NetBSD/sys/kern/kern_exit.c

886 lines
22 KiB
C

/* $NetBSD: kern_exit.c,v 1.144 2005/01/24 21:27:02 dbj Exp $ */
/*-
* Copyright (c) 1998, 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1982, 1986, 1989, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_exit.c 8.10 (Berkeley) 2/23/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_exit.c,v 1.144 2005/01/24 21:27:02 dbj Exp $");
#include "opt_ktrace.h"
#include "opt_perfctrs.h"
#include "opt_systrace.h"
#include "opt_sysv.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/kernel.h>
#include <sys/ktrace.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/wait.h>
#include <sys/file.h>
#include <sys/vnode.h>
#include <sys/syslog.h>
#include <sys/malloc.h>
#include <sys/pool.h>
#include <sys/resourcevar.h>
#if defined(PERFCTRS)
#include <sys/pmc.h>
#endif
#include <sys/ptrace.h>
#include <sys/acct.h>
#include <sys/filedesc.h>
#include <sys/ras.h>
#include <sys/signalvar.h>
#include <sys/sched.h>
#include <sys/sa.h>
#include <sys/savar.h>
#include <sys/mount.h>
#include <sys/syscallargs.h>
#include <sys/systrace.h>
#include <machine/cpu.h>
#include <uvm/uvm_extern.h>
#define DEBUG_EXIT
#ifdef DEBUG_EXIT
int debug_exit = 0;
#define DPRINTF(x) if (debug_exit) printf x
#else
#define DPRINTF(x)
#endif
static void lwp_exit_hook(struct lwp *, void *);
/*
* Fill in the appropriate signal information, and signal the parent.
*/
static void
exit_psignal(struct proc *p, struct proc *pp, ksiginfo_t *ksi)
{
(void)memset(ksi, 0, sizeof(ksiginfo_t));
if ((ksi->ksi_signo = P_EXITSIG(p)) == SIGCHLD) {
if (WIFSIGNALED(p->p_xstat)) {
if (WCOREDUMP(p->p_xstat))
ksi->ksi_code = CLD_DUMPED;
else
ksi->ksi_code = CLD_KILLED;
} else {
ksi->ksi_code = CLD_EXITED;
}
}
/*
* we fill those in, even for non-SIGCHLD.
*/
ksi->ksi_pid = p->p_pid;
ksi->ksi_uid = p->p_ucred->cr_uid;
ksi->ksi_status = p->p_xstat;
/* XXX: is this still valid? */
ksi->ksi_utime = p->p_ru->ru_utime.tv_sec;
ksi->ksi_stime = p->p_ru->ru_stime.tv_sec;
}
/*
* exit --
* Death of process.
*/
int
sys_exit(struct lwp *l, void *v, register_t *retval)
{
struct sys_exit_args /* {
syscallarg(int) rval;
} */ *uap = v;
/* Don't call exit1() multiple times in the same process.*/
if (l->l_proc->p_flag & P_WEXIT)
lwp_exit(l);
exit1(l, W_EXITCODE(SCARG(uap, rval), 0));
/* NOTREACHED */
return (0);
}
/*
* Exit: deallocate address space and other resources, change proc state
* to zombie, and unlink proc from allproc and parent's lists. Save exit
* status and rusage for wait(). Check for child processes and orphan them.
*/
void
exit1(struct lwp *l, int rv)
{
struct proc *p, *q, *nq;
int s, sa;
struct plimit *plim;
struct pstats *pstats;
struct sigacts *ps;
ksiginfo_t ksi;
int do_psignal = 0;
p = l->l_proc;
if (__predict_false(p == initproc))
panic("init died (signal %d, exit %d)",
WTERMSIG(rv), WEXITSTATUS(rv));
p->p_flag |= P_WEXIT;
if (p->p_flag & P_STOPEXIT) {
int s;
sigminusset(&contsigmask, &p->p_sigctx.ps_siglist);
SCHED_LOCK(s);
p->p_stat = SSTOP;
l->l_stat = LSSTOP;
p->p_nrlwps--;
mi_switch(l, NULL);
SCHED_ASSERT_UNLOCKED();
splx(s);
}
DPRINTF(("exit1: %d.%d exiting.\n", p->p_pid, l->l_lid));
/*
* Disable scheduler activation upcalls.
* We're trying to get out of here.
*/
sa = 0;
if (p->p_sa != NULL) {
l->l_flag &= ~L_SA;
#if 0
p->p_flag &= ~P_SA;
#endif
sa = 1;
}
#ifdef PGINPROF
vmsizmon();
#endif
if (p->p_flag & P_PROFIL)
stopprofclock(p);
p->p_ru = pool_get(&rusage_pool, PR_WAITOK);
/*
* If parent is waiting for us to exit or exec, P_PPWAIT is set; we
* wake up the parent early to avoid deadlock.
*/
if (p->p_flag & P_PPWAIT) {
p->p_flag &= ~P_PPWAIT;
wakeup(p->p_pptr);
}
sigfillset(&p->p_sigctx.ps_sigignore);
sigemptyset(&p->p_sigctx.ps_siglist);
p->p_sigctx.ps_sigcheck = 0;
timers_free(p, TIMERS_ALL);
if (sa || (p->p_nlwps > 1)) {
exit_lwps(l);
/*
* Collect thread u-areas.
*/
uvm_uarea_drain(FALSE);
}
#if defined(__HAVE_RAS)
ras_purgeall(p);
#endif
/*
* Close open files and release open-file table.
* This may block!
*/
fdfree(p);
cwdfree(p->p_cwdi);
p->p_cwdi = 0;
doexithooks(p);
if (SESS_LEADER(p)) {
struct session *sp = p->p_session;
struct tty *tp;
if (sp->s_ttyvp) {
int s;
/*
* Controlling process.
* Signal foreground pgrp,
* drain controlling terminal
* and revoke access to controlling terminal.
*/
tp = sp->s_ttyp;
s = spltty();
TTY_LOCK(tp);
if (tp->t_session == sp) {
if (tp->t_pgrp)
pgsignal(tp->t_pgrp, SIGHUP, 1);
/* we can't guarantee the revoke will do this */
tp->t_pgrp = NULL;
tp->t_session = NULL;
TTY_UNLOCK(tp);
splx(s);
SESSRELE(sp);
(void) ttywait(tp);
/*
* The tty could have been revoked
* if we blocked.
*/
if (sp->s_ttyvp)
VOP_REVOKE(sp->s_ttyvp, REVOKEALL);
} else {
TTY_UNLOCK(tp);
splx(s);
}
if (sp->s_ttyvp)
vrele(sp->s_ttyvp);
sp->s_ttyvp = NULL;
/*
* s_ttyp is not zero'd; we use this to indicate
* that the session once had a controlling terminal.
* (for logging and informational purposes)
*/
}
sp->s_leader = NULL;
}
fixjobc(p, p->p_pgrp, 0);
(void)acct_process(p);
#ifdef KTRACE
/*
* release trace file
*/
ktrderef(p);
#endif
#ifdef SYSTRACE
systrace_sys_exit(p);
#endif
/*
* If emulation has process exit hook, call it now.
*/
if (p->p_emul->e_proc_exit)
(*p->p_emul->e_proc_exit)(p);
/*
* Free the VM resources we're still holding on to.
* We must do this from a valid thread because doing
* so may block. This frees vmspace, which we don't
* need anymore. The only remaining lwp is the one
* we run at this moment, nothing runs in userland
* anymore.
*/
uvm_proc_exit(p);
/*
* Give machine-dependent code a chance to free any
* MD LWP resources while we can still block. This must be done
* before uvm_lwp_exit(), in case these resources are in the
* PCB.
* THIS IS LAST BLOCKING OPERATION.
*/
#ifndef __NO_CPU_LWP_FREE
cpu_lwp_free(l, 1);
#endif
pmap_deactivate(l);
/*
* NOTE: WE ARE NO LONGER ALLOWED TO SLEEP!
*/
/*
* Save exit status and final rusage info, adding in child rusage
* info and self times.
* In order to pick up the time for the current execution, we must
* do this before unlinking the lwp from l_list.
*/
p->p_xstat = rv;
*p->p_ru = p->p_stats->p_ru;
calcru(p, &p->p_ru->ru_utime, &p->p_ru->ru_stime, NULL);
ruadd(p->p_ru, &p->p_stats->p_cru);
/*
* Notify interested parties of our demise.
*/
KNOTE(&p->p_klist, NOTE_EXIT);
#if PERFCTRS
/*
* Save final PMC information in parent process & clean up.
*/
if (PMC_ENABLED(p)) {
pmc_save_context(p);
pmc_accumulate(p->p_pptr, p);
pmc_process_exit(p);
}
#endif
s = proclist_lock_write();
/*
* Reset p_opptr pointer of all former children which got
* traced by another process and were reparented. We reset
* it to NULL here; the trace detach code then reparents
* the child to initproc. We only check allproc list, since
* eventual former children on zombproc list won't reference
* p_opptr anymore.
*/
if (p->p_flag & P_CHTRACED) {
PROCLIST_FOREACH(q, &allproc) {
if (q->p_opptr == p)
q->p_opptr = NULL;
}
}
/*
* Give orphaned children to init(8).
*/
q = LIST_FIRST(&p->p_children);
if (q) /* only need this if any child is SZOMB */
wakeup(initproc);
for (; q != NULL; q = nq) {
nq = LIST_NEXT(q, p_sibling);
/*
* Traced processes are killed since their existence
* means someone is screwing up. Since we reset the
* trace flags, the logic in sys_wait4() would not be
* triggered to reparent the process to its
* original parent, so we must do this here.
*/
if (q->p_flag & P_TRACED) {
if (q->p_opptr != q->p_pptr) {
struct proc *t = q->p_opptr;
proc_reparent(q, t ? t : initproc);
q->p_opptr = NULL;
} else
proc_reparent(q, initproc);
q->p_flag &= ~(P_TRACED|P_WAITED|P_FSTRACE);
psignal(q, SIGKILL);
} else {
proc_reparent(q, initproc);
}
}
/*
* Move proc from allproc to zombproc, it's now ready
* to be collected by parent. Remaining lwp resources
* will be freed in lwp_exit2() once we've switch to idle
* context.
* Changing the state to SZOMB stops it being found by pfind().
*/
LIST_REMOVE(p, p_list);
LIST_INSERT_HEAD(&zombproc, p, p_list);
p->p_stat = SZOMB;
LIST_REMOVE(l, l_list);
LIST_REMOVE(l, l_sibling);
l->l_flag |= L_DETACHED|L_PROCEXIT; /* detached from proc too */
l->l_stat = LSDEAD;
p->p_nrlwps--;
p->p_nlwps--;
/* Put in front of parent's sibling list for parent to collect it */
q = p->p_pptr;
q->p_nstopchild++;
if (LIST_FIRST(&q->p_children) != p) {
/* Put child where it can be found quickly */
LIST_REMOVE(p, p_sibling);
LIST_INSERT_HEAD(&q->p_children, p, p_sibling);
}
/*
* Notify parent that we're gone. If parent has the P_NOCLDWAIT
* flag set, notify init instead (and hope it will handle
* this situation).
*/
if (q->p_flag & P_NOCLDWAIT) {
proc_reparent(p, initproc);
/*
* If this was the last child of our parent, notify
* parent, so in case he was wait(2)ing, he will
* continue.
*/
if (LIST_FIRST(&q->p_children) == NULL)
wakeup(q);
}
/*
* Clear curlwp after we've done all operations
* that could block, and before tearing down the rest
* of the process state that might be used from clock, etc.
* Also, can't clear curlwp while we're still runnable,
* as we're not on a run queue (we are current, just not
* a proper proc any longer!).
*
* Other substructures are freed from wait().
*/
curlwp = NULL;
/* Delay release until after dropping the proclist lock */
plim = p->p_limit;
pstats = p->p_stats;
ps = p->p_sigacts;
p->p_limit = NULL;
p->p_stats = NULL;
p->p_sigacts = NULL;
/* Reload parent pointer, since p may have been reparented above */
q = p->p_pptr;
if ((p->p_flag & P_FSTRACE) == 0 && p->p_exitsig != 0) {
exit_psignal(p, q, &ksi);
do_psignal = 1;
}
/*
* Once we release the proclist lock, we shouldn't touch the
* process structure anymore, since it's now on the zombie
* list and available for collection by the parent.
*/
proclist_unlock_write(s);
if (do_psignal)
kpsignal(q, &ksi, NULL);
/* Wake up the parent so it can get exit status. */
wakeup(q);
/* Release substructures */
sigactsfree(ps);
limfree(plim);
pstatsfree(pstats);
#ifdef DEBUG
/* Nothing should use the process link anymore */
l->l_proc = NULL;
#endif
/* This process no longer needs to hold the kernel lock. */
KERNEL_PROC_UNLOCK(l);
/*
* Finally, call machine-dependent code to switch to a new
* context (possibly the idle context). Once we are no longer
* using the dead lwp's stack, lwp_exit2() will be called
* to arrange for the resources to be released.
*
* Note that cpu_exit() will end with a call equivalent to
* cpu_switch(), finishing our execution (pun intended).
*/
uvmexp.swtch++;
cpu_exit(l);
}
void
exit_lwps(struct lwp *l)
{
struct proc *p;
struct lwp *l2;
struct sadata_vp *vp;
int s, error;
lwpid_t waited;
p = l->l_proc;
/* XXX SMP
* This would be the right place to IPI any LWPs running on
* other processors so that they can notice the userret exit hook.
*/
p->p_userret = lwp_exit_hook;
p->p_userret_arg = NULL;
if (p->p_sa) {
SLIST_FOREACH(vp, &p->p_sa->sa_vps, savp_next) {
/*
* Make SA-cached LWPs normal process runnable
* LWPs so that they'll also self-destruct.
*/
DPRINTF(("exit_lwps: Making cached LWPs of %d on VP %d runnable: ",
p->p_pid, vp->savp_id));
SCHED_LOCK(s);
while ((l2 = sa_getcachelwp(vp)) != 0) {
l2->l_priority = l2->l_usrpri;
setrunnable(l2);
DPRINTF(("%d ", l2->l_lid));
}
SCHED_UNLOCK(s);
DPRINTF(("\n"));
/*
* Clear wokenq, the LWPs on the queue will
* run below.
*/
vp->savp_wokenq_head = NULL;
}
}
/*
* Interrupt LWPs in interruptable sleep, unsuspend suspended
* LWPs, make detached LWPs undetached (so we can wait for
* them) and then wait for everyone else to finish.
*/
LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
l2->l_flag &= ~(L_DETACHED|L_SA);
if ((l2->l_stat == LSSLEEP && (l2->l_flag & L_SINTR)) ||
l2->l_stat == LSSUSPENDED || l2->l_stat == LSSTOP) {
SCHED_LOCK(s);
setrunnable(l2);
SCHED_UNLOCK(s);
DPRINTF(("exit_lwps: Made %d.%d runnable\n",
p->p_pid, l2->l_lid));
}
}
while (p->p_nlwps > 1) {
DPRINTF(("exit_lwps: waiting for %d LWPs (%d runnable, %d zombies)\n",
p->p_nlwps, p->p_nrlwps, p->p_nzlwps));
error = lwp_wait1(l, 0, &waited, LWPWAIT_EXITCONTROL);
if (error)
panic("exit_lwps: lwp_wait1 failed with error %d\n",
error);
DPRINTF(("exit_lwps: Got LWP %d from lwp_wait1()\n", waited));
}
p->p_userret = NULL;
}
/* Wrapper function for use in p_userret */
static void
lwp_exit_hook(struct lwp *l, void *arg)
{
KERNEL_PROC_LOCK(l);
lwp_exit(l);
}
int
sys_wait4(struct lwp *l, void *v, register_t *retval)
{
struct sys_wait4_args /* {
syscallarg(int) pid;
syscallarg(int *) status;
syscallarg(int) options;
syscallarg(struct rusage *) rusage;
} */ *uap = v;
struct proc *child, *parent;
int status, error;
parent = l->l_proc;
if (SCARG(uap, pid) == 0)
SCARG(uap, pid) = -parent->p_pgid;
if (SCARG(uap, options) & ~(WUNTRACED|WNOHANG|WALTSIG|WALLSIG))
return (EINVAL);
error = find_stopped_child(parent, SCARG(uap,pid), SCARG(uap,options),
&child);
if (error != 0)
return error;
if (child == NULL) {
*retval = 0;
return 0;
}
/*
* Collect child u-areas.
*/
uvm_uarea_drain(FALSE);
retval[0] = child->p_pid;
if (P_ZOMBIE(child)) {
if (SCARG(uap, status)) {
status = child->p_xstat; /* convert to int */
error = copyout(&status, SCARG(uap, status),
sizeof(status));
if (error)
return (error);
}
if (SCARG(uap, rusage)) {
error = copyout(child->p_ru, SCARG(uap, rusage),
sizeof(struct rusage));
if (error)
return (error);
}
proc_free(child);
return 0;
}
/* child state must be SSTOP */
if (SCARG(uap, status)) {
status = W_STOPCODE(child->p_xstat);
return copyout(&status, SCARG(uap, status), sizeof(status));
}
return 0;
}
/*
* Scan list of child processes for a child process that has stopped or
* exited. Used by sys_wait4 and 'compat' equivalents.
*/
int
find_stopped_child(struct proc *parent, pid_t pid, int options,
struct proc **child_p)
{
struct proc *child;
int error;
for (;;) {
proclist_lock_read();
error = ECHILD;
LIST_FOREACH(child, &parent->p_children, p_sibling) {
if (pid >= 0) {
if (child->p_pid != pid) {
child = p_find(pid, PFIND_ZOMBIE |
PFIND_LOCKED);
if (child == NULL
|| child->p_pptr != parent) {
child = NULL;
break;
}
}
} else
if (pid != WAIT_ANY && child->p_pgid != -pid)
/* child not in correct pgrp */
continue;
/*
* Wait for processes with p_exitsig != SIGCHLD
* processes only if WALTSIG is set; wait for
* processes with p_exitsig == SIGCHLD only
* if WALTSIG is clear.
*/
if (((options & WALLSIG) == 0) &&
(options & WALTSIG ? child->p_exitsig == SIGCHLD
: P_EXITSIG(child) != SIGCHLD)){
if (child->p_pid == pid) {
child = NULL;
break;
}
continue;
}
error = 0;
if (child->p_stat == SZOMB && !(options & WNOZOMBIE))
break;
if (child->p_stat == SSTOP &&
(child->p_flag & P_WAITED) == 0 &&
(child->p_flag & P_TRACED || options & WUNTRACED)) {
if ((options & WNOWAIT) == 0) {
child->p_flag |= P_WAITED;
parent->p_nstopchild--;
}
break;
}
if (parent->p_nstopchild == 0 || child->p_pid == pid) {
child = NULL;
break;
}
}
proclist_unlock_read();
if (child != NULL || error != 0 || options & WNOHANG) {
*child_p = child;
return error;
}
error = tsleep(parent, PWAIT | PCATCH, "wait", 0);
if (error != 0)
return error;
}
}
/*
* Free a process after parent has taken all the state info.
*/
void
proc_free(struct proc *p)
{
struct proc *parent = p->p_pptr;
ksiginfo_t ksi;
int s;
KASSERT(p->p_nlwps == 0);
KASSERT(p->p_nzlwps == 0);
KASSERT(p->p_nrlwps == 0);
KASSERT(LIST_EMPTY(&p->p_lwps));
/*
* If we got the child via ptrace(2) or procfs, and
* the parent is different (meaning the process was
* attached, rather than run as a child), then we need
* to give it back to the old parent, and send the
* parent the exit signal. The rest of the cleanup
* will be done when the old parent waits on the child.
*/
if ((p->p_flag & P_TRACED) && p->p_opptr != parent){
parent = p->p_opptr;
if (parent == NULL)
parent = initproc;
proc_reparent(p, parent);
p->p_opptr = NULL;
p->p_flag &= ~(P_TRACED|P_WAITED|P_FSTRACE);
if (p->p_exitsig != 0) {
exit_psignal(p, parent, &ksi);
kpsignal(parent, &ksi, NULL);
}
wakeup(parent);
return;
}
scheduler_wait_hook(parent, p);
p->p_xstat = 0;
ruadd(&parent->p_stats->p_cru, p->p_ru);
/*
* At this point we are going to start freeing the final resources.
* If anyone tries to access the proc structure after here they
* will get a shock - bits are missing.
* Attempt to make it hard!
*/
p->p_stat = SIDL; /* not even a zombie any more */
pool_put(&rusage_pool, p->p_ru);
/*
* Finally finished with old proc entry.
* Unlink it from its process group and free it.
*/
leavepgrp(p);
s = proclist_lock_write();
LIST_REMOVE(p, p_list); /* off zombproc */
p->p_pptr->p_nstopchild--;
LIST_REMOVE(p, p_sibling);
proclist_unlock_write(s);
/*
* Decrement the count of procs running with this uid.
*/
(void)chgproccnt(p->p_cred->p_ruid, -1);
/*
* Free up credentials.
*/
if (--p->p_cred->p_refcnt == 0) {
crfree(p->p_cred->pc_ucred);
pool_put(&pcred_pool, p->p_cred);
}
/*
* Release reference to text vnode
*/
if (p->p_textvp)
vrele(p->p_textvp);
/* Release any SA state. */
if (p->p_sa)
sa_release(p);
/* Free proc structure and let pid be reallocated */
proc_free_mem(p);
}
/*
* make process 'parent' the new parent of process 'child'.
*
* Must be called with proclist_lock_write() held.
*/
void
proc_reparent(struct proc *child, struct proc *parent)
{
if (child->p_pptr == parent)
return;
if (child->p_stat == SZOMB
|| (child->p_stat == SSTOP && !(child->p_flag & P_WAITED))) {
child->p_pptr->p_nstopchild--;
parent->p_nstopchild++;
}
if (parent == initproc)
child->p_exitsig = SIGCHLD;
LIST_REMOVE(child, p_sibling);
LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
child->p_pptr = parent;
}