lkml.org 
[lkml]   [2011]   [Jun]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 2/8] kill tracehook_notify_death()
Kill tracehook_notify_death(), reimplement the logic in its caller,
exit_notify().

This also fixes a minor bug, if the exiting task is the group_leader
and it is traced by its real_parent, tracehook_notify_death() returns
task->exit_signal or SIGCHLD depending on thread_group_empty(), this
looks strange.

Also, change the exec_id check to use thread_group_leader() instead
of task_detached(), this looks more clear.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---

include/linux/tracehook.h | 34 ----------------------------------
kernel/exit.c | 19 +++++++++++--------
2 files changed, 11 insertions(+), 42 deletions(-)

--- ptrace/include/linux/tracehook.h~2_kill_notify_death 2011-06-22 22:47:04.000000000 +0200
+++ ptrace/include/linux/tracehook.h 2011-06-22 22:47:11.000000000 +0200
@@ -152,40 +152,6 @@ static inline void tracehook_signal_hand
ptrace_notify(SIGTRAP);
}

-#define DEATH_REAP -1
-#define DEATH_DELAYED_GROUP_LEADER -2
-
-/**
- * tracehook_notify_death - task is dead, ready to notify parent
- * @task: @current task now exiting
- * @death_cookie: value to pass to tracehook_report_death()
- * @group_dead: nonzero if this was the last thread in the group to die
- *
- * A return value >= 0 means call do_notify_parent() with that signal
- * number. Negative return value can be %DEATH_REAP to self-reap right
- * now, or %DEATH_DELAYED_GROUP_LEADER to a zombie without notifying our
- * parent. Note that a return value of 0 means a do_notify_parent() call
- * that sends no signal, but still wakes up a parent blocked in wait*().
- *
- * Called with write_lock_irq(&tasklist_lock) held.
- */
-static inline int tracehook_notify_death(struct task_struct *task,
- void **death_cookie, int group_dead)
-{
- if (task_detached(task))
- return task->ptrace ? SIGCHLD : DEATH_REAP;
-
- /*
- * 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 (thread_group_empty(task) && !ptrace_reparented(task))
- return task->exit_signal;
-
- return task->ptrace ? SIGCHLD : DEATH_DELAYED_GROUP_LEADER;
-}
-
#ifdef TIF_NOTIFY_RESUME
/**
* set_notify_resume - cause tracehook_notify_resume() to be called
--- ptrace/kernel/exit.c~2_kill_notify_death 2011-06-22 22:47:11.000000000 +0200
+++ ptrace/kernel/exit.c 2011-06-22 22:47:11.000000000 +0200
@@ -818,9 +818,7 @@ static void forget_original_parent(struc
*/
static void exit_notify(struct task_struct *tsk, int group_dead)
{
- int signal;
bool autoreap;
- void *cookie;

/*
* This does two things:
@@ -851,16 +849,21 @@ static void exit_notify(struct task_stru
* we have changed execution domain as these two values started
* the same after a fork.
*/
- if (tsk->exit_signal != SIGCHLD && !task_detached(tsk) &&
+ if (thread_group_leader(tsk) && tsk->exit_signal != SIGCHLD &&
(tsk->parent_exec_id != tsk->real_parent->self_exec_id ||
tsk->self_exec_id != tsk->parent_exec_id))
tsk->exit_signal = SIGCHLD;

- signal = tracehook_notify_death(tsk, &cookie, group_dead);
- if (signal >= 0)
- autoreap = do_notify_parent(tsk, signal);
- else
- autoreap = (signal == DEATH_REAP);
+ if (unlikely(tsk->ptrace)) {
+ int sig = thread_group_leader(tsk) && !ptrace_reparented(tsk)
+ ? tsk->exit_signal : SIGCHLD;
+ autoreap = do_notify_parent(tsk, sig);
+ } else if (thread_group_leader(tsk)) {
+ autoreap = thread_group_empty(tsk) &&
+ do_notify_parent(tsk, tsk->exit_signal);
+ } else {
+ autoreap = true;
+ }

tsk->exit_state = autoreap ? EXIT_DEAD : EXIT_ZOMBIE;



\
 
 \ /
  Last update: 2011-06-22 23:13    [W:0.133 / U:0.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site