]>
git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - kernel/exit.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
8 #include <linux/slab.h>
9 #include <linux/interrupt.h>
10 #include <linux/module.h>
11 #include <linux/capability.h>
12 #include <linux/completion.h>
13 #include <linux/personality.h>
14 #include <linux/tty.h>
15 #include <linux/mnt_namespace.h>
16 #include <linux/iocontext.h>
17 #include <linux/key.h>
18 #include <linux/security.h>
19 #include <linux/cpu.h>
20 #include <linux/acct.h>
21 #include <linux/tsacct_kern.h>
22 #include <linux/file.h>
23 #include <linux/fdtable.h>
24 #include <linux/binfmts.h>
25 #include <linux/nsproxy.h>
26 #include <linux/pid_namespace.h>
27 #include <linux/ptrace.h>
28 #include <linux/profile.h>
29 #include <linux/mount.h>
30 #include <linux/proc_fs.h>
31 #include <linux/kthread.h>
32 #include <linux/mempolicy.h>
33 #include <linux/taskstats_kern.h>
34 #include <linux/delayacct.h>
35 #include <linux/freezer.h>
36 #include <linux/cgroup.h>
37 #include <linux/syscalls.h>
38 #include <linux/signal.h>
39 #include <linux/posix-timers.h>
40 #include <linux/cn_proc.h>
41 #include <linux/mutex.h>
42 #include <linux/futex.h>
43 #include <linux/pipe_fs_i.h>
44 #include <linux/audit.h> /* for audit_free() */
45 #include <linux/resource.h>
46 #include <linux/blkdev.h>
47 #include <linux/task_io_accounting_ops.h>
48 #include <linux/tracehook.h>
49 #include <linux/init_task.h>
50 #include <trace/sched.h>
52 #include <asm/uaccess.h>
53 #include <asm/unistd.h>
54 #include <asm/pgtable.h>
55 #include <asm/mmu_context.h>
56 #include "cred-internals.h"
58 DEFINE_TRACE(sched_process_free
);
59 DEFINE_TRACE(sched_process_exit
);
60 DEFINE_TRACE(sched_process_wait
);
62 static void exit_mm(struct task_struct
* tsk
);
64 static void __unhash_process(struct task_struct
*p
)
67 detach_pid(p
, PIDTYPE_PID
);
68 if (thread_group_leader(p
)) {
69 detach_pid(p
, PIDTYPE_PGID
);
70 detach_pid(p
, PIDTYPE_SID
);
72 list_del_rcu(&p
->tasks
);
73 __get_cpu_var(process_counts
)--;
75 list_del_rcu(&p
->thread_group
);
76 list_del_init(&p
->sibling
);
80 * This function expects the tasklist_lock write-locked.
82 static void __exit_signal(struct task_struct
*tsk
)
84 struct signal_struct
*sig
= tsk
->signal
;
85 struct sighand_struct
*sighand
;
88 BUG_ON(!atomic_read(&sig
->count
));
90 sighand
= rcu_dereference(tsk
->sighand
);
91 spin_lock(&sighand
->siglock
);
93 posix_cpu_timers_exit(tsk
);
94 if (atomic_dec_and_test(&sig
->count
))
95 posix_cpu_timers_exit_group(tsk
);
98 * If there is any task waiting for the group exit
101 if (sig
->group_exit_task
&& atomic_read(&sig
->count
) == sig
->notify_count
)
102 wake_up_process(sig
->group_exit_task
);
104 if (tsk
== sig
->curr_target
)
105 sig
->curr_target
= next_thread(tsk
);
107 * Accumulate here the counters for all threads but the
108 * group leader as they die, so they can be added into
109 * the process-wide totals when those are taken.
110 * The group leader stays around as a zombie as long
111 * as there are other threads. When it gets reaped,
112 * the exit.c code will add its counts into these totals.
113 * We won't ever get here for the group leader, since it
114 * will have been the last reference on the signal_struct.
116 sig
->utime
= cputime_add(sig
->utime
, task_utime(tsk
));
117 sig
->stime
= cputime_add(sig
->stime
, task_stime(tsk
));
118 sig
->gtime
= cputime_add(sig
->gtime
, task_gtime(tsk
));
119 sig
->min_flt
+= tsk
->min_flt
;
120 sig
->maj_flt
+= tsk
->maj_flt
;
121 sig
->nvcsw
+= tsk
->nvcsw
;
122 sig
->nivcsw
+= tsk
->nivcsw
;
123 sig
->inblock
+= task_io_get_inblock(tsk
);
124 sig
->oublock
+= task_io_get_oublock(tsk
);
125 task_io_accounting_add(&sig
->ioac
, &tsk
->ioac
);
126 sig
->sum_sched_runtime
+= tsk
->se
.sum_exec_runtime
;
127 sig
= NULL
; /* Marker for below. */
130 __unhash_process(tsk
);
133 * Do this under ->siglock, we can race with another thread
134 * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
136 flush_sigqueue(&tsk
->pending
);
140 spin_unlock(&sighand
->siglock
);
142 __cleanup_sighand(sighand
);
143 clear_tsk_thread_flag(tsk
,TIF_SIGPENDING
);
145 flush_sigqueue(&sig
->shared_pending
);
146 taskstats_tgid_free(sig
);
148 * Make sure ->signal can't go away under rq->lock,
149 * see account_group_exec_runtime().
151 task_rq_unlock_wait(tsk
);
152 __cleanup_signal(sig
);
156 static void delayed_put_task_struct(struct rcu_head
*rhp
)
158 struct task_struct
*tsk
= container_of(rhp
, struct task_struct
, rcu
);
160 trace_sched_process_free(tsk
);
161 put_task_struct(tsk
);
165 void release_task(struct task_struct
* p
)
167 struct task_struct
*leader
;
170 tracehook_prepare_release_task(p
);
171 /* don't need to get the RCU readlock here - the process is dead and
172 * can't be modifying its own credentials */
173 atomic_dec(&__task_cred(p
)->user
->processes
);
176 write_lock_irq(&tasklist_lock
);
177 tracehook_finish_release_task(p
);
181 * If we are the last non-leader member of the thread
182 * group, and the leader is zombie, then notify the
183 * group leader's parent process. (if it wants notification.)
186 leader
= p
->group_leader
;
187 if (leader
!= p
&& thread_group_empty(leader
) && leader
->exit_state
== EXIT_ZOMBIE
) {
188 BUG_ON(task_detached(leader
));
189 do_notify_parent(leader
, leader
->exit_signal
);
191 * If we were the last child thread and the leader has
192 * exited already, and the leader's parent ignores SIGCHLD,
193 * then we are the one who should release the leader.
195 * do_notify_parent() will have marked it self-reaping in
198 zap_leader
= task_detached(leader
);
201 * This maintains the invariant that release_task()
202 * only runs on a task in EXIT_DEAD, just for sanity.
205 leader
->exit_state
= EXIT_DEAD
;
208 write_unlock_irq(&tasklist_lock
);
210 call_rcu(&p
->rcu
, delayed_put_task_struct
);
213 if (unlikely(zap_leader
))
218 * This checks not only the pgrp, but falls back on the pid if no
219 * satisfactory pgrp is found. I dunno - gdb doesn't work correctly
222 * The caller must hold rcu lock or the tasklist lock.
224 struct pid
*session_of_pgrp(struct pid
*pgrp
)
226 struct task_struct
*p
;
227 struct pid
*sid
= NULL
;
229 p
= pid_task(pgrp
, PIDTYPE_PGID
);
231 p
= pid_task(pgrp
, PIDTYPE_PID
);
233 sid
= task_session(p
);
239 * Determine if a process group is "orphaned", according to the POSIX
240 * definition in 2.2.2.52. Orphaned process groups are not to be affected
241 * by terminal-generated stop signals. Newly orphaned process groups are
242 * to receive a SIGHUP and a SIGCONT.
244 * "I ask you, have you ever known what it is to be an orphan?"
246 static int will_become_orphaned_pgrp(struct pid
*pgrp
, struct task_struct
*ignored_task
)
248 struct task_struct
*p
;
250 do_each_pid_task(pgrp
, PIDTYPE_PGID
, p
) {
251 if ((p
== ignored_task
) ||
252 (p
->exit_state
&& thread_group_empty(p
)) ||
253 is_global_init(p
->real_parent
))
256 if (task_pgrp(p
->real_parent
) != pgrp
&&
257 task_session(p
->real_parent
) == task_session(p
))
259 } while_each_pid_task(pgrp
, PIDTYPE_PGID
, p
);
264 int is_current_pgrp_orphaned(void)
268 read_lock(&tasklist_lock
);
269 retval
= will_become_orphaned_pgrp(task_pgrp(current
), NULL
);
270 read_unlock(&tasklist_lock
);
275 static int has_stopped_jobs(struct pid
*pgrp
)
278 struct task_struct
*p
;
280 do_each_pid_task(pgrp
, PIDTYPE_PGID
, p
) {
281 if (!task_is_stopped(p
))
285 } while_each_pid_task(pgrp
, PIDTYPE_PGID
, p
);
290 * Check to see if any process groups have become orphaned as
291 * a result of our exiting, and if they have any stopped jobs,
292 * send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
295 kill_orphaned_pgrp(struct task_struct
*tsk
, struct task_struct
*parent
)
297 struct pid
*pgrp
= task_pgrp(tsk
);
298 struct task_struct
*ignored_task
= tsk
;
301 /* exit: our father is in a different pgrp than
302 * we are and we were the only connection outside.
304 parent
= tsk
->real_parent
;
306 /* reparent: our child is in a different pgrp than
307 * we are, and it was the only connection outside.
311 if (task_pgrp(parent
) != pgrp
&&
312 task_session(parent
) == task_session(tsk
) &&
313 will_become_orphaned_pgrp(pgrp
, ignored_task
) &&
314 has_stopped_jobs(pgrp
)) {
315 __kill_pgrp_info(SIGHUP
, SEND_SIG_PRIV
, pgrp
);
316 __kill_pgrp_info(SIGCONT
, SEND_SIG_PRIV
, pgrp
);
321 * reparent_to_kthreadd - Reparent the calling kernel thread to kthreadd
323 * If a kernel thread is launched as a result of a system call, or if
324 * it ever exits, it should generally reparent itself to kthreadd so it
325 * isn't in the way of other processes and is correctly cleaned up on exit.
327 * The various task state such as scheduling policy and priority may have
328 * been inherited from a user process, so we reset them to sane values here.
330 * NOTE that reparent_to_kthreadd() gives the caller full capabilities.
332 static void reparent_to_kthreadd(void)
334 write_lock_irq(&tasklist_lock
);
336 ptrace_unlink(current
);
337 /* Reparent to init */
338 current
->real_parent
= current
->parent
= kthreadd_task
;
339 list_move_tail(¤t
->sibling
, ¤t
->real_parent
->children
);
341 /* Set the exit signal to SIGCHLD so we signal init on exit */
342 current
->exit_signal
= SIGCHLD
;
344 if (task_nice(current
) < 0)
345 set_user_nice(current
, 0);
349 memcpy(current
->signal
->rlim
, init_task
.signal
->rlim
,
350 sizeof(current
->signal
->rlim
));
352 atomic_inc(&init_cred
.usage
);
353 commit_creds(&init_cred
);
354 write_unlock_irq(&tasklist_lock
);
357 void __set_special_pids(struct pid
*pid
)
359 struct task_struct
*curr
= current
->group_leader
;
360 pid_t nr
= pid_nr(pid
);
362 if (task_session(curr
) != pid
) {
363 change_pid(curr
, PIDTYPE_SID
, pid
);
364 set_task_session(curr
, nr
);
366 if (task_pgrp(curr
) != pid
) {
367 change_pid(curr
, PIDTYPE_PGID
, pid
);
368 set_task_pgrp(curr
, nr
);
372 static void set_special_pids(struct pid
*pid
)
374 write_lock_irq(&tasklist_lock
);
375 __set_special_pids(pid
);
376 write_unlock_irq(&tasklist_lock
);
380 * Let kernel threads use this to say that they
381 * allow a certain signal (since daemonize() will
382 * have disabled all of them by default).
384 int allow_signal(int sig
)
386 if (!valid_signal(sig
) || sig
< 1)
389 spin_lock_irq(¤t
->sighand
->siglock
);
390 sigdelset(¤t
->blocked
, sig
);
392 /* Kernel threads handle their own signals.
393 Let the signal code know it'll be handled, so
394 that they don't get converted to SIGKILL or
395 just silently dropped */
396 current
->sighand
->action
[(sig
)-1].sa
.sa_handler
= (void __user
*)2;
399 spin_unlock_irq(¤t
->sighand
->siglock
);
403 EXPORT_SYMBOL(allow_signal
);
405 int disallow_signal(int sig
)
407 if (!valid_signal(sig
) || sig
< 1)
410 spin_lock_irq(¤t
->sighand
->siglock
);
411 current
->sighand
->action
[(sig
)-1].sa
.sa_handler
= SIG_IGN
;
413 spin_unlock_irq(¤t
->sighand
->siglock
);
417 EXPORT_SYMBOL(disallow_signal
);
420 * Put all the gunge required to become a kernel thread without
421 * attached user resources in one place where it belongs.
424 void daemonize(const char *name
, ...)
427 struct fs_struct
*fs
;
430 va_start(args
, name
);
431 vsnprintf(current
->comm
, sizeof(current
->comm
), name
, args
);
435 * If we were started as result of loading a module, close all of the
436 * user space pages. We don't need them, and if we didn't close them
437 * they would be locked into memory.
441 * We don't want to have TIF_FREEZE set if the system-wide hibernation
442 * or suspend transition begins right now.
444 current
->flags
|= (PF_NOFREEZE
| PF_KTHREAD
);
446 if (current
->nsproxy
!= &init_nsproxy
) {
447 get_nsproxy(&init_nsproxy
);
448 switch_task_namespaces(current
, &init_nsproxy
);
450 set_special_pids(&init_struct_pid
);
451 proc_clear_tty(current
);
453 /* Block and flush all signals */
454 sigfillset(&blocked
);
455 sigprocmask(SIG_BLOCK
, &blocked
, NULL
);
456 flush_signals(current
);
458 /* Become as one with the init task */
460 exit_fs(current
); /* current->fs->count--; */
463 atomic_inc(&fs
->count
);
466 current
->files
= init_task
.files
;
467 atomic_inc(¤t
->files
->count
);
469 reparent_to_kthreadd();
472 EXPORT_SYMBOL(daemonize
);
474 static void close_files(struct files_struct
* files
)
482 * It is safe to dereference the fd table without RCU or
483 * ->file_lock because this is the last reference to the
486 fdt
= files_fdtable(files
);
490 if (i
>= fdt
->max_fds
)
492 set
= fdt
->open_fds
->fds_bits
[j
++];
495 struct file
* file
= xchg(&fdt
->fd
[i
], NULL
);
497 filp_close(file
, files
);
507 struct files_struct
*get_files_struct(struct task_struct
*task
)
509 struct files_struct
*files
;
514 atomic_inc(&files
->count
);
520 void put_files_struct(struct files_struct
*files
)
524 if (atomic_dec_and_test(&files
->count
)) {
527 * Free the fd and fdset arrays if we expanded them.
528 * If the fdtable was embedded, pass files for freeing
529 * at the end of the RCU grace period. Otherwise,
530 * you can free files immediately.
532 fdt
= files_fdtable(files
);
533 if (fdt
!= &files
->fdtab
)
534 kmem_cache_free(files_cachep
, files
);
539 void reset_files_struct(struct files_struct
*files
)
541 struct task_struct
*tsk
= current
;
542 struct files_struct
*old
;
548 put_files_struct(old
);
551 void exit_files(struct task_struct
*tsk
)
553 struct files_struct
* files
= tsk
->files
;
559 put_files_struct(files
);
563 void put_fs_struct(struct fs_struct
*fs
)
565 /* No need to hold fs->lock if we are killing it */
566 if (atomic_dec_and_test(&fs
->count
)) {
569 kmem_cache_free(fs_cachep
, fs
);
573 void exit_fs(struct task_struct
*tsk
)
575 struct fs_struct
* fs
= tsk
->fs
;
585 EXPORT_SYMBOL_GPL(exit_fs
);
587 #ifdef CONFIG_MM_OWNER
589 * Task p is exiting and it owned mm, lets find a new owner for it
592 mm_need_new_owner(struct mm_struct
*mm
, struct task_struct
*p
)
595 * If there are other users of the mm and the owner (us) is exiting
596 * we need to find a new owner to take on the responsibility.
598 if (atomic_read(&mm
->mm_users
) <= 1)
605 void mm_update_next_owner(struct mm_struct
*mm
)
607 struct task_struct
*c
, *g
, *p
= current
;
610 if (!mm_need_new_owner(mm
, p
))
613 read_lock(&tasklist_lock
);
615 * Search in the children
617 list_for_each_entry(c
, &p
->children
, sibling
) {
619 goto assign_new_owner
;
623 * Search in the siblings
625 list_for_each_entry(c
, &p
->parent
->children
, sibling
) {
627 goto assign_new_owner
;
631 * Search through everything else. We should not get
634 do_each_thread(g
, c
) {
636 goto assign_new_owner
;
637 } while_each_thread(g
, c
);
639 read_unlock(&tasklist_lock
);
641 * We found no owner yet mm_users > 1: this implies that we are
642 * most likely racing with swapoff (try_to_unuse()) or /proc or
643 * ptrace or page migration (get_task_mm()). Mark owner as NULL.
652 * The task_lock protects c->mm from changing.
653 * We always want mm->owner->mm == mm
657 * Delay read_unlock() till we have the task_lock()
658 * to ensure that c does not slip away underneath us
660 read_unlock(&tasklist_lock
);
670 #endif /* CONFIG_MM_OWNER */
673 * Turn us into a lazy TLB process if we
676 static void exit_mm(struct task_struct
* tsk
)
678 struct mm_struct
*mm
= tsk
->mm
;
679 struct core_state
*core_state
;
685 * Serialize with any possible pending coredump.
686 * We must hold mmap_sem around checking core_state
687 * and clearing tsk->mm. The core-inducing thread
688 * will increment ->nr_threads for each thread in the
689 * group with ->mm != NULL.
691 down_read(&mm
->mmap_sem
);
692 core_state
= mm
->core_state
;
694 struct core_thread self
;
695 up_read(&mm
->mmap_sem
);
698 self
.next
= xchg(&core_state
->dumper
.next
, &self
);
700 * Implies mb(), the result of xchg() must be visible
701 * to core_state->dumper.
703 if (atomic_dec_and_test(&core_state
->nr_threads
))
704 complete(&core_state
->startup
);
707 set_task_state(tsk
, TASK_UNINTERRUPTIBLE
);
708 if (!self
.task
) /* see coredump_finish() */
712 __set_task_state(tsk
, TASK_RUNNING
);
713 down_read(&mm
->mmap_sem
);
715 atomic_inc(&mm
->mm_count
);
716 BUG_ON(mm
!= tsk
->active_mm
);
717 /* more a memory barrier than a real lock */
720 up_read(&mm
->mmap_sem
);
721 enter_lazy_tlb(mm
, current
);
722 /* We don't want this task to be frozen prematurely */
723 clear_freeze_flag(tsk
);
725 mm_update_next_owner(mm
);
730 * When we die, we re-parent all our children.
731 * Try to give them to another thread in our thread
732 * group, and if no such member exists, give it to
733 * the child reaper process (ie "init") in our pid
736 static struct task_struct
*find_new_reaper(struct task_struct
*father
)
738 struct pid_namespace
*pid_ns
= task_active_pid_ns(father
);
739 struct task_struct
*thread
;
742 while_each_thread(father
, thread
) {
743 if (thread
->flags
& PF_EXITING
)
745 if (unlikely(pid_ns
->child_reaper
== father
))
746 pid_ns
->child_reaper
= thread
;
750 if (unlikely(pid_ns
->child_reaper
== father
)) {
751 write_unlock_irq(&tasklist_lock
);
752 if (unlikely(pid_ns
== &init_pid_ns
))
753 panic("Attempted to kill init!");
755 zap_pid_ns_processes(pid_ns
);
756 write_lock_irq(&tasklist_lock
);
758 * We can not clear ->child_reaper or leave it alone.
759 * There may by stealth EXIT_DEAD tasks on ->children,
760 * forget_original_parent() must move them somewhere.
762 pid_ns
->child_reaper
= init_pid_ns
.child_reaper
;
765 return pid_ns
->child_reaper
;
769 * Any that need to be release_task'd are put on the @dead list.
771 static void reparent_thread(struct task_struct
*father
, struct task_struct
*p
,
772 struct list_head
*dead
)
774 if (p
->pdeath_signal
)
775 group_send_sig_info(p
->pdeath_signal
, SEND_SIG_NOINFO
, p
);
777 list_move_tail(&p
->sibling
, &p
->real_parent
->children
);
779 if (task_detached(p
))
782 * If this is a threaded reparent there is no need to
783 * notify anyone anything has happened.
785 if (same_thread_group(p
->real_parent
, father
))
788 /* We don't want people slaying init. */
789 p
->exit_signal
= SIGCHLD
;
791 /* If it has exited notify the new parent about this child's death. */
793 p
->exit_state
== EXIT_ZOMBIE
&& thread_group_empty(p
)) {
794 do_notify_parent(p
, p
->exit_signal
);
795 if (task_detached(p
)) {
796 p
->exit_state
= EXIT_DEAD
;
797 list_move_tail(&p
->sibling
, dead
);
801 kill_orphaned_pgrp(p
, father
);
804 static void forget_original_parent(struct task_struct
*father
)
806 struct task_struct
*p
, *n
, *reaper
;
807 LIST_HEAD(dead_children
);
811 write_lock_irq(&tasklist_lock
);
812 reaper
= find_new_reaper(father
);
814 list_for_each_entry_safe(p
, n
, &father
->children
, sibling
) {
815 p
->real_parent
= reaper
;
816 if (p
->parent
== father
) {
818 p
->parent
= p
->real_parent
;
820 reparent_thread(father
, p
, &dead_children
);
822 write_unlock_irq(&tasklist_lock
);
824 BUG_ON(!list_empty(&father
->children
));
826 list_for_each_entry_safe(p
, n
, &dead_children
, sibling
) {
827 list_del_init(&p
->sibling
);
833 * Send signals to all our closest relatives so that they know
834 * to properly mourn us..
836 static void exit_notify(struct task_struct
*tsk
, int group_dead
)
842 * This does two things:
844 * A. Make init inherit all the child processes
845 * B. Check to see if any process groups have become orphaned
846 * as a result of our exiting, and if they have any stopped
847 * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
849 forget_original_parent(tsk
);
850 exit_task_namespaces(tsk
);
852 write_lock_irq(&tasklist_lock
);
854 kill_orphaned_pgrp(tsk
->group_leader
, NULL
);
856 /* Let father know we died
858 * Thread signals are configurable, but you aren't going to use
859 * that to send signals to arbitary processes.
860 * That stops right now.
862 * If the parent exec id doesn't match the exec id we saved
863 * when we started then we know the parent has changed security
866 * If our self_exec id doesn't match our parent_exec_id then
867 * we have changed execution domain as these two values started
868 * the same after a fork.
870 if (tsk
->exit_signal
!= SIGCHLD
&& !task_detached(tsk
) &&
871 (tsk
->parent_exec_id
!= tsk
->real_parent
->self_exec_id
||
872 tsk
->self_exec_id
!= tsk
->parent_exec_id
) &&
874 tsk
->exit_signal
= SIGCHLD
;
876 signal
= tracehook_notify_death(tsk
, &cookie
, group_dead
);
878 signal
= do_notify_parent(tsk
, signal
);
880 tsk
->exit_state
= signal
== DEATH_REAP
? EXIT_DEAD
: EXIT_ZOMBIE
;
882 /* mt-exec, de_thread() is waiting for us */
883 if (thread_group_leader(tsk
) &&
884 tsk
->signal
->group_exit_task
&&
885 tsk
->signal
->notify_count
< 0)
886 wake_up_process(tsk
->signal
->group_exit_task
);
888 write_unlock_irq(&tasklist_lock
);
890 tracehook_report_death(tsk
, signal
, cookie
, group_dead
);
892 /* If the process is dead, release it - nobody will wait for it */
893 if (signal
== DEATH_REAP
)
897 #ifdef CONFIG_DEBUG_STACK_USAGE
898 static void check_stack_usage(void)
900 static DEFINE_SPINLOCK(low_water_lock
);
901 static int lowest_to_date
= THREAD_SIZE
;
904 free
= stack_not_used(current
);
906 if (free
>= lowest_to_date
)
909 spin_lock(&low_water_lock
);
910 if (free
< lowest_to_date
) {
911 printk(KERN_WARNING
"%s used greatest stack depth: %lu bytes "
913 current
->comm
, free
);
914 lowest_to_date
= free
;
916 spin_unlock(&low_water_lock
);
919 static inline void check_stack_usage(void) {}
922 NORET_TYPE
void do_exit(long code
)
924 struct task_struct
*tsk
= current
;
927 profile_task_exit(tsk
);
929 WARN_ON(atomic_read(&tsk
->fs_excl
));
931 if (unlikely(in_interrupt()))
932 panic("Aiee, killing interrupt handler!");
933 if (unlikely(!tsk
->pid
))
934 panic("Attempted to kill the idle task!");
936 tracehook_report_exit(&code
);
939 * We're taking recursive faults here in do_exit. Safest is to just
940 * leave this task alone and wait for reboot.
942 if (unlikely(tsk
->flags
& PF_EXITING
)) {
944 "Fixing recursive fault but reboot is needed!\n");
946 * We can do this unlocked here. The futex code uses
947 * this flag just to verify whether the pi state
948 * cleanup has been done or not. In the worst case it
949 * loops once more. We pretend that the cleanup was
950 * done as there is no way to return. Either the
951 * OWNER_DIED bit is set by now or we push the blocked
952 * task into the wait for ever nirwana as well.
954 tsk
->flags
|= PF_EXITPIDONE
;
955 set_current_state(TASK_UNINTERRUPTIBLE
);
959 exit_signals(tsk
); /* sets PF_EXITING */
961 * tsk->flags are checked in the futex code to protect against
962 * an exiting task cleaning up the robust pi futexes.
965 spin_unlock_wait(&tsk
->pi_lock
);
967 if (unlikely(in_atomic()))
968 printk(KERN_INFO
"note: %s[%d] exited with preempt_count %d\n",
969 current
->comm
, task_pid_nr(current
),
972 acct_update_integrals(tsk
);
974 group_dead
= atomic_dec_and_test(&tsk
->signal
->live
);
976 hrtimer_cancel(&tsk
->signal
->real_timer
);
977 exit_itimers(tsk
->signal
);
979 acct_collect(code
, group_dead
);
982 if (unlikely(tsk
->audit_context
))
985 tsk
->exit_code
= code
;
986 taskstats_exit(tsk
, group_dead
);
992 trace_sched_process_exit(tsk
);
1001 if (group_dead
&& tsk
->signal
->leader
)
1002 disassociate_ctty(1);
1004 module_put(task_thread_info(tsk
)->exec_domain
->module
);
1006 module_put(tsk
->binfmt
->module
);
1008 proc_exit_connector(tsk
);
1009 exit_notify(tsk
, group_dead
);
1011 mpol_put(tsk
->mempolicy
);
1012 tsk
->mempolicy
= NULL
;
1016 * This must happen late, after the PID is not
1019 if (unlikely(!list_empty(&tsk
->pi_state_list
)))
1020 exit_pi_state_list(tsk
);
1021 if (unlikely(current
->pi_state_cache
))
1022 kfree(current
->pi_state_cache
);
1025 * Make sure we are holding no locks:
1027 debug_check_no_locks_held(tsk
);
1029 * We can do this unlocked here. The futex code uses this flag
1030 * just to verify whether the pi state cleanup has been done
1031 * or not. In the worst case it loops once more.
1033 tsk
->flags
|= PF_EXITPIDONE
;
1035 if (tsk
->io_context
)
1038 if (tsk
->splice_pipe
)
1039 __free_pipe_info(tsk
->splice_pipe
);
1042 /* causes final put_task_struct in finish_task_switch(). */
1043 tsk
->state
= TASK_DEAD
;
1046 /* Avoid "noreturn function does return". */
1048 cpu_relax(); /* For when BUG is null */
1051 EXPORT_SYMBOL_GPL(do_exit
);
1053 NORET_TYPE
void complete_and_exit(struct completion
*comp
, long code
)
1061 EXPORT_SYMBOL(complete_and_exit
);
1063 SYSCALL_DEFINE1(exit
, int, error_code
)
1065 do_exit((error_code
&0xff)<<8);
1069 * Take down every thread in the group. This is called by fatal signals
1070 * as well as by sys_exit_group (below).
1073 do_group_exit(int exit_code
)
1075 struct signal_struct
*sig
= current
->signal
;
1077 BUG_ON(exit_code
& 0x80); /* core dumps don't get here */
1079 if (signal_group_exit(sig
))
1080 exit_code
= sig
->group_exit_code
;
1081 else if (!thread_group_empty(current
)) {
1082 struct sighand_struct
*const sighand
= current
->sighand
;
1083 spin_lock_irq(&sighand
->siglock
);
1084 if (signal_group_exit(sig
))
1085 /* Another thread got here before we took the lock. */
1086 exit_code
= sig
->group_exit_code
;
1088 sig
->group_exit_code
= exit_code
;
1089 sig
->flags
= SIGNAL_GROUP_EXIT
;
1090 zap_other_threads(current
);
1092 spin_unlock_irq(&sighand
->siglock
);
1100 * this kills every thread in the thread group. Note that any externally
1101 * wait4()-ing process will get the correct exit code - even if this
1102 * thread is not the thread group leader.
1104 SYSCALL_DEFINE1(exit_group
, int, error_code
)
1106 do_group_exit((error_code
& 0xff) << 8);
1111 static struct pid
*task_pid_type(struct task_struct
*task
, enum pid_type type
)
1113 struct pid
*pid
= NULL
;
1114 if (type
== PIDTYPE_PID
)
1115 pid
= task
->pids
[type
].pid
;
1116 else if (type
< PIDTYPE_MAX
)
1117 pid
= task
->group_leader
->pids
[type
].pid
;
1121 static int eligible_child(enum pid_type type
, struct pid
*pid
, int options
,
1122 struct task_struct
*p
)
1126 if (type
< PIDTYPE_MAX
) {
1127 if (task_pid_type(p
, type
) != pid
)
1131 /* Wait for all children (clone and not) if __WALL is set;
1132 * otherwise, wait for clone children *only* if __WCLONE is
1133 * set; otherwise, wait for non-clone children *only*. (Note:
1134 * A "clone" child here is one that reports to its parent
1135 * using a signal other than SIGCHLD.) */
1136 if (((p
->exit_signal
!= SIGCHLD
) ^ ((options
& __WCLONE
) != 0))
1137 && !(options
& __WALL
))
1140 err
= security_task_wait(p
);
1147 static int wait_noreap_copyout(struct task_struct
*p
, pid_t pid
, uid_t uid
,
1148 int why
, int status
,
1149 struct siginfo __user
*infop
,
1150 struct rusage __user
*rusagep
)
1152 int retval
= rusagep
? getrusage(p
, RUSAGE_BOTH
, rusagep
) : 0;
1156 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1158 retval
= put_user(0, &infop
->si_errno
);
1160 retval
= put_user((short)why
, &infop
->si_code
);
1162 retval
= put_user(pid
, &infop
->si_pid
);
1164 retval
= put_user(uid
, &infop
->si_uid
);
1166 retval
= put_user(status
, &infop
->si_status
);
1173 * Handle sys_wait4 work for one task in state EXIT_ZOMBIE. We hold
1174 * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
1175 * the lock and this task is uninteresting. If we return nonzero, we have
1176 * released the lock and the system call should return.
1178 static int wait_task_zombie(struct task_struct
*p
, int options
,
1179 struct siginfo __user
*infop
,
1180 int __user
*stat_addr
, struct rusage __user
*ru
)
1182 unsigned long state
;
1183 int retval
, status
, traced
;
1184 pid_t pid
= task_pid_vnr(p
);
1185 uid_t uid
= __task_cred(p
)->uid
;
1187 if (!likely(options
& WEXITED
))
1190 if (unlikely(options
& WNOWAIT
)) {
1191 int exit_code
= p
->exit_code
;
1195 read_unlock(&tasklist_lock
);
1196 if ((exit_code
& 0x7f) == 0) {
1198 status
= exit_code
>> 8;
1200 why
= (exit_code
& 0x80) ? CLD_DUMPED
: CLD_KILLED
;
1201 status
= exit_code
& 0x7f;
1203 return wait_noreap_copyout(p
, pid
, uid
, why
,
1208 * Try to move the task's state to DEAD
1209 * only one thread is allowed to do this:
1211 state
= xchg(&p
->exit_state
, EXIT_DEAD
);
1212 if (state
!= EXIT_ZOMBIE
) {
1213 BUG_ON(state
!= EXIT_DEAD
);
1217 traced
= ptrace_reparented(p
);
1219 if (likely(!traced
)) {
1220 struct signal_struct
*psig
;
1221 struct signal_struct
*sig
;
1222 struct task_cputime cputime
;
1225 * The resource counters for the group leader are in its
1226 * own task_struct. Those for dead threads in the group
1227 * are in its signal_struct, as are those for the child
1228 * processes it has previously reaped. All these
1229 * accumulate in the parent's signal_struct c* fields.
1231 * We don't bother to take a lock here to protect these
1232 * p->signal fields, because they are only touched by
1233 * __exit_signal, which runs with tasklist_lock
1234 * write-locked anyway, and so is excluded here. We do
1235 * need to protect the access to p->parent->signal fields,
1236 * as other threads in the parent group can be right
1237 * here reaping other children at the same time.
1239 * We use thread_group_cputime() to get times for the thread
1240 * group, which consolidates times for all threads in the
1241 * group including the group leader.
1243 thread_group_cputime(p
, &cputime
);
1244 spin_lock_irq(&p
->parent
->sighand
->siglock
);
1245 psig
= p
->parent
->signal
;
1248 cputime_add(psig
->cutime
,
1249 cputime_add(cputime
.utime
,
1252 cputime_add(psig
->cstime
,
1253 cputime_add(cputime
.stime
,
1256 cputime_add(psig
->cgtime
,
1257 cputime_add(p
->gtime
,
1258 cputime_add(sig
->gtime
,
1261 p
->min_flt
+ sig
->min_flt
+ sig
->cmin_flt
;
1263 p
->maj_flt
+ sig
->maj_flt
+ sig
->cmaj_flt
;
1265 p
->nvcsw
+ sig
->nvcsw
+ sig
->cnvcsw
;
1267 p
->nivcsw
+ sig
->nivcsw
+ sig
->cnivcsw
;
1269 task_io_get_inblock(p
) +
1270 sig
->inblock
+ sig
->cinblock
;
1272 task_io_get_oublock(p
) +
1273 sig
->oublock
+ sig
->coublock
;
1274 task_io_accounting_add(&psig
->ioac
, &p
->ioac
);
1275 task_io_accounting_add(&psig
->ioac
, &sig
->ioac
);
1276 spin_unlock_irq(&p
->parent
->sighand
->siglock
);
1280 * Now we are sure this task is interesting, and no other
1281 * thread can reap it because we set its state to EXIT_DEAD.
1283 read_unlock(&tasklist_lock
);
1285 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1286 status
= (p
->signal
->flags
& SIGNAL_GROUP_EXIT
)
1287 ? p
->signal
->group_exit_code
: p
->exit_code
;
1288 if (!retval
&& stat_addr
)
1289 retval
= put_user(status
, stat_addr
);
1290 if (!retval
&& infop
)
1291 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1292 if (!retval
&& infop
)
1293 retval
= put_user(0, &infop
->si_errno
);
1294 if (!retval
&& infop
) {
1297 if ((status
& 0x7f) == 0) {
1301 why
= (status
& 0x80) ? CLD_DUMPED
: CLD_KILLED
;
1304 retval
= put_user((short)why
, &infop
->si_code
);
1306 retval
= put_user(status
, &infop
->si_status
);
1308 if (!retval
&& infop
)
1309 retval
= put_user(pid
, &infop
->si_pid
);
1310 if (!retval
&& infop
)
1311 retval
= put_user(uid
, &infop
->si_uid
);
1316 write_lock_irq(&tasklist_lock
);
1317 /* We dropped tasklist, ptracer could die and untrace */
1320 * If this is not a detached task, notify the parent.
1321 * If it's still not detached after that, don't release
1324 if (!task_detached(p
)) {
1325 do_notify_parent(p
, p
->exit_signal
);
1326 if (!task_detached(p
)) {
1327 p
->exit_state
= EXIT_ZOMBIE
;
1331 write_unlock_irq(&tasklist_lock
);
1339 static int *task_stopped_code(struct task_struct
*p
, bool ptrace
)
1342 if (task_is_stopped_or_traced(p
))
1343 return &p
->exit_code
;
1345 if (p
->signal
->flags
& SIGNAL_STOP_STOPPED
)
1346 return &p
->signal
->group_exit_code
;
1352 * Handle sys_wait4 work for one task in state TASK_STOPPED. We hold
1353 * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
1354 * the lock and this task is uninteresting. If we return nonzero, we have
1355 * released the lock and the system call should return.
1357 static int wait_task_stopped(int ptrace
, struct task_struct
*p
,
1358 int options
, struct siginfo __user
*infop
,
1359 int __user
*stat_addr
, struct rusage __user
*ru
)
1361 int retval
, exit_code
, *p_code
, why
;
1362 uid_t uid
= 0; /* unneeded, required by compiler */
1365 if (!(options
& WUNTRACED
))
1369 spin_lock_irq(&p
->sighand
->siglock
);
1371 p_code
= task_stopped_code(p
, ptrace
);
1372 if (unlikely(!p_code
))
1375 exit_code
= *p_code
;
1379 if (!unlikely(options
& WNOWAIT
))
1382 /* don't need the RCU readlock here as we're holding a spinlock */
1383 uid
= __task_cred(p
)->uid
;
1385 spin_unlock_irq(&p
->sighand
->siglock
);
1390 * Now we are pretty sure this task is interesting.
1391 * Make sure it doesn't get reaped out from under us while we
1392 * give up the lock and then examine it below. We don't want to
1393 * keep holding onto the tasklist_lock while we call getrusage and
1394 * possibly take page faults for user memory.
1397 pid
= task_pid_vnr(p
);
1398 why
= ptrace
? CLD_TRAPPED
: CLD_STOPPED
;
1399 read_unlock(&tasklist_lock
);
1401 if (unlikely(options
& WNOWAIT
))
1402 return wait_noreap_copyout(p
, pid
, uid
,
1406 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1407 if (!retval
&& stat_addr
)
1408 retval
= put_user((exit_code
<< 8) | 0x7f, stat_addr
);
1409 if (!retval
&& infop
)
1410 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1411 if (!retval
&& infop
)
1412 retval
= put_user(0, &infop
->si_errno
);
1413 if (!retval
&& infop
)
1414 retval
= put_user((short)why
, &infop
->si_code
);
1415 if (!retval
&& infop
)
1416 retval
= put_user(exit_code
, &infop
->si_status
);
1417 if (!retval
&& infop
)
1418 retval
= put_user(pid
, &infop
->si_pid
);
1419 if (!retval
&& infop
)
1420 retval
= put_user(uid
, &infop
->si_uid
);
1430 * Handle do_wait work for one task in a live, non-stopped state.
1431 * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
1432 * the lock and this task is uninteresting. If we return nonzero, we have
1433 * released the lock and the system call should return.
1435 static int wait_task_continued(struct task_struct
*p
, int options
,
1436 struct siginfo __user
*infop
,
1437 int __user
*stat_addr
, struct rusage __user
*ru
)
1443 if (!unlikely(options
& WCONTINUED
))
1446 if (!(p
->signal
->flags
& SIGNAL_STOP_CONTINUED
))
1449 spin_lock_irq(&p
->sighand
->siglock
);
1450 /* Re-check with the lock held. */
1451 if (!(p
->signal
->flags
& SIGNAL_STOP_CONTINUED
)) {
1452 spin_unlock_irq(&p
->sighand
->siglock
);
1455 if (!unlikely(options
& WNOWAIT
))
1456 p
->signal
->flags
&= ~SIGNAL_STOP_CONTINUED
;
1457 uid
= __task_cred(p
)->uid
;
1458 spin_unlock_irq(&p
->sighand
->siglock
);
1460 pid
= task_pid_vnr(p
);
1462 read_unlock(&tasklist_lock
);
1465 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1467 if (!retval
&& stat_addr
)
1468 retval
= put_user(0xffff, stat_addr
);
1472 retval
= wait_noreap_copyout(p
, pid
, uid
,
1473 CLD_CONTINUED
, SIGCONT
,
1475 BUG_ON(retval
== 0);
1482 * Consider @p for a wait by @parent.
1484 * -ECHILD should be in *@notask_error before the first call.
1485 * Returns nonzero for a final return, when we have unlocked tasklist_lock.
1486 * Returns zero if the search for a child should continue;
1487 * then *@notask_error is 0 if @p is an eligible child,
1488 * or another error from security_task_wait(), or still -ECHILD.
1490 static int wait_consider_task(struct task_struct
*parent
, int ptrace
,
1491 struct task_struct
*p
, int *notask_error
,
1492 enum pid_type type
, struct pid
*pid
, int options
,
1493 struct siginfo __user
*infop
,
1494 int __user
*stat_addr
, struct rusage __user
*ru
)
1496 int ret
= eligible_child(type
, pid
, options
, p
);
1500 if (unlikely(ret
< 0)) {
1502 * If we have not yet seen any eligible child,
1503 * then let this error code replace -ECHILD.
1504 * A permission error will give the user a clue
1505 * to look for security policy problems, rather
1506 * than for mysterious wait bugs.
1509 *notask_error
= ret
;
1512 if (likely(!ptrace
) && unlikely(p
->ptrace
)) {
1514 * This child is hidden by ptrace.
1515 * We aren't allowed to see it now, but eventually we will.
1521 if (p
->exit_state
== EXIT_DEAD
)
1525 * We don't reap group leaders with subthreads.
1527 if (p
->exit_state
== EXIT_ZOMBIE
&& !delay_group_leader(p
))
1528 return wait_task_zombie(p
, options
, infop
, stat_addr
, ru
);
1531 * It's stopped or running now, so it might
1532 * later continue, exit, or stop again.
1536 if (task_stopped_code(p
, ptrace
))
1537 return wait_task_stopped(ptrace
, p
, options
,
1538 infop
, stat_addr
, ru
);
1540 return wait_task_continued(p
, options
, infop
, stat_addr
, ru
);
1544 * Do the work of do_wait() for one thread in the group, @tsk.
1546 * -ECHILD should be in *@notask_error before the first call.
1547 * Returns nonzero for a final return, when we have unlocked tasklist_lock.
1548 * Returns zero if the search for a child should continue; then
1549 * *@notask_error is 0 if there were any eligible children,
1550 * or another error from security_task_wait(), or still -ECHILD.
1552 static int do_wait_thread(struct task_struct
*tsk
, int *notask_error
,
1553 enum pid_type type
, struct pid
*pid
, int options
,
1554 struct siginfo __user
*infop
, int __user
*stat_addr
,
1555 struct rusage __user
*ru
)
1557 struct task_struct
*p
;
1559 list_for_each_entry(p
, &tsk
->children
, sibling
) {
1561 * Do not consider detached threads.
1563 if (!task_detached(p
)) {
1564 int ret
= wait_consider_task(tsk
, 0, p
, notask_error
,
1566 infop
, stat_addr
, ru
);
1575 static int ptrace_do_wait(struct task_struct
*tsk
, int *notask_error
,
1576 enum pid_type type
, struct pid
*pid
, int options
,
1577 struct siginfo __user
*infop
, int __user
*stat_addr
,
1578 struct rusage __user
*ru
)
1580 struct task_struct
*p
;
1583 * Traditionally we see ptrace'd stopped tasks regardless of options.
1585 options
|= WUNTRACED
;
1587 list_for_each_entry(p
, &tsk
->ptraced
, ptrace_entry
) {
1588 int ret
= wait_consider_task(tsk
, 1, p
, notask_error
,
1590 infop
, stat_addr
, ru
);
1598 static long do_wait(enum pid_type type
, struct pid
*pid
, int options
,
1599 struct siginfo __user
*infop
, int __user
*stat_addr
,
1600 struct rusage __user
*ru
)
1602 DECLARE_WAITQUEUE(wait
, current
);
1603 struct task_struct
*tsk
;
1606 trace_sched_process_wait(pid
);
1608 add_wait_queue(¤t
->signal
->wait_chldexit
,&wait
);
1611 * If there is nothing that can match our critiera just get out.
1612 * We will clear @retval to zero if we see any child that might later
1613 * match our criteria, even if we are not able to reap it yet.
1616 if ((type
< PIDTYPE_MAX
) && (!pid
|| hlist_empty(&pid
->tasks
[type
])))
1619 current
->state
= TASK_INTERRUPTIBLE
;
1620 read_lock(&tasklist_lock
);
1623 int tsk_result
= do_wait_thread(tsk
, &retval
,
1625 infop
, stat_addr
, ru
);
1627 tsk_result
= ptrace_do_wait(tsk
, &retval
,
1629 infop
, stat_addr
, ru
);
1632 * tasklist_lock is unlocked and we have a final result.
1634 retval
= tsk_result
;
1638 if (options
& __WNOTHREAD
)
1640 tsk
= next_thread(tsk
);
1641 BUG_ON(tsk
->signal
!= current
->signal
);
1642 } while (tsk
!= current
);
1643 read_unlock(&tasklist_lock
);
1645 if (!retval
&& !(options
& WNOHANG
)) {
1646 retval
= -ERESTARTSYS
;
1647 if (!signal_pending(current
)) {
1654 current
->state
= TASK_RUNNING
;
1655 remove_wait_queue(¤t
->signal
->wait_chldexit
,&wait
);
1661 * For a WNOHANG return, clear out all the fields
1662 * we would set so the user can easily tell the
1666 retval
= put_user(0, &infop
->si_signo
);
1668 retval
= put_user(0, &infop
->si_errno
);
1670 retval
= put_user(0, &infop
->si_code
);
1672 retval
= put_user(0, &infop
->si_pid
);
1674 retval
= put_user(0, &infop
->si_uid
);
1676 retval
= put_user(0, &infop
->si_status
);
1682 SYSCALL_DEFINE5(waitid
, int, which
, pid_t
, upid
, struct siginfo __user
*,
1683 infop
, int, options
, struct rusage __user
*, ru
)
1685 struct pid
*pid
= NULL
;
1689 if (options
& ~(WNOHANG
|WNOWAIT
|WEXITED
|WSTOPPED
|WCONTINUED
))
1691 if (!(options
& (WEXITED
|WSTOPPED
|WCONTINUED
)))
1704 type
= PIDTYPE_PGID
;
1712 if (type
< PIDTYPE_MAX
)
1713 pid
= find_get_pid(upid
);
1714 ret
= do_wait(type
, pid
, options
, infop
, NULL
, ru
);
1717 /* avoid REGPARM breakage on x86: */
1718 asmlinkage_protect(5, ret
, which
, upid
, infop
, options
, ru
);
1722 SYSCALL_DEFINE4(wait4
, pid_t
, upid
, int __user
*, stat_addr
,
1723 int, options
, struct rusage __user
*, ru
)
1725 struct pid
*pid
= NULL
;
1729 if (options
& ~(WNOHANG
|WUNTRACED
|WCONTINUED
|
1730 __WNOTHREAD
|__WCLONE
|__WALL
))
1735 else if (upid
< 0) {
1736 type
= PIDTYPE_PGID
;
1737 pid
= find_get_pid(-upid
);
1738 } else if (upid
== 0) {
1739 type
= PIDTYPE_PGID
;
1740 pid
= get_pid(task_pgrp(current
));
1741 } else /* upid > 0 */ {
1743 pid
= find_get_pid(upid
);
1746 ret
= do_wait(type
, pid
, options
| WEXITED
, NULL
, stat_addr
, ru
);
1749 /* avoid REGPARM breakage on x86: */
1750 asmlinkage_protect(4, ret
, upid
, stat_addr
, options
, ru
);
1754 #ifdef __ARCH_WANT_SYS_WAITPID
1757 * sys_waitpid() remains for compatibility. waitpid() should be
1758 * implemented by calling sys_wait4() from libc.a.
1760 SYSCALL_DEFINE3(waitpid
, pid_t
, pid
, int __user
*, stat_addr
, int, options
)
1762 return sys_wait4(pid
, stat_addr
, options
, NULL
);