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 static void exit_mm(struct task_struct
* tsk
);
60 static inline int task_detached(struct task_struct
*p
)
62 return p
->exit_signal
== -1;
65 static void __unhash_process(struct task_struct
*p
)
68 detach_pid(p
, PIDTYPE_PID
);
69 if (thread_group_leader(p
)) {
70 detach_pid(p
, PIDTYPE_PGID
);
71 detach_pid(p
, PIDTYPE_SID
);
73 list_del_rcu(&p
->tasks
);
74 __get_cpu_var(process_counts
)--;
76 list_del_rcu(&p
->thread_group
);
77 list_del_init(&p
->sibling
);
81 * This function expects the tasklist_lock write-locked.
83 static void __exit_signal(struct task_struct
*tsk
)
85 struct signal_struct
*sig
= tsk
->signal
;
86 struct sighand_struct
*sighand
;
89 BUG_ON(!atomic_read(&sig
->count
));
91 sighand
= rcu_dereference(tsk
->sighand
);
92 spin_lock(&sighand
->siglock
);
94 posix_cpu_timers_exit(tsk
);
95 if (atomic_dec_and_test(&sig
->count
))
96 posix_cpu_timers_exit_group(tsk
);
99 * If there is any task waiting for the group exit
102 if (sig
->group_exit_task
&& atomic_read(&sig
->count
) == sig
->notify_count
)
103 wake_up_process(sig
->group_exit_task
);
105 if (tsk
== sig
->curr_target
)
106 sig
->curr_target
= next_thread(tsk
);
108 * Accumulate here the counters for all threads but the
109 * group leader as they die, so they can be added into
110 * the process-wide totals when those are taken.
111 * The group leader stays around as a zombie as long
112 * as there are other threads. When it gets reaped,
113 * the exit.c code will add its counts into these totals.
114 * We won't ever get here for the group leader, since it
115 * will have been the last reference on the signal_struct.
117 sig
->gtime
= cputime_add(sig
->gtime
, task_gtime(tsk
));
118 sig
->min_flt
+= tsk
->min_flt
;
119 sig
->maj_flt
+= tsk
->maj_flt
;
120 sig
->nvcsw
+= tsk
->nvcsw
;
121 sig
->nivcsw
+= tsk
->nivcsw
;
122 sig
->inblock
+= task_io_get_inblock(tsk
);
123 sig
->oublock
+= task_io_get_oublock(tsk
);
124 task_io_accounting_add(&sig
->ioac
, &tsk
->ioac
);
125 sig
= NULL
; /* Marker for below. */
128 __unhash_process(tsk
);
131 * Do this under ->siglock, we can race with another thread
132 * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
134 flush_sigqueue(&tsk
->pending
);
138 spin_unlock(&sighand
->siglock
);
140 __cleanup_sighand(sighand
);
141 clear_tsk_thread_flag(tsk
,TIF_SIGPENDING
);
143 flush_sigqueue(&sig
->shared_pending
);
144 taskstats_tgid_free(sig
);
146 * Make sure ->signal can't go away under rq->lock,
147 * see account_group_exec_runtime().
149 task_rq_unlock_wait(tsk
);
150 __cleanup_signal(sig
);
154 static void delayed_put_task_struct(struct rcu_head
*rhp
)
156 struct task_struct
*tsk
= container_of(rhp
, struct task_struct
, rcu
);
158 trace_sched_process_free(tsk
);
159 put_task_struct(tsk
);
163 void release_task(struct task_struct
* p
)
165 struct task_struct
*leader
;
168 tracehook_prepare_release_task(p
);
169 /* don't need to get the RCU readlock here - the process is dead and
170 * can't be modifying its own credentials */
171 atomic_dec(&__task_cred(p
)->user
->processes
);
174 write_lock_irq(&tasklist_lock
);
175 tracehook_finish_release_task(p
);
179 * If we are the last non-leader member of the thread
180 * group, and the leader is zombie, then notify the
181 * group leader's parent process. (if it wants notification.)
184 leader
= p
->group_leader
;
185 if (leader
!= p
&& thread_group_empty(leader
) && leader
->exit_state
== EXIT_ZOMBIE
) {
186 BUG_ON(task_detached(leader
));
187 do_notify_parent(leader
, leader
->exit_signal
);
189 * If we were the last child thread and the leader has
190 * exited already, and the leader's parent ignores SIGCHLD,
191 * then we are the one who should release the leader.
193 * do_notify_parent() will have marked it self-reaping in
196 zap_leader
= task_detached(leader
);
199 * This maintains the invariant that release_task()
200 * only runs on a task in EXIT_DEAD, just for sanity.
203 leader
->exit_state
= EXIT_DEAD
;
206 write_unlock_irq(&tasklist_lock
);
208 call_rcu(&p
->rcu
, delayed_put_task_struct
);
211 if (unlikely(zap_leader
))
216 * This checks not only the pgrp, but falls back on the pid if no
217 * satisfactory pgrp is found. I dunno - gdb doesn't work correctly
220 * The caller must hold rcu lock or the tasklist lock.
222 struct pid
*session_of_pgrp(struct pid
*pgrp
)
224 struct task_struct
*p
;
225 struct pid
*sid
= NULL
;
227 p
= pid_task(pgrp
, PIDTYPE_PGID
);
229 p
= pid_task(pgrp
, PIDTYPE_PID
);
231 sid
= task_session(p
);
237 * Determine if a process group is "orphaned", according to the POSIX
238 * definition in 2.2.2.52. Orphaned process groups are not to be affected
239 * by terminal-generated stop signals. Newly orphaned process groups are
240 * to receive a SIGHUP and a SIGCONT.
242 * "I ask you, have you ever known what it is to be an orphan?"
244 static int will_become_orphaned_pgrp(struct pid
*pgrp
, struct task_struct
*ignored_task
)
246 struct task_struct
*p
;
248 do_each_pid_task(pgrp
, PIDTYPE_PGID
, p
) {
249 if ((p
== ignored_task
) ||
250 (p
->exit_state
&& thread_group_empty(p
)) ||
251 is_global_init(p
->real_parent
))
254 if (task_pgrp(p
->real_parent
) != pgrp
&&
255 task_session(p
->real_parent
) == task_session(p
))
257 } while_each_pid_task(pgrp
, PIDTYPE_PGID
, p
);
262 int is_current_pgrp_orphaned(void)
266 read_lock(&tasklist_lock
);
267 retval
= will_become_orphaned_pgrp(task_pgrp(current
), NULL
);
268 read_unlock(&tasklist_lock
);
273 static int has_stopped_jobs(struct pid
*pgrp
)
276 struct task_struct
*p
;
278 do_each_pid_task(pgrp
, PIDTYPE_PGID
, p
) {
279 if (!task_is_stopped(p
))
283 } while_each_pid_task(pgrp
, PIDTYPE_PGID
, p
);
288 * Check to see if any process groups have become orphaned as
289 * a result of our exiting, and if they have any stopped jobs,
290 * send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
293 kill_orphaned_pgrp(struct task_struct
*tsk
, struct task_struct
*parent
)
295 struct pid
*pgrp
= task_pgrp(tsk
);
296 struct task_struct
*ignored_task
= tsk
;
299 /* exit: our father is in a different pgrp than
300 * we are and we were the only connection outside.
302 parent
= tsk
->real_parent
;
304 /* reparent: our child is in a different pgrp than
305 * we are, and it was the only connection outside.
309 if (task_pgrp(parent
) != pgrp
&&
310 task_session(parent
) == task_session(tsk
) &&
311 will_become_orphaned_pgrp(pgrp
, ignored_task
) &&
312 has_stopped_jobs(pgrp
)) {
313 __kill_pgrp_info(SIGHUP
, SEND_SIG_PRIV
, pgrp
);
314 __kill_pgrp_info(SIGCONT
, SEND_SIG_PRIV
, pgrp
);
319 * reparent_to_kthreadd - Reparent the calling kernel thread to kthreadd
321 * If a kernel thread is launched as a result of a system call, or if
322 * it ever exits, it should generally reparent itself to kthreadd so it
323 * isn't in the way of other processes and is correctly cleaned up on exit.
325 * The various task state such as scheduling policy and priority may have
326 * been inherited from a user process, so we reset them to sane values here.
328 * NOTE that reparent_to_kthreadd() gives the caller full capabilities.
330 static void reparent_to_kthreadd(void)
332 write_lock_irq(&tasklist_lock
);
334 ptrace_unlink(current
);
335 /* Reparent to init */
336 current
->real_parent
= current
->parent
= kthreadd_task
;
337 list_move_tail(¤t
->sibling
, ¤t
->real_parent
->children
);
339 /* Set the exit signal to SIGCHLD so we signal init on exit */
340 current
->exit_signal
= SIGCHLD
;
342 if (task_nice(current
) < 0)
343 set_user_nice(current
, 0);
347 memcpy(current
->signal
->rlim
, init_task
.signal
->rlim
,
348 sizeof(current
->signal
->rlim
));
350 atomic_inc(&init_cred
.usage
);
351 commit_creds(&init_cred
);
352 write_unlock_irq(&tasklist_lock
);
355 void __set_special_pids(struct pid
*pid
)
357 struct task_struct
*curr
= current
->group_leader
;
358 pid_t nr
= pid_nr(pid
);
360 if (task_session(curr
) != pid
) {
361 change_pid(curr
, PIDTYPE_SID
, pid
);
362 set_task_session(curr
, nr
);
364 if (task_pgrp(curr
) != pid
) {
365 change_pid(curr
, PIDTYPE_PGID
, pid
);
366 set_task_pgrp(curr
, nr
);
370 static void set_special_pids(struct pid
*pid
)
372 write_lock_irq(&tasklist_lock
);
373 __set_special_pids(pid
);
374 write_unlock_irq(&tasklist_lock
);
378 * Let kernel threads use this to say that they
379 * allow a certain signal (since daemonize() will
380 * have disabled all of them by default).
382 int allow_signal(int sig
)
384 if (!valid_signal(sig
) || sig
< 1)
387 spin_lock_irq(¤t
->sighand
->siglock
);
388 sigdelset(¤t
->blocked
, sig
);
390 /* Kernel threads handle their own signals.
391 Let the signal code know it'll be handled, so
392 that they don't get converted to SIGKILL or
393 just silently dropped */
394 current
->sighand
->action
[(sig
)-1].sa
.sa_handler
= (void __user
*)2;
397 spin_unlock_irq(¤t
->sighand
->siglock
);
401 EXPORT_SYMBOL(allow_signal
);
403 int disallow_signal(int sig
)
405 if (!valid_signal(sig
) || sig
< 1)
408 spin_lock_irq(¤t
->sighand
->siglock
);
409 current
->sighand
->action
[(sig
)-1].sa
.sa_handler
= SIG_IGN
;
411 spin_unlock_irq(¤t
->sighand
->siglock
);
415 EXPORT_SYMBOL(disallow_signal
);
418 * Put all the gunge required to become a kernel thread without
419 * attached user resources in one place where it belongs.
422 void daemonize(const char *name
, ...)
425 struct fs_struct
*fs
;
428 va_start(args
, name
);
429 vsnprintf(current
->comm
, sizeof(current
->comm
), name
, args
);
433 * If we were started as result of loading a module, close all of the
434 * user space pages. We don't need them, and if we didn't close them
435 * they would be locked into memory.
439 * We don't want to have TIF_FREEZE set if the system-wide hibernation
440 * or suspend transition begins right now.
442 current
->flags
|= (PF_NOFREEZE
| PF_KTHREAD
);
444 if (current
->nsproxy
!= &init_nsproxy
) {
445 get_nsproxy(&init_nsproxy
);
446 switch_task_namespaces(current
, &init_nsproxy
);
448 set_special_pids(&init_struct_pid
);
449 proc_clear_tty(current
);
451 /* Block and flush all signals */
452 sigfillset(&blocked
);
453 sigprocmask(SIG_BLOCK
, &blocked
, NULL
);
454 flush_signals(current
);
456 /* Become as one with the init task */
458 exit_fs(current
); /* current->fs->count--; */
461 atomic_inc(&fs
->count
);
464 current
->files
= init_task
.files
;
465 atomic_inc(¤t
->files
->count
);
467 reparent_to_kthreadd();
470 EXPORT_SYMBOL(daemonize
);
472 static void close_files(struct files_struct
* files
)
480 * It is safe to dereference the fd table without RCU or
481 * ->file_lock because this is the last reference to the
484 fdt
= files_fdtable(files
);
488 if (i
>= fdt
->max_fds
)
490 set
= fdt
->open_fds
->fds_bits
[j
++];
493 struct file
* file
= xchg(&fdt
->fd
[i
], NULL
);
495 filp_close(file
, files
);
505 struct files_struct
*get_files_struct(struct task_struct
*task
)
507 struct files_struct
*files
;
512 atomic_inc(&files
->count
);
518 void put_files_struct(struct files_struct
*files
)
522 if (atomic_dec_and_test(&files
->count
)) {
525 * Free the fd and fdset arrays if we expanded them.
526 * If the fdtable was embedded, pass files for freeing
527 * at the end of the RCU grace period. Otherwise,
528 * you can free files immediately.
530 fdt
= files_fdtable(files
);
531 if (fdt
!= &files
->fdtab
)
532 kmem_cache_free(files_cachep
, files
);
537 void reset_files_struct(struct files_struct
*files
)
539 struct task_struct
*tsk
= current
;
540 struct files_struct
*old
;
546 put_files_struct(old
);
549 void exit_files(struct task_struct
*tsk
)
551 struct files_struct
* files
= tsk
->files
;
557 put_files_struct(files
);
561 void put_fs_struct(struct fs_struct
*fs
)
563 /* No need to hold fs->lock if we are killing it */
564 if (atomic_dec_and_test(&fs
->count
)) {
567 kmem_cache_free(fs_cachep
, fs
);
571 void exit_fs(struct task_struct
*tsk
)
573 struct fs_struct
* fs
= tsk
->fs
;
583 EXPORT_SYMBOL_GPL(exit_fs
);
585 #ifdef CONFIG_MM_OWNER
587 * Task p is exiting and it owned mm, lets find a new owner for it
590 mm_need_new_owner(struct mm_struct
*mm
, struct task_struct
*p
)
593 * If there are other users of the mm and the owner (us) is exiting
594 * we need to find a new owner to take on the responsibility.
596 if (atomic_read(&mm
->mm_users
) <= 1)
603 void mm_update_next_owner(struct mm_struct
*mm
)
605 struct task_struct
*c
, *g
, *p
= current
;
608 if (!mm_need_new_owner(mm
, p
))
611 read_lock(&tasklist_lock
);
613 * Search in the children
615 list_for_each_entry(c
, &p
->children
, sibling
) {
617 goto assign_new_owner
;
621 * Search in the siblings
623 list_for_each_entry(c
, &p
->parent
->children
, sibling
) {
625 goto assign_new_owner
;
629 * Search through everything else. We should not get
632 do_each_thread(g
, c
) {
634 goto assign_new_owner
;
635 } while_each_thread(g
, c
);
637 read_unlock(&tasklist_lock
);
639 * We found no owner yet mm_users > 1: this implies that we are
640 * most likely racing with swapoff (try_to_unuse()) or /proc or
641 * ptrace or page migration (get_task_mm()). Mark owner as NULL,
642 * so that subsystems can understand the callback and take action.
644 down_write(&mm
->mmap_sem
);
645 cgroup_mm_owner_callbacks(mm
->owner
, NULL
);
647 up_write(&mm
->mmap_sem
);
653 read_unlock(&tasklist_lock
);
654 down_write(&mm
->mmap_sem
);
656 * The task_lock protects c->mm from changing.
657 * We always want mm->owner->mm == mm
662 up_write(&mm
->mmap_sem
);
666 cgroup_mm_owner_callbacks(mm
->owner
, c
);
669 up_write(&mm
->mmap_sem
);
672 #endif /* CONFIG_MM_OWNER */
675 * Turn us into a lazy TLB process if we
678 static void exit_mm(struct task_struct
* tsk
)
680 struct mm_struct
*mm
= tsk
->mm
;
681 struct core_state
*core_state
;
687 * Serialize with any possible pending coredump.
688 * We must hold mmap_sem around checking core_state
689 * and clearing tsk->mm. The core-inducing thread
690 * will increment ->nr_threads for each thread in the
691 * group with ->mm != NULL.
693 down_read(&mm
->mmap_sem
);
694 core_state
= mm
->core_state
;
696 struct core_thread self
;
697 up_read(&mm
->mmap_sem
);
700 self
.next
= xchg(&core_state
->dumper
.next
, &self
);
702 * Implies mb(), the result of xchg() must be visible
703 * to core_state->dumper.
705 if (atomic_dec_and_test(&core_state
->nr_threads
))
706 complete(&core_state
->startup
);
709 set_task_state(tsk
, TASK_UNINTERRUPTIBLE
);
710 if (!self
.task
) /* see coredump_finish() */
714 __set_task_state(tsk
, TASK_RUNNING
);
715 down_read(&mm
->mmap_sem
);
717 atomic_inc(&mm
->mm_count
);
718 BUG_ON(mm
!= tsk
->active_mm
);
719 /* more a memory barrier than a real lock */
722 up_read(&mm
->mmap_sem
);
723 enter_lazy_tlb(mm
, current
);
724 /* We don't want this task to be frozen prematurely */
725 clear_freeze_flag(tsk
);
727 mm_update_next_owner(mm
);
732 * Return nonzero if @parent's children should reap themselves.
734 * Called with write_lock_irq(&tasklist_lock) held.
736 static int ignoring_children(struct task_struct
*parent
)
739 struct sighand_struct
*psig
= parent
->sighand
;
741 spin_lock_irqsave(&psig
->siglock
, flags
);
742 ret
= (psig
->action
[SIGCHLD
-1].sa
.sa_handler
== SIG_IGN
||
743 (psig
->action
[SIGCHLD
-1].sa
.sa_flags
& SA_NOCLDWAIT
));
744 spin_unlock_irqrestore(&psig
->siglock
, flags
);
749 * Detach all tasks we were using ptrace on.
750 * Any that need to be release_task'd are put on the @dead list.
752 * Called with write_lock(&tasklist_lock) held.
754 static void ptrace_exit(struct task_struct
*parent
, struct list_head
*dead
)
756 struct task_struct
*p
, *n
;
759 list_for_each_entry_safe(p
, n
, &parent
->ptraced
, ptrace_entry
) {
762 if (p
->exit_state
!= EXIT_ZOMBIE
)
766 * If it's a zombie, our attachedness prevented normal
767 * parent notification or self-reaping. Do notification
768 * now if it would have happened earlier. If it should
769 * reap itself, add it to the @dead list. We can't call
770 * release_task() here because we already hold tasklist_lock.
772 * If it's our own child, there is no notification to do.
773 * But if our normal children self-reap, then this child
774 * was prevented by ptrace and we must reap it now.
776 if (!task_detached(p
) && thread_group_empty(p
)) {
777 if (!same_thread_group(p
->real_parent
, parent
))
778 do_notify_parent(p
, p
->exit_signal
);
781 ign
= ignoring_children(parent
);
787 if (task_detached(p
)) {
789 * Mark it as in the process of being reaped.
791 p
->exit_state
= EXIT_DEAD
;
792 list_add(&p
->ptrace_entry
, dead
);
798 * Finish up exit-time ptrace cleanup.
800 * Called without locks.
802 static void ptrace_exit_finish(struct task_struct
*parent
,
803 struct list_head
*dead
)
805 struct task_struct
*p
, *n
;
807 BUG_ON(!list_empty(&parent
->ptraced
));
809 list_for_each_entry_safe(p
, n
, dead
, ptrace_entry
) {
810 list_del_init(&p
->ptrace_entry
);
815 static void reparent_thread(struct task_struct
*p
, struct task_struct
*father
)
817 if (p
->pdeath_signal
)
818 /* We already hold the tasklist_lock here. */
819 group_send_sig_info(p
->pdeath_signal
, SEND_SIG_NOINFO
, p
);
821 list_move_tail(&p
->sibling
, &p
->real_parent
->children
);
823 /* If this is a threaded reparent there is no need to
824 * notify anyone anything has happened.
826 if (same_thread_group(p
->real_parent
, father
))
829 /* We don't want people slaying init. */
830 if (!task_detached(p
))
831 p
->exit_signal
= SIGCHLD
;
833 /* If we'd notified the old parent about this child's death,
834 * also notify the new parent.
836 if (!ptrace_reparented(p
) &&
837 p
->exit_state
== EXIT_ZOMBIE
&&
838 !task_detached(p
) && thread_group_empty(p
))
839 do_notify_parent(p
, p
->exit_signal
);
841 kill_orphaned_pgrp(p
, father
);
845 * When we die, we re-parent all our children.
846 * Try to give them to another thread in our thread
847 * group, and if no such member exists, give it to
848 * the child reaper process (ie "init") in our pid
851 static struct task_struct
*find_new_reaper(struct task_struct
*father
)
853 struct pid_namespace
*pid_ns
= task_active_pid_ns(father
);
854 struct task_struct
*thread
;
857 while_each_thread(father
, thread
) {
858 if (thread
->flags
& PF_EXITING
)
860 if (unlikely(pid_ns
->child_reaper
== father
))
861 pid_ns
->child_reaper
= thread
;
865 if (unlikely(pid_ns
->child_reaper
== father
)) {
866 write_unlock_irq(&tasklist_lock
);
867 if (unlikely(pid_ns
== &init_pid_ns
))
868 panic("Attempted to kill init!");
870 zap_pid_ns_processes(pid_ns
);
871 write_lock_irq(&tasklist_lock
);
873 * We can not clear ->child_reaper or leave it alone.
874 * There may by stealth EXIT_DEAD tasks on ->children,
875 * forget_original_parent() must move them somewhere.
877 pid_ns
->child_reaper
= init_pid_ns
.child_reaper
;
880 return pid_ns
->child_reaper
;
883 static void forget_original_parent(struct task_struct
*father
)
885 struct task_struct
*p
, *n
, *reaper
;
886 LIST_HEAD(ptrace_dead
);
888 write_lock_irq(&tasklist_lock
);
889 reaper
= find_new_reaper(father
);
891 * First clean up ptrace if we were using it.
893 ptrace_exit(father
, &ptrace_dead
);
895 list_for_each_entry_safe(p
, n
, &father
->children
, sibling
) {
896 p
->real_parent
= reaper
;
897 if (p
->parent
== father
) {
899 p
->parent
= p
->real_parent
;
901 reparent_thread(p
, father
);
904 write_unlock_irq(&tasklist_lock
);
905 BUG_ON(!list_empty(&father
->children
));
907 ptrace_exit_finish(father
, &ptrace_dead
);
911 * Send signals to all our closest relatives so that they know
912 * to properly mourn us..
914 static void exit_notify(struct task_struct
*tsk
, int group_dead
)
920 * This does two things:
922 * A. Make init inherit all the child processes
923 * B. Check to see if any process groups have become orphaned
924 * as a result of our exiting, and if they have any stopped
925 * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
927 forget_original_parent(tsk
);
928 exit_task_namespaces(tsk
);
930 write_lock_irq(&tasklist_lock
);
932 kill_orphaned_pgrp(tsk
->group_leader
, NULL
);
934 /* Let father know we died
936 * Thread signals are configurable, but you aren't going to use
937 * that to send signals to arbitary processes.
938 * That stops right now.
940 * If the parent exec id doesn't match the exec id we saved
941 * when we started then we know the parent has changed security
944 * If our self_exec id doesn't match our parent_exec_id then
945 * we have changed execution domain as these two values started
946 * the same after a fork.
948 if (tsk
->exit_signal
!= SIGCHLD
&& !task_detached(tsk
) &&
949 (tsk
->parent_exec_id
!= tsk
->real_parent
->self_exec_id
||
950 tsk
->self_exec_id
!= tsk
->parent_exec_id
) &&
952 tsk
->exit_signal
= SIGCHLD
;
954 signal
= tracehook_notify_death(tsk
, &cookie
, group_dead
);
956 signal
= do_notify_parent(tsk
, signal
);
958 tsk
->exit_state
= signal
== DEATH_REAP
? EXIT_DEAD
: EXIT_ZOMBIE
;
960 /* mt-exec, de_thread() is waiting for us */
961 if (thread_group_leader(tsk
) &&
962 tsk
->signal
->group_exit_task
&&
963 tsk
->signal
->notify_count
< 0)
964 wake_up_process(tsk
->signal
->group_exit_task
);
966 write_unlock_irq(&tasklist_lock
);
968 tracehook_report_death(tsk
, signal
, cookie
, group_dead
);
970 /* If the process is dead, release it - nobody will wait for it */
971 if (signal
== DEATH_REAP
)
975 #ifdef CONFIG_DEBUG_STACK_USAGE
976 static void check_stack_usage(void)
978 static DEFINE_SPINLOCK(low_water_lock
);
979 static int lowest_to_date
= THREAD_SIZE
;
980 unsigned long *n
= end_of_stack(current
);
985 free
= (unsigned long)n
- (unsigned long)end_of_stack(current
);
987 if (free
>= lowest_to_date
)
990 spin_lock(&low_water_lock
);
991 if (free
< lowest_to_date
) {
992 printk(KERN_WARNING
"%s used greatest stack depth: %lu bytes "
994 current
->comm
, free
);
995 lowest_to_date
= free
;
997 spin_unlock(&low_water_lock
);
1000 static inline void check_stack_usage(void) {}
1003 NORET_TYPE
void do_exit(long code
)
1005 struct task_struct
*tsk
= current
;
1008 profile_task_exit(tsk
);
1010 WARN_ON(atomic_read(&tsk
->fs_excl
));
1012 if (unlikely(in_interrupt()))
1013 panic("Aiee, killing interrupt handler!");
1014 if (unlikely(!tsk
->pid
))
1015 panic("Attempted to kill the idle task!");
1017 tracehook_report_exit(&code
);
1020 * We're taking recursive faults here in do_exit. Safest is to just
1021 * leave this task alone and wait for reboot.
1023 if (unlikely(tsk
->flags
& PF_EXITING
)) {
1025 "Fixing recursive fault but reboot is needed!\n");
1027 * We can do this unlocked here. The futex code uses
1028 * this flag just to verify whether the pi state
1029 * cleanup has been done or not. In the worst case it
1030 * loops once more. We pretend that the cleanup was
1031 * done as there is no way to return. Either the
1032 * OWNER_DIED bit is set by now or we push the blocked
1033 * task into the wait for ever nirwana as well.
1035 tsk
->flags
|= PF_EXITPIDONE
;
1036 if (tsk
->io_context
)
1038 set_current_state(TASK_UNINTERRUPTIBLE
);
1042 exit_signals(tsk
); /* sets PF_EXITING */
1044 * tsk->flags are checked in the futex code to protect against
1045 * an exiting task cleaning up the robust pi futexes.
1048 spin_unlock_wait(&tsk
->pi_lock
);
1050 if (unlikely(in_atomic()))
1051 printk(KERN_INFO
"note: %s[%d] exited with preempt_count %d\n",
1052 current
->comm
, task_pid_nr(current
),
1055 acct_update_integrals(tsk
);
1057 update_hiwater_rss(tsk
->mm
);
1058 update_hiwater_vm(tsk
->mm
);
1060 group_dead
= atomic_dec_and_test(&tsk
->signal
->live
);
1062 hrtimer_cancel(&tsk
->signal
->real_timer
);
1063 exit_itimers(tsk
->signal
);
1065 acct_collect(code
, group_dead
);
1068 if (unlikely(tsk
->audit_context
))
1071 tsk
->exit_code
= code
;
1072 taskstats_exit(tsk
, group_dead
);
1078 trace_sched_process_exit(tsk
);
1083 check_stack_usage();
1085 cgroup_exit(tsk
, 1);
1087 if (group_dead
&& tsk
->signal
->leader
)
1088 disassociate_ctty(1);
1090 module_put(task_thread_info(tsk
)->exec_domain
->module
);
1092 module_put(tsk
->binfmt
->module
);
1094 proc_exit_connector(tsk
);
1095 exit_notify(tsk
, group_dead
);
1097 mpol_put(tsk
->mempolicy
);
1098 tsk
->mempolicy
= NULL
;
1102 * This must happen late, after the PID is not
1105 if (unlikely(!list_empty(&tsk
->pi_state_list
)))
1106 exit_pi_state_list(tsk
);
1107 if (unlikely(current
->pi_state_cache
))
1108 kfree(current
->pi_state_cache
);
1111 * Make sure we are holding no locks:
1113 debug_check_no_locks_held(tsk
);
1115 * We can do this unlocked here. The futex code uses this flag
1116 * just to verify whether the pi state cleanup has been done
1117 * or not. In the worst case it loops once more.
1119 tsk
->flags
|= PF_EXITPIDONE
;
1121 if (tsk
->io_context
)
1124 if (tsk
->splice_pipe
)
1125 __free_pipe_info(tsk
->splice_pipe
);
1128 /* causes final put_task_struct in finish_task_switch(). */
1129 tsk
->state
= TASK_DEAD
;
1133 /* Avoid "noreturn function does return". */
1135 cpu_relax(); /* For when BUG is null */
1138 EXPORT_SYMBOL_GPL(do_exit
);
1140 NORET_TYPE
void complete_and_exit(struct completion
*comp
, long code
)
1148 EXPORT_SYMBOL(complete_and_exit
);
1150 asmlinkage
long sys_exit(int error_code
)
1152 do_exit((error_code
&0xff)<<8);
1156 * Take down every thread in the group. This is called by fatal signals
1157 * as well as by sys_exit_group (below).
1160 do_group_exit(int exit_code
)
1162 struct signal_struct
*sig
= current
->signal
;
1164 BUG_ON(exit_code
& 0x80); /* core dumps don't get here */
1166 if (signal_group_exit(sig
))
1167 exit_code
= sig
->group_exit_code
;
1168 else if (!thread_group_empty(current
)) {
1169 struct sighand_struct
*const sighand
= current
->sighand
;
1170 spin_lock_irq(&sighand
->siglock
);
1171 if (signal_group_exit(sig
))
1172 /* Another thread got here before we took the lock. */
1173 exit_code
= sig
->group_exit_code
;
1175 sig
->group_exit_code
= exit_code
;
1176 sig
->flags
= SIGNAL_GROUP_EXIT
;
1177 zap_other_threads(current
);
1179 spin_unlock_irq(&sighand
->siglock
);
1187 * this kills every thread in the thread group. Note that any externally
1188 * wait4()-ing process will get the correct exit code - even if this
1189 * thread is not the thread group leader.
1191 asmlinkage
void sys_exit_group(int error_code
)
1193 do_group_exit((error_code
& 0xff) << 8);
1196 static struct pid
*task_pid_type(struct task_struct
*task
, enum pid_type type
)
1198 struct pid
*pid
= NULL
;
1199 if (type
== PIDTYPE_PID
)
1200 pid
= task
->pids
[type
].pid
;
1201 else if (type
< PIDTYPE_MAX
)
1202 pid
= task
->group_leader
->pids
[type
].pid
;
1206 static int eligible_child(enum pid_type type
, struct pid
*pid
, int options
,
1207 struct task_struct
*p
)
1211 if (type
< PIDTYPE_MAX
) {
1212 if (task_pid_type(p
, type
) != pid
)
1216 /* Wait for all children (clone and not) if __WALL is set;
1217 * otherwise, wait for clone children *only* if __WCLONE is
1218 * set; otherwise, wait for non-clone children *only*. (Note:
1219 * A "clone" child here is one that reports to its parent
1220 * using a signal other than SIGCHLD.) */
1221 if (((p
->exit_signal
!= SIGCHLD
) ^ ((options
& __WCLONE
) != 0))
1222 && !(options
& __WALL
))
1225 err
= security_task_wait(p
);
1232 static int wait_noreap_copyout(struct task_struct
*p
, pid_t pid
, uid_t uid
,
1233 int why
, int status
,
1234 struct siginfo __user
*infop
,
1235 struct rusage __user
*rusagep
)
1237 int retval
= rusagep
? getrusage(p
, RUSAGE_BOTH
, rusagep
) : 0;
1241 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1243 retval
= put_user(0, &infop
->si_errno
);
1245 retval
= put_user((short)why
, &infop
->si_code
);
1247 retval
= put_user(pid
, &infop
->si_pid
);
1249 retval
= put_user(uid
, &infop
->si_uid
);
1251 retval
= put_user(status
, &infop
->si_status
);
1258 * Handle sys_wait4 work for one task in state EXIT_ZOMBIE. We hold
1259 * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
1260 * the lock and this task is uninteresting. If we return nonzero, we have
1261 * released the lock and the system call should return.
1263 static int wait_task_zombie(struct task_struct
*p
, int options
,
1264 struct siginfo __user
*infop
,
1265 int __user
*stat_addr
, struct rusage __user
*ru
)
1267 unsigned long state
;
1268 int retval
, status
, traced
;
1269 pid_t pid
= task_pid_vnr(p
);
1270 uid_t uid
= __task_cred(p
)->uid
;
1272 if (!likely(options
& WEXITED
))
1275 if (unlikely(options
& WNOWAIT
)) {
1276 int exit_code
= p
->exit_code
;
1280 read_unlock(&tasklist_lock
);
1281 if ((exit_code
& 0x7f) == 0) {
1283 status
= exit_code
>> 8;
1285 why
= (exit_code
& 0x80) ? CLD_DUMPED
: CLD_KILLED
;
1286 status
= exit_code
& 0x7f;
1288 return wait_noreap_copyout(p
, pid
, uid
, why
,
1293 * Try to move the task's state to DEAD
1294 * only one thread is allowed to do this:
1296 state
= xchg(&p
->exit_state
, EXIT_DEAD
);
1297 if (state
!= EXIT_ZOMBIE
) {
1298 BUG_ON(state
!= EXIT_DEAD
);
1302 traced
= ptrace_reparented(p
);
1304 if (likely(!traced
)) {
1305 struct signal_struct
*psig
;
1306 struct signal_struct
*sig
;
1307 struct task_cputime cputime
;
1310 * The resource counters for the group leader are in its
1311 * own task_struct. Those for dead threads in the group
1312 * are in its signal_struct, as are those for the child
1313 * processes it has previously reaped. All these
1314 * accumulate in the parent's signal_struct c* fields.
1316 * We don't bother to take a lock here to protect these
1317 * p->signal fields, because they are only touched by
1318 * __exit_signal, which runs with tasklist_lock
1319 * write-locked anyway, and so is excluded here. We do
1320 * need to protect the access to p->parent->signal fields,
1321 * as other threads in the parent group can be right
1322 * here reaping other children at the same time.
1324 * We use thread_group_cputime() to get times for the thread
1325 * group, which consolidates times for all threads in the
1326 * group including the group leader.
1328 spin_lock_irq(&p
->parent
->sighand
->siglock
);
1329 psig
= p
->parent
->signal
;
1331 thread_group_cputime(p
, &cputime
);
1333 cputime_add(psig
->cutime
,
1334 cputime_add(cputime
.utime
,
1337 cputime_add(psig
->cstime
,
1338 cputime_add(cputime
.stime
,
1341 cputime_add(psig
->cgtime
,
1342 cputime_add(p
->gtime
,
1343 cputime_add(sig
->gtime
,
1346 p
->min_flt
+ sig
->min_flt
+ sig
->cmin_flt
;
1348 p
->maj_flt
+ sig
->maj_flt
+ sig
->cmaj_flt
;
1350 p
->nvcsw
+ sig
->nvcsw
+ sig
->cnvcsw
;
1352 p
->nivcsw
+ sig
->nivcsw
+ sig
->cnivcsw
;
1354 task_io_get_inblock(p
) +
1355 sig
->inblock
+ sig
->cinblock
;
1357 task_io_get_oublock(p
) +
1358 sig
->oublock
+ sig
->coublock
;
1359 task_io_accounting_add(&psig
->ioac
, &p
->ioac
);
1360 task_io_accounting_add(&psig
->ioac
, &sig
->ioac
);
1361 spin_unlock_irq(&p
->parent
->sighand
->siglock
);
1365 * Now we are sure this task is interesting, and no other
1366 * thread can reap it because we set its state to EXIT_DEAD.
1368 read_unlock(&tasklist_lock
);
1370 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1371 status
= (p
->signal
->flags
& SIGNAL_GROUP_EXIT
)
1372 ? p
->signal
->group_exit_code
: p
->exit_code
;
1373 if (!retval
&& stat_addr
)
1374 retval
= put_user(status
, stat_addr
);
1375 if (!retval
&& infop
)
1376 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1377 if (!retval
&& infop
)
1378 retval
= put_user(0, &infop
->si_errno
);
1379 if (!retval
&& infop
) {
1382 if ((status
& 0x7f) == 0) {
1386 why
= (status
& 0x80) ? CLD_DUMPED
: CLD_KILLED
;
1389 retval
= put_user((short)why
, &infop
->si_code
);
1391 retval
= put_user(status
, &infop
->si_status
);
1393 if (!retval
&& infop
)
1394 retval
= put_user(pid
, &infop
->si_pid
);
1395 if (!retval
&& infop
)
1396 retval
= put_user(uid
, &infop
->si_uid
);
1401 write_lock_irq(&tasklist_lock
);
1402 /* We dropped tasklist, ptracer could die and untrace */
1405 * If this is not a detached task, notify the parent.
1406 * If it's still not detached after that, don't release
1409 if (!task_detached(p
)) {
1410 do_notify_parent(p
, p
->exit_signal
);
1411 if (!task_detached(p
)) {
1412 p
->exit_state
= EXIT_ZOMBIE
;
1416 write_unlock_irq(&tasklist_lock
);
1425 * Handle sys_wait4 work for one task in state TASK_STOPPED. We hold
1426 * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
1427 * the lock and this task is uninteresting. If we return nonzero, we have
1428 * released the lock and the system call should return.
1430 static int wait_task_stopped(int ptrace
, struct task_struct
*p
,
1431 int options
, struct siginfo __user
*infop
,
1432 int __user
*stat_addr
, struct rusage __user
*ru
)
1434 int retval
, exit_code
, why
;
1435 uid_t uid
= 0; /* unneeded, required by compiler */
1438 if (!(options
& WUNTRACED
))
1442 spin_lock_irq(&p
->sighand
->siglock
);
1444 if (unlikely(!task_is_stopped_or_traced(p
)))
1447 if (!ptrace
&& p
->signal
->group_stop_count
> 0)
1449 * A group stop is in progress and this is the group leader.
1450 * We won't report until all threads have stopped.
1454 exit_code
= p
->exit_code
;
1458 if (!unlikely(options
& WNOWAIT
))
1461 /* don't need the RCU readlock here as we're holding a spinlock */
1462 uid
= __task_cred(p
)->uid
;
1464 spin_unlock_irq(&p
->sighand
->siglock
);
1469 * Now we are pretty sure this task is interesting.
1470 * Make sure it doesn't get reaped out from under us while we
1471 * give up the lock and then examine it below. We don't want to
1472 * keep holding onto the tasklist_lock while we call getrusage and
1473 * possibly take page faults for user memory.
1476 pid
= task_pid_vnr(p
);
1477 why
= ptrace
? CLD_TRAPPED
: CLD_STOPPED
;
1478 read_unlock(&tasklist_lock
);
1480 if (unlikely(options
& WNOWAIT
))
1481 return wait_noreap_copyout(p
, pid
, uid
,
1485 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1486 if (!retval
&& stat_addr
)
1487 retval
= put_user((exit_code
<< 8) | 0x7f, stat_addr
);
1488 if (!retval
&& infop
)
1489 retval
= put_user(SIGCHLD
, &infop
->si_signo
);
1490 if (!retval
&& infop
)
1491 retval
= put_user(0, &infop
->si_errno
);
1492 if (!retval
&& infop
)
1493 retval
= put_user((short)why
, &infop
->si_code
);
1494 if (!retval
&& infop
)
1495 retval
= put_user(exit_code
, &infop
->si_status
);
1496 if (!retval
&& infop
)
1497 retval
= put_user(pid
, &infop
->si_pid
);
1498 if (!retval
&& infop
)
1499 retval
= put_user(uid
, &infop
->si_uid
);
1509 * Handle do_wait work for one task in a live, non-stopped state.
1510 * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
1511 * the lock and this task is uninteresting. If we return nonzero, we have
1512 * released the lock and the system call should return.
1514 static int wait_task_continued(struct task_struct
*p
, int options
,
1515 struct siginfo __user
*infop
,
1516 int __user
*stat_addr
, struct rusage __user
*ru
)
1522 if (!unlikely(options
& WCONTINUED
))
1525 if (!(p
->signal
->flags
& SIGNAL_STOP_CONTINUED
))
1528 spin_lock_irq(&p
->sighand
->siglock
);
1529 /* Re-check with the lock held. */
1530 if (!(p
->signal
->flags
& SIGNAL_STOP_CONTINUED
)) {
1531 spin_unlock_irq(&p
->sighand
->siglock
);
1534 if (!unlikely(options
& WNOWAIT
))
1535 p
->signal
->flags
&= ~SIGNAL_STOP_CONTINUED
;
1536 uid
= __task_cred(p
)->uid
;
1537 spin_unlock_irq(&p
->sighand
->siglock
);
1539 pid
= task_pid_vnr(p
);
1541 read_unlock(&tasklist_lock
);
1544 retval
= ru
? getrusage(p
, RUSAGE_BOTH
, ru
) : 0;
1546 if (!retval
&& stat_addr
)
1547 retval
= put_user(0xffff, stat_addr
);
1551 retval
= wait_noreap_copyout(p
, pid
, uid
,
1552 CLD_CONTINUED
, SIGCONT
,
1554 BUG_ON(retval
== 0);
1561 * Consider @p for a wait by @parent.
1563 * -ECHILD should be in *@notask_error before the first call.
1564 * Returns nonzero for a final return, when we have unlocked tasklist_lock.
1565 * Returns zero if the search for a child should continue;
1566 * then *@notask_error is 0 if @p is an eligible child,
1567 * or another error from security_task_wait(), or still -ECHILD.
1569 static int wait_consider_task(struct task_struct
*parent
, int ptrace
,
1570 struct task_struct
*p
, int *notask_error
,
1571 enum pid_type type
, struct pid
*pid
, int options
,
1572 struct siginfo __user
*infop
,
1573 int __user
*stat_addr
, struct rusage __user
*ru
)
1575 int ret
= eligible_child(type
, pid
, options
, p
);
1579 if (unlikely(ret
< 0)) {
1581 * If we have not yet seen any eligible child,
1582 * then let this error code replace -ECHILD.
1583 * A permission error will give the user a clue
1584 * to look for security policy problems, rather
1585 * than for mysterious wait bugs.
1588 *notask_error
= ret
;
1591 if (likely(!ptrace
) && unlikely(p
->ptrace
)) {
1593 * This child is hidden by ptrace.
1594 * We aren't allowed to see it now, but eventually we will.
1600 if (p
->exit_state
== EXIT_DEAD
)
1604 * We don't reap group leaders with subthreads.
1606 if (p
->exit_state
== EXIT_ZOMBIE
&& !delay_group_leader(p
))
1607 return wait_task_zombie(p
, options
, infop
, stat_addr
, ru
);
1610 * It's stopped or running now, so it might
1611 * later continue, exit, or stop again.
1615 if (task_is_stopped_or_traced(p
))
1616 return wait_task_stopped(ptrace
, p
, options
,
1617 infop
, stat_addr
, ru
);
1619 return wait_task_continued(p
, options
, infop
, stat_addr
, ru
);
1623 * Do the work of do_wait() for one thread in the group, @tsk.
1625 * -ECHILD should be in *@notask_error before the first call.
1626 * Returns nonzero for a final return, when we have unlocked tasklist_lock.
1627 * Returns zero if the search for a child should continue; then
1628 * *@notask_error is 0 if there were any eligible children,
1629 * or another error from security_task_wait(), or still -ECHILD.
1631 static int do_wait_thread(struct task_struct
*tsk
, int *notask_error
,
1632 enum pid_type type
, struct pid
*pid
, int options
,
1633 struct siginfo __user
*infop
, int __user
*stat_addr
,
1634 struct rusage __user
*ru
)
1636 struct task_struct
*p
;
1638 list_for_each_entry(p
, &tsk
->children
, sibling
) {
1640 * Do not consider detached threads.
1642 if (!task_detached(p
)) {
1643 int ret
= wait_consider_task(tsk
, 0, p
, notask_error
,
1645 infop
, stat_addr
, ru
);
1654 static int ptrace_do_wait(struct task_struct
*tsk
, int *notask_error
,
1655 enum pid_type type
, struct pid
*pid
, int options
,
1656 struct siginfo __user
*infop
, int __user
*stat_addr
,
1657 struct rusage __user
*ru
)
1659 struct task_struct
*p
;
1662 * Traditionally we see ptrace'd stopped tasks regardless of options.
1664 options
|= WUNTRACED
;
1666 list_for_each_entry(p
, &tsk
->ptraced
, ptrace_entry
) {
1667 int ret
= wait_consider_task(tsk
, 1, p
, notask_error
,
1669 infop
, stat_addr
, ru
);
1677 static long do_wait(enum pid_type type
, struct pid
*pid
, int options
,
1678 struct siginfo __user
*infop
, int __user
*stat_addr
,
1679 struct rusage __user
*ru
)
1681 DECLARE_WAITQUEUE(wait
, current
);
1682 struct task_struct
*tsk
;
1685 trace_sched_process_wait(pid
);
1687 add_wait_queue(¤t
->signal
->wait_chldexit
,&wait
);
1690 * If there is nothing that can match our critiera just get out.
1691 * We will clear @retval to zero if we see any child that might later
1692 * match our criteria, even if we are not able to reap it yet.
1695 if ((type
< PIDTYPE_MAX
) && (!pid
|| hlist_empty(&pid
->tasks
[type
])))
1698 current
->state
= TASK_INTERRUPTIBLE
;
1699 read_lock(&tasklist_lock
);
1702 int tsk_result
= do_wait_thread(tsk
, &retval
,
1704 infop
, stat_addr
, ru
);
1706 tsk_result
= ptrace_do_wait(tsk
, &retval
,
1708 infop
, stat_addr
, ru
);
1711 * tasklist_lock is unlocked and we have a final result.
1713 retval
= tsk_result
;
1717 if (options
& __WNOTHREAD
)
1719 tsk
= next_thread(tsk
);
1720 BUG_ON(tsk
->signal
!= current
->signal
);
1721 } while (tsk
!= current
);
1722 read_unlock(&tasklist_lock
);
1724 if (!retval
&& !(options
& WNOHANG
)) {
1725 retval
= -ERESTARTSYS
;
1726 if (!signal_pending(current
)) {
1733 current
->state
= TASK_RUNNING
;
1734 remove_wait_queue(¤t
->signal
->wait_chldexit
,&wait
);
1740 * For a WNOHANG return, clear out all the fields
1741 * we would set so the user can easily tell the
1745 retval
= put_user(0, &infop
->si_signo
);
1747 retval
= put_user(0, &infop
->si_errno
);
1749 retval
= put_user(0, &infop
->si_code
);
1751 retval
= put_user(0, &infop
->si_pid
);
1753 retval
= put_user(0, &infop
->si_uid
);
1755 retval
= put_user(0, &infop
->si_status
);
1761 asmlinkage
long sys_waitid(int which
, pid_t upid
,
1762 struct siginfo __user
*infop
, int options
,
1763 struct rusage __user
*ru
)
1765 struct pid
*pid
= NULL
;
1769 if (options
& ~(WNOHANG
|WNOWAIT
|WEXITED
|WSTOPPED
|WCONTINUED
))
1771 if (!(options
& (WEXITED
|WSTOPPED
|WCONTINUED
)))
1784 type
= PIDTYPE_PGID
;
1792 if (type
< PIDTYPE_MAX
)
1793 pid
= find_get_pid(upid
);
1794 ret
= do_wait(type
, pid
, options
, infop
, NULL
, ru
);
1797 /* avoid REGPARM breakage on x86: */
1798 asmlinkage_protect(5, ret
, which
, upid
, infop
, options
, ru
);
1802 asmlinkage
long sys_wait4(pid_t upid
, int __user
*stat_addr
,
1803 int options
, struct rusage __user
*ru
)
1805 struct pid
*pid
= NULL
;
1809 if (options
& ~(WNOHANG
|WUNTRACED
|WCONTINUED
|
1810 __WNOTHREAD
|__WCLONE
|__WALL
))
1815 else if (upid
< 0) {
1816 type
= PIDTYPE_PGID
;
1817 pid
= find_get_pid(-upid
);
1818 } else if (upid
== 0) {
1819 type
= PIDTYPE_PGID
;
1820 pid
= get_pid(task_pgrp(current
));
1821 } else /* upid > 0 */ {
1823 pid
= find_get_pid(upid
);
1826 ret
= do_wait(type
, pid
, options
| WEXITED
, NULL
, stat_addr
, ru
);
1829 /* avoid REGPARM breakage on x86: */
1830 asmlinkage_protect(4, ret
, upid
, stat_addr
, options
, ru
);
1834 #ifdef __ARCH_WANT_SYS_WAITPID
1837 * sys_waitpid() remains for compatibility. waitpid() should be
1838 * implemented by calling sys_wait4() from libc.a.
1840 asmlinkage
long sys_waitpid(pid_t pid
, int __user
*stat_addr
, int options
)
1842 return sys_wait4(pid
, stat_addr
, options
, NULL
);
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