signals: do_group_exit(): use signal_group_exit() more consistently

do_group_exit() checks SIGNAL_GROUP_EXIT to avoid taking sighand->siglock.
Since ed5d2cac114202fe2978a9cbcab8f5032796d538 exec() doesn't set this
flag, we should use signal_group_exit().

This is not needed for correctness, but can speedup the multithreaded exec
and makes the code more consistent.

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>

1 files changed, 4 insertions, 3 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index ae0f2c4e452..6d019aa8522 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1115,12 +1115,13 @@ asmlinkage long sys_exit(int error_code)
 NORET_TYPE void
 do_group_exit(int exit_code)
 {
+        struct signal_struct *sig = current->signal;
+
         BUG_ON(exit_code & 0x80); /* core dumps don't get here */
 
-        if (current->signal->flags & SIGNAL_GROUP_EXIT)
-                exit_code = current->signal->group_exit_code;
+        if (signal_group_exit(sig))
+                exit_code = sig->group_exit_code;
         else if (!thread_group_empty(current)) {
-                struct signal_struct *const sig = current->signal;
                 struct sighand_struct *const sighand = current->sighand;
                 spin_lock_irq(&sighand->siglock);
                 if (signal_group_exit(sig))