 @@ -1,1033 +1,1033 @@
-/*	$NetBSD: kern_exit.c,v 1.214.4.2.2.1 2015/11/07 20:42:59 snj Exp $	*/
+/*	$NetBSD: kern_exit.c,v 1.214.4.2.2.2 2015/11/07 20:49:19 snj Exp $	*/
 /*-
  * Copyright (c) 1998, 1999, 2006, 2007, 2008 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, and by Andrew Doran.
+ *
  * 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.
+ *
  * 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 1.214.4.2.2.1 2015/11/07 20:42:59 snj Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_exit.c,v 1.214.4.2.2.2 2015/11/07 20:49:19 snj Exp $");
 #include "opt_ktrace.h"
 #include "opt_perfctrs.h"
 #include "opt_sa.h"
 #include "opt_sysv.h"
 #include <sys/param.h>
 #include <sys/aio.h>
 #include <sys/systm.h>
 #include <sys/ioctl.h>
 #include <sys/tty.h>
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <sys/kernel.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/uidinfo.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/kauth.h>
 #include <sys/sleepq.h>
 #include <sys/lockdebug.h>
 #include <sys/ktrace.h>
 #include <sys/cpu.h>
 #include <sys/lwpctl.h>
 #include <sys/atomic.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 int find_stopped_child(struct proc *, pid_t, int, struct proc **, int *);
 static void proc_free(struct proc *, struct rusage *);
 /*
  * Fill in the appropriate signal information, and signal the parent.
  */
 static void
 exit_psignal(struct proc *p, struct proc *pp, ksiginfo_t *ksi)
+{
 	KSI_INIT(ksi);
 	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.
 	 * It's safe to access p->p_cred unlocked here.
 	 */
 	ksi->ksi_pid = p->p_pid;
 	ksi->ksi_uid = kauth_cred_geteuid(p->p_cred);
 	ksi->ksi_status = p->p_xstat;
 	/* XXX: is this still valid? */
 	ksi->ksi_utime = p->p_stats->p_ru.ru_utime.tv_sec;
 	ksi->ksi_stime = p->p_stats->p_ru.ru_stime.tv_sec;
+}
 /*
  * exit --
  *	Death of process.
  */
 int
 sys_exit(struct lwp *l, const struct sys_exit_args *uap, register_t *retval)
+{
 	/* {
 		syscallarg(int)	rval;
 	} */
 	struct proc *p = l->l_proc;
 	/* Don't call exit1() multiple times in the same process. */
 	mutex_enter(p->p_lock);
 	if (p->p_sflag & PS_WEXIT) {
 		mutex_exit(p->p_lock);
 		lwp_exit(l);
+	}
 	/* exit1() will release the mutex. */
 	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.
+ *
  * Must be called with p->p_lock held.  Does not return.
  */
 void
 exit1(struct lwp *l, int rv)
+{
 	struct proc	*p, *q, *nq;
 	struct pgrp	*pgrp;
 	ksiginfo_t	ksi;
 	ksiginfoq_t	kq;
 	int		wakeinit, sa;
 	p = l->l_proc;
 	KASSERT(mutex_owned(p->p_lock));
 	if (__predict_false(p == initproc))
 		panic("init died (signal %d, exit %d)",
 		    WTERMSIG(rv), WEXITSTATUS(rv));
 	/*
 	 * Disable scheduler activation upcalls.  We're trying to get out of
 	 * here.
 	 */
 	sa = 0;
 #ifdef KERN_SA
 	if ((p->p_sa != NULL)) {
 		l->l_pflag |= LP_SA_NOBLOCK;
 		sa = 1;
+	}
 #endif
 	p->p_sflag |= PS_WEXIT;
 	/*
 	 * Force all other LWPs to exit before we do.  Only then can we
 	 * begin to tear down the rest of the process state.
 	 */
 	if (sa || p->p_nlwps > 1)
 		exit_lwps(l);
 	ksiginfo_queue_init(&kq);
 	/*
 	 * If we have been asked to stop on exit, do so now.
 	 */
 	if (__predict_false(p->p_sflag & PS_STOPEXIT)) {
 		KERNEL_UNLOCK_ALL(l, &l->l_biglocks);
 		sigclearall(p, &contsigmask, &kq);
 		if (!mutex_tryenter(proc_lock)) {
 			mutex_exit(p->p_lock);
 			mutex_enter(proc_lock);
 			mutex_enter(p->p_lock);
+		}
 		p->p_waited = 0;
 		p->p_pptr->p_nstopchild++;
 		mutex_exit(proc_lock);
 		p->p_stat = SSTOP;
 		mutex_exit(proc_lock);
 		lwp_lock(l);
 		p->p_nrlwps--;
 		l->l_stat = LSSTOP;
 		mutex_exit(p->p_lock);
 		mi_switch(l);
 		KERNEL_LOCK(l->l_biglocks, l);
 		mutex_enter(p->p_lock);
+	}
 	/*
 	 * Bin any remaining signals and mark the process as dying so it will
 	 * not be found for, e.g. signals.
 	 */
 	sigfillset(&p->p_sigctx.ps_sigignore);
 	sigclearall(p, NULL, &kq);
 	p->p_stat = SDYING;
 	mutex_exit(p->p_lock);
 	ksiginfo_queue_drain(&kq);
 	/* Destroy any lwpctl info. */
 	if (p->p_lwpctl != NULL)
 		lwp_ctl_exit();
 	/* Destroy all AIO works */
 	aio_exit(p, p->p_aio);
 	/*
 	 * Drain all remaining references that procfs, ptrace and others may
 	 * have on the process.
 	 */
 	rw_enter(&p->p_reflock, RW_WRITER);
 	DPRINTF(("exit1: %d.%d exiting.\n", p->p_pid, l->l_lid));
 	timers_free(p, TIMERS_ALL);
 #if defined(__HAVE_RAS)
 	ras_purgeall();
 #endif
 	/*
 	 * Close open files, release open-file table and free signal
 	 * actions.  This may block!
 	 */
 	fd_free();
 	cwdfree(p->p_cwdi);
 	p->p_cwdi = NULL;
 	doexithooks(p);
 	sigactsfree(p->p_sigacts);
 	/*
 	 * Write out accounting data.
 	 */
 	(void)acct_process(l);
 #ifdef KTRACE
 	/*
 	 * Release trace file.
 	 */
 	if (p->p_tracep != NULL) {
 		mutex_enter(&ktrace_lock);
 		ktrderef(p);
 		mutex_exit(&ktrace_lock);
+	}
 #endif
 	/*
 	 * If emulation has process exit hook, call it now.
 	 * Set the exit status now so that the exit hook has
 	 * an opportunity to tweak it (COMPAT_LINUX requires
 	 * this for thread group emulation)
 	 */
 	p->p_xstat = rv;
 	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);
 	/*
 	 * Stop profiling.
 	 */
 	if (__predict_false((p->p_stflag & PST_PROFIL) != 0)) {
 		mutex_spin_enter(&p->p_stmutex);
 		stopprofclock(p);
 		mutex_spin_exit(&p->p_stmutex);
+	}
 	/*
 	 * If parent is waiting for us to exit or exec, PL_PPWAIT is set; we
 	 * wake up the parent early to avoid deadlock.  We can do this once
 	 * the VM resources are released.
 	 */
 	mutex_enter(proc_lock);
 	if (p->p_lflag & PL_PPWAIT) {
 		p->p_lflag &= ~PL_PPWAIT;
 		cv_broadcast(&p->p_pptr->p_waitcv);
+	}
 	if (SESS_LEADER(p)) {
 		struct vnode *vprele = NULL, *vprevoke = NULL;
 		struct session *sp = p->p_session;
 		struct tty *tp;
 		if (sp->s_ttyvp) {
 			/*
 			 * Controlling process.
 			 * Signal foreground pgrp,
 			 * drain controlling terminal
 			 * and revoke access to controlling terminal.
 			 */
 			tp = sp->s_ttyp;
 			mutex_spin_enter(&tty_lock);
 			if (tp->t_session == sp) {
 				/* we can't guarantee the revoke will do this */
 				pgrp = tp->t_pgrp;
 				tp->t_pgrp = NULL;
 				tp->t_session = NULL;
 				mutex_spin_exit(&tty_lock);
 				if (pgrp != NULL) {
 					pgsignal(pgrp, SIGHUP, 1);
+				}
 				mutex_exit(proc_lock);
 				(void) ttywait(tp);
 				mutex_enter(proc_lock);
 				/* The tty could have been revoked. */
 				vprevoke = sp->s_ttyvp;
 			} else
 				mutex_spin_exit(&tty_lock);
 			vprele = 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;
 		if (vprevoke != NULL || vprele != NULL) {
 			if (vprevoke != NULL) {
 				SESSRELE(sp);
 				mutex_exit(proc_lock);
 				VOP_REVOKE(vprevoke, REVOKEALL);
 			} else
 				mutex_exit(proc_lock);
 			if (vprele != NULL)
 				vrele(vprele);
 			mutex_enter(proc_lock);
+		}
+	}
 	fixjobc(p, p->p_pgrp, 0);
 	/*
 	 * Finalize the last LWP's specificdata, as well as the
 	 * specificdata for the proc itself.
 	 */
 	lwp_finispecific(l);
 	proc_finispecific(p);
 	/*
 	 * 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
 	/*
 	 * 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 (__predict_false(p->p_slflag & PSL_CHTRACED)) {
 		PROCLIST_FOREACH(q, &allproc) {
 			if ((q->p_flag & PK_MARKER) != 0)
 				continue;
 			if (q->p_opptr == p)
 				q->p_opptr = NULL;
+		}
+	}
 	/*
 	 * Give orphaned children to init(8).
 	 */
 	q = LIST_FIRST(&p->p_children);
 	wakeinit = (q != NULL);
 	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 (__predict_false(q->p_slflag & PSL_TRACED)) {
 			mutex_enter(p->p_lock);
 			q->p_slflag &= ~(PSL_TRACED|PSL_FSTRACE|PSL_SYSCALL);
 			mutex_exit(p->p_lock);
 			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);
 			killproc(q, "orphaned traced process");
 		} else
 			proc_reparent(q, initproc);
+	}
 	/*
 	 * Move proc from allproc to zombproc, it's now nearly ready to be
 	 * collected by parent.
 	 */
 	LIST_REMOVE(l, l_list);
 	LIST_REMOVE(p, p_list);
 	LIST_INSERT_HEAD(&zombproc, p, p_list);
 	/*
 	 * Mark the process as dead.  We must do this before we signal
 	 * the parent.
 	 */
 	p->p_stat = SDEAD;
 	/* 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 & (PK_NOCLDWAIT|PK_CLDSIGIGN)) {
 		proc_reparent(p, initproc);
 		wakeinit = 1;
 		/*
 		 * 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)
 			cv_broadcast(&q->p_waitcv);
+	}
 	/* Reload parent pointer, since p may have been reparented above */
 	q = p->p_pptr;
 	if (__predict_false((p->p_slflag & PSL_FSTRACE) == 0 && p->p_exitsig != 0)) {
 		exit_psignal(p, q, &ksi);
 		kpsignal(q, &ksi, NULL);
+	}
 	/* Calculate the final rusage info.  */
 	calcru(p, &p->p_stats->p_ru.ru_utime, &p->p_stats->p_ru.ru_stime,
 	    NULL, NULL);
 	if (wakeinit)
 		cv_broadcast(&initproc->p_waitcv);
 	callout_destroy(&l->l_timeout_ch);
 	/*
 	 * Remaining lwp resources will be freed in lwp_exit2() once we've
 	 * switch to idle context; at that point, we will be marked as a
 	 * full blown zombie.
 	 */
 	mutex_enter(p->p_lock);
 	lwp_drainrefs(l);
 	lwp_lock(l);
 	l->l_prflag &= ~LPR_DETACHED;
 	l->l_stat = LSZOMB;
 	lwp_unlock(l);
 	KASSERT(curlwp == l);
 	KASSERT(p->p_nrlwps == 1);
 	KASSERT(p->p_nlwps == 1);
 	p->p_stat = SZOMB;
 	p->p_nrlwps--;
 	p->p_nzlwps++;
 	p->p_ndlwps = 0;
 	mutex_exit(p->p_lock);
 	/*
 	 * Signal the parent to collect us, and drop the proclist lock.
 	 * Drop debugger/procfs lock; no new references can be gained.
 	 */
 	cv_broadcast(&p->p_pptr->p_waitcv);
 	rw_exit(&p->p_reflock);
 	mutex_exit(proc_lock);
 	/* Verify that we hold no locks other than the kernel lock. */
 	LOCKDEBUG_BARRIER(&kernel_lock, 0);
 	/*
 	 * NOTE: WE ARE NO LONGER ALLOWED TO SLEEP!
 	 */
 	/*
 	 * Give machine-dependent code a chance to free any MD LWP
 	 * resources.  This must be done before uvm_lwp_exit(), in
 	 * case these resources are in the PCB.
 	 */
 #ifndef __NO_CPU_LWP_FREE
 	cpu_lwp_free(l, 1);
 #endif
 	pmap_deactivate(l);
 	/* This process no longer needs to hold the kernel lock. */
 #ifdef notyet
 	/* XXXSMP hold in lwp_userret() */
 	KERNEL_UNLOCK_LAST(l);
 #else
 	KERNEL_UNLOCK_ALL(l, NULL);
 #endif
 	lwp_exit_switchaway(l);
+}
 void
 exit_lwps(struct lwp *l)
+{
 	struct proc *p;
 	struct lwp *l2;
 	int error;
 	lwpid_t waited;
 	int nlocks;
 	KERNEL_UNLOCK_ALL(l, &nlocks);
 	p = l->l_proc;
 	KASSERT(mutex_owned(p->p_lock));
 #ifdef KERN_SA
 	if (p->p_sa != NULL) {
 		struct sadata_vp *vp;
 		SLIST_FOREACH(vp, &p->p_sa->sa_vps, savp_next) {
 			/*
 			 * Make SA-cached LWPs normal process interruptable
 			 * so that the exit code can wake them. Locking
 			 * savp_mutex locks all the lwps on this vp that
 			 * we need to adjust.
 			 */
 			mutex_enter(&vp->savp_mutex);
 			DPRINTF(("exit_lwps: Making cached LWPs of %d on "
 			    "VP %d interruptable: ", p->p_pid, vp->savp_id));
 			TAILQ_FOREACH(l2, &vp->savp_lwpcache, l_sleepchain) {
 				l2->l_flag |= LW_SINTR;
 				DPRINTF(("%d ", l2->l_lid));
+			}
 			DPRINTF(("\n"));
 			DPRINTF(("exit_lwps: Making unblocking LWPs of %d on "
 			    "VP %d interruptable: ", p->p_pid, vp->savp_id));
 			TAILQ_FOREACH(l2, &vp->savp_woken, l_sleepchain) {
 				vp->savp_woken_count--;
 				l2->l_flag |= LW_SINTR;
 				DPRINTF(("%d ", l2->l_lid));
+			}
 			DPRINTF(("\n"));
 			mutex_exit(&vp->savp_mutex);
+		}
+	}
 #endif
  retry:
 	/*
 	 * Interrupt LWPs in interruptable sleep, unsuspend suspended
 	 * LWPs and then wait for everyone else to finish.
 	 */
 	LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
 		if (l2 == l)
 			continue;
 		lwp_lock(l2);
 		l2->l_flag &= ~LW_SA;
 		l2->l_flag |= LW_WEXIT;
 		if ((l2->l_stat == LSSLEEP && (l2->l_flag & LW_SINTR)) ||
 		    l2->l_stat == LSSUSPENDED || l2->l_stat == LSSTOP) {
 		    	/* setrunnable() will release the lock. */
 			setrunnable(l2);
 			DPRINTF(("exit_lwps: Made %d.%d runnable\n",
 			    p->p_pid, l2->l_lid));
 			continue;
+		}
 		lwp_unlock(l2);
+	}
 	while (p->p_nlwps > 1) {
 		DPRINTF(("exit_lwps: waiting for %d LWPs (%d zombies)\n",
 		    p->p_nlwps, p->p_nzlwps));
 		error = lwp_wait1(l, 0, &waited, LWPWAIT_EXITCONTROL);
 		if (p->p_nlwps == 1)
 			break;
 		if (error == EDEADLK) {
 			/*
 			 * LWPs can get suspended/slept behind us.
 			 * (eg. sa_setwoken)
 			 * kick them again and retry.
 			 */
 			goto retry;
+		}
 		if (error)
 			panic("exit_lwps: lwp_wait1 failed with error %d",
 			    error);
 		DPRINTF(("exit_lwps: Got LWP %d from lwp_wait1()\n", waited));
+	}
 	KERNEL_LOCK(nlocks, l);
 	KASSERT(p->p_nlwps == 1);
+}
 int
 do_sys_wait(struct lwp *l, int *pid, int *status, int options,
     struct rusage *ru, int *was_zombie)
+{
 	struct proc	*child;
 	int		error;
 	mutex_enter(proc_lock);
 	error = find_stopped_child(l->l_proc, *pid, options, &child, status);
 	if (child == NULL) {
 		mutex_exit(proc_lock);
 		*pid = 0;
 		return error;
+	}
 	*pid = child->p_pid;
 	if (child->p_stat == SZOMB) {
 		/* proc_free() will release the proc_lock. */
 		*was_zombie = 1;
 		if (options & WNOWAIT)
 			mutex_exit(proc_lock);
 		else {
 			proc_free(child, ru);
+		}
 	} else {
 		/* Child state must have been SSTOP. */
 		*was_zombie = 0;
 		mutex_exit(proc_lock);
 		*status = W_STOPCODE(*status);
+	}
 	return 0;
+}
 int
 sys_wait4(struct lwp *l, const struct sys_wait4_args *uap, register_t *retval)
+{
 	/* {
 		syscallarg(int)			pid;
 		syscallarg(int *)		status;
 		syscallarg(int)			options;
 		syscallarg(struct rusage *)	rusage;
 	} */
 	int		status, error;
 	int		was_zombie;
 	struct rusage	ru;
 	int pid = SCARG(uap, pid);
 	error = do_sys_wait(l, &pid, &status, SCARG(uap, options),
 	    SCARG(uap, rusage) != NULL ? &ru : NULL, &was_zombie);
 	retval[0] = pid;
 	if (pid == 0)
 		return error;
 	if (SCARG(uap, rusage))
 		error = copyout(&ru, SCARG(uap, rusage), sizeof(ru));
 	if (error == 0 && SCARG(uap, status))
 		error = copyout(&status, SCARG(uap, status), sizeof(status));
 	return error;
+}
 /*
  * Scan list of child processes for a child process that has stopped or
  * exited.  Used by sys_wait4 and 'compat' equivalents.
+ *
  * Must be called with the proc_lock held, and may release while waiting.
  */
 static int
 find_stopped_child(struct proc *parent, pid_t pid, int options,
 		   struct proc **child_p, int *status_p)
+{
 	struct proc *child, *dead;
 	int error;
 	KASSERT(mutex_owned(proc_lock));
 	if (options & ~(WUNTRACED|WNOHANG|WALTSIG|WALLSIG)
 	    && !(options & WOPTSCHECKED)) {
 		*child_p = NULL;
 		return EINVAL;
+	}
 	if (pid == 0 && !(options & WOPTSCHECKED))
 		pid = -parent->p_pgid;
 	for (;;) {
 		error = ECHILD;
 		dead = NULL;
 		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 ((options & WNOZOMBIE) == 0) {
 				if (child->p_stat == SZOMB)
 					break;
 				if (child->p_stat == SDEAD) {
 					/*
 					 * We may occasionally arrive here
 					 * after receiving a signal, but
 					 * immediatley before the child
 					 * process is zombified.  The wait
 					 * will be short, so avoid returning
 					 * to userspace.
 					 */
 					dead = child;
+				}
+			}
 			if (child->p_stat == SSTOP &&
 			    child->p_waited == 0 &&
 			    (child->p_slflag & PSL_TRACED ||
 			    options & WUNTRACED)) {
 				if ((options & WNOWAIT) == 0) {
 					child->p_waited = 1;
 					parent->p_nstopchild--;
+				}
 				break;
+			}
 			if (parent->p_nstopchild == 0 || child->p_pid == pid) {
 				child = NULL;
 				break;
+			}
+		}
 		if (child != NULL || error != 0 ||
 		    ((options & WNOHANG) != 0 && dead == NULL)) {
 		    	if (child != NULL) {
 			    	*status_p = child->p_xstat;
+			}
 			*child_p = child;
 			return error;
+		}
 		/*
 		 * Wait for another child process to stop.
 		 */
 		error = cv_wait_sig(&parent->p_waitcv, proc_lock);
 		if (error != 0) {
 			*child_p = NULL;
 			return error;
+		}
+	}
+}
 /*
  * Free a process after parent has taken all the state info.  Must be called
  * with the proclist lock held, and will release before returning.
+ *
  * *ru is returned to the caller, and must be freed by the caller.
  */
 static void
 proc_free(struct proc *p, struct rusage *ru)
+{
 	struct proc *parent;
 	struct lwp *l;
 	ksiginfo_t ksi;
 	kauth_cred_t cred1, cred2;
 	uid_t uid;
 	KASSERT(mutex_owned(proc_lock));
 	KASSERT(p->p_nlwps == 1);
 	KASSERT(p->p_nzlwps == 1);
 	KASSERT(p->p_nrlwps == 0);
 	KASSERT(p->p_stat == SZOMB);
 	/*
 	 * 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_slflag & PSL_TRACED) != 0) {
 		parent = p->p_pptr;
 		if (p->p_opptr != parent){
 			mutex_enter(p->p_lock);
 			p->p_slflag &= ~(PSL_TRACED|PSL_FSTRACE|PSL_SYSCALL);
 			mutex_exit(p->p_lock);
 			parent = p->p_opptr;
 			if (parent == NULL)
 				parent = initproc;
 			proc_reparent(p, parent);
 			p->p_opptr = NULL;
 			if (p->p_exitsig != 0) {
 				exit_psignal(p, parent, &ksi);
 				kpsignal(parent, &ksi, NULL);
+			}
 			cv_broadcast(&parent->p_waitcv);
 			mutex_exit(proc_lock);
 			return;
+		}
+	}
 	/*
 	 * Finally finished with old proc entry.  Unlink it from its process
 	 * group.
 	 */
 	leavepgrp(p);
 	parent = p->p_pptr;
 	sched_proc_exit(parent, p);
 	/*
 	 * Add child times of exiting process onto its own times.
 	 * This cannot be done any earlier else it might get done twice.
 	 */
 	l = LIST_FIRST(&p->p_lwps);
 	p->p_stats->p_ru.ru_nvcsw += (l->l_ncsw - l->l_nivcsw);
 	p->p_stats->p_ru.ru_nivcsw += l->l_nivcsw;
 	ruadd(&p->p_stats->p_ru, &l->l_ru);
 	ruadd(&p->p_stats->p_ru, &p->p_stats->p_cru);
 	ruadd(&parent->p_stats->p_cru, &p->p_stats->p_ru);
 	if (ru != NULL)
 		*ru = p->p_stats->p_ru;
 	p->p_xstat = 0;
 	/* Release any SA state. */
 #ifdef KERN_SA
 	if (p->p_sa)
 		sa_release(p);
 #endif
 	/*
 	 * 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!  We
 	 * don't bother with any further locking past this point.
 	 */
 	p->p_stat = SIDL;		/* not even a zombie any more */
 	LIST_REMOVE(p, p_list);	/* off zombproc */
 	parent = p->p_pptr;
 	p->p_pptr->p_nstopchild--;
 	LIST_REMOVE(p, p_sibling);
 	/*
 	 * Let pid be reallocated.
 	 */
 	proc_free_pid(p);
 	mutex_exit(proc_lock);
 	/*
 	 * Delay release until after lwp_free.
 	 */
 	cred2 = l->l_cred;
 	/*
 	 * Free the last LWP's resources.
+	 *
 	 * lwp_free ensures the LWP is no longer running on another CPU.
 	 */
 	lwp_free(l, false, true);
 	/*
 	 * Now no one except us can reach the process p.
 	 */
 	/*
 	 * Decrement the count of procs running with this uid.
 	 */
 	cred1 = p->p_cred;
 	uid = kauth_cred_getuid(cred1);
 	(void)chgproccnt(uid, -1);
 	/*
 	 * Release substructures.
 	 */
 	limfree(p->p_limit);
 	pstatsfree(p->p_stats);
 	kauth_cred_free(cred1);
 	kauth_cred_free(cred2);
 	/*
 	 * Release reference to text vnode
 	 */
 	if (p->p_textvp)
 		vrele(p->p_textvp);
 	mutex_destroy(&p->p_auxlock);
 	mutex_obj_free(p->p_lock);
 	mutex_destroy(&p->p_stmutex);
 	cv_destroy(&p->p_waitcv);
 	cv_destroy(&p->p_lwpcv);
 	rw_destroy(&p->p_reflock);
 	proc_free_mem(p);
+}
 /*
  * make process 'parent' the new parent of process 'child'.
+ *
  * Must be called with proc_lock held.
  */
 void
 proc_reparent(struct proc *child, struct proc *parent)
+{
 	KASSERT(mutex_owned(proc_lock));
 	if (child->p_pptr == parent)
 		return;
 	if (child->p_stat == SZOMB || child->p_stat == SDEAD ||
 	    (child->p_stat == SSTOP && !child->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;
 	child->p_ppid = parent->p_pid;
+}