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/compat.h>
44 #include <linux/pipe_fs_i.h>
45 #include <linux/audit.h> /* for audit_free() */
46 #include <linux/resource.h>
47 #include <linux/blkdev.h>
48 #include <linux/task_io_accounting_ops.h>
49 #include <linux/tracehook.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>
57 static void exit_mm(struct task_struct
* tsk
);
59 static inline int task_detached(struct task_struct
*p
)
61 return p
->exit_signal
== -1;
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
->gtime
= cputime_add(sig
->gtime
, task_gtime(tsk
));
117 sig
->min_flt
+= tsk
->min_flt
;
118 sig
->maj_flt
+= tsk
->maj_flt
;
119 sig
->nvcsw
+= tsk
->nvcsw
;
120 sig
->nivcsw
+= tsk
->nivcsw
;
121 sig
->inblock
+= task_io_get_inblock(tsk
);
122 sig
->oublock
+= task_io_get_oublock(tsk
);
123 task_io_accounting_add(&sig
->ioac
, &tsk
->ioac
);
124 sig
= NULL
; /* Marker for below. */
127 __unhash_process(tsk
);
130 * Do this under ->siglock, we can race with another thread
131 * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
133 flush_sigqueue(&tsk
->pending
);
137 spin_unlock(&sighand
->siglock
);
139 __cleanup_sighand(sighand
);
140 clear_tsk_thread_flag(tsk
,TIF_SIGPENDING
);
142 flush_sigqueue(&sig
->shared_pending
);
143 taskstats_tgid_free(sig
);
145 * Make sure ->signal can't go away under rq->lock,
146 * see account_group_exec_runtime().
148 task_rq_unlock_wait(tsk
);
149 __cleanup_signal(sig
);
153 static void delayed_put_task_struct(struct rcu_head
*rhp
)
155 struct task_struct
*tsk
= container_of(rhp
, struct task_struct
, rcu
);
157 trace_sched_process_free(tsk
);
158 put_task_struct(tsk
);
162 void release_task(struct task_struct
* p
)
164 struct task_struct
*leader
;
167 tracehook_prepare_release_task(p
);
168 atomic_dec(&p
->user
->processes
);
170 write_lock_irq(&tasklist_lock
);
171 tracehook_finish_release_task(p
);
175 * If we are the last non-leader member of the thread
176 * group, and the leader is zombie, then notify the
177 * group leader's parent process. (if it wants notification.)
180 leader
= p
->group_leader
;
181 if (leader
!= p
&& thread_group_empty(leader
) && leader
->exit_state
== EXIT_ZOMBIE
) {
182 BUG_ON(task_detached(leader
));
183 do_notify_parent(leader
, leader
->exit_signal
);
185 * If we were the last child thread and the leader has
186 * exited already, and the leader's parent ignores SIGCHLD,
187 * then we are the one who should release the leader.
189 * do_notify_parent() will have marked it self-reaping in
192 zap_leader
= task_detached(leader
);
195 * This maintains the invariant that release_task()
196 * only runs on a task in EXIT_DEAD, just for sanity.
199 leader
->exit_state
= EXIT_DEAD
;
202 write_unlock_irq(&tasklist_lock
);
204 call_rcu(&p
->rcu
, delayed_put_task_struct
);
207 if (unlikely(zap_leader
))
212 * This checks not only the pgrp, but falls back on the pid if no
213 * satisfactory pgrp is found. I dunno - gdb doesn't work correctly
216 * The caller must hold rcu lock or the tasklist lock.
218 struct pid
*session_of_pgrp(struct pid
*pgrp
)
220 struct task_struct
*p
;
221 struct pid
*sid
= NULL
;
223 p
= pid_task(pgrp
, PIDTYPE_PGID
);
225 p
= pid_task(pgrp
, PIDTYPE_PID
);
227 sid
= task_session(p
);
233 * Determine if a process group is "orphaned", according to the POSIX
234 * definition in 2.2.2.52. Orphaned process groups are not to be affected
235 * by terminal-generated stop signals. Newly orphaned process groups are
236 * to receive a SIGHUP and a SIGCONT.
238 * "I ask you, have you ever known what it is to be an orphan?"
240 static int will_become_orphaned_pgrp(struct pid
*pgrp
, struct task_struct
*ignored_task
)
242 struct task_struct
*p
;
244 do_each_pid_task(pgrp
, PIDTYPE_PGID
, p
) {
245 if ((p
== ignored_task
) ||
246 (p
->exit_state
&& thread_group_empty(p
)) ||
247 is_global_init(p
->real_parent
))
250 if (task_pgrp(p
->real_parent
) != pgrp
&&
251 task_session(p
->real_parent
) == task_session(p
))
253 } while_each_pid_task(pgrp
, PIDTYPE_PGID
, p
);
258 int is_current_pgrp_orphaned(void)
262 read_lock(&tasklist_lock
);
263 retval
= will_become_orphaned_pgrp(task_pgrp(current
), NULL
);
264 read_unlock(&tasklist_lock
);
269 static int has_stopped_jobs(struct pid
*pgrp
)
272 struct task_struct
*p
;
274 do_each_pid_task(pgrp
, PIDTYPE_PGID
, p
) {
275 if (!task_is_stopped(p
))
279 } while_each_pid_task(pgrp
, PIDTYPE_PGID
, p
);
284 * Check to see if any process groups have become orphaned as
285 * a result of our exiting, and if they have any stopped jobs,
286 * send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
289 kill_orphaned_pgrp(struct task_struct
*tsk
, struct task_struct
*parent
)
291 struct pid
*pgrp
= task_pgrp(tsk
);
292 struct task_struct
*ignored_task
= tsk
;
295 /* exit: our father is in a different pgrp than
296 * we are and we were the only connection outside.
298 parent
= tsk
->real_parent
;
300 /* reparent: our child is in a different pgrp than
301 * we are, and it was the only connection outside.
305 if (task_pgrp(parent
) != pgrp
&&
306 task_session(parent
) == task_session(tsk
) &&
307 will_become_orphaned_pgrp(pgrp
, ignored_task
) &&
308 has_stopped_jobs(pgrp
)) {
309 __kill_pgrp_info(SIGHUP
, SEND_SIG_PRIV
, pgrp
);
310 __kill_pgrp_info(SIGCONT
, SEND_SIG_PRIV
, pgrp
);
315 * reparent_to_kthreadd - Reparent the calling kernel thread to kthreadd
317 * If a kernel thread is launched as a result of a system call, or if
318 * it ever exits, it should generally reparent itself to kthreadd so it
319 * isn't in the way of other processes and is correctly cleaned up on exit.
321 * The various task state such as scheduling policy and priority may have
322 * been inherited from a user process, so we reset them to sane values here.
324 * NOTE that reparent_to_kthreadd() gives the caller full capabilities.
326 static void reparent_to_kthreadd(void)
328 write_lock_irq(&tasklist_lock
);
330 ptrace_unlink(current
);
331 /* Reparent to init */
332 current
->real_parent
= current
->parent
= kthreadd_task
;
333 list_move_tail(¤t
->sibling
, ¤t
->real_parent
->children
);
335 /* Set the exit signal to SIGCHLD so we signal init on exit */
336 current
->exit_signal
= SIGCHLD
;
338 if (task_nice(current
) < 0)
339 set_user_nice(current
, 0);
343 security_task_reparent_to_init(current
);
344 memcpy(current
->signal
->rlim
, init_task
.signal
->rlim
,
345 sizeof(current
->signal
->rlim
));
346 atomic_inc(&(INIT_USER
->__count
));
347 write_unlock_irq(&tasklist_lock
);
348 switch_uid(INIT_USER
);
351 void __set_special_pids(struct pid
*pid
)
353 struct task_struct
*curr
= current
->group_leader
;
354 pid_t nr
= pid_nr(pid
);
356 if (task_session(curr
) != pid
) {
357 change_pid(curr
, PIDTYPE_SID
, pid
);
358 set_task_session(curr
, nr
);
360 if (task_pgrp(curr
) != pid
) {
361 change_pid(curr
, PIDTYPE_PGID
, pid
);
362 set_task_pgrp(curr
, nr
);
366 static void set_special_pids(struct pid
*pid
)
368 write_lock_irq(&tasklist_lock
);
369 __set_special_pids(pid
);
370 write_unlock_irq(&tasklist_lock
);
374 * Let kernel threads use this to say that they
375 * allow a certain signal (since daemonize() will
376 * have disabled all of them by default).
378 int allow_signal(int sig
)
380 if (!valid_signal(sig
) || sig
< 1)
383 spin_lock_irq(¤t
->sighand
->siglock
);
384 sigdelset(¤t
->blocked
, sig
);
386 /* Kernel threads handle their own signals.
387 Let the signal code know it'll be handled, so
388 that they don't get converted to SIGKILL or
389 just silently dropped */
390 current
->sighand
->action
[(sig
)-1].sa
.sa_handler
= (void __user
*)2;
393 spin_unlock_irq(¤t
->sighand
->siglock
);
397 EXPORT_SYMBOL(allow_signal
);
399 int disallow_signal(int sig
)
401 if (!valid_signal(sig
) || sig
< 1)
404 spin_lock_irq(¤t
->sighand
->siglock
);
405 current
->sighand
->action
[(sig
)-1].sa
.sa_handler
= SIG_IGN
;
407 spin_unlock_irq(¤t
->sighand
->siglock
);
411 EXPORT_SYMBOL(disallow_signal
);
414 * Put all the gunge required to become a kernel thread without
415 * attached user resources in one place where it belongs.
418 void daemonize(const char *name
, ...)
421 struct fs_struct
*fs
;
424 va_start(args
, name
);
425 vsnprintf(current
->comm
, sizeof(current
->comm
), name
, args
);
429 * If we were started as result of loading a module, close all of the
430 * user space pages. We don't need them, and if we didn't close them
431 * they would be locked into memory.
435 * We don't want to have TIF_FREEZE set if the system-wide hibernation
436 * or suspend transition begins right now.
438 current
->flags
|= (PF_NOFREEZE
| PF_KTHREAD
);
440 if (current
->nsproxy
!= &init_nsproxy
) {
441 get_nsproxy(&init_nsproxy
);
442 switch_task_namespaces(current
, &init_nsproxy
);
444 set_special_pids(&init_struct_pid
);
445 proc_clear_tty(current
);
447 /* Block and flush all signals */
448 sigfillset(&blocked
);
449 sigprocmask(SIG_BLOCK
, &blocked
, NULL
);
450 flush_signals(current
);
452 /* Become as one with the init task */
454 exit_fs(current
); /* current->fs->count--; */
457 atomic_inc(&fs
->count
);
460 current
->files
= init_task
.files
;
461 atomic_inc(¤t
->files
->count
);
463 reparent_to_kthreadd();
466 EXPORT_SYMBOL(daemonize
);
468 static void close_files(struct files_struct
* files
)
476 * It is safe to dereference the fd table without RCU or
477 * ->file_lock because this is the last reference to the
480 fdt
= files_fdtable(files
);
484 if (i
>= fdt
->max_fds
)
486 set
= fdt
->open_fds
->fds_bits
[j
++];
489 struct file
* file
= xchg(&fdt
->fd
[i
], NULL
);
491 filp_close(file
, files
);
501 struct files_struct
*get_files_struct(struct task_struct
*task
)
503 struct files_struct
*files
;
508 atomic_inc(&files
->count
);
514 void put_files_struct(struct files_struct
*files
)
518 if (atomic_dec_and_test(&files
->count
)) {
521 * Free the fd and fdset arrays if we expanded them.
522 * If the fdtable was embedded, pass files for freeing
523 * at the end of the RCU grace period. Otherwise,
524 * you can free files immediately.
526 fdt
= files_fdtable(files
);
527 if (fdt
!= &files
->fdtab
)
528 kmem_cache_free(files_cachep
, files
);
533 void reset_files_struct(struct files_struct
*files
)
535 struct task_struct
*tsk
= current
;
536 struct files_struct
*old
;
542 put_files_struct(old
);
545 void exit_files(struct task_struct
*tsk
)
547 struct files_struct
* files
= tsk
->files
;
553 put_files_struct(files
);
557 void put_fs_struct(struct fs_struct
*fs
)
559 /* No need to hold fs->lock if we are killing it */
560 if (atomic_dec_and_test(&fs
->count
)) {
563 kmem_cache_free(fs_cachep
, fs
);
567 void exit_fs(struct task_struct
*tsk
)
569 struct fs_struct
* fs
= tsk
->fs
;
579 EXPORT_SYMBOL_GPL(exit_fs
);
581 #ifdef CONFIG_MM_OWNER
583 * Task p is exiting and it owned mm, lets find a new owner for it
586 mm_need_new_owner(struct mm_struct
*mm
, struct task_struct
*p
)
589 * If there are other users of the mm and the owner (us) is exiting
590 * we need to find a new owner to take on the responsibility.
592 if (atomic_read(&mm
->mm_users
) <= 1)
599 void mm_update_next_owner(struct mm_struct
*mm
)
601 struct task_struct
*c
, *g
, *p
= current
;
604 if (!mm_need_new_owner(mm
, p
))
607 read_lock(&tasklist_lock
);
609 * Search in the children
611 list_for_each_entry(c
, &p
->children
, sibling
) {
613 goto assign_new_owner
;
617 * Search in the siblings
619 list_for_each_entry(c
, &p
->parent
->children
, sibling
) {
621 goto assign_new_owner
;
625 * Search through everything else. We should not get
628 do_each_thread(g
, c
) {
630 goto assign_new_owner
;
631 } while_each_thread(g
, c
);
633 read_unlock(&tasklist_lock
);
635 * We found no owner yet mm_users > 1: this implies that we are
636 * most likely racing with swapoff (try_to_unuse()) or /proc or
637 * ptrace or page migration (get_task_mm()). Mark owner as NULL,
638 * so that subsystems can understand the callback and take action.
640 down_write(&mm
->mmap_sem
);
641 cgroup_mm_owner_callbacks(mm
->owner
, NULL
);
643 up_write(&mm
->mmap_sem
);
649 read_unlock(&tasklist_lock
);
650 down_write(&mm
->mmap_sem
);
652 * The task_lock protects c->mm from changing.
653 * We always want mm->owner->mm == mm
658 up_write(&mm
->mmap_sem
);
662 cgroup_mm_owner_callbacks(mm
->owner
, c
);
665 up_write(&mm
->mmap_sem
);
668 #endif /* CONFIG_MM_OWNER */
671 * Turn us into a lazy TLB process if we
674 static void exit_mm(struct task_struct
* tsk
)
676 struct mm_struct
*mm
= tsk
->mm
;
677 struct core_state
*core_state
;
683 * Serialize with any possible pending coredump.
684 * We must hold mmap_sem around checking core_state
685 * and clearing tsk->mm. The core-inducing thread
686 * will increment ->nr_threads for each thread in the
687 * group with ->mm != NULL.
689 down_read(&mm
->mmap_sem
);
690 core_state
= mm
->core_state
;
692 struct core_thread self
;
693 up_read(&mm
->mmap_sem
);
696 self
.next
= xchg(&core_state
->dumper
.next
, &self
);
698 * Implies mb(), the result of xchg() must be visible
699 * to core_state->dumper.
701 if (atomic_dec_and_test(&core_state
->nr_threads
))
702 complete(&core_state
->startup
);
705 set_task_state(tsk
, TASK_UNINTERRUPTIBLE
);
706 if (!self
.task
) /* see coredump_finish() */
710 __set_task_state(tsk
, TASK_RUNNING
);
711 down_read(&mm
->mmap_sem
);
713 atomic_inc(&mm
->mm_count
);
714 BUG_ON(mm
!= tsk
->active_mm
);
715 /* more a memory barrier than a real lock */
718 up_read(&mm
->mmap_sem
);
719 enter_lazy_tlb(mm
, current
);
720 /* We don't want this task to be frozen prematurely */
721 clear_freeze_flag(tsk
);
723 mm_update_next_owner(mm
);
728 * Return nonzero if @parent's children should reap themselves.
730 * Called with write_lock_irq(&tasklist_lock) held.
732 static int ignoring_children(struct task_struct
*parent
)
735 struct sighand_struct
*psig
= parent
->sighand
;
737 spin_lock_irqsave(&psig
->siglock
, flags
);
738 ret
= (psig
->action
[SIGCHLD
-1].sa
.sa_handler
== SIG_IGN
||
739 (psig
->action
[SIGCHLD
-1].sa
.sa_flags
& SA_NOCLDWAIT
));
740 spin_unlock_irqrestore(&psig
->siglock
, flags
);
745 * Detach all tasks we were using ptrace on.
746 * Any that need to be release_task'd are put on the @dead list.
748 * Called with write_lock(&tasklist_lock) held.
750 static void ptrace_exit(struct task_struct
*parent
, struct list_head
*dead
)
752 struct task_struct
*p
, *n
;
755 list_for_each_entry_safe(p
, n
, &parent
->ptraced
, ptrace_entry
) {
758 if (p
->exit_state
!= EXIT_ZOMBIE
)
762 * If it's a zombie, our attachedness prevented normal
763 * parent notification or self-reaping. Do notification
764 * now if it would have happened earlier. If it should
765 * reap itself, add it to the @dead list. We can't call
766 * release_task() here because we already hold tasklist_lock.
768 * If it's our own child, there is no notification to do.
769 * But if our normal children self-reap, then this child
770 * was prevented by ptrace and we must reap it now.
772 if (!task_detached(p
) && thread_group_empty(p
)) {
773 if (!same_thread_group(p
->real_parent
, parent
))
774 do_notify_parent(p
, p
->exit_signal
);
777 ign
= ignoring_children(parent
);
783 if (task_detached(p
)) {
785 * Mark it as in the process of being reaped.
787 p
->exit_state
= EXIT_DEAD
;
788 list_add(&p
->ptrace_entry
, dead
);
794 * Finish up exit-time ptrace cleanup.
796 * Called without locks.
798 static void ptrace_exit_finish(struct task_struct
*parent
,
799 struct list_head
*dead
)
801 struct task_struct
*p
, *n
;
803 BUG_ON(!list_empty(&parent
->ptraced
));
805 list_for_each_entry_safe(p
, n
, dead
, ptrace_entry
) {
806 list_del_init(&p
->ptrace_entry
);
811 static void reparent_thread(struct task_struct
*p
, struct task_struct
*father
)
813 if (p
->pdeath_signal
)
814 /* We already hold the tasklist_lock here. */
815 group_send_sig_info(p
->pdeath_signal
, SEND_SIG_NOINFO
, p
);
817 list_move_tail(&p
->sibling
, &p
->real_parent
->children
);
819 /* If this is a threaded reparent there is no need to
820 * notify anyone anything has happened.
822 if (same_thread_group(p
->real_parent
, father
))
825 /* We don't want people slaying init. */
826 if (!task_detached(p
))
827 p
->exit_signal
= SIGCHLD
;
829 /* If we'd notified the old parent about this child's death,
830 * also notify the new parent.
832 if (!ptrace_reparented(p
) &&
833 p
->exit_state
== EXIT_ZOMBIE
&&
834 !task_detached(p
) && thread_group_empty(p
))
835 do_notify_parent(p
, p
->exit_signal
);
837 kill_orphaned_pgrp(p
, father
);
841 * When we die, we re-parent all our children.
842 * Try to give them to another thread in our thread
843 * group, and if no such member exists, give it to
844 * the child reaper process (ie "init") in our pid
847 static struct task_struct
*find_new_reaper(struct task_struct
*father
)
849 struct pid_namespace
*pid_ns
= task_active_pid_ns(father
);
850 struct task_struct
*thread
;
853 while_each_thread(father
, thread
) {
854 if (thread
->flags
& PF_EXITING
)
856 if (unlikely(pid_ns
->child_reaper
== father
))
857 pid_ns
->child_reaper
= thread
;
861 if (unlikely(pid_ns
->child_reaper
== father
)) {
862 write_unlock_irq(&tasklist_lock
);
863 if (unlikely(pid_ns
== &init_pid_ns
))
864 panic("Attempted to kill init!");
866 zap_pid_ns_processes(pid_ns
);
867 write_lock_irq(&tasklist_lock
);
869 * We can not clear ->child_reaper or leave it alone.
870 * There may by stealth EXIT_DEAD tasks on ->children,
871 * forget_original_parent() must move them somewhere.
873 pid_ns
->child_reaper
= init_pid_ns
.child_reaper
;
876 return pid_ns
->child_reaper
;
879 static void forget_original_parent(struct task_struct
*father
)
881 struct task_struct
*p
, *n
, *reaper
;
882 LIST_HEAD(ptrace_dead
);
884 write_lock_irq(&tasklist_lock
);
885 reaper
= find_new_reaper(father
);
887 * First clean up ptrace if we were using it.
889 ptrace_exit(father
, &ptrace_dead
);
891 list_for_each_entry_safe(p
, n
, &father
->children
, sibling
) {
892 p
->real_parent
= reaper
;
893 if (p
->parent
== father
) {
895 p
->parent
= p
->real_parent
;
897 reparent_thread(p
, father
);
900 write_unlock_irq(&tasklist_lock
);
901 BUG_ON(!list_empty(&father
->children
));
903 ptrace_exit_finish(father
, &ptrace_dead
);
907 * Send signals to all our closest relatives so that they know
908 * to properly mourn us..
910 static void exit_notify(struct task_struct
*tsk
, int group_dead
)
916 * This does two things:
918 * A. Make init inherit all the child processes
919 * B. Check to see if any process groups have become orphaned
920 * as a result of our exiting, and if they have any stopped
921 * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
923 forget_original_parent(tsk
);
924 exit_task_namespaces(tsk
);
926 write_lock_irq(&tasklist_lock
);
928 kill_orphaned_pgrp(tsk
->group_leader
, NULL
);
930 /* Let father know we died
932 * Thread signals are configurable, but you aren't going to use
933 * that to send signals to arbitary processes.
934 * That stops right now.
936 * If the parent exec id doesn't match the exec id we saved
937 * when we started then we know the parent has changed security
940 * If our self_exec id doesn't match our parent_exec_id then
941 * we have changed execution domain as these two values started
942 * the same after a fork.
944 if (tsk
->exit_signal
!= SIGCHLD
&& !task_detached(tsk
) &&
945 (tsk
->parent_exec_id
!= tsk
->real_parent
->self_exec_id
||
946 tsk
->self_exec_id
!= tsk
->parent_exec_id
) &&
948 tsk
->exit_signal
= SIGCHLD
;
950 signal
= tracehook_notify_death(tsk
, &cookie
, group_dead
);
952 signal
= do_notify_parent(tsk
, signal
);
954 tsk
->exit_state
= signal
== DEATH_REAP
? EXIT_DEAD
: EXIT_ZOMBIE
;
956 /* mt-exec, de_thread() is waiting for us */
957 if (thread_group_leader(tsk
) &&
958 tsk
->signal
->group_exit_task
&&
959 tsk
->signal
->notify_count
< 0)
960 wake_up_process(tsk
->signal
->group_exit_task
);
962 write_unlock_irq(&tasklist_lock
);
964 tracehook_report_death(tsk
, signal
, cookie
, group_dead
);
966 /* If the process is dead, release it - nobody will wait for it */
967 if (signal
== DEATH_REAP
)
971 #ifdef CONFIG_DEBUG_STACK_USAGE
972 static void check_stack_usage(void)
974 static DEFINE_SPINLOCK(low_water_lock
);
975 static int lowest_to_date
= THREAD_SIZE
;
976 unsigned long *n
= end_of_stack(current
);
981 free
= (unsigned long)n
- (unsigned long)end_of_stack(current
);
983 if (free
>= lowest_to_date
)
986 spin_lock(&low_water_lock
);
987 if (free
< lowest_to_date
) {
988 printk(KERN_WARNING
"%s used greatest stack depth: %lu bytes "
990 current
->comm
, free
);
991 lowest_to_date
= free
;
993 spin_unlock(&low_water_lock
);
996 static inline void check_stack_usage(void) {}
999 NORET_TYPE
void do_exit(long code
)
1001 struct task_struct
*tsk
= current
;
1004 profile_task_exit(tsk
);
1006 WARN_ON(atomic_read(&tsk
->fs_excl
));
1008 if (unlikely(in_interrupt()))
1009 panic("Aiee, killing interrupt handler!");
1010 if (unlikely(!tsk
->pid
))
1011 panic("Attempted to kill the idle task!");
1013 tracehook_report_exit(&code
);
1016 * We're taking recursive faults here in do_exit. Safest is to just
1017 * leave this task alone and wait for reboot.
1019 if (unlikely(tsk
->flags
& PF_EXITING
)) {
1021 "Fixing recursive fault but reboot is needed!\n");
1023 * We can do this unlocked here. The futex code uses
1024 * this flag just to verify whether the pi state
1025 * cleanup has been done or not. In the worst case it
1026 * loops once more. We pretend that the cleanup was
1027 * done as there is no way to return. Either the
1028 * OWNER_DIED bit is set by now or we push the blocked
1029 * task into the wait for ever nirwana as well.
1031 tsk
->flags
|= PF_EXITPIDONE
;
1032 if (tsk
->io_context
)
1034 set_current_state(TASK_UNINTERRUPTIBLE
);
1038 exit_signals(tsk
); /* sets PF_EXITING */
1040 * tsk->flags are checked in the futex code to protect against
1041 * an exiting task cleaning up the robust pi futexes.
1044 spin_unlock_wait(&tsk
->pi_lock
);
1046 if (unlikely(in_atomic()))
1047 printk(KERN_INFO
"note: %s[%d] exited with preempt_count %d\n",
1048 current
->comm
, task_pid_nr(current
),
1051 acct_update_integrals(tsk
);
1053 update_hiwater_rss(tsk
->mm
);
1054 update_hiwater_vm(tsk
->mm
);
1056 group_dead
= atomic_dec_and_test(&tsk
->signal
->live
);
1058 hrtimer_cancel(&tsk
->signal
->real_timer
);
1059 exit_itimers(tsk
->signal
);
1061 acct_collect(code
, group_dead
);
1063 if (unlikely(tsk
->robust_list
))
1064 exit_robust_list(tsk
);
1065 #ifdef CONFIG_COMPAT
1066 if (unlikely(tsk
->compat_robust_list
))
1067 compat_exit_robust_list(tsk
);
1072 if (unlikely(tsk
->audit_context
))
1075 tsk
->exit_code
= code
;
1076 taskstats_exit(tsk
, group_dead
);
1082 trace_sched_process_exit(tsk
);
1087 check_stack_usage();
1089 cgroup_exit(tsk
, 1);
1092 if (group_dead
&& tsk
->signal
->leader
)
1093 disassociate_ctty(1);
1095 module_put(task_thread_info(tsk
)->exec_domain
->module
);
1097 module_put(tsk
->binfmt
->module
);
1099 proc_exit_connector(tsk
);
1100 exit_notify(tsk
, group_dead
);
1102 mpol_put(tsk
->mempolicy
);
1103 tsk
->mempolicy
= NULL
;
1107 * This must happen late, after the PID is not
1110 if (unlikely(!list_empty(&tsk
->pi_state_list
)))
1111 exit_pi_state_list(tsk
);
1112 if (unlikely(current
->pi_state_cache
))
1113 kfree(current
->pi_state_cache
);
1116 * Make sure we are holding no locks:
1118 debug_check_no_locks_held(tsk
);
1120 * We can do this unlocked here. The futex code uses this flag
1121 * just to verify whether the pi state cleanup has been done
1122 * or not. In the worst case it loops once more.
1124 tsk
->flags
|= PF_EXITPIDONE
;
1126 if (tsk
->io_context
)
1129 if (tsk
->splice_pipe
)
1130 __free_pipe_info(tsk
->splice_pipe
);
1133 /* causes final put_task_struct in finish_task_switch(). */
1134 tsk
->state
= TASK_DEAD
;
1138 /* Avoid "noreturn function does return". */
1140 cpu_relax(); /* For when BUG is null */
1143 EXPORT_SYMBOL_GPL(do_exit
);
1145 NORET_TYPE
void complete_and_exit(struct completion
*comp
, long code
)
1153 EXPORT_SYMBOL(complete_and_exit
);
1155 asmlinkage
long sys_exit(int error_code
)
1157 do_exit((error_code
&0xff)<<8);
1161 * Take down every thread in the group. This is called by fatal signals
1162 * as well as by sys_exit_group (below).
1165 do_group_exit(int exit_code
)
1167 struct signal_struct
*sig
= current
->signal
;
1169 BUG_ON(exit_code
& 0x80); /* core dumps don't get here */
1171 if (signal_group_exit(sig
))
1172 exit_code
= sig
->group_exit_code
;
1173 else if (!thread_group_empty(current
)) {
1174 struct sighand_struct
*const sighand
= current
->sighand
;
1175 spin_lock_irq(&sighand
->siglock
);
1176 if (signal_group_exit(sig
))
1177 /* Another thread got here before we took the lock. */
1178 exit_code
= sig
->group_exit_code
;
1180 sig
->group_exit_code
= exit_code
;
1181 sig
->flags
= SIGNAL_GROUP_EXIT
;
1182 zap_other_threads(current
);
1184 spin_unlock_irq(&sighand
->siglock
);
1192 * this kills every thread in the thread group. Note that any externally
1193 * wait4()-ing process will get the correct exit code - even if this
1194 * thread is not the thread group leader.
1196 asmlinkage
void sys_exit_group(int error_code
)
1198 do_group_exit((error_code
& 0xff) << 8);
1201 static struct pid
*task_pid_type(struct task_struct
*task
, enum pid_type type
)
1203 struct pid
*pid
= NULL
;
1204 if (type
== PIDTYPE_PID
)
1205 pid
= task
->pids
[type
].pid
;
1206 else if (type
< PIDTYPE_MAX
)
1207 pid
= task
->group_leader
->pids
[type
].pid
;
1211 static int eligible_child(enum pid_type type
, struct pid
*pid
, int options
,
1212 struct task_struct
*p
)
1216 if (type
< PIDTYPE_MAX
) {
1217 if (task_pid_type(p
, type
) != pid
)
1221 /* Wait for all children (clone and not) if __WALL is set;
1222 * otherwise, wait for clone children *only* if __WCLONE is
1223 * set; otherwise, wait for non-clone children *only*. (Note:
1224 * A "clone" child here is one that reports to its parent
1225 * using a signal other than SIGCHLD.) */
1226 if (((p
->exit_signal
!= SIGCHLD
) ^ ((options
& __WCLONE
) != 0))
1227 && !(options
& __WALL
))
1230 err
= security_task_wait(p
);
1237 static int wait_noreap_copyout(struct task_struct
*p
, pid_t pid
, uid_t uid
,
1238 int why
, int status
,
1239 struct siginfo __user
*infop
,
1240 struct rusage __user
*rusagep
)
1242 int retval
= rusagep
? getrusage(p
, RUSAGE_BOTH
, rusagep
) : 0;
1246 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1248 retval
= put_user(0, &infop
->si_errno
);
1250 retval
= put_user((short)why
, &infop
->si_code
);
1252 retval
= put_user(pid
, &infop
->si_pid
);
1254 retval
= put_user(uid
, &infop
->si_uid
);
1256 retval
= put_user(status
, &infop
->si_status
);
1263 * Handle sys_wait4 work for one task in state EXIT_ZOMBIE. We hold
1264 * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
1265 * the lock and this task is uninteresting. If we return nonzero, we have
1266 * released the lock and the system call should return.
1268 static int wait_task_zombie(struct task_struct
*p
, int options
,
1269 struct siginfo __user
*infop
,
1270 int __user
*stat_addr
, struct rusage __user
*ru
)
1272 unsigned long state
;
1273 int retval
, status
, traced
;
1274 pid_t pid
= task_pid_vnr(p
);
1276 if (!likely(options
& WEXITED
))
1279 if (unlikely(options
& WNOWAIT
)) {
1281 int exit_code
= p
->exit_code
;
1285 read_unlock(&tasklist_lock
);
1286 if ((exit_code
& 0x7f) == 0) {
1288 status
= exit_code
>> 8;
1290 why
= (exit_code
& 0x80) ? CLD_DUMPED
: CLD_KILLED
;
1291 status
= exit_code
& 0x7f;
1293 return wait_noreap_copyout(p
, pid
, uid
, why
,
1298 * Try to move the task's state to DEAD
1299 * only one thread is allowed to do this:
1301 state
= xchg(&p
->exit_state
, EXIT_DEAD
);
1302 if (state
!= EXIT_ZOMBIE
) {
1303 BUG_ON(state
!= EXIT_DEAD
);
1307 traced
= ptrace_reparented(p
);
1309 if (likely(!traced
)) {
1310 struct signal_struct
*psig
;
1311 struct signal_struct
*sig
;
1312 struct task_cputime cputime
;
1315 * The resource counters for the group leader are in its
1316 * own task_struct. Those for dead threads in the group
1317 * are in its signal_struct, as are those for the child
1318 * processes it has previously reaped. All these
1319 * accumulate in the parent's signal_struct c* fields.
1321 * We don't bother to take a lock here to protect these
1322 * p->signal fields, because they are only touched by
1323 * __exit_signal, which runs with tasklist_lock
1324 * write-locked anyway, and so is excluded here. We do
1325 * need to protect the access to p->parent->signal fields,
1326 * as other threads in the parent group can be right
1327 * here reaping other children at the same time.
1329 * We use thread_group_cputime() to get times for the thread
1330 * group, which consolidates times for all threads in the
1331 * group including the group leader.
1333 spin_lock_irq(&p
->parent
->sighand
->siglock
);
1334 psig
= p
->parent
->signal
;
1336 thread_group_cputime(p
, &cputime
);
1338 cputime_add(psig
->cutime
,
1339 cputime_add(cputime
.utime
,
1342 cputime_add(psig
->cstime
,
1343 cputime_add(cputime
.stime
,
1346 cputime_add(psig
->cgtime
,
1347 cputime_add(p
->gtime
,
1348 cputime_add(sig
->gtime
,
1351 p
->min_flt
+ sig
->min_flt
+ sig
->cmin_flt
;
1353 p
->maj_flt
+ sig
->maj_flt
+ sig
->cmaj_flt
;
1355 p
->nvcsw
+ sig
->nvcsw
+ sig
->cnvcsw
;
1357 p
->nivcsw
+ sig
->nivcsw
+ sig
->cnivcsw
;
1359 task_io_get_inblock(p
) +
1360 sig
->inblock
+ sig
->cinblock
;
1362 task_io_get_oublock(p
) +
1363 sig
->oublock
+ sig
->coublock
;
1364 task_io_accounting_add(&psig
->ioac
, &p
->ioac
);
1365 task_io_accounting_add(&psig
->ioac
, &sig
->ioac
);
1366 spin_unlock_irq(&p
->parent
->sighand
->siglock
);
1370 * Now we are sure this task is interesting, and no other
1371 * thread can reap it because we set its state to EXIT_DEAD.
1373 read_unlock(&tasklist_lock
);
1375 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1376 status
= (p
->signal
->flags
& SIGNAL_GROUP_EXIT
)
1377 ? p
->signal
->group_exit_code
: p
->exit_code
;
1378 if (!retval
&& stat_addr
)
1379 retval
= put_user(status
, stat_addr
);
1380 if (!retval
&& infop
)
1381 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1382 if (!retval
&& infop
)
1383 retval
= put_user(0, &infop
->si_errno
);
1384 if (!retval
&& infop
) {
1387 if ((status
& 0x7f) == 0) {
1391 why
= (status
& 0x80) ? CLD_DUMPED
: CLD_KILLED
;
1394 retval
= put_user((short)why
, &infop
->si_code
);
1396 retval
= put_user(status
, &infop
->si_status
);
1398 if (!retval
&& infop
)
1399 retval
= put_user(pid
, &infop
->si_pid
);
1400 if (!retval
&& infop
)
1401 retval
= put_user(p
->uid
, &infop
->si_uid
);
1406 write_lock_irq(&tasklist_lock
);
1407 /* We dropped tasklist, ptracer could die and untrace */
1410 * If this is not a detached task, notify the parent.
1411 * If it's still not detached after that, don't release
1414 if (!task_detached(p
)) {
1415 do_notify_parent(p
, p
->exit_signal
);
1416 if (!task_detached(p
)) {
1417 p
->exit_state
= EXIT_ZOMBIE
;
1421 write_unlock_irq(&tasklist_lock
);
1430 * Handle sys_wait4 work for one task in state TASK_STOPPED. We hold
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_stopped(int ptrace
, struct task_struct
*p
,
1436 int options
, struct siginfo __user
*infop
,
1437 int __user
*stat_addr
, struct rusage __user
*ru
)
1439 int retval
, exit_code
, why
;
1440 uid_t uid
= 0; /* unneeded, required by compiler */
1443 if (!(options
& WUNTRACED
))
1447 spin_lock_irq(&p
->sighand
->siglock
);
1449 if (unlikely(!task_is_stopped_or_traced(p
)))
1452 if (!ptrace
&& p
->signal
->group_stop_count
> 0)
1454 * A group stop is in progress and this is the group leader.
1455 * We won't report until all threads have stopped.
1459 exit_code
= p
->exit_code
;
1463 if (!unlikely(options
& WNOWAIT
))
1468 spin_unlock_irq(&p
->sighand
->siglock
);
1473 * Now we are pretty sure this task is interesting.
1474 * Make sure it doesn't get reaped out from under us while we
1475 * give up the lock and then examine it below. We don't want to
1476 * keep holding onto the tasklist_lock while we call getrusage and
1477 * possibly take page faults for user memory.
1480 pid
= task_pid_vnr(p
);
1481 why
= ptrace
? CLD_TRAPPED
: CLD_STOPPED
;
1482 read_unlock(&tasklist_lock
);
1484 if (unlikely(options
& WNOWAIT
))
1485 return wait_noreap_copyout(p
, pid
, uid
,
1489 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1490 if (!retval
&& stat_addr
)
1491 retval
= put_user((exit_code
<< 8) | 0x7f, stat_addr
);
1492 if (!retval
&& infop
)
1493 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1494 if (!retval
&& infop
)
1495 retval
= put_user(0, &infop
->si_errno
);
1496 if (!retval
&& infop
)
1497 retval
= put_user((short)why
, &infop
->si_code
);
1498 if (!retval
&& infop
)
1499 retval
= put_user(exit_code
, &infop
->si_status
);
1500 if (!retval
&& infop
)
1501 retval
= put_user(pid
, &infop
->si_pid
);
1502 if (!retval
&& infop
)
1503 retval
= put_user(uid
, &infop
->si_uid
);
1513 * Handle do_wait work for one task in a live, non-stopped state.
1514 * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
1515 * the lock and this task is uninteresting. If we return nonzero, we have
1516 * released the lock and the system call should return.
1518 static int wait_task_continued(struct task_struct
*p
, int options
,
1519 struct siginfo __user
*infop
,
1520 int __user
*stat_addr
, struct rusage __user
*ru
)
1526 if (!unlikely(options
& WCONTINUED
))
1529 if (!(p
->signal
->flags
& SIGNAL_STOP_CONTINUED
))
1532 spin_lock_irq(&p
->sighand
->siglock
);
1533 /* Re-check with the lock held. */
1534 if (!(p
->signal
->flags
& SIGNAL_STOP_CONTINUED
)) {
1535 spin_unlock_irq(&p
->sighand
->siglock
);
1538 if (!unlikely(options
& WNOWAIT
))
1539 p
->signal
->flags
&= ~SIGNAL_STOP_CONTINUED
;
1540 spin_unlock_irq(&p
->sighand
->siglock
);
1542 pid
= task_pid_vnr(p
);
1545 read_unlock(&tasklist_lock
);
1548 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1550 if (!retval
&& stat_addr
)
1551 retval
= put_user(0xffff, stat_addr
);
1555 retval
= wait_noreap_copyout(p
, pid
, uid
,
1556 CLD_CONTINUED
, SIGCONT
,
1558 BUG_ON(retval
== 0);
1565 * Consider @p for a wait by @parent.
1567 * -ECHILD should be in *@notask_error before the first call.
1568 * Returns nonzero for a final return, when we have unlocked tasklist_lock.
1569 * Returns zero if the search for a child should continue;
1570 * then *@notask_error is 0 if @p is an eligible child,
1571 * or another error from security_task_wait(), or still -ECHILD.
1573 static int wait_consider_task(struct task_struct
*parent
, int ptrace
,
1574 struct task_struct
*p
, int *notask_error
,
1575 enum pid_type type
, struct pid
*pid
, int options
,
1576 struct siginfo __user
*infop
,
1577 int __user
*stat_addr
, struct rusage __user
*ru
)
1579 int ret
= eligible_child(type
, pid
, options
, p
);
1583 if (unlikely(ret
< 0)) {
1585 * If we have not yet seen any eligible child,
1586 * then let this error code replace -ECHILD.
1587 * A permission error will give the user a clue
1588 * to look for security policy problems, rather
1589 * than for mysterious wait bugs.
1592 *notask_error
= ret
;
1595 if (likely(!ptrace
) && unlikely(p
->ptrace
)) {
1597 * This child is hidden by ptrace.
1598 * We aren't allowed to see it now, but eventually we will.
1604 if (p
->exit_state
== EXIT_DEAD
)
1608 * We don't reap group leaders with subthreads.
1610 if (p
->exit_state
== EXIT_ZOMBIE
&& !delay_group_leader(p
))
1611 return wait_task_zombie(p
, options
, infop
, stat_addr
, ru
);
1614 * It's stopped or running now, so it might
1615 * later continue, exit, or stop again.
1619 if (task_is_stopped_or_traced(p
))
1620 return wait_task_stopped(ptrace
, p
, options
,
1621 infop
, stat_addr
, ru
);
1623 return wait_task_continued(p
, options
, infop
, stat_addr
, ru
);
1627 * Do the work of do_wait() for one thread in the group, @tsk.
1629 * -ECHILD should be in *@notask_error before the first call.
1630 * Returns nonzero for a final return, when we have unlocked tasklist_lock.
1631 * Returns zero if the search for a child should continue; then
1632 * *@notask_error is 0 if there were any eligible children,
1633 * or another error from security_task_wait(), or still -ECHILD.
1635 static int do_wait_thread(struct task_struct
*tsk
, int *notask_error
,
1636 enum pid_type type
, struct pid
*pid
, int options
,
1637 struct siginfo __user
*infop
, int __user
*stat_addr
,
1638 struct rusage __user
*ru
)
1640 struct task_struct
*p
;
1642 list_for_each_entry(p
, &tsk
->children
, sibling
) {
1644 * Do not consider detached threads.
1646 if (!task_detached(p
)) {
1647 int ret
= wait_consider_task(tsk
, 0, p
, notask_error
,
1649 infop
, stat_addr
, ru
);
1658 static int ptrace_do_wait(struct task_struct
*tsk
, int *notask_error
,
1659 enum pid_type type
, struct pid
*pid
, int options
,
1660 struct siginfo __user
*infop
, int __user
*stat_addr
,
1661 struct rusage __user
*ru
)
1663 struct task_struct
*p
;
1666 * Traditionally we see ptrace'd stopped tasks regardless of options.
1668 options
|= WUNTRACED
;
1670 list_for_each_entry(p
, &tsk
->ptraced
, ptrace_entry
) {
1671 int ret
= wait_consider_task(tsk
, 1, p
, notask_error
,
1673 infop
, stat_addr
, ru
);
1681 static long do_wait(enum pid_type type
, struct pid
*pid
, int options
,
1682 struct siginfo __user
*infop
, int __user
*stat_addr
,
1683 struct rusage __user
*ru
)
1685 DECLARE_WAITQUEUE(wait
, current
);
1686 struct task_struct
*tsk
;
1689 trace_sched_process_wait(pid
);
1691 add_wait_queue(¤t
->signal
->wait_chldexit
,&wait
);
1694 * If there is nothing that can match our critiera just get out.
1695 * We will clear @retval to zero if we see any child that might later
1696 * match our criteria, even if we are not able to reap it yet.
1699 if ((type
< PIDTYPE_MAX
) && (!pid
|| hlist_empty(&pid
->tasks
[type
])))
1702 current
->state
= TASK_INTERRUPTIBLE
;
1703 read_lock(&tasklist_lock
);
1706 int tsk_result
= do_wait_thread(tsk
, &retval
,
1708 infop
, stat_addr
, ru
);
1710 tsk_result
= ptrace_do_wait(tsk
, &retval
,
1712 infop
, stat_addr
, ru
);
1715 * tasklist_lock is unlocked and we have a final result.
1717 retval
= tsk_result
;
1721 if (options
& __WNOTHREAD
)
1723 tsk
= next_thread(tsk
);
1724 BUG_ON(tsk
->signal
!= current
->signal
);
1725 } while (tsk
!= current
);
1726 read_unlock(&tasklist_lock
);
1728 if (!retval
&& !(options
& WNOHANG
)) {
1729 retval
= -ERESTARTSYS
;
1730 if (!signal_pending(current
)) {
1737 current
->state
= TASK_RUNNING
;
1738 remove_wait_queue(¤t
->signal
->wait_chldexit
,&wait
);
1744 * For a WNOHANG return, clear out all the fields
1745 * we would set so the user can easily tell the
1749 retval
= put_user(0, &infop
->si_signo
);
1751 retval
= put_user(0, &infop
->si_errno
);
1753 retval
= put_user(0, &infop
->si_code
);
1755 retval
= put_user(0, &infop
->si_pid
);
1757 retval
= put_user(0, &infop
->si_uid
);
1759 retval
= put_user(0, &infop
->si_status
);
1765 asmlinkage
long sys_waitid(int which
, pid_t upid
,
1766 struct siginfo __user
*infop
, int options
,
1767 struct rusage __user
*ru
)
1769 struct pid
*pid
= NULL
;
1773 if (options
& ~(WNOHANG
|WNOWAIT
|WEXITED
|WSTOPPED
|WCONTINUED
))
1775 if (!(options
& (WEXITED
|WSTOPPED
|WCONTINUED
)))
1788 type
= PIDTYPE_PGID
;
1796 if (type
< PIDTYPE_MAX
)
1797 pid
= find_get_pid(upid
);
1798 ret
= do_wait(type
, pid
, options
, infop
, NULL
, ru
);
1801 /* avoid REGPARM breakage on x86: */
1802 asmlinkage_protect(5, ret
, which
, upid
, infop
, options
, ru
);
1806 asmlinkage
long sys_wait4(pid_t upid
, int __user
*stat_addr
,
1807 int options
, struct rusage __user
*ru
)
1809 struct pid
*pid
= NULL
;
1813 if (options
& ~(WNOHANG
|WUNTRACED
|WCONTINUED
|
1814 __WNOTHREAD
|__WCLONE
|__WALL
))
1819 else if (upid
< 0) {
1820 type
= PIDTYPE_PGID
;
1821 pid
= find_get_pid(-upid
);
1822 } else if (upid
== 0) {
1823 type
= PIDTYPE_PGID
;
1824 pid
= get_pid(task_pgrp(current
));
1825 } else /* upid > 0 */ {
1827 pid
= find_get_pid(upid
);
1830 ret
= do_wait(type
, pid
, options
| WEXITED
, NULL
, stat_addr
, ru
);
1833 /* avoid REGPARM breakage on x86: */
1834 asmlinkage_protect(4, ret
, upid
, stat_addr
, options
, ru
);
1838 #ifdef __ARCH_WANT_SYS_WAITPID
1841 * sys_waitpid() remains for compatibility. waitpid() should be
1842 * implemented by calling sys_wait4() from libc.a.
1844 asmlinkage
long sys_waitpid(pid_t pid
, int __user
*stat_addr
, int options
)
1846 return sys_wait4(pid
, stat_addr
, options
, NULL
);
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