48bfcddd94
in specific situations. The owner thread must be blocked, and the borrower can not proceed back to user space with the borrowed KSE. The borrower will return the KSE on the next context switch where teh owner wants it back. This removes a lot of possible race conditions and deadlocks. It is consceivable that the borrower should inherit the priority of the owner too. that's another discussion and would be simple to do. Also, as part of this, the "preallocatd spare thread" is attached to the thread doing a syscall rather than the KSE. This removes the need to lock the scheduler when we want to access it, as it's now "at hand". DDB now shows a lot mor info for threaded proceses though it may need some optimisation to squeeze it all back into 80 chars again. (possible JKH project) Upcalls are now "bound" threads, but "KSE Lending" now means that other completing syscalls can be completed using that KSE before the upcall finally makes it back to the UTS. (getting threads OUT OF THE KERNEL is one of the highest priorities in the KSE system.) The upcall when it happens will present all the completed syscalls to the KSE for selection.
891 lines
22 KiB
C
891 lines
22 KiB
C
/*
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* Copyright (c) 1982, 1986, 1989, 1991, 1993
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* The Regents of the University of California. All rights reserved.
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* (c) UNIX System Laboratories, Inc.
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* All or some portions of this file are derived from material licensed
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* to the University of California by American Telephone and Telegraph
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* Co. or Unix System Laboratories, Inc. and are reproduced herein with
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* the permission of UNIX System Laboratories, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)kern_exit.c 8.7 (Berkeley) 2/12/94
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* $FreeBSD$
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*/
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#include "opt_compat.h"
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#include "opt_ktrace.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/sysproto.h>
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#include <sys/kernel.h>
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#include <sys/malloc.h>
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#include <sys/lock.h>
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#include <sys/mutex.h>
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#include <sys/proc.h>
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#include <sys/pioctl.h>
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#include <sys/tty.h>
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#include <sys/wait.h>
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#include <sys/vmmeter.h>
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#include <sys/vnode.h>
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#include <sys/resourcevar.h>
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#include <sys/signalvar.h>
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#include <sys/sx.h>
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#include <sys/ptrace.h>
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#include <sys/acct.h> /* for acct_process() function prototype */
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#include <sys/filedesc.h>
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#include <sys/shm.h>
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#include <sys/sem.h>
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#include <sys/jail.h>
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#ifdef KTRACE
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#include <sys/ktrace.h>
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#endif
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#include <vm/vm.h>
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#include <vm/vm_extern.h>
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#include <vm/vm_param.h>
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#include <vm/pmap.h>
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#include <vm/vm_map.h>
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#include <vm/uma.h>
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#include <sys/user.h>
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/* Required to be non-static for SysVR4 emulator */
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MALLOC_DEFINE(M_ZOMBIE, "zombie", "zombie proc status");
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static MALLOC_DEFINE(M_ATEXIT, "atexit", "atexit callback");
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static int wait1(struct thread *, struct wait_args *, int);
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/*
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* callout list for things to do at exit time
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*/
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struct exitlist {
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exitlist_fn function;
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TAILQ_ENTRY(exitlist) next;
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};
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TAILQ_HEAD(exit_list_head, exitlist);
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static struct exit_list_head exit_list = TAILQ_HEAD_INITIALIZER(exit_list);
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/*
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* exit --
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* Death of process.
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*
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* MPSAFE
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*/
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void
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sys_exit(td, uap)
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struct thread *td;
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struct sys_exit_args /* {
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int rval;
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} */ *uap;
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{
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mtx_lock(&Giant);
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exit1(td, W_EXITCODE(uap->rval, 0));
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/* NOTREACHED */
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}
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/*
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* Exit: deallocate address space and other resources, change proc state
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* to zombie, and unlink proc from allproc and parent's lists. Save exit
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* status and rusage for wait(). Check for child processes and orphan them.
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*/
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void
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exit1(td, rv)
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register struct thread *td;
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int rv;
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{
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struct exitlist *ep;
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struct proc *p, *nq, *q;
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struct tty *tp;
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struct vnode *ttyvp;
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register struct vmspace *vm;
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struct vnode *vtmp;
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#ifdef KTRACE
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struct vnode *tracevp;
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#endif
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GIANT_REQUIRED;
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p = td->td_proc;
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if (p == initproc) {
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printf("init died (signal %d, exit %d)\n",
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WTERMSIG(rv), WEXITSTATUS(rv));
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panic("Going nowhere without my init!");
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}
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/*
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* XXXXKSE: MUST abort all other threads before proceeding past here.
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*/
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PROC_LOCK(p);
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if (p->p_flag & P_KSES) {
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/*
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* First check if some other thread got here before us..
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* if so, act apropriatly, (exit or suspend);
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*/
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thread_suspend_check(0);
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/*
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* Here is a trick..
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* We need to free up our KSE to process other threads
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* so that we can safely set the UNBOUND flag
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* (whether or not we have a mailbox) as we are NEVER
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* going to return to the user.
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* The flag will not be set yet if we are exiting
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* because of a signal, pagefault, or similar
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* (or even an exit(2) from the UTS).
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*/
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td->td_flags |= TDF_UNBOUND;
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/*
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* Kill off the other threads. This requires
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* Some co-operation from other parts of the kernel
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* so it may not be instant.
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* With this state set:
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* Any thread entering the kernel from userspace will
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* thread_exit() in trap(). Any thread attempting to
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* sleep will return immediatly
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* with EINTR or EWOULDBLOCK, which will hopefully force them
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* to back out to userland, freeing resources as they go, and
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* anything attempting to return to userland will thread_exit()
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* from userret(). thread_exit() will unsuspend us
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* when the last other thread exits.
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*/
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if (thread_single(SINGLE_EXIT)) {
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panic ("Exit: Single threading fouled up");
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}
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/*
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* All other activity in this process is now stopped.
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* Remove excess KSEs and KSEGRPS. XXXKSE (when we have them)
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* ...
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* Turn off threading support.
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*/
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p->p_flag &= ~P_KSES;
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td->td_flags &= ~TDF_UNBOUND;
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thread_single_end(); /* Don't need this any more. */
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}
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/*
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* With this state set:
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* Any thread entering the kernel from userspace will thread_exit()
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* in trap(). Any thread attempting to sleep will return immediatly
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* with EINTR or EWOULDBLOCK, which will hopefully force them
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* to back out to userland, freeing resources as they go, and
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* anything attempting to return to userland will thread_exit()
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* from userret(). thread_exit() will do a wakeup on p->p_numthreads
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* if it transitions to 1.
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*/
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p->p_flag |= P_WEXIT;
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PROC_UNLOCK(p);
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/* Are we a task leader? */
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PROC_LOCK(p);
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if (p == p->p_leader) {
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q = p->p_peers;
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while (q != NULL) {
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PROC_LOCK(q);
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psignal(q, SIGKILL);
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PROC_UNLOCK(q);
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q = q->p_peers;
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}
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while (p->p_peers)
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msleep(p, &p->p_mtx, PWAIT, "exit1", 0);
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}
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PROC_UNLOCK(p);
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#ifdef PGINPROF
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vmsizmon();
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#endif
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STOPEVENT(p, S_EXIT, rv);
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wakeup(&p->p_stype); /* Wakeup anyone in procfs' PIOCWAIT */
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/*
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* Check if any loadable modules need anything done at process exit.
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* e.g. SYSV IPC stuff
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* XXX what if one of these generates an error?
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*/
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TAILQ_FOREACH(ep, &exit_list, next)
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(*ep->function)(p);
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stopprofclock(p);
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MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage),
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M_ZOMBIE, M_WAITOK);
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/*
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* If parent is waiting for us to exit or exec,
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* P_PPWAIT is set; we will wakeup the parent below.
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*/
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PROC_LOCK(p);
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p->p_flag &= ~(P_TRACED | P_PPWAIT);
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SIGEMPTYSET(p->p_siglist);
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PROC_UNLOCK(p);
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if (timevalisset(&p->p_realtimer.it_value))
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callout_stop(&p->p_itcallout);
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/*
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* Reset any sigio structures pointing to us as a result of
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* F_SETOWN with our pid.
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*/
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funsetownlst(&p->p_sigiolst);
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/*
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* Close open files and release open-file table.
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* This may block!
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*/
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fdfree(td); /* XXXKSE *//* may not be the one in proc */
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/*
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* Remove ourself from our leader's peer list and wake our leader.
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*/
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PROC_LOCK(p->p_leader);
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if (p->p_leader->p_peers) {
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q = p->p_leader;
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while (q->p_peers != p)
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q = q->p_peers;
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q->p_peers = p->p_peers;
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wakeup(p->p_leader);
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}
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PROC_UNLOCK(p->p_leader);
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/* The next two chunks should probably be moved to vmspace_exit. */
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vm = p->p_vmspace;
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/*
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* Release user portion of address space.
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* This releases references to vnodes,
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* which could cause I/O if the file has been unlinked.
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* Need to do this early enough that we can still sleep.
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* Can't free the entire vmspace as the kernel stack
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* may be mapped within that space also.
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*/
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if (--vm->vm_refcnt == 0) {
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if (vm->vm_shm)
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shmexit(p);
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pmap_remove_pages(vmspace_pmap(vm), vm_map_min(&vm->vm_map),
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vm_map_max(&vm->vm_map));
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(void) vm_map_remove(&vm->vm_map, vm_map_min(&vm->vm_map),
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vm_map_max(&vm->vm_map));
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vm->vm_freer = p;
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}
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sx_xlock(&proctree_lock);
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if (SESS_LEADER(p)) {
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register struct session *sp;
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sp = p->p_session;
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if (sp->s_ttyvp) {
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/*
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* Controlling process.
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* Signal foreground pgrp,
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* drain controlling terminal
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* and revoke access to controlling terminal.
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*/
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if (sp->s_ttyp && (sp->s_ttyp->t_session == sp)) {
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tp = sp->s_ttyp;
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if (sp->s_ttyp->t_pgrp) {
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PGRP_LOCK(sp->s_ttyp->t_pgrp);
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pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1);
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PGRP_UNLOCK(sp->s_ttyp->t_pgrp);
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}
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/* XXX tp should be locked. */
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sx_xunlock(&proctree_lock);
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(void) ttywait(tp);
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sx_xlock(&proctree_lock);
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/*
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* The tty could have been revoked
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* if we blocked.
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*/
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if (sp->s_ttyvp) {
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ttyvp = sp->s_ttyvp;
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SESS_LOCK(p->p_session);
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sp->s_ttyvp = NULL;
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SESS_UNLOCK(p->p_session);
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sx_xunlock(&proctree_lock);
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VOP_REVOKE(ttyvp, REVOKEALL);
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vrele(ttyvp);
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sx_xlock(&proctree_lock);
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}
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}
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if (sp->s_ttyvp) {
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ttyvp = sp->s_ttyvp;
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SESS_LOCK(p->p_session);
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sp->s_ttyvp = NULL;
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SESS_UNLOCK(p->p_session);
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vrele(ttyvp);
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}
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/*
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* s_ttyp is not zero'd; we use this to indicate
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* that the session once had a controlling terminal.
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* (for logging and informational purposes)
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*/
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}
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SESS_LOCK(p->p_session);
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sp->s_leader = NULL;
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SESS_UNLOCK(p->p_session);
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}
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fixjobc(p, p->p_pgrp, 0);
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sx_xunlock(&proctree_lock);
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(void)acct_process(td);
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#ifdef KTRACE
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/*
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* release trace file
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*/
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PROC_LOCK(p);
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mtx_lock(&ktrace_mtx);
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p->p_traceflag = 0; /* don't trace the vrele() */
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tracevp = p->p_tracep;
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p->p_tracep = NULL;
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mtx_unlock(&ktrace_mtx);
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PROC_UNLOCK(p);
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if (tracevp != NULL)
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vrele(tracevp);
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#endif
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/*
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* Release reference to text vnode
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*/
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if ((vtmp = p->p_textvp) != NULL) {
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p->p_textvp = NULL;
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vrele(vtmp);
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}
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/*
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* Release our limits structure.
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*/
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mtx_assert(&Giant, MA_OWNED);
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if (--p->p_limit->p_refcnt == 0) {
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FREE(p->p_limit, M_SUBPROC);
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p->p_limit = NULL;
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}
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/*
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* Release this thread's reference to the ucred. The actual proc
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* reference will stay around until the proc is harvested by
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* wait(). At this point the ucred is immutable (no other threads
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* from this proc are around that can change it) so we leave the
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* per-thread ucred pointer intact in case it is needed although
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* in theory nothing should be using it at this point.
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*/
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crfree(td->td_ucred);
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/*
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* Remove proc from allproc queue and pidhash chain.
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* Place onto zombproc. Unlink from parent's child list.
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*/
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sx_xlock(&allproc_lock);
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LIST_REMOVE(p, p_list);
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LIST_INSERT_HEAD(&zombproc, p, p_list);
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LIST_REMOVE(p, p_hash);
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sx_xunlock(&allproc_lock);
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sx_xlock(&proctree_lock);
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q = LIST_FIRST(&p->p_children);
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if (q != NULL) /* only need this if any child is S_ZOMB */
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wakeup(initproc);
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for (; q != NULL; q = nq) {
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nq = LIST_NEXT(q, p_sibling);
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PROC_LOCK(q);
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proc_reparent(q, initproc);
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q->p_sigparent = SIGCHLD;
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/*
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* Traced processes are killed
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* since their existence means someone is screwing up.
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*/
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if (q->p_flag & P_TRACED) {
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q->p_flag &= ~P_TRACED;
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psignal(q, SIGKILL);
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}
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PROC_UNLOCK(q);
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}
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/*
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* Save exit status and final rusage info, adding in child rusage
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* info and self times.
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*/
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PROC_LOCK(p);
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p->p_xstat = rv;
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*p->p_ru = p->p_stats->p_ru;
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mtx_lock_spin(&sched_lock);
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calcru(p, &p->p_ru->ru_utime, &p->p_ru->ru_stime, NULL);
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mtx_unlock_spin(&sched_lock);
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ruadd(p->p_ru, &p->p_stats->p_cru);
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/*
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* Notify interested parties of our demise.
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*/
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KNOTE(&p->p_klist, NOTE_EXIT);
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|
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/*
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* Notify parent that we're gone. If parent has the PS_NOCLDWAIT
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* flag set, or if the handler is set to SIG_IGN, notify process
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* 1 instead (and hope it will handle this situation).
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*/
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PROC_LOCK(p->p_pptr);
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if (p->p_pptr->p_procsig->ps_flag & (PS_NOCLDWAIT | PS_CLDSIGIGN)) {
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struct proc *pp;
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pp = p->p_pptr;
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PROC_UNLOCK(pp);
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proc_reparent(p, initproc);
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|
PROC_LOCK(p->p_pptr);
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|
/*
|
|
* If this was the last child of our parent, notify
|
|
* parent, so in case he was wait(2)ing, he will
|
|
* continue.
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*/
|
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if (LIST_EMPTY(&pp->p_children))
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wakeup(pp);
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}
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|
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if (p->p_sigparent && p->p_pptr != initproc)
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psignal(p->p_pptr, p->p_sigparent);
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else
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psignal(p->p_pptr, SIGCHLD);
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PROC_UNLOCK(p->p_pptr);
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/*
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* If this is a kthread, then wakeup anyone waiting for it to exit.
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*/
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|
if (p->p_flag & P_KTHREAD)
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wakeup(p);
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PROC_UNLOCK(p);
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|
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/*
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|
* Finally, call machine-dependent code to release the remaining
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* resources including address space, the kernel stack and pcb.
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|
* The address space is released by "vmspace_exitfree(p)" in
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* vm_waitproc().
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|
*/
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cpu_exit(td);
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PROC_LOCK(p);
|
|
PROC_LOCK(p->p_pptr);
|
|
sx_xunlock(&proctree_lock);
|
|
mtx_lock_spin(&sched_lock);
|
|
while (mtx_owned(&Giant))
|
|
mtx_unlock(&Giant);
|
|
|
|
/*
|
|
* We have to wait until after releasing all locks before
|
|
* changing p_state. If we block on a mutex then we will be
|
|
* back at SRUN when we resume and our parent will never
|
|
* harvest us.
|
|
*/
|
|
p->p_state = PRS_ZOMBIE;
|
|
|
|
wakeup(p->p_pptr);
|
|
PROC_UNLOCK(p->p_pptr);
|
|
cnt.v_swtch++;
|
|
binuptime(PCPU_PTR(switchtime));
|
|
PCPU_SET(switchticks, ticks);
|
|
|
|
cpu_sched_exit(td); /* XXXKSE check if this should be in thread_exit */
|
|
/*
|
|
* Make sure this thread is discarded from the zombie.
|
|
* This will also release this thread's reference to the ucred.
|
|
*/
|
|
thread_exit();
|
|
panic("exit1");
|
|
}
|
|
|
|
#ifdef COMPAT_43
|
|
/*
|
|
* MPSAFE. The dirty work is handled by wait1().
|
|
*/
|
|
int
|
|
owait(td, uap)
|
|
struct thread *td;
|
|
register struct owait_args /* {
|
|
int dummy;
|
|
} */ *uap;
|
|
{
|
|
struct wait_args w;
|
|
|
|
w.options = 0;
|
|
w.rusage = NULL;
|
|
w.pid = WAIT_ANY;
|
|
w.status = NULL;
|
|
return (wait1(td, &w, 1));
|
|
}
|
|
#endif /* COMPAT_43 */
|
|
|
|
/*
|
|
* MPSAFE. The dirty work is handled by wait1().
|
|
*/
|
|
int
|
|
wait4(td, uap)
|
|
struct thread *td;
|
|
struct wait_args *uap;
|
|
{
|
|
|
|
return (wait1(td, uap, 0));
|
|
}
|
|
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
static int
|
|
wait1(td, uap, compat)
|
|
register struct thread *td;
|
|
register struct wait_args /* {
|
|
int pid;
|
|
int *status;
|
|
int options;
|
|
struct rusage *rusage;
|
|
} */ *uap;
|
|
int compat;
|
|
{
|
|
struct rusage ru;
|
|
int nfound;
|
|
struct proc *p, *q, *t;
|
|
int status, error;
|
|
struct thread *td2;
|
|
struct kse *ke;
|
|
struct ksegrp *kg;
|
|
|
|
q = td->td_proc;
|
|
if (uap->pid == 0) {
|
|
PROC_LOCK(q);
|
|
uap->pid = -q->p_pgid;
|
|
PROC_UNLOCK(q);
|
|
}
|
|
if (uap->options &~ (WUNTRACED|WNOHANG|WCONTINUED|WLINUXCLONE))
|
|
return (EINVAL);
|
|
mtx_lock(&Giant);
|
|
loop:
|
|
nfound = 0;
|
|
sx_xlock(&proctree_lock);
|
|
LIST_FOREACH(p, &q->p_children, p_sibling) {
|
|
PROC_LOCK(p);
|
|
if (uap->pid != WAIT_ANY &&
|
|
p->p_pid != uap->pid && p->p_pgid != -uap->pid) {
|
|
PROC_UNLOCK(p);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* This special case handles a kthread spawned by linux_clone
|
|
* (see linux_misc.c). The linux_wait4 and linux_waitpid
|
|
* functions need to be able to distinguish between waiting
|
|
* on a process and waiting on a thread. It is a thread if
|
|
* p_sigparent is not SIGCHLD, and the WLINUXCLONE option
|
|
* signifies we want to wait for threads and not processes.
|
|
*/
|
|
if ((p->p_sigparent != SIGCHLD) ^
|
|
((uap->options & WLINUXCLONE) != 0)) {
|
|
PROC_UNLOCK(p);
|
|
continue;
|
|
}
|
|
|
|
nfound++;
|
|
if (p->p_state == PRS_ZOMBIE) {
|
|
/*
|
|
* charge childs scheduling cpu usage to parent
|
|
* XXXKSE assume only one thread & kse & ksegrp
|
|
* keep estcpu in each ksegrp
|
|
* so charge it to the ksegrp that did the wait
|
|
* since process estcpu is sum of all ksegrps,
|
|
* this is strictly as expected.
|
|
* Assume that the child process aggregated all
|
|
* tke estcpu into the 'build-in' ksegrp.
|
|
* XXXKSE
|
|
*/
|
|
if (curthread->td_proc->p_pid != 1) {
|
|
mtx_lock_spin(&sched_lock);
|
|
curthread->td_ksegrp->kg_estcpu =
|
|
ESTCPULIM(curthread->td_ksegrp->kg_estcpu +
|
|
FIRST_KSEGRP_IN_PROC(p)->kg_estcpu);
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
|
|
td->td_retval[0] = p->p_pid;
|
|
#ifdef COMPAT_43
|
|
if (compat)
|
|
td->td_retval[1] = p->p_xstat;
|
|
else
|
|
#endif
|
|
if (uap->status) {
|
|
status = p->p_xstat; /* convert to int */
|
|
PROC_UNLOCK(p);
|
|
if ((error = copyout(&status,
|
|
uap->status, sizeof(status)))) {
|
|
sx_xunlock(&proctree_lock);
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
PROC_LOCK(p);
|
|
}
|
|
if (uap->rusage) {
|
|
bcopy(p->p_ru, &ru, sizeof(ru));
|
|
PROC_UNLOCK(p);
|
|
if ((error = copyout(&ru,
|
|
uap->rusage, sizeof (struct rusage)))) {
|
|
sx_xunlock(&proctree_lock);
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
} else
|
|
PROC_UNLOCK(p);
|
|
/*
|
|
* If we got the child via a ptrace 'attach',
|
|
* we need to give it back to the old parent.
|
|
*/
|
|
if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) {
|
|
PROC_LOCK(p);
|
|
p->p_oppid = 0;
|
|
proc_reparent(p, t);
|
|
PROC_UNLOCK(p);
|
|
psignal(t, SIGCHLD);
|
|
wakeup(t);
|
|
PROC_UNLOCK(t);
|
|
sx_xunlock(&proctree_lock);
|
|
mtx_unlock(&Giant);
|
|
return (0);
|
|
}
|
|
/*
|
|
* Remove other references to this process to ensure
|
|
* we have an exclusive reference.
|
|
*/
|
|
leavepgrp(p);
|
|
|
|
sx_xlock(&allproc_lock);
|
|
LIST_REMOVE(p, p_list); /* off zombproc */
|
|
sx_xunlock(&allproc_lock);
|
|
|
|
LIST_REMOVE(p, p_sibling);
|
|
sx_xunlock(&proctree_lock);
|
|
|
|
/*
|
|
* As a side effect of this lock, we know that
|
|
* all other writes to this proc are visible now, so
|
|
* no more locking is needed for p.
|
|
*/
|
|
PROC_LOCK(p);
|
|
p->p_xstat = 0; /* XXX: why? */
|
|
PROC_UNLOCK(p);
|
|
PROC_LOCK(q);
|
|
ruadd(&q->p_stats->p_cru, p->p_ru);
|
|
PROC_UNLOCK(q);
|
|
FREE(p->p_ru, M_ZOMBIE);
|
|
p->p_ru = NULL;
|
|
|
|
/*
|
|
* Decrement the count of procs running with this uid.
|
|
*/
|
|
(void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0);
|
|
|
|
/*
|
|
* Free up credentials.
|
|
*/
|
|
crfree(p->p_ucred);
|
|
p->p_ucred = NULL; /* XXX: why? */
|
|
|
|
/*
|
|
* Remove unused arguments
|
|
*/
|
|
pargs_drop(p->p_args);
|
|
p->p_args = NULL;
|
|
|
|
if (--p->p_procsig->ps_refcnt == 0) {
|
|
if (p->p_sigacts != &p->p_uarea->u_sigacts)
|
|
FREE(p->p_sigacts, M_SUBPROC);
|
|
FREE(p->p_procsig, M_SUBPROC);
|
|
p->p_procsig = NULL;
|
|
}
|
|
|
|
/*
|
|
* There should only be one
|
|
* but do it right anyhow.
|
|
*/
|
|
FOREACH_KSEGRP_IN_PROC(p, kg) {
|
|
FOREACH_KSE_IN_GROUP(kg, ke) {
|
|
/* Free the KSE spare thread. */
|
|
if (ke->ke_tdspare != NULL) {
|
|
thread_free(ke->ke_tdspare);
|
|
ke->ke_tdspare = NULL;
|
|
}
|
|
}
|
|
}
|
|
FOREACH_THREAD_IN_PROC(p, td2) {
|
|
if (td2->td_standin != NULL) {
|
|
thread_free(td2->td_standin);
|
|
td2->td_standin = NULL;
|
|
}
|
|
}
|
|
thread_reap(); /* check for zombie threads */
|
|
|
|
/*
|
|
* Give vm and machine-dependent layer a chance
|
|
* to free anything that cpu_exit couldn't
|
|
* release while still running in process context.
|
|
*/
|
|
vm_waitproc(p);
|
|
mtx_destroy(&p->p_mtx);
|
|
KASSERT(FIRST_THREAD_IN_PROC(p),
|
|
("wait1: no residual thread!"));
|
|
uma_zfree(proc_zone, p);
|
|
sx_xlock(&allproc_lock);
|
|
nprocs--;
|
|
sx_xunlock(&allproc_lock);
|
|
mtx_unlock(&Giant);
|
|
return (0);
|
|
}
|
|
if (P_SHOULDSTOP(p) && ((p->p_flag & P_WAITED) == 0) &&
|
|
(p->p_flag & P_TRACED || uap->options & WUNTRACED)) {
|
|
p->p_flag |= P_WAITED;
|
|
sx_xunlock(&proctree_lock);
|
|
td->td_retval[0] = p->p_pid;
|
|
#ifdef COMPAT_43
|
|
if (compat) {
|
|
td->td_retval[1] = W_STOPCODE(p->p_xstat);
|
|
PROC_UNLOCK(p);
|
|
error = 0;
|
|
} else
|
|
#endif
|
|
if (uap->status) {
|
|
status = W_STOPCODE(p->p_xstat);
|
|
PROC_UNLOCK(p);
|
|
error = copyout(&status,
|
|
uap->status, sizeof(status));
|
|
} else {
|
|
PROC_UNLOCK(p);
|
|
error = 0;
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
if (uap->options & WCONTINUED && (p->p_flag & P_CONTINUED)) {
|
|
sx_xunlock(&proctree_lock);
|
|
td->td_retval[0] = p->p_pid;
|
|
p->p_flag &= ~P_CONTINUED;
|
|
PROC_UNLOCK(p);
|
|
|
|
if (uap->status) {
|
|
status = SIGCONT;
|
|
error = copyout(&status,
|
|
uap->status, sizeof(status));
|
|
} else
|
|
error = 0;
|
|
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
PROC_UNLOCK(p);
|
|
}
|
|
if (nfound == 0) {
|
|
sx_xunlock(&proctree_lock);
|
|
mtx_unlock(&Giant);
|
|
return (ECHILD);
|
|
}
|
|
if (uap->options & WNOHANG) {
|
|
sx_xunlock(&proctree_lock);
|
|
td->td_retval[0] = 0;
|
|
mtx_unlock(&Giant);
|
|
return (0);
|
|
}
|
|
PROC_LOCK(q);
|
|
sx_xunlock(&proctree_lock);
|
|
error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0);
|
|
PROC_UNLOCK(q);
|
|
if (error) {
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
goto loop;
|
|
}
|
|
|
|
/*
|
|
* Make process 'parent' the new parent of process 'child'.
|
|
* Must be called with an exclusive hold of proctree lock.
|
|
*/
|
|
void
|
|
proc_reparent(child, parent)
|
|
register struct proc *child;
|
|
register struct proc *parent;
|
|
{
|
|
|
|
sx_assert(&proctree_lock, SX_XLOCKED);
|
|
PROC_LOCK_ASSERT(child, MA_OWNED);
|
|
if (child->p_pptr == parent)
|
|
return;
|
|
|
|
LIST_REMOVE(child, p_sibling);
|
|
LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
|
|
child->p_pptr = parent;
|
|
}
|
|
|
|
/*
|
|
* The next two functions are to handle adding/deleting items on the
|
|
* exit callout list
|
|
*
|
|
* at_exit():
|
|
* Take the arguments given and put them onto the exit callout list,
|
|
* However first make sure that it's not already there.
|
|
* returns 0 on success.
|
|
*/
|
|
|
|
int
|
|
at_exit(function)
|
|
exitlist_fn function;
|
|
{
|
|
struct exitlist *ep;
|
|
|
|
#ifdef INVARIANTS
|
|
/* Be noisy if the programmer has lost track of things */
|
|
if (rm_at_exit(function))
|
|
printf("WARNING: exit callout entry (%p) already present\n",
|
|
function);
|
|
#endif
|
|
ep = malloc(sizeof(*ep), M_ATEXIT, M_NOWAIT);
|
|
if (ep == NULL)
|
|
return (ENOMEM);
|
|
ep->function = function;
|
|
TAILQ_INSERT_TAIL(&exit_list, ep, next);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Scan the exit callout list for the given item and remove it.
|
|
* Returns the number of items removed (0 or 1)
|
|
*/
|
|
int
|
|
rm_at_exit(function)
|
|
exitlist_fn function;
|
|
{
|
|
struct exitlist *ep;
|
|
|
|
TAILQ_FOREACH(ep, &exit_list, next) {
|
|
if (ep->function == function) {
|
|
TAILQ_REMOVE(&exit_list, ep, next);
|
|
free(ep, M_ATEXIT);
|
|
return (1);
|
|
}
|
|
}
|
|
return (0);
|
|
}
|