signals: do_signal_stop: kill the SIGNAL_UNKILLABLE check

fae5fa44f1fd079ffbed8e0add929dd7bbd1347f changed do_signal_stop() to check
SIGNAL_UNKILLABLE, this wasn't needed.  If signal_group_exit() == F, the
signal sent to SIGNAL_UNKILLABLE task must be already filtered out by the
caller, get_signal_to_deliver().  And if signal_group_exit() == T we are
not going to stop.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 2 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index 15f901a26ec7..0514da573f22 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1649,8 +1649,7 @@ static int do_signal_stop(int signr)
         } else {
                 struct task_struct *t;
 
-                if (unlikely((sig->flags & (SIGNAL_STOP_DEQUEUED | SIGNAL_UNKILLABLE))
-                                         != SIGNAL_STOP_DEQUEUED) ||
+                if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED) ||
                     unlikely(signal_group_exit(sig)))
                         return 0;
                 /*