground pgrp and revoke access to
344 * controlling terminal if it has not been revoked
347 * Because the TTY may have been revoked in the mean
348 * time and could already have a new session associated
349 * with it, make sure we don't send a SIGHUP to a
350 * foreground process group that does not belong to this
356 if (tp->t_session == sp)
357 tty_signal_pgrp(tp, SIGHUP);
362 sx_xunlock(&proctree_lock);
363 if (vn_lock(ttyvp, LK_EXCLUSIVE) == 0) {
364 VOP_REVOKE(ttyvp, REVOKEALL);
365 VOP_UNLOCK(ttyvp, 0);
367 sx_xlock(&proctree_lock);
370 fixjobc(p, p->p_pgrp, 0);
371 sx_xunlock(&proctree_lock);
372 (void)acct_process(td);
374 /* Release the TTY now we've unlocked everything. */
381 * Release reference to text vnode
383 if ((vtmp = p->p_textvp) != NULL) {
389 * Release our limits structure.
400 * Remove proc from allproc queue and pidhash chain.
401 * Place onto zombproc. Unlink from parent's child list.
403 sx_xlock(&allproc_lock);
404 LIST_REMOVE(p, p_list);
405 LIST_INSERT_HEAD(&zombproc, p, p_list);
406 LIST_REMOVE(p, p_hash);
407 sx_xunlock(&allproc_lock);
410 * Call machine-dependent code to release any
411 * machine-dependent resources other than the address space.
412 * The address space is released by "vmspace_exitfree(p)" in
417 WITNESS_WARN(WARN_PANIC, NULL, "process (pid %d) exiting", p->p_pid);
420 * Reparent all of our children to init.
422 sx_xlock(&proctree_lock);
423 q = LIST_FIRST(&p->p_children);
424 if (q != NULL) /* only need this if any child is S_ZOMB */
426 for (; q != NULL; q = nq) {
427 nq = LIST_NEXT(q, p_sibling);
429 proc_reparent(q, initproc);
430 q->p_sigparent = SIGCHLD;
432 * Traced processes are killed
433 * since their existence means someone is screwing up.
435 if (q->p_flag & P_TRACED) {
439 * Since q was found on our children list, the
440 * proc_reparent() call moved q to the orphan
441 * list due to present P_TRACED flag. Clear
442 * orphan link for q now while q is locked.
445 q->p_flag &= ~(P_TRACED | P_STOPPED_TRACE);
446 FOREACH_THREAD_IN_PROC(q, temp)
447 temp->td_dbgflags &= ~TDB_SUSPEND;
448 kern_psignal(q, SIGKILL);
454 * Also get rid of our orphans.
456 while ((q = LIST_FIRST(&p->p_orphans)) != NULL) {
462 /* Save exit status. */
466 /* Tell the prison that we are gone. */
467 prison_proc_free(p->p_ucred->cr_prison);
471 * Tell the DTrace fasttrap provider about the exit if it
472 * has declared an interest.
474 if (dtrace_fasttrap_exit)
475 dtrace_fasttrap_exit(p);
479 * Notify interested parties of our demise.
481 KNOTE_LOCKED(&p->p_klist, NOTE_EXIT);
484 int reason = CLD_EXITED;
487 else if (WIFSIGNALED(rv))
489 SDT_PROBE(proc, kernel, , exit, reason, 0, 0, 0, 0);
493 * Just delete all entries in the p_klist. At this point we won't
494 * report any more events, and there are nasty race conditions that
495 * can beat us if we don't.
497 knlist_clear(&p->p_klist, 1);
500 * If this is a process with a descriptor, we may not need to deliver
501 * a signal to the parent. proctree_lock is held over
502 * procdesc_exit() to serialize concurrent calls to close() and
506 if (p->p_procdesc == NULL || procdesc_exit(p)) {
509 * Notify parent that we're gone. If parent has the
510 * PS_NOCLDWAIT flag set, or if the handler is set to SIG_IGN,
511 * notify process 1 instead (and hope it will handle this
514 PROC_LOCK(p->p_pptr);
515 mtx_lock(&p->p_pptr->p_sigacts->ps_mtx);
516 if (p->p_pptr->p_sigacts->ps_flag &
517 (PS_NOCLDWAIT | PS_CLDSIGIGN)) {
520 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
523 proc_reparent(p, initproc);
524 p->p_sigparent = SIGCHLD;
525 PROC_LOCK(p->p_pptr);
528 * Notify parent, so in case he was wait(2)ing or
529 * executing waitpid(2) with our pid, he will
534 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
536 if (p->p_pptr == initproc)
537 kern_psignal(p->p_pptr, SIGCHLD);
538 else if (p->p_sigparent != 0) {
539 if (p->p_sigparent == SIGCHLD)
541 else /* LINUX thread */
542 kern_psignal(p->p_pptr, p->p_sigparent);
546 PROC_LOCK(p->p_pptr);
548 sx_xunlock(&proctree_lock);
551 * The state PRS_ZOMBIE prevents other proesses from sending
552 * signal to the process, to avoid memory leak, we free memory
553 * for signal queue at the time when the state is set.
555 sigqueue_flush(&p->p_sigqueue);
556 sigqueue_flush(&td->td_sigqueue);
559 * We have to wait until after acquiring all locks before
560 * changing p_state. We need to avoid all possible context
561 * switches (including ones from blocking on a mutex) while
562 * marked as a zombie. We also have to set the zombie state
563 * before we release the parent process' proc lock to avoid
564 * a lost wakeup. So, we first call wakeup, then we grab the
565 * sched lock, update the state, and release the parent process'
569 cv_broadcast(&p->p_pwait);
570 sched_exit(p->p_pptr, td);
572 p->p_state = PRS_ZOMBIE;
573 PROC_UNLOCK(p->p_pptr);
576 * Hopefully no one will try to deliver a signal to the process this
579 knlist_destroy(&p->p_klist);
582 * Save our children's rusage information in our exit rusage.
584 ruadd(&p->p_ru, &p->p_rux, &p->p_stats->p_cru, &p->p_crux);
587 * Make sure the scheduler takes this thread out of its tables etc.
588 * This will also release this thread's reference to the ucred.
589 * Other thread parts to release include pcb bits and such.
595 #ifndef _SYS_SYSPROTO_H_
604 sys_abort2(struct thread *td, struct abort2_args *uap)
606 struct proc *p = td->td_proc;
612 * Do it right now so we can log either proper call of abort2(), or
613 * note, that invalid argument was passed. 512 is big enough to
614 * handle 16 arguments' descriptions with additional comments.
616 sb = sbuf_new(NULL, NULL, 512, SBUF_FIXEDLEN);
618 sbuf_printf(sb, "%s(pid %d uid %d) aborted: ",
619 p->p_comm, p->p_pid, td->td_ucred->cr_uid);
621 * Since we can't return from abort2(), send SIGKILL in cases, where
622 * abort2() was called improperly
625 /* Prevent from DoSes from user-space. */
626 if (uap->nargs < 0 || uap->nargs > 16)
628 if (uap->nargs > 0) {
629 if (uap->args == NULL)
631 error = copyin(uap->args, uargs, uap->nargs * sizeof(void *));
636 * Limit size of 'reason' string to 128. Will fit even when
637 * maximal number of arguments was chosen to be logged.
639 if (uap->why != NULL) {
640 error = sbuf_copyin(sb, uap->why, 128);
644 sbuf_printf(sb, "(null)");
646 if (uap->nargs > 0) {
647 sbuf_printf(sb, "(");
648 for (i = 0;i < uap->nargs; i++)
649 sbuf_printf(sb, "%s%p", i == 0 ? "" : ", ", uargs[i]);
650 sbuf_printf(sb, ")");
653 * Final stage: arguments were proper, string has been
654 * successfully copied from userspace, and copying pointers
655 * from user-space succeed.
659 if (sig == SIGKILL) {
661 sbuf_printf(sb, " (Reason text inaccessible)");
665 log(LOG_INFO, "%s", sbuf_data(sb));
667 exit1(td, W_EXITCODE(0, sig));
674 * The dirty work is handled by kern_wait().
677 owait(struct thread *td, struct owait_args *uap __unused)
681 error = kern_wait(td, WAIT_ANY, &status, 0, NULL);
683 td->td_retval[1] = status;
686 #endif /* COMPAT_43 */
689 * The dirty work is handled by kern_wait().
692 sys_wait4(struct thread *td, struct wait4_args *uap)
694 struct rusage ru, *rup;
697 if (uap->rusage != NULL)
701 error = kern_wait(td, uap->pid, &status, uap->options, rup);
702 if (uap->status != NULL && error == 0)
703 error = copyout(&status, uap->status, sizeof(status));
704 if (uap->rusage != NULL && error == 0)
705 error = copyout(&ru, uap->rusage, sizeof(struct rusage));
710 sys_wait6(struct thread *td, struct wait6_args *uap)
712 struct __wrusage wru, *wrup;
718 idtype = uap->idtype;
721 if (uap->wrusage != NULL)
726 if (uap->info != NULL) {
728 bzero(sip, sizeof(*sip));
733 * We expect all callers of wait6() to know about WEXITED and
736 error = kern_wait6(td, idtype, id, &status, uap->options, wrup, sip);
738 if (uap->status != NULL && error == 0)
739 error = copyout(&status, uap->status, sizeof(status));
740 if (uap->wrusage != NULL && error == 0)
741 error = copyout(&wru, uap->wrusage, sizeof(wru));
742 if (uap->info != NULL && error == 0)
743 error = copyout(&si, uap->info, sizeof(si));
748 * Reap the remains of a zombie process and optionally return status and
749 * rusage. Asserts and will release both the proctree_lock and the process
750 * lock as part of its work.
753 proc_reap(struct thread *td, struct proc *p, int *status, int options)
757 sx_assert(&proctree_lock, SA_XLOCKED);
758 PROC_LOCK_ASSERT(p, MA_OWNED);
759 PROC_SLOCK_ASSERT(p, MA_OWNED);
760 KASSERT(p->p_state == PRS_ZOMBIE, ("proc_reap: !PRS_ZOMBIE"));
765 td->td_retval[0] = p->p_pid;
767 *status = p->p_xstat; /* convert to int */
768 if (options & WNOWAIT) {
770 * Only poll, returning the status. Caller does not wish to
771 * release the proc struct just yet.
774 sx_xunlock(&proctree_lock);
779 sigqueue_take(p->p_ksi);
784 * If we got the child via a ptrace 'attach', we need to give it back
787 if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) {
792 pksignal(t, SIGCHLD, p->p_ksi);
794 cv_broadcast(&p->p_pwait);
796 sx_xunlock(&proctree_lock);
801 * Remove other references to this process to ensure we have an
802 * exclusive reference.
804 sx_xlock(&allproc_lock);
805 LIST_REMOVE(p, p_list); /* off zombproc */
806 sx_xunlock(&allproc_lock);
807 LIST_REMOVE(p, p_sibling);
813 if (p->p_procdesc != NULL)
816 sx_xunlock(&proctree_lock);
819 * As a side effect of this lock, we know that all other writes to
820 * this proc are visible now, so no more locking is needed for p.
823 p->p_xstat = 0; /* XXX: why? */
826 ruadd(&q->p_stats->p_cru, &q->p_crux, &p->p_ru, &p->p_rux);
830 * Decrement the count of procs running with this uid.
832 (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0);
835 * Destroy resource accounting information associated with the process.
839 racct_sub(p, RACCT_NPROC, 1);
845 * Free credentials, arguments, and sigacts.
849 pargs_drop(p->p_args);
851 sigacts_free(p->p_sigacts);
855 * Do any thread-system specific cleanups.
860 * Give vm and machine-dependent layer a chance to free anything that
861 * cpu_exit couldn't release while still running in process context.
867 KASSERT(FIRST_THREAD_IN_PROC(p),
868 ("proc_reap: no residual thread!"));
869 uma_zfree(proc_zone, p);
870 sx_xlock(&allproc_lock);
872 sx_xunlock(&allproc_lock);
876 proc_to_reap(struct thread *td, struct proc *p, idtype_t idtype, id_t id,
877 int *status, int options, struct __wrusage *wrusage, siginfo_t *siginfo)
882 sx_assert(&proctree_lock, SA_XLOCKED);
891 if (p->p_pid != (pid_t)id) {
897 if (p->p_pgid != (pid_t)id) {
903 if (p->p_session->s_sid != (pid_t)id) {
909 if (p->p_ucred->cr_uid != (uid_t)id) {
915 if (p->p_ucred->cr_gid != (gid_t)id) {
921 if (p->p_ucred->cr_prison == NULL ||
922 (p->p_ucred->cr_prison->pr_id != (int)id)) {
928 * It seems that the thread structures get zeroed out
929 * at process exit. This makes it impossible to
930 * support P_SETID, P_CID or P_CPUID.
937 if (p_canwait(td, p)) {
942 if (((options & WEXITED) == 0) && (p->p_state == PRS_ZOMBIE)) {
948 * This special case handles a kthread spawned by linux_clone
949 * (see linux_misc.c). The linux_wait4 and linux_waitpid
950 * functions need to be able to distinguish between waiting
951 * on a process and waiting on a thread. It is a thread if
952 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option
953 * signifies we want to wait for threads and not processes.
955 if ((p->p_sigparent != SIGCHLD) ^
956 ((options & WLINUXCLONE) != 0)) {
963 if (siginfo != NULL) {
964 bzero(siginfo, sizeof(*siginfo));
965 siginfo->si_errno = 0;
968 * SUSv4 requires that the si_signo value is always
969 * SIGCHLD. Obey it despite the rfork(2) interface
970 * allows to request other signal for child exit
973 siginfo->si_signo = SIGCHLD;
976 * This is still a rough estimate. We will fix the
977 * cases TRAPPED, STOPPED, and CONTINUED later.
979 if (WCOREDUMP(p->p_xstat))
980 siginfo->si_code = CLD_DUMPED;
981 else if (WIFSIGNALED(p->p_xstat))
982 siginfo->si_code = CLD_KILLED;
984 siginfo->si_code = CLD_EXITED;
986 siginfo->si_pid = p->p_pid;
987 siginfo->si_uid = p->p_ucred->cr_uid;
988 siginfo->si_status = p->p_xstat;
991 * The si_addr field would be useful additional
992 * detail, but apparently the PC value may be lost
993 * when we reach this point. bzero() above sets
994 * siginfo->si_addr to NULL.
999 * There should be no reason to limit resources usage info to
1000 * exited processes only. A snapshot about any resources used
1001 * by a stopped process may be exactly what is needed.
1003 if (wrusage != NULL) {
1004 rup = &wrusage->wru_self;
1006 calcru(p, &rup->ru_utime, &rup->ru_stime);
1008 rup = &wrusage->wru_children;
1009 *rup = p->p_stats->p_cru;
1010 calccru(p, &rup->ru_utime, &rup->ru_stime);
1013 if (p->p_state == PRS_ZOMBIE) {
1014 proc_reap(td, p, status, options);
1023 kern_wait(struct thread *td, pid_t pid, int *status, int options,
1024 struct rusage *rusage)
1026 struct __wrusage wru, *wrup;
1032 if (pid == WAIT_ANY) {
1035 } else if (pid == WAIT_MYPGRP) {
1039 id = (id_t)q->p_pgid;
1041 } else if (pid < 0) {
1053 * For backward compatibility we implicitly add flags WEXITED
1054 * and WTRAPPED here.
1056 options |= WEXITED | WTRAPPED;
1057 ret = kern_wait6(td, idtype, id, status, options, wrup, NULL);
1059 *rusage = wru.wru_self;
1064 kern_wait6(struct thread *td, idtype_t idtype, id_t id, int *status,
1065 int options, struct __wrusage *wrusage, siginfo_t *siginfo)
1068 int error, nfound, ret;
1070 AUDIT_ARG_VALUE((int)idtype); /* XXX - This is likely wrong! */
1071 AUDIT_ARG_PID((pid_t)id); /* XXX - This may be wrong! */
1072 AUDIT_ARG_VALUE(options);
1076 if ((pid_t)id == WAIT_MYPGRP && (idtype == P_PID || idtype == P_PGID)) {
1077 id = (id_t)q->p_pgid;
1081 /* If we don't know the option, just return. */
1082 if ((options & ~(WUNTRACED | WNOHANG | WCONTINUED | WNOWAIT |
1083 WEXITED | WTRAPPED | WLINUXCLONE)) != 0)
1085 if ((options & (WEXITED | WUNTRACED | WCONTINUED | WTRAPPED)) == 0) {
1087 * We will be unable to find any matching processes,
1088 * because there are no known events to look for.
1089 * Prefer to return error instead of blocking
1096 if (q->p_flag & P_STATCHILD) {
1098 q->p_flag &= ~P_STATCHILD;
1102 sx_xlock(&proctree_lock);
1103 LIST_FOREACH(p, &q->p_children, p_sibling) {
1104 ret = proc_to_reap(td, p, idtype, id, status, options,
1116 if ((options & WTRAPPED) != 0 &&
1117 (p->p_flag & P_TRACED) != 0 &&
1118 (p->p_flag & (P_STOPPED_TRACE | P_STOPPED_SIG)) != 0 &&
1119 (p->p_suspcount == p->p_numthreads) &&
1120 ((p->p_flag & P_WAITED) == 0)) {
1122 if ((options & WNOWAIT) == 0)
1123 p->p_flag |= P_WAITED;
1124 sx_xunlock(&proctree_lock);
1125 td->td_retval[0] = p->p_pid;
1128 *status = W_STOPCODE(p->p_xstat);
1129 if (siginfo != NULL) {
1130 siginfo->si_status = p->p_xstat;
1131 siginfo->si_code = CLD_TRAPPED;
1133 if ((options & WNOWAIT) == 0) {
1135 sigqueue_take(p->p_ksi);
1142 if ((options & WUNTRACED) != 0 &&
1143 (p->p_flag & P_STOPPED_SIG) != 0 &&
1144 (p->p_suspcount == p->p_numthreads) &&
1145 ((p->p_flag & P_WAITED) == 0)) {
1147 if ((options & WNOWAIT) == 0)
1148 p->p_flag |= P_WAITED;
1149 sx_xunlock(&proctree_lock);
1150 td->td_retval[0] = p->p_pid;
1153 *status = W_STOPCODE(p->p_xstat);
1154 if (siginfo != NULL) {
1155 siginfo->si_status = p->p_xstat;
1156 siginfo->si_code = CLD_STOPPED;
1158 if ((options & WNOWAIT) == 0) {
1160 sigqueue_take(p->p_ksi);
1168 if ((options & WCONTINUED) != 0 &&
1169 (p->p_flag & P_CONTINUED) != 0) {
1170 sx_xunlock(&proctree_lock);
1171 td->td_retval[0] = p->p_pid;
1172 if ((options & WNOWAIT) == 0) {
1173 p->p_flag &= ~P_CONTINUED;
1175 sigqueue_take(p->p_ksi);
1182 if (siginfo != NULL) {
1183 siginfo->si_status = SIGCONT;
1184 siginfo->si_code = CLD_CONTINUED;
1192 * Look in the orphans list too, to allow the parent to
1193 * collect it's child exit status even if child is being
1196 * Debugger detaches from the parent upon successful
1197 * switch-over from parent to child. At this point due to
1198 * re-parenting the parent loses the child to debugger and a
1199 * wait4(2) call would report that it has no children to wait
1200 * for. By maintaining a list of orphans we allow the parent
1201 * to successfully wait until the child becomes a zombie.
1203 LIST_FOREACH(p, &q->p_orphans, p_orphan) {
1204 ret = proc_to_reap(td, p, idtype, id, status, options,
1214 sx_xunlock(&proctree_lock);
1217 if (options & WNOHANG) {
1218 sx_xunlock(&proctree_lock);
1219 td->td_retval[0] = 0;
1223 sx_xunlock(&proctree_lock);
1224 if (q->p_flag & P_STATCHILD) {
1225 q->p_flag &= ~P_STATCHILD;
1228 error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0);
1236 * Make process 'parent' the new parent of process 'child'.
1237 * Must be called with an exclusive hold of proctree lock.
1240 proc_reparent(struct proc *child, struct proc *parent)
1243 sx_assert(&proctree_lock, SX_XLOCKED);
1244 PROC_LOCK_ASSERT(child, MA_OWNED);
1245 if (child->p_pptr == parent)
1248 PROC_LOCK(child->p_pptr);
1249 sigqueue_take(child->p_ksi);
1250 PROC_UNLOCK(child->p_pptr);
1251 LIST_REMOVE(child, p_sibling);
1252 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
1254 clear_orphan(child);
1255 if (child->p_flag & P_TRACED) {
1256 LIST_INSERT_HEAD(&child->p_pptr->p_orphans, child, p_orphan);
1257 child->p_flag |= P_ORPHAN;
1260 child->p_pptr = parent;