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
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.
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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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18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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_ktrace.h"
42 #include "opt_procdesc.h"
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/sysproto.h>
47 #include <sys/capability.h>
48 #include <sys/eventhandler.h>
49 #include <sys/kernel.h>
50 #include <sys/malloc.h>
52 #include <sys/mutex.h>
54 #include <sys/procdesc.h>
55 #include <sys/pioctl.h>
59 #include <sys/vmmeter.h>
60 #include <sys/vnode.h>
61 #include <sys/racct.h>
62 #include <sys/resourcevar.h>
64 #include <sys/signalvar.h>
65 #include <sys/sched.h>
67 #include <sys/syscallsubr.h>
68 #include <sys/syslog.h>
69 #include <sys/ptrace.h>
70 #include <sys/acct.h> /* for acct_process() function prototype */
71 #include <sys/filedesc.h>
76 #include <sys/ktrace.h>
79 #include <security/audit/audit.h>
80 #include <security/mac/mac_framework.h>
83 #include <vm/vm_extern.h>
84 #include <vm/vm_param.h>
86 #include <vm/vm_map.h>
87 #include <vm/vm_page.h>
91 #include <sys/dtrace_bsd.h>
92 dtrace_execexit_func_t dtrace_fasttrap_exit;
95 SDT_PROVIDER_DECLARE(proc);
96 SDT_PROBE_DEFINE1(proc, kernel, , exit, "int");
98 /* Hook for NFS teardown procedure. */
99 void (*nlminfo_release_p)(struct proc *p);
102 clear_orphan(struct proc *p)
105 PROC_LOCK_ASSERT(p, MA_OWNED);
107 if (p->p_flag & P_ORPHAN) {
108 LIST_REMOVE(p, p_orphan);
109 p->p_flag &= ~P_ORPHAN;
114 * exit -- death of process.
117 sys_sys_exit(struct thread *td, struct sys_exit_args *uap)
120 exit1(td, W_EXITCODE(uap->rval, 0));
125 * Exit: deallocate address space and other resources, change proc state to
126 * zombie, and unlink proc from allproc and parent's lists. Save exit status
127 * and rusage for wait(). Check for child processes and orphan them.
130 exit1(struct thread *td, int rv)
132 struct proc *p, *nq, *q;
134 struct vnode *ttyvp = NULL;
137 mtx_assert(&Giant, MA_NOTOWNED);
141 * XXX in case we're rebooting we just let init die in order to
142 * work around an unsolved stack overflow seen very late during
143 * shutdown on sparc64 when the gmirror worker process exists.
145 if (p == initproc && rebooting == 0) {
146 printf("init died (signal %d, exit %d)\n",
147 WTERMSIG(rv), WEXITSTATUS(rv));
148 panic("Going nowhere without my init!");
152 * MUST abort all other threads before proceeding past here.
155 while (p->p_flag & P_HADTHREADS) {
157 * First check if some other thread got here before us.
158 * If so, act appropriately: exit or suspend.
160 thread_suspend_check(0);
163 * Kill off the other threads. This requires
164 * some co-operation from other parts of the kernel
165 * so it may not be instantaneous. With this state set
166 * any thread entering the kernel from userspace will
167 * thread_exit() in trap(). Any thread attempting to
168 * sleep will return immediately with EINTR or EWOULDBLOCK
169 * which will hopefully force them to back out to userland
170 * freeing resources as they go. Any thread attempting
171 * to return to userland will thread_exit() from userret().
172 * thread_exit() will unsuspend us when the last of the
173 * other threads exits.
174 * If there is already a thread singler after resumption,
175 * calling thread_single will fail; in that case, we just
176 * re-check all suspension request, the thread should
177 * either be suspended there or exit.
179 if (!thread_single(SINGLE_EXIT))
183 * All other activity in this process is now stopped.
184 * Threading support has been turned off.
187 KASSERT(p->p_numthreads == 1,
188 ("exit1: proc %p exiting with %d threads", p, p->p_numthreads));
189 racct_sub(p, RACCT_NTHR, 1);
191 * Wakeup anyone in procfs' PIOCWAIT. They should have a hold
192 * on our vmspace, so we should block below until they have
193 * released their reference to us. Note that if they have
194 * requested S_EXIT stops we will block here until they ack
197 _STOPEVENT(p, S_EXIT, rv);
200 * Ignore any pending request to stop due to a stop signal.
201 * Once P_WEXIT is set, future requests will be ignored as
204 p->p_flag &= ~P_STOPPED_SIG;
205 KASSERT(!P_SHOULDSTOP(p), ("exiting process is stopped"));
208 * Note that we are exiting and do another wakeup of anyone in
209 * PIOCWAIT in case they aren't listening for S_EXIT stops or
210 * decided to wait again after we told them we are exiting.
212 p->p_flag |= P_WEXIT;
216 * Wait for any processes that have a hold on our vmspace to
217 * release their reference.
219 while (p->p_lock > 0)
220 msleep(&p->p_lock, &p->p_mtx, PWAIT, "exithold", 0);
222 p->p_xstat = rv; /* Let event handler change exit status */
224 /* Drain the limit callout while we don't have the proc locked */
225 callout_drain(&p->p_limco);
229 * The Sun BSM exit token contains two components: an exit status as
230 * passed to exit(), and a return value to indicate what sort of exit
231 * it was. The exit status is WEXITSTATUS(rv), but it's not clear
232 * what the return value is.
234 AUDIT_ARG_EXIT(WEXITSTATUS(rv), 0);
235 AUDIT_SYSCALL_EXIT(0, td);
238 /* Are we a task leader? */
239 if (p == p->p_leader) {
240 mtx_lock(&ppeers_lock);
244 kern_psignal(q, SIGKILL);
248 while (p->p_peers != NULL)
249 msleep(p, &ppeers_lock, PWAIT, "exit1", 0);
250 mtx_unlock(&ppeers_lock);
254 * Check if any loadable modules need anything done at process exit.
255 * E.g. SYSV IPC stuff
256 * XXX what if one of these generates an error?
258 EVENTHANDLER_INVOKE(process_exit, p);
261 * If parent is waiting for us to exit or exec,
262 * P_PPWAIT is set; we will wakeup the parent below.
265 rv = p->p_xstat; /* Event handler could change exit status */
267 p->p_flag &= ~(P_TRACED | P_PPWAIT | P_PPTRACE);
270 * Stop the real interval timer. If the handler is currently
271 * executing, prevent it from rearming itself and let it finish.
273 if (timevalisset(&p->p_realtimer.it_value) &&
274 callout_stop(&p->p_itcallout) == 0) {
275 timevalclear(&p->p_realtimer.it_interval);
276 msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0);
277 KASSERT(!timevalisset(&p->p_realtimer.it_value),
278 ("realtime timer is still armed"));
283 * Reset any sigio structures pointing to us as a result of
284 * F_SETOWN with our pid.
286 funsetownlst(&p->p_sigiolst);
289 * If this process has an nlminfo data area (for lockd), release it
291 if (nlminfo_release_p != NULL && p->p_nlminfo != NULL)
292 (*nlminfo_release_p)(p);
295 * Close open files and release open-file table.
301 * If this thread tickled GEOM, we need to wait for the giggling to
302 * stop before we return to userland
304 if (td->td_pflags & TDP_GEOM)
308 * Remove ourself from our leader's peer list and wake our leader.
310 mtx_lock(&ppeers_lock);
311 if (p->p_leader->p_peers) {
313 while (q->p_peers != p)
315 q->p_peers = p->p_peers;
318 mtx_unlock(&ppeers_lock);
322 sx_xlock(&proctree_lock);
323 if (SESS_LEADER(p)) {
324 struct session *sp = p->p_session;
328 * s_ttyp is not zero'd; we use this to indicate that
329 * the session once had a controlling terminal. (for
330 * logging and informational purposes)
341 * Signal foreground pgrp and revoke access to
342 * controlling terminal if it has not been revoked
345 * Because the TTY may have been revoked in the mean
346 * time and could already have a new session associated
347 * with it, make sure we don't send a SIGHUP to a
348 * foreground process group that does not belong to this
354 if (tp->t_session == sp)
355 tty_signal_pgrp(tp, SIGHUP);
360 sx_xunlock(&proctree_lock);
361 if (vn_lock(ttyvp, LK_EXCLUSIVE) == 0) {
362 VOP_REVOKE(ttyvp, REVOKEALL);
363 VOP_UNLOCK(ttyvp, 0);
365 sx_xlock(&proctree_lock);
368 fixjobc(p, p->p_pgrp, 0);
369 sx_xunlock(&proctree_lock);
370 (void)acct_process(td);
372 /* Release the TTY now we've unlocked everything. */
379 * Release reference to text vnode
381 if ((vtmp = p->p_textvp) != NULL) {
387 * Release our limits structure.
398 * Remove proc from allproc queue and pidhash chain.
399 * Place onto zombproc. Unlink from parent's child list.
401 sx_xlock(&allproc_lock);
402 LIST_REMOVE(p, p_list);
403 LIST_INSERT_HEAD(&zombproc, p, p_list);
404 LIST_REMOVE(p, p_hash);
405 sx_xunlock(&allproc_lock);
408 * Call machine-dependent code to release any
409 * machine-dependent resources other than the address space.
410 * The address space is released by "vmspace_exitfree(p)" in
415 WITNESS_WARN(WARN_PANIC, NULL, "process (pid %d) exiting", p->p_pid);
418 * Reparent all of our children to init.
420 sx_xlock(&proctree_lock);
421 q = LIST_FIRST(&p->p_children);
422 if (q != NULL) /* only need this if any child is S_ZOMB */
424 for (; q != NULL; q = nq) {
425 nq = LIST_NEXT(q, p_sibling);
427 proc_reparent(q, initproc);
428 q->p_sigparent = SIGCHLD;
430 * Traced processes are killed
431 * since their existence means someone is screwing up.
433 if (q->p_flag & P_TRACED) {
437 * Since q was found on our children list, the
438 * proc_reparent() call moved q to the orphan
439 * list due to present P_TRACED flag. Clear
440 * orphan link for q now while q is locked.
443 q->p_flag &= ~(P_TRACED | P_STOPPED_TRACE);
444 FOREACH_THREAD_IN_PROC(q, temp)
445 temp->td_dbgflags &= ~TDB_SUSPEND;
446 kern_psignal(q, SIGKILL);
452 * Also get rid of our orphans.
454 while ((q = LIST_FIRST(&p->p_orphans)) != NULL) {
460 /* Save exit status. */
464 /* Tell the prison that we are gone. */
465 prison_proc_free(p->p_ucred->cr_prison);
469 * Tell the DTrace fasttrap provider about the exit if it
470 * has declared an interest.
472 if (dtrace_fasttrap_exit)
473 dtrace_fasttrap_exit(p);
477 * Notify interested parties of our demise.
479 KNOTE_LOCKED(&p->p_klist, NOTE_EXIT);
482 int reason = CLD_EXITED;
485 else if (WIFSIGNALED(rv))
487 SDT_PROBE(proc, kernel, , exit, reason, 0, 0, 0, 0);
491 * Just delete all entries in the p_klist. At this point we won't
492 * report any more events, and there are nasty race conditions that
493 * can beat us if we don't.
495 knlist_clear(&p->p_klist, 1);
498 * If this is a process with a descriptor, we may not need to deliver
499 * a signal to the parent. proctree_lock is held over
500 * procdesc_exit() to serialize concurrent calls to close() and
504 if (p->p_procdesc == NULL || procdesc_exit(p)) {
507 * Notify parent that we're gone. If parent has the
508 * PS_NOCLDWAIT flag set, or if the handler is set to SIG_IGN,
509 * notify process 1 instead (and hope it will handle this
512 PROC_LOCK(p->p_pptr);
513 mtx_lock(&p->p_pptr->p_sigacts->ps_mtx);
514 if (p->p_pptr->p_sigacts->ps_flag &
515 (PS_NOCLDWAIT | PS_CLDSIGIGN)) {
518 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
521 proc_reparent(p, initproc);
522 p->p_sigparent = SIGCHLD;
523 PROC_LOCK(p->p_pptr);
526 * Notify parent, so in case he was wait(2)ing or
527 * executing waitpid(2) with our pid, he will
532 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
534 if (p->p_pptr == initproc)
535 kern_psignal(p->p_pptr, SIGCHLD);
536 else if (p->p_sigparent != 0) {
537 if (p->p_sigparent == SIGCHLD)
539 else /* LINUX thread */
540 kern_psignal(p->p_pptr, p->p_sigparent);
544 PROC_LOCK(p->p_pptr);
546 sx_xunlock(&proctree_lock);
549 * The state PRS_ZOMBIE prevents other proesses from sending
550 * signal to the process, to avoid memory leak, we free memory
551 * for signal queue at the time when the state is set.
553 sigqueue_flush(&p->p_sigqueue);
554 sigqueue_flush(&td->td_sigqueue);
557 * We have to wait until after acquiring all locks before
558 * changing p_state. We need to avoid all possible context
559 * switches (including ones from blocking on a mutex) while
560 * marked as a zombie. We also have to set the zombie state
561 * before we release the parent process' proc lock to avoid
562 * a lost wakeup. So, we first call wakeup, then we grab the
563 * sched lock, update the state, and release the parent process'
567 cv_broadcast(&p->p_pwait);
568 sched_exit(p->p_pptr, td);
570 p->p_state = PRS_ZOMBIE;
571 PROC_UNLOCK(p->p_pptr);
574 * Hopefully no one will try to deliver a signal to the process this
577 knlist_destroy(&p->p_klist);
580 * Save our children's rusage information in our exit rusage.
582 ruadd(&p->p_ru, &p->p_rux, &p->p_stats->p_cru, &p->p_crux);
585 * Make sure the scheduler takes this thread out of its tables etc.
586 * This will also release this thread's reference to the ucred.
587 * Other thread parts to release include pcb bits and such.
593 #ifndef _SYS_SYSPROTO_H_
602 sys_abort2(struct thread *td, struct abort2_args *uap)
604 struct proc *p = td->td_proc;
610 * Do it right now so we can log either proper call of abort2(), or
611 * note, that invalid argument was passed. 512 is big enough to
612 * handle 16 arguments' descriptions with additional comments.
614 sb = sbuf_new(NULL, NULL, 512, SBUF_FIXEDLEN);
616 sbuf_printf(sb, "%s(pid %d uid %d) aborted: ",
617 p->p_comm, p->p_pid, td->td_ucred->cr_uid);
619 * Since we can't return from abort2(), send SIGKILL in cases, where
620 * abort2() was called improperly
623 /* Prevent from DoSes from user-space. */
624 if (uap->nargs < 0 || uap->nargs > 16)
626 if (uap->nargs > 0) {
627 if (uap->args == NULL)
629 error = copyin(uap->args, uargs, uap->nargs * sizeof(void *));
634 * Limit size of 'reason' string to 128. Will fit even when
635 * maximal number of arguments was chosen to be logged.
637 if (uap->why != NULL) {
638 error = sbuf_copyin(sb, uap->why, 128);
642 sbuf_printf(sb, "(null)");
644 if (uap->nargs > 0) {
645 sbuf_printf(sb, "(");
646 for (i = 0;i < uap->nargs; i++)
647 sbuf_printf(sb, "%s%p", i == 0 ? "" : ", ", uargs[i]);
648 sbuf_printf(sb, ")");
651 * Final stage: arguments were proper, string has been
652 * successfully copied from userspace, and copying pointers
653 * from user-space succeed.
657 if (sig == SIGKILL) {
659 sbuf_printf(sb, " (Reason text inaccessible)");
663 log(LOG_INFO, "%s", sbuf_data(sb));
665 exit1(td, W_EXITCODE(0, sig));
672 * The dirty work is handled by kern_wait().
675 owait(struct thread *td, struct owait_args *uap __unused)
679 error = kern_wait(td, WAIT_ANY, &status, 0, NULL);
681 td->td_retval[1] = status;
684 #endif /* COMPAT_43 */
687 * The dirty work is handled by kern_wait().
690 sys_wait4(struct thread *td, struct wait4_args *uap)
692 struct rusage ru, *rup;
695 if (uap->rusage != NULL)
699 error = kern_wait(td, uap->pid, &status, uap->options, rup);
700 if (uap->status != NULL && error == 0)
701 error = copyout(&status, uap->status, sizeof(status));
702 if (uap->rusage != NULL && error == 0)
703 error = copyout(&ru, uap->rusage, sizeof(struct rusage));
708 sys_wait6(struct thread *td, struct wait6_args *uap)
710 struct __wrusage wru, *wrup;
716 idtype = uap->idtype;
719 if (uap->wrusage != NULL)
724 if (uap->info != NULL) {
726 bzero(sip, sizeof(*sip));
731 * We expect all callers of wait6() to know about WEXITED and
734 error = kern_wait6(td, idtype, id, &status, uap->options, wrup, sip);
736 if (uap->status != NULL && error == 0)
737 error = copyout(&status, uap->status, sizeof(status));
738 if (uap->wrusage != NULL && error == 0)
739 error = copyout(&wru, uap->wrusage, sizeof(wru));
740 if (uap->info != NULL && error == 0)
741 error = copyout(&si, uap->info, sizeof(si));
746 * Reap the remains of a zombie process and optionally return status and
747 * rusage. Asserts and will release both the proctree_lock and the process
748 * lock as part of its work.
751 proc_reap(struct thread *td, struct proc *p, int *status, int options)
755 sx_assert(&proctree_lock, SA_XLOCKED);
756 PROC_LOCK_ASSERT(p, MA_OWNED);
757 PROC_SLOCK_ASSERT(p, MA_OWNED);
758 KASSERT(p->p_state == PRS_ZOMBIE, ("proc_reap: !PRS_ZOMBIE"));
763 td->td_retval[0] = p->p_pid;
765 *status = p->p_xstat; /* convert to int */
766 if (options & WNOWAIT) {
768 * Only poll, returning the status. Caller does not wish to
769 * release the proc struct just yet.
772 sx_xunlock(&proctree_lock);
777 sigqueue_take(p->p_ksi);
782 * If we got the child via a ptrace 'attach', we need to give it back
785 if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) {
790 pksignal(t, SIGCHLD, p->p_ksi);
792 cv_broadcast(&p->p_pwait);
794 sx_xunlock(&proctree_lock);
799 * Remove other references to this process to ensure we have an
800 * exclusive reference.
802 sx_xlock(&allproc_lock);
803 LIST_REMOVE(p, p_list); /* off zombproc */
804 sx_xunlock(&allproc_lock);
805 LIST_REMOVE(p, p_sibling);
811 if (p->p_procdesc != NULL)
814 sx_xunlock(&proctree_lock);
817 * As a side effect of this lock, we know that all other writes to
818 * this proc are visible now, so no more locking is needed for p.
821 p->p_xstat = 0; /* XXX: why? */
824 ruadd(&q->p_stats->p_cru, &q->p_crux, &p->p_ru, &p->p_rux);
828 * Decrement the count of procs running with this uid.
830 (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0);
833 * Destroy resource accounting information associated with the process.
837 racct_sub(p, RACCT_NPROC, 1);
843 * Free credentials, arguments, and sigacts.
847 pargs_drop(p->p_args);
849 sigacts_free(p->p_sigacts);
853 * Do any thread-system specific cleanups.
858 * Give vm and machine-dependent layer a chance to free anything that
859 * cpu_exit couldn't release while still running in process context.
865 KASSERT(FIRST_THREAD_IN_PROC(p),
866 ("proc_reap: no residual thread!"));
867 uma_zfree(proc_zone, p);
868 sx_xlock(&allproc_lock);
870 sx_xunlock(&allproc_lock);
874 proc_to_reap(struct thread *td, struct proc *p, idtype_t idtype, id_t id,
875 int *status, int options, struct __wrusage *wrusage, siginfo_t *siginfo)
880 sx_assert(&proctree_lock, SA_XLOCKED);
889 if (p->p_pid != (pid_t)id) {
895 if (p->p_pgid != (pid_t)id) {
901 if (p->p_session->s_sid != (pid_t)id) {
907 if (p->p_ucred->cr_uid != (uid_t)id) {
913 if (p->p_ucred->cr_gid != (gid_t)id) {
919 if (p->p_ucred->cr_prison->pr_id != (int)id) {
925 * It seems that the thread structures get zeroed out
926 * at process exit. This makes it impossible to
927 * support P_SETID, P_CID or P_CPUID.
934 if (p_canwait(td, p)) {
939 if (((options & WEXITED) == 0) && (p->p_state == PRS_ZOMBIE)) {
945 * This special case handles a kthread spawned by linux_clone
946 * (see linux_misc.c). The linux_wait4 and linux_waitpid
947 * functions need to be able to distinguish between waiting
948 * on a process and waiting on a thread. It is a thread if
949 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option
950 * signifies we want to wait for threads and not processes.
952 if ((p->p_sigparent != SIGCHLD) ^
953 ((options & WLINUXCLONE) != 0)) {
960 if (siginfo != NULL) {
961 bzero(siginfo, sizeof(*siginfo));
962 siginfo->si_errno = 0;
965 * SUSv4 requires that the si_signo value is always
966 * SIGCHLD. Obey it despite the rfork(2) interface
967 * allows to request other signal for child exit
970 siginfo->si_signo = SIGCHLD;
973 * This is still a rough estimate. We will fix the
974 * cases TRAPPED, STOPPED, and CONTINUED later.
976 if (WCOREDUMP(p->p_xstat)) {
977 siginfo->si_code = CLD_DUMPED;
978 siginfo->si_status = WTERMSIG(p->p_xstat);
979 } else if (WIFSIGNALED(p->p_xstat)) {
980 siginfo->si_code = CLD_KILLED;
981 siginfo->si_status = WTERMSIG(p->p_xstat);
983 siginfo->si_code = CLD_EXITED;
984 siginfo->si_status = WEXITSTATUS(p->p_xstat);
987 siginfo->si_pid = p->p_pid;
988 siginfo->si_uid = p->p_ucred->cr_uid;
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 * Translate the special pid values into the (idtype, pid)
1033 * pair for kern_wait6. The WAIT_MYPGRP case is handled by
1034 * kern_wait6() on its own.
1036 if (pid == WAIT_ANY) {
1039 } 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)) {
1078 id = (id_t)q->p_pgid;
1083 /* If we don't know the option, just return. */
1084 if ((options & ~(WUNTRACED | WNOHANG | WCONTINUED | WNOWAIT |
1085 WEXITED | WTRAPPED | WLINUXCLONE)) != 0)
1087 if ((options & (WEXITED | WUNTRACED | WCONTINUED | WTRAPPED)) == 0) {
1089 * We will be unable to find any matching processes,
1090 * because there are no known events to look for.
1091 * Prefer to return error instead of blocking
1098 if (q->p_flag & P_STATCHILD) {
1100 q->p_flag &= ~P_STATCHILD;
1104 sx_xlock(&proctree_lock);
1105 LIST_FOREACH(p, &q->p_children, p_sibling) {
1106 ret = proc_to_reap(td, p, idtype, id, status, options,
1118 if ((options & WTRAPPED) != 0 &&
1119 (p->p_flag & P_TRACED) != 0 &&
1120 (p->p_flag & (P_STOPPED_TRACE | P_STOPPED_SIG)) != 0 &&
1121 (p->p_suspcount == p->p_numthreads) &&
1122 ((p->p_flag & P_WAITED) == 0)) {
1124 if ((options & WNOWAIT) == 0)
1125 p->p_flag |= P_WAITED;
1126 sx_xunlock(&proctree_lock);
1127 td->td_retval[0] = p->p_pid;
1130 *status = W_STOPCODE(p->p_xstat);
1131 if (siginfo != NULL) {
1132 siginfo->si_status = p->p_xstat;
1133 siginfo->si_code = CLD_TRAPPED;
1135 if ((options & WNOWAIT) == 0) {
1137 sigqueue_take(p->p_ksi);
1144 if ((options & WUNTRACED) != 0 &&
1145 (p->p_flag & P_STOPPED_SIG) != 0 &&
1146 (p->p_suspcount == p->p_numthreads) &&
1147 ((p->p_flag & P_WAITED) == 0)) {
1149 if ((options & WNOWAIT) == 0)
1150 p->p_flag |= P_WAITED;
1151 sx_xunlock(&proctree_lock);
1152 td->td_retval[0] = p->p_pid;
1155 *status = W_STOPCODE(p->p_xstat);
1156 if (siginfo != NULL) {
1157 siginfo->si_status = p->p_xstat;
1158 siginfo->si_code = CLD_STOPPED;
1160 if ((options & WNOWAIT) == 0) {
1162 sigqueue_take(p->p_ksi);
1170 if ((options & WCONTINUED) != 0 &&
1171 (p->p_flag & P_CONTINUED) != 0) {
1172 sx_xunlock(&proctree_lock);
1173 td->td_retval[0] = p->p_pid;
1174 if ((options & WNOWAIT) == 0) {
1175 p->p_flag &= ~P_CONTINUED;
1177 sigqueue_take(p->p_ksi);
1184 if (siginfo != NULL) {
1185 siginfo->si_status = SIGCONT;
1186 siginfo->si_code = CLD_CONTINUED;
1194 * Look in the orphans list too, to allow the parent to
1195 * collect it's child exit status even if child is being
1198 * Debugger detaches from the parent upon successful
1199 * switch-over from parent to child. At this point due to
1200 * re-parenting the parent loses the child to debugger and a
1201 * wait4(2) call would report that it has no children to wait
1202 * for. By maintaining a list of orphans we allow the parent
1203 * to successfully wait until the child becomes a zombie.
1205 LIST_FOREACH(p, &q->p_orphans, p_orphan) {
1206 ret = proc_to_reap(td, p, idtype, id, status, options,
1216 sx_xunlock(&proctree_lock);
1219 if (options & WNOHANG) {
1220 sx_xunlock(&proctree_lock);
1221 td->td_retval[0] = 0;
1225 sx_xunlock(&proctree_lock);
1226 if (q->p_flag & P_STATCHILD) {
1227 q->p_flag &= ~P_STATCHILD;
1230 error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0);
1238 * Make process 'parent' the new parent of process 'child'.
1239 * Must be called with an exclusive hold of proctree lock.
1242 proc_reparent(struct proc *child, struct proc *parent)
1245 sx_assert(&proctree_lock, SX_XLOCKED);
1246 PROC_LOCK_ASSERT(child, MA_OWNED);
1247 if (child->p_pptr == parent)
1250 PROC_LOCK(child->p_pptr);
1251 sigqueue_take(child->p_ksi);
1252 PROC_UNLOCK(child->p_pptr);
1253 LIST_REMOVE(child, p_sibling);
1254 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
1256 clear_orphan(child);
1257 if (child->p_flag & P_TRACED) {
1258 LIST_INSERT_HEAD(&child->p_pptr->p_orphans, child, p_orphan);
1259 child->p_flag |= P_ORPHAN;
1262 child->p_pptr = parent;