make do_notify_parent() return bool

- change do_notify_parent() to return a boolean, true if the task should
  be reaped because its parent ignores SIGCHLD.

- update the only caller which checks the returned value, exit_notify().

This temporary uglifies exit_notify() even more, will be cleanuped by
the next change.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 87f7ca7..0df7231 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2145,7 +2145,7 @@ static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, s
        spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
 
        return ret;
-}      
+}
 
 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
                              sigset_t *mask);
@@ -2160,7 +2160,7 @@ extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_
 extern int kill_pgrp(struct pid *pid, int sig, int priv);
 extern int kill_pid(struct pid *pid, int sig, int priv);
 extern int kill_proc_info(int, struct siginfo *, pid_t);
-extern int do_notify_parent(struct task_struct *, int);
+extern bool do_notify_parent(struct task_struct *, int);
 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
 extern void force_sig(int, struct task_struct *);
 extern int send_sig(int, struct task_struct *, int);

diff --git a/kernel/exit.c b/kernel/exit.c
index d49134a..34d135f 100644 (file)
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -820,6 +820,7 @@ static void forget_original_parent(struct task_struct *father)
 static void exit_notify(struct task_struct *tsk, int group_dead)
 {
        int signal;
+       bool autoreap;
        void *cookie;
 
        /*
@@ -858,9 +859,11 @@ static void exit_notify(struct task_struct *tsk, int group_dead)
 
        signal = tracehook_notify_death(tsk, &cookie, group_dead);
        if (signal >= 0)
-               signal = do_notify_parent(tsk, signal);
+               autoreap = do_notify_parent(tsk, signal);
+       else
+               autoreap = (signal == DEATH_REAP);
 
-       tsk->exit_state = signal == DEATH_REAP ? EXIT_DEAD : EXIT_ZOMBIE;
+       tsk->exit_state = autoreap ? EXIT_DEAD : EXIT_ZOMBIE;
 
        /* mt-exec, de_thread() is waiting for group leader */
        if (unlikely(tsk->signal->notify_count < 0))
@@ -868,7 +871,7 @@ static void exit_notify(struct task_struct *tsk, int group_dead)
        write_unlock_irq(&tasklist_lock);
 
        /* If the process is dead, release it - nobody will wait for it */
-       if (signal == DEATH_REAP)
+       if (autoreap)
                release_task(tsk);
 }
 

diff --git a/kernel/signal.c b/kernel/signal.c
index 1550aee..d52e82c 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1577,15 +1577,15 @@ ret:
  * Let a parent know about the death of a child.
  * For a stopped/continued status change, use do_notify_parent_cldstop instead.
  *
- * Returns -1 if our parent ignored us and so we've switched to
- * self-reaping, or else @sig.
+ * Returns true if our parent ignored us and so we've switched to
+ * self-reaping.
  */
-int do_notify_parent(struct task_struct *tsk, int sig)
+bool do_notify_parent(struct task_struct *tsk, int sig)
 {
        struct siginfo info;
        unsigned long flags;
        struct sighand_struct *psig;
-       int ret = sig;
+       bool autoreap = false;
 
        BUG_ON(sig == -1);
 
@@ -1649,16 +1649,17 @@ int do_notify_parent(struct task_struct *tsk, int sig)
                 * is implementation-defined: we do (if you don't want
                 * it, just use SIG_IGN instead).
                 */
-               ret = tsk->exit_signal = -1;
+               autoreap = true;
+               tsk->exit_signal = -1;
                if (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN)
-                       sig = -1;
+                       sig = 0;
        }
-       if (valid_signal(sig) && sig > 0)
+       if (valid_signal(sig) && sig)
                __group_send_sig_info(sig, &info, tsk->parent);
        __wake_up_parent(tsk, tsk->parent);
        spin_unlock_irqrestore(&psig->siglock, flags);
 
-       return ret;
+       return autoreap;
 }
 
 /**