* Copyright (C) 1991, 1992 Linus Torvalds
*/
-#include <linux/config.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/file.h>
#include <linux/binfmts.h>
#include <linux/ptrace.h>
+#include <linux/tracehook.h>
#include <linux/profile.h>
#include <linux/mount.h>
#include <linux/proc_fs.h>
#include <linux/mempolicy.h>
+#include <linux/taskstats_kern.h>
+#include <linux/delayacct.h>
#include <linux/cpuset.h>
#include <linux/syscalls.h>
#include <linux/signal.h>
#include <linux/compat.h>
#include <linux/pipe_fs_i.h>
#include <linux/audit.h> /* for audit_free() */
+#include <linux/resource.h>
#include <linux/vs_limit.h>
#include <linux/vs_context.h>
#include <linux/vs_network.h>
-#include <linux/vs_cvirt.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
extern void sem_exit (void);
extern struct task_struct *child_reaper;
-int getrusage(struct task_struct *, int, struct rusage __user *);
-
static void exit_mm(struct task_struct * tsk);
static void __unhash_process(struct task_struct *p)
void release_task(struct task_struct * p)
{
+ struct task_struct *leader;
int zap_leader;
- task_t *leader;
- struct dentry *proc_dentry;
-
repeat:
+ tracehook_release_task(p);
atomic_dec(&p->user->processes);
- spin_lock(&p->proc_lock);
- proc_dentry = proc_pid_unhash(p);
write_lock_irq(&tasklist_lock);
- ptrace_unlink(p);
- BUG_ON(!list_empty(&p->ptrace_list) || !list_empty(&p->ptrace_children));
+ BUG_ON(tracehook_check_released(p));
__exit_signal(p);
/*
sched_exit(p);
write_unlock_irq(&tasklist_lock);
- spin_unlock(&p->proc_lock);
- proc_pid_flush(proc_dentry);
+ proc_flush_task(p);
release_thread(p);
call_rcu(&p->rcu, delayed_put_task_struct);
*
* "I ask you, have you ever known what it is to be an orphan?"
*/
-static int will_become_orphaned_pgrp(int pgrp, task_t *ignored_task)
+static int will_become_orphaned_pgrp(int pgrp, struct task_struct *ignored_task)
{
struct task_struct *p;
int ret = 1;
do_each_task_pid(pgrp, PIDTYPE_PGID, p) {
if (p == ignored_task
|| p->exit_state
- || p->real_parent->pid == 1)
+ || p->parent->pid == 1)
continue;
- if (process_group(p->real_parent) != pgrp
- && p->real_parent->signal->session == p->signal->session) {
+ if (process_group(p->parent) != pgrp
+ && p->parent->signal->session == p->signal->session) {
ret = 0;
break;
}
if (p->state != TASK_STOPPED)
continue;
- /* If p is stopped by a debugger on a signal that won't
- stop it, then don't count p as stopped. This isn't
- perfect but it's a good approximation. */
- if (unlikely (p->ptrace)
- && p->exit_code != SIGSTOP
- && p->exit_code != SIGTSTP
- && p->exit_code != SIGTTOU
- && p->exit_code != SIGTTIN)
- continue;
-
retval = 1;
break;
} while_each_task_pid(pgrp, PIDTYPE_PGID, p);
{
write_lock_irq(&tasklist_lock);
- ptrace_unlink(current);
/* Reparent to init */
remove_parent(current);
current->parent = child_reaper;
- current->real_parent = child_reaper;
add_parent(current);
/* Set the exit signal to SIGCHLD so we signal init on exit */
down_read(&mm->mmap_sem);
}
atomic_inc(&mm->mm_count);
- if (mm != tsk->active_mm) BUG();
+ BUG_ON(mm != tsk->active_mm);
/* more a memory barrier than a real lock */
task_lock(tsk);
tsk->mm = NULL;
mmput(mm);
}
-static inline void choose_new_parent(task_t *p, task_t *reaper)
+static inline void
+choose_new_parent(struct task_struct *p, struct task_struct *reaper)
{
/* check for reaper context */
vxwprintk((p->xid != reaper->xid) && (reaper != child_reaper),
* the parent is not a zombie.
*/
BUG_ON(p == reaper || reaper->exit_state);
- p->real_parent = reaper;
+ p->parent = reaper;
}
-static void reparent_thread(task_t *p, task_t *father, int traced)
+static void
+reparent_thread(struct task_struct *p, struct task_struct *father)
{
/* We don't want people slaying init. */
if (p->exit_signal != -1)
group_send_sig_info(p->pdeath_signal, SEND_SIG_NOINFO, p);
/* Move the child from its dying parent to the new one. */
- if (unlikely(traced)) {
- /* Preserve ptrace links if someone else is tracing this child. */
- list_del_init(&p->ptrace_list);
- if (p->parent != p->real_parent)
- list_add(&p->ptrace_list, &p->real_parent->ptrace_children);
- } else {
- /* If this child is being traced, then we're the one tracing it
- * anyway, so let go of it.
- */
- p->ptrace = 0;
- remove_parent(p);
- p->parent = p->real_parent;
- add_parent(p);
+ list_move_tail(&p->sibling, &p->parent->children);
- /* If we'd notified the old parent about this child's death,
- * also notify the new parent.
- */
- if (p->exit_state == EXIT_ZOMBIE && p->exit_signal != -1 &&
- thread_group_empty(p))
- do_notify_parent(p, p->exit_signal);
- else if (p->state == TASK_TRACED) {
- /*
- * If it was at a trace stop, turn it into
- * a normal stop since it's no longer being
- * traced.
- */
- ptrace_untrace(p);
- }
- }
+ /* If we'd notified the old parent about this child's death,
+ * also notify the new parent.
+ */
+ if (p->exit_state == EXIT_ZOMBIE && p->exit_signal != -1 &&
+ thread_group_empty(p))
+ do_notify_parent(p, p->exit_signal);
/*
* process group orphan check
* group, and if no such member exists, give it to
* the global child reaper process (ie "init")
*/
-static void forget_original_parent(struct task_struct * father,
- struct list_head *to_release)
+static void
+forget_original_parent(struct task_struct *father)
{
struct task_struct *p, *reaper = father;
struct list_head *_p, *_n;
}
} while (reaper->exit_state);
- /*
- * There are only two places where our children can be:
- *
- * - in our child list
- * - in our ptraced child list
- *
- * Search them and reparent children.
- */
list_for_each_safe(_p, _n, &father->children) {
- int ptrace;
- p = list_entry(_p,struct task_struct,sibling);
-
- ptrace = p->ptrace;
-
- /* if father isn't the real parent, then ptrace must be enabled */
- BUG_ON(father != p->real_parent && !ptrace);
-
- if (father == p->real_parent) {
- /* reparent with a reaper, real father it's us */
- choose_new_parent(p, vx_child_reaper(p));
- reparent_thread(p, father, 0);
- } else {
- /* reparent ptraced task to its real parent */
- __ptrace_unlink (p);
- if (p->exit_state == EXIT_ZOMBIE && p->exit_signal != -1 &&
- thread_group_empty(p))
- do_notify_parent(p, p->exit_signal);
- }
-
- /*
- * if the ptraced child is a zombie with exit_signal == -1
- * we must collect it before we exit, or it will remain
- * zombie forever since we prevented it from self-reap itself
- * while it was being traced by us, to be able to see it in wait4.
- */
- if (unlikely(ptrace && p->exit_state == EXIT_ZOMBIE && p->exit_signal == -1))
- list_add(&p->ptrace_list, to_release);
- }
- list_for_each_safe(_p, _n, &father->ptrace_children) {
- p = list_entry(_p,struct task_struct,ptrace_list);
- choose_new_parent(p, reaper);
- reparent_thread(p, father, 1);
+ p = list_entry(_p, struct task_struct, sibling);
+ choose_new_parent(p, vx_child_reaper(p));
+ reparent_thread(p, father);
}
}
{
int state;
struct task_struct *t;
- struct list_head ptrace_dead, *_p, *_n;
+ int noreap;
+ void *cookie;
if (signal_pending(tsk) && !(tsk->signal->flags & SIGNAL_GROUP_EXIT)
&& !thread_group_empty(tsk)) {
* jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
*/
- INIT_LIST_HEAD(&ptrace_dead);
- forget_original_parent(tsk, &ptrace_dead);
+ forget_original_parent(tsk);
BUG_ON(!list_empty(&tsk->children));
- BUG_ON(!list_empty(&tsk->ptrace_children));
/*
* Check to see if any process groups have become orphaned
* is about to become orphaned.
*/
- t = tsk->real_parent;
+ t = tsk->parent;
if ((process_group(t) != process_group(tsk)) &&
(t->signal->session == tsk->signal->session) &&
&& !capable(CAP_KILL))
tsk->exit_signal = SIGCHLD;
-
- /* If something other than our normal parent is ptracing us, then
- * send it a SIGCHLD instead of honoring exit_signal. exit_signal
- * only has special meaning to our real parent.
- */
- if (tsk->exit_signal != -1 && thread_group_empty(tsk)) {
- int signal = tsk->parent == tsk->real_parent ? tsk->exit_signal : SIGCHLD;
- do_notify_parent(tsk, signal);
- } else if (tsk->ptrace) {
- do_notify_parent(tsk, SIGCHLD);
- }
+ if (!tracehook_notify_death(tsk, &noreap, &cookie)
+ && tsk->exit_signal != -1 && thread_group_empty(tsk))
+ do_notify_parent(tsk, tsk->exit_signal);
state = EXIT_ZOMBIE;
- if (tsk->exit_signal == -1 &&
- (likely(tsk->ptrace == 0) ||
- unlikely(tsk->parent->signal->flags & SIGNAL_GROUP_EXIT)))
+ if (tsk->exit_signal == -1 && !noreap)
state = EXIT_DEAD;
tsk->exit_state = state;
write_unlock_irq(&tasklist_lock);
- list_for_each_safe(_p, _n, &ptrace_dead) {
- list_del_init(_p);
- t = list_entry(_p,struct task_struct,ptrace_list);
- release_task(t);
- }
+ tracehook_report_death(tsk, state, cookie);
/* If the process is dead, release it - nobody will wait for it */
if (state == EXIT_DEAD)
fastcall NORET_TYPE void do_exit(long code)
{
struct task_struct *tsk = current;
+ struct taskstats *tidstats;
int group_dead;
+ unsigned int mycpu;
profile_task_exit(tsk);
if (unlikely(tsk == child_reaper))
panic("Attempted to kill init!");
- if (unlikely(current->ptrace & PT_TRACE_EXIT)) {
- current->ptrace_message = code;
- ptrace_notify((PTRACE_EVENT_EXIT << 8) | SIGTRAP);
- }
+ tracehook_report_exit(&code);
/*
* We're taking recursive faults here in do_exit. Safest is to just
tsk->flags |= PF_EXITING;
+ ptrace_exit(tsk);
+
if (unlikely(in_atomic()))
printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n",
current->comm, current->pid,
preempt_count());
+ taskstats_exit_alloc(&tidstats, &mycpu);
+
acct_update_integrals(tsk);
if (tsk->mm) {
update_hiwater_rss(tsk->mm);
if (group_dead) {
hrtimer_cancel(&tsk->signal->real_timer);
exit_itimers(tsk->signal);
- acct_process(code);
- if (current->tux_info) {
+ }
+
+ if (current->tux_info) {
#ifdef CONFIG_TUX_DEBUG
- printk("Possibly unexpected TUX-thread exit(%ld) at %p?\n",
- code, __builtin_return_address(0));
+ printk("Possibly unexpected TUX-thread exit(%ld) at %p?\n",
+ code, __builtin_return_address(0));
#endif
- current->tux_exit();
- }
+ current->tux_exit();
}
+
+ acct_collect(code, group_dead);
if (unlikely(tsk->robust_list))
exit_robust_list(tsk);
#if defined(CONFIG_FUTEX) && defined(CONFIG_COMPAT)
#endif
if (unlikely(tsk->audit_context))
audit_free(tsk);
+ taskstats_exit_send(tsk, tidstats, group_dead, mycpu);
+ taskstats_exit_free(tidstats);
+
exit_mm(tsk);
+ if (group_dead)
+ acct_process();
exit_sem(tsk);
__exit_files(tsk);
__exit_fs(tsk);
exit_namespace(tsk);
- exit_vx_info(tsk, code);
- exit_nx_info(tsk);
exit_thread();
cpuset_exit(tsk);
exit_keys(tsk);
tsk->exit_code = code;
proc_exit_connector(tsk);
+ /* needs to stay before exit_notify() */
+ exit_vx_info_early(tsk, code);
exit_notify(tsk);
#ifdef CONFIG_NUMA
mpol_free(tsk->mempolicy);
tsk->mempolicy = NULL;
#endif
/*
- * If DEBUG_MUTEXES is on, make sure we are holding no locks:
+ * This must happen late, after the PID is not
+ * hashed anymore:
*/
- mutex_debug_check_no_locks_held(tsk);
+ if (unlikely(!list_empty(&tsk->pi_state_list)))
+ exit_pi_state_list(tsk);
+ if (unlikely(current->pi_state_cache))
+ kfree(current->pi_state_cache);
+ /*
+ * Make sure we are holding no locks:
+ */
+ debug_check_no_locks_held(tsk);
if (tsk->io_context)
exit_io_context();
if (tsk->splice_pipe)
__free_pipe_info(tsk->splice_pipe);
+ /* needs to stay after exit_notify() */
+ exit_vx_info(tsk, code);
+ exit_nx_info(tsk);
+
/* PF_DEAD causes final put_task_struct after we schedule. */
preempt_disable();
BUG_ON(tsk->flags & PF_DEAD);
do_group_exit((error_code & 0xff) << 8);
}
-static int eligible_child(pid_t pid, int options, task_t *p)
+static int eligible_child(pid_t pid, int options, struct task_struct *p)
{
if (pid > 0) {
if (p->pid != pid)
}
/*
- * Do not consider detached threads that are
- * not ptraced:
+ * Do not consider detached threads.
*/
- if (p->exit_signal == -1 && !p->ptrace)
+ if (p->exit_signal == -1)
return 0;
/* Wait for all children (clone and not) if __WALL is set;
* Do not consider thread group leaders that are
* in a non-empty thread group:
*/
- if (current->tgid != p->tgid && delay_group_leader(p))
+ if (delay_group_leader(p))
return 2;
if (security_task_wait(p))
return 1;
}
-static int wait_noreap_copyout(task_t *p, pid_t pid, uid_t uid,
+static int wait_noreap_copyout(struct task_struct *p, pid_t pid, uid_t uid,
int why, int status,
struct siginfo __user *infop,
struct rusage __user *rusagep)
{
int retval = rusagep ? getrusage(p, RUSAGE_BOTH, rusagep) : 0;
+
put_task_struct(p);
if (!retval)
retval = put_user(SIGCHLD, &infop->si_signo);
* the lock and this task is uninteresting. If we return nonzero, we have
* released the lock and the system call should return.
*/
-static int wait_task_zombie(task_t *p, int noreap,
+static int wait_task_zombie(struct task_struct *p, int noreap,
struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
if (unlikely(p->exit_state != EXIT_ZOMBIE))
return 0;
- if (unlikely(p->exit_signal == -1 && p->ptrace == 0))
+ if (unlikely(p->exit_signal == -1))
return 0;
get_task_struct(p);
read_unlock(&tasklist_lock);
BUG_ON(state != EXIT_DEAD);
return 0;
}
- if (unlikely(p->exit_signal == -1 && p->ptrace == 0)) {
- /*
- * This can only happen in a race with a ptraced thread
- * dying on another processor.
- */
- return 0;
- }
+ BUG_ON(p->exit_signal == -1);
- if (likely(p->real_parent == p->parent) && likely(p->signal)) {
+ if (likely(p->signal)) {
struct signal_struct *psig;
struct signal_struct *sig;
return retval;
}
retval = p->pid;
- if (p->real_parent != p->parent) {
- write_lock_irq(&tasklist_lock);
- /* Double-check with lock held. */
- if (p->real_parent != p->parent) {
- __ptrace_unlink(p);
- // TODO: is this safe?
- p->exit_state = EXIT_ZOMBIE;
- /*
- * If this is not a detached task, notify the parent.
- * If it's still not detached after that, don't release
- * it now.
- */
- if (p->exit_signal != -1) {
- do_notify_parent(p, p->exit_signal);
- if (p->exit_signal != -1)
- p = NULL;
- }
- }
- write_unlock_irq(&tasklist_lock);
- }
- if (p != NULL)
- release_task(p);
+ release_task(p);
+
BUG_ON(!retval);
return retval;
}
* the lock and this task is uninteresting. If we return nonzero, we have
* released the lock and the system call should return.
*/
-static int wait_task_stopped(task_t *p, int delayed_group_leader, int noreap,
- struct siginfo __user *infop,
+static int wait_task_stopped(struct task_struct *p, int delayed_group_leader,
+ int noreap, struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
int retval, exit_code;
if (!p->exit_code)
return 0;
- if (delayed_group_leader && !(p->ptrace & PT_PTRACED) &&
+ if (delayed_group_leader &&
p->signal && p->signal->group_stop_count > 0)
/*
* A group stop is in progress and this is the group leader.
if (unlikely(noreap)) {
pid_t pid = p->pid;
uid_t uid = p->uid;
- int why = (p->ptrace & PT_PTRACED) ? CLD_TRAPPED : CLD_STOPPED;
exit_code = p->exit_code;
if (unlikely(!exit_code) ||
unlikely(p->state & TASK_TRACED))
goto bail_ref;
- return wait_noreap_copyout(p, pid, uid,
- why, (exit_code << 8) | 0x7f,
+ return wait_noreap_copyout(p, pid, uid, CLD_STOPPED,
+ (exit_code << 8) | 0x7f,
infop, ru);
}
if (!retval && infop)
retval = put_user(0, &infop->si_errno);
if (!retval && infop)
- retval = put_user((short)((p->ptrace & PT_PTRACED)
- ? CLD_TRAPPED : CLD_STOPPED),
- &infop->si_code);
+ retval = put_user((short)CLD_STOPPED, &infop->si_code);
if (!retval && infop)
retval = put_user(exit_code, &infop->si_status);
if (!retval && infop)
* the lock and this task is uninteresting. If we return nonzero, we have
* released the lock and the system call should return.
*/
-static int wait_task_continued(task_t *p, int noreap,
+static int wait_task_continued(struct task_struct *p, int noreap,
struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
}
-static inline int my_ptrace_child(struct task_struct *p)
-{
- if (!(p->ptrace & PT_PTRACED))
- return 0;
- if (!(p->ptrace & PT_ATTACHED))
- return 1;
- /*
- * This child was PTRACE_ATTACH'd. We should be seeing it only if
- * we are the attacher. If we are the real parent, this is a race
- * inside ptrace_attach. It is waiting for the tasklist_lock,
- * which we have to switch the parent links, but has already set
- * the flags in p->ptrace.
- */
- return (p->parent != p->real_parent);
-}
-
static long do_wait(pid_t pid, int options, struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
int ret;
list_for_each(_p,&tsk->children) {
- p = list_entry(_p,struct task_struct,sibling);
+ p = list_entry(_p, struct task_struct, sibling);
ret = eligible_child(pid, options, p);
if (!ret)
switch (p->state) {
case TASK_TRACED:
- /*
- * When we hit the race with PTRACE_ATTACH,
- * we will not report this child. But the
- * race means it has not yet been moved to
- * our ptrace_children list, so we need to
- * set the flag here to avoid a spurious ECHILD
- * when the race happens with the only child.
- */
flag = 1;
- if (!my_ptrace_child(p))
- continue;
- /*FALLTHROUGH*/
+ continue;
case TASK_STOPPED:
/*
* It's stopped now, so it might later
* continue, exit, or stop again.
*/
flag = 1;
- if (!(options & WUNTRACED) &&
- !my_ptrace_child(p))
+ if (!(options & WUNTRACED))
+ continue;
+ if (tracehook_inhibit_wait_stopped(p))
continue;
retval = wait_task_stopped(p, ret == 2,
(options & WNOWAIT),
goto check_continued;
if (!likely(options & WEXITED))
continue;
+ if (tracehook_inhibit_wait_zombie(p)) {
+ flag = 1;
+ continue;
+ }
retval = wait_task_zombie(
p, (options & WNOWAIT),
infop, stat_addr, ru);
flag = 1;
if (!unlikely(options & WCONTINUED))
continue;
+ if (tracehook_inhibit_wait_continued(p))
+ continue;
retval = wait_task_continued(
p, (options & WNOWAIT),
infop, stat_addr, ru);
break;
}
}
- if (!flag) {
- list_for_each(_p, &tsk->ptrace_children) {
- p = list_entry(_p, struct task_struct,
- ptrace_list);
- if (!eligible_child(pid, options, p))
- continue;
- flag = 1;
- break;
- }
+
+ retval = ptrace_do_wait(tsk, pid, options,
+ infop, stat_addr, ru);
+ if (retval != -ECHILD) {
+ flag = 1;
+ if (retval != 0) /* He released the lock. */
+ goto end;
}
+
if (options & __WNOTHREAD)
break;
tsk = next_thread(tsk);
- if (tsk->signal != current->signal)
- BUG();
+ BUG_ON(tsk->signal != current->signal);
} while (tsk != current);
read_unlock(&tasklist_lock);
remove_wait_queue(¤t->signal->wait_chldexit,&wait);
if (infop) {
if (retval > 0)
- retval = 0;
+ retval = 0;
else {
/*
* For a WNOHANG return, clear out all the fields
git://git.onelab.eu / linux-2.6.git / blobdiff