diff options
Diffstat (limited to 'sys/kern/kern_exit.c')
| -rw-r--r-- | sys/kern/kern_exit.c | 790 |
1 files changed, 790 insertions, 0 deletions
diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c new file mode 100644 index 0000000..c65dfeb --- /dev/null +++ b/sys/kern/kern_exit.c @@ -0,0 +1,790 @@ +/* + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. 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 8.7 (Berkeley) 2/12/94 + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "opt_compat.h" +#include "opt_ktrace.h" +#include "opt_mac.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/sysproto.h> +#include <sys/eventhandler.h> +#include <sys/kernel.h> +#include <sys/malloc.h> +#include <sys/lock.h> +#include <sys/mutex.h> +#include <sys/proc.h> +#include <sys/pioctl.h> +#include <sys/tty.h> +#include <sys/wait.h> +#include <sys/vmmeter.h> +#include <sys/vnode.h> +#include <sys/resourcevar.h> +#include <sys/signalvar.h> +#include <sys/sched.h> +#include <sys/sx.h> +#include <sys/ptrace.h> +#include <sys/acct.h> /* for acct_process() function prototype */ +#include <sys/filedesc.h> +#include <sys/mac.h> +#include <sys/shm.h> +#include <sys/sem.h> +#include <sys/jail.h> +#ifdef KTRACE +#include <sys/ktrace.h> +#endif + +#include <vm/vm.h> +#include <vm/vm_extern.h> +#include <vm/vm_param.h> +#include <vm/pmap.h> +#include <vm/vm_map.h> +#include <vm/vm_page.h> +#include <vm/uma.h> +#include <sys/user.h> + +/* Required to be non-static for SysVR4 emulator */ +MALLOC_DEFINE(M_ZOMBIE, "zombie", "zombie proc status"); + +static int wait1(struct thread *, struct wait_args *, int); + +/* + * exit -- + * Death of process. + * + * MPSAFE + */ +void +sys_exit(struct thread *td, struct sys_exit_args *uap) +{ + + mtx_lock(&Giant); + exit1(td, W_EXITCODE(uap->rval, 0)); + /* NOTREACHED */ +} + +/* + * 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 thread *td, int rv) +{ + struct proc *p, *nq, *q; + struct tty *tp; + struct vnode *ttyvp; + struct vmspace *vm; + struct vnode *vtmp; +#ifdef KTRACE + struct vnode *tracevp; + struct ucred *tracecred; +#endif + + GIANT_REQUIRED; + + p = td->td_proc; + if (p == initproc) { + printf("init died (signal %d, exit %d)\n", + WTERMSIG(rv), WEXITSTATUS(rv)); + panic("Going nowhere without my init!"); + } + + /* + * MUST abort all other threads before proceeding past here. + */ + PROC_LOCK(p); + if (p->p_flag & P_SA || p->p_numthreads > 1) { + /* + * First check if some other thread got here before us.. + * if so, act apropriatly, (exit or suspend); + */ + thread_suspend_check(0); + + /* + * Kill off the other threads. This requires + * Some co-operation from other parts of the kernel + * so it may not be instant. + * With this state set: + * Any thread entering the kernel from userspace will + * thread_exit() in trap(). Any thread attempting to + * sleep will return immediatly + * with EINTR or EWOULDBLOCK, which will hopefully force them + * to back out to userland, freeing resources as they go, and + * anything attempting to return to userland will thread_exit() + * from userret(). thread_exit() will unsuspend us + * when the last other thread exits. + */ + if (thread_single(SINGLE_EXIT)) { + panic ("Exit: Single threading fouled up"); + } + /* + * All other activity in this process is now stopped. + * Remove excess KSEs and KSEGRPS. XXXKSE (when we have them) + * ... + * Turn off threading support. + */ + p->p_flag &= ~P_SA; + thread_single_end(); /* Don't need this any more. */ + } + /* + * With this state set: + * Any thread entering the kernel from userspace will thread_exit() + * in trap(). Any thread attempting to sleep will return immediatly + * with EINTR or EWOULDBLOCK, which will hopefully force them + * to back out to userland, freeing resources as they go, and + * anything attempting to return to userland will thread_exit() + * from userret(). thread_exit() will do a wakeup on p->p_numthreads + * if it transitions to 1. + */ + + p->p_flag |= P_WEXIT; + PROC_UNLOCK(p); + + /* Are we a task leader? */ + if (p == p->p_leader) { + mtx_lock(&ppeers_lock); + q = p->p_peers; + while (q != NULL) { + PROC_LOCK(q); + psignal(q, SIGKILL); + PROC_UNLOCK(q); + q = q->p_peers; + } + while (p->p_peers != NULL) + msleep(p, &ppeers_lock, PWAIT, "exit1", 0); + mtx_unlock(&ppeers_lock); + } + +#ifdef PGINPROF + vmsizmon(); +#endif + STOPEVENT(p, S_EXIT, rv); + wakeup(&p->p_stype); /* Wakeup anyone in procfs' PIOCWAIT */ + + /* + * Check if any loadable modules need anything done at process exit. + * e.g. SYSV IPC stuff + * XXX what if one of these generates an error? + */ + EVENTHANDLER_INVOKE(process_exit, p); + + MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage), + M_ZOMBIE, M_WAITOK); + /* + * If parent is waiting for us to exit or exec, + * P_PPWAIT is set; we will wakeup the parent below. + */ + PROC_LOCK(p); + stopprofclock(p); + p->p_flag &= ~(P_TRACED | P_PPWAIT); + SIGEMPTYSET(p->p_siglist); + SIGEMPTYSET(td->td_siglist); + + /* + * Stop the real interval timer. If the handler is currently + * executing, prevent it from rearming itself and let it finish. + */ + if (timevalisset(&p->p_realtimer.it_value) && + callout_stop(&p->p_itcallout) == 0) { + timevalclear(&p->p_realtimer.it_interval); + msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0); + KASSERT(!timevalisset(&p->p_realtimer.it_value), + ("realtime timer is still armed")); + } + PROC_UNLOCK(p); + + /* + * Reset any sigio structures pointing to us as a result of + * F_SETOWN with our pid. + */ + funsetownlst(&p->p_sigiolst); + + /* + * Close open files and release open-file table. + * This may block! + */ + fdfree(td); + + /* + * Remove ourself from our leader's peer list and wake our leader. + */ + mtx_lock(&ppeers_lock); + if (p->p_leader->p_peers) { + q = p->p_leader; + while (q->p_peers != p) + q = q->p_peers; + q->p_peers = p->p_peers; + wakeup(p->p_leader); + } + mtx_unlock(&ppeers_lock); + + /* The next two chunks should probably be moved to vmspace_exit. */ + vm = p->p_vmspace; + /* + * Release user portion of address space. + * This releases references to vnodes, + * which could cause I/O if the file has been unlinked. + * Need to do this early enough that we can still sleep. + * Can't free the entire vmspace as the kernel stack + * may be mapped within that space also. + * + * Processes sharing the same vmspace may exit in one order, and + * get cleaned up by vmspace_exit() in a different order. The + * last exiting process to reach this point releases as much of + * the environment as it can, and the last process cleaned up + * by vmspace_exit() (which decrements exitingcnt) cleans up the + * remainder. + */ + ++vm->vm_exitingcnt; + if (--vm->vm_refcnt == 0) { + shmexit(vm); + vm_page_lock_queues(); + pmap_remove_pages(vmspace_pmap(vm), vm_map_min(&vm->vm_map), + vm_map_max(&vm->vm_map)); + vm_page_unlock_queues(); + (void) vm_map_remove(&vm->vm_map, vm_map_min(&vm->vm_map), + vm_map_max(&vm->vm_map)); + } + + sx_xlock(&proctree_lock); + if (SESS_LEADER(p)) { + struct session *sp; + + sp = p->p_session; + if (sp->s_ttyvp) { + /* + * Controlling process. + * Signal foreground pgrp, + * drain controlling terminal + * and revoke access to controlling terminal. + */ + if (sp->s_ttyp && (sp->s_ttyp->t_session == sp)) { + tp = sp->s_ttyp; + if (sp->s_ttyp->t_pgrp) { + PGRP_LOCK(sp->s_ttyp->t_pgrp); + pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); + PGRP_UNLOCK(sp->s_ttyp->t_pgrp); + } + /* XXX tp should be locked. */ + sx_xunlock(&proctree_lock); + (void) ttywait(tp); + sx_xlock(&proctree_lock); + /* + * The tty could have been revoked + * if we blocked. + */ + if (sp->s_ttyvp) { + ttyvp = sp->s_ttyvp; + SESS_LOCK(p->p_session); + sp->s_ttyvp = NULL; + SESS_UNLOCK(p->p_session); + sx_xunlock(&proctree_lock); + VOP_REVOKE(ttyvp, REVOKEALL); + vrele(ttyvp); + sx_xlock(&proctree_lock); + } + } + if (sp->s_ttyvp) { + ttyvp = sp->s_ttyvp; + SESS_LOCK(p->p_session); + sp->s_ttyvp = NULL; + SESS_UNLOCK(p->p_session); + vrele(ttyvp); + } + /* + * s_ttyp is not zero'd; we use this to indicate + * that the session once had a controlling terminal. + * (for logging and informational purposes) + */ + } + SESS_LOCK(p->p_session); + sp->s_leader = NULL; + SESS_UNLOCK(p->p_session); + } + fixjobc(p, p->p_pgrp, 0); + sx_xunlock(&proctree_lock); + (void)acct_process(td); +#ifdef KTRACE + /* + * release trace file + */ + PROC_LOCK(p); + mtx_lock(&ktrace_mtx); + p->p_traceflag = 0; /* don't trace the vrele() */ + tracevp = p->p_tracevp; + p->p_tracevp = NULL; + tracecred = p->p_tracecred; + p->p_tracecred = NULL; + mtx_unlock(&ktrace_mtx); + PROC_UNLOCK(p); + if (tracevp != NULL) + vrele(tracevp); + if (tracecred != NULL) + crfree(tracecred); +#endif + /* + * Release reference to text vnode + */ + if ((vtmp = p->p_textvp) != NULL) { + p->p_textvp = NULL; + vrele(vtmp); + } + + /* + * Release our limits structure. + */ + mtx_assert(&Giant, MA_OWNED); + if (--p->p_limit->p_refcnt == 0) { + FREE(p->p_limit, M_SUBPROC); + p->p_limit = NULL; + } + + /* + * Release this thread's reference to the ucred. The actual proc + * reference will stay around until the proc is harvested by + * wait(). At this point the ucred is immutable (no other threads + * from this proc are around that can change it) so we leave the + * per-thread ucred pointer intact in case it is needed although + * in theory nothing should be using it at this point. + */ + crfree(td->td_ucred); + + /* + * Remove proc from allproc queue and pidhash chain. + * Place onto zombproc. Unlink from parent's child list. + */ + sx_xlock(&allproc_lock); + LIST_REMOVE(p, p_list); + LIST_INSERT_HEAD(&zombproc, p, p_list); + LIST_REMOVE(p, p_hash); + sx_xunlock(&allproc_lock); + + sx_xlock(&proctree_lock); + q = LIST_FIRST(&p->p_children); + if (q != NULL) /* only need this if any child is S_ZOMB */ + wakeup(initproc); + for (; q != NULL; q = nq) { + nq = LIST_NEXT(q, p_sibling); + PROC_LOCK(q); + proc_reparent(q, initproc); + q->p_sigparent = SIGCHLD; + /* + * Traced processes are killed + * since their existence means someone is screwing up. + */ + if (q->p_flag & P_TRACED) { + q->p_flag &= ~P_TRACED; + psignal(q, SIGKILL); + } + PROC_UNLOCK(q); + } + + /* + * Save exit status and final rusage info, adding in child rusage + * info and self times. + */ + PROC_LOCK(p); + p->p_xstat = rv; + *p->p_ru = p->p_stats->p_ru; + mtx_lock_spin(&sched_lock); + calcru(p, &p->p_ru->ru_utime, &p->p_ru->ru_stime, NULL); + mtx_unlock_spin(&sched_lock); + ruadd(p->p_ru, &p->p_stats->p_cru); + + /* + * Notify interested parties of our demise. + */ + KNOTE(&p->p_klist, NOTE_EXIT); + + /* + * Notify parent that we're gone. If parent has the PS_NOCLDWAIT + * flag set, or if the handler is set to SIG_IGN, notify process + * 1 instead (and hope it will handle this situation). + */ + PROC_LOCK(p->p_pptr); + mtx_lock(&p->p_pptr->p_sigacts->ps_mtx); + if (p->p_pptr->p_sigacts->ps_flag & (PS_NOCLDWAIT | PS_CLDSIGIGN)) { + struct proc *pp; + + mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); + pp = p->p_pptr; + PROC_UNLOCK(pp); + proc_reparent(p, initproc); + PROC_LOCK(p->p_pptr); + /* + * If this was the last child of our parent, notify + * parent, so in case he was wait(2)ing, he will + * continue. + */ + if (LIST_EMPTY(&pp->p_children)) + wakeup(pp); + } else + mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); + + if (p->p_sigparent && p->p_pptr != initproc) + psignal(p->p_pptr, p->p_sigparent); + else + psignal(p->p_pptr, SIGCHLD); + PROC_UNLOCK(p->p_pptr); + + /* + * If this is a kthread, then wakeup anyone waiting for it to exit. + */ + if (p->p_flag & P_KTHREAD) + wakeup(p); + PROC_UNLOCK(p); + + /* + * Finally, call machine-dependent code to release the remaining + * resources including address space. + * The address space is released by "vmspace_exitfree(p)" in + * vm_waitproc(). + */ + cpu_exit(td); + + 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 acquiring 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 */ + /* + * Allow the scheduler to adjust the priority of the + * parent when a kseg is exiting. + */ + if (p->p_pid != 1) + sched_exit(p->p_pptr, p); + + /* + * Make sure the scheduler takes this thread out of its tables etc. + * This will also release this thread's reference to the ucred. + * Other thread parts to release include pcb bits and such. + */ + thread_exit(); +} + +#ifdef COMPAT_43 +/* + * MPSAFE. The dirty work is handled by wait1(). + */ +int +owait(struct thread *td, struct owait_args *uap __unused) +{ + 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(struct thread *td, struct wait_args *uap) +{ + + return (wait1(td, uap, 0)); +} + +/* + * MPSAFE + */ +static int +wait1(struct thread *td, struct wait_args *uap, int compat) +{ + struct rusage ru; + int nfound; + struct proc *p, *q, *t; + int status, error; + + 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) { + 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. + */ + sx_xlock(&allproc_lock); + LIST_REMOVE(p, p_list); /* off zombproc */ + sx_xunlock(&allproc_lock); + LIST_REMOVE(p, p_sibling); + leavepgrp(p); + 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 credentials, arguments, and sigacts + */ + crfree(p->p_ucred); + p->p_ucred = NULL; + pargs_drop(p->p_args); + p->p_args = NULL; + sigacts_free(p->p_sigacts); + p->p_sigacts = NULL; + + /* + * do any thread-system specific cleanups + */ + thread_wait(p); + + /* + * 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); +#ifdef MAC + mac_destroy_proc(p); +#endif + 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); + } + mtx_lock_spin(&sched_lock); + if (P_SHOULDSTOP(p) && (p->p_suspcount == p->p_numthreads) && + ((p->p_flag & P_WAITED) == 0) && + (p->p_flag & P_TRACED || uap->options & WUNTRACED)) { + mtx_unlock_spin(&sched_lock); + 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); + } + mtx_unlock_spin(&sched_lock); + 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(struct proc *child, 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; +} |
