signals: do_signal_stop(): use signal_group_exit()

do_signal_stop() needs signal_group_exit() but checks sig->group_exit_task.
 This (optimization) is correct, SIGNAL_STOP_DEQUEUED and SIGNAL_GROUP_EXIT
are mutually exclusive, but looks confusing.  Use signal_group_exit(), this
is not fastpath, the code clarity is more important.

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

diff --git a/kernel/signal.c b/kernel/signal.c
index fb8ffd4..29aca40 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1717,7 +1717,7 @@ static int do_signal_stop(int signr)
                struct task_struct *t;
 
                if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED) ||
-                   unlikely(sig->group_exit_task))
+                   unlikely(signal_group_exit(sig)))
                        return 0;
                /*
                 * There is no group stop already in progress.