do_wait: kill the old BUG_ON, use while_each_thread()

do_wait() does BUG_ON(tsk->signal != current->signal), this looks like a
raher obsolete check.  At least, I don't think do_wait() is the best place
to verify that all threads have the same ->signal.  Remove it.

Also, change the code to use while_each_thread().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
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, 3 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 9c6881a0a8b4..dd83c8419101 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1595,9 +1595,7 @@ repeat:
 
                 if (wo->wo_flags & __WNOTHREAD)
                         break;
-                tsk = next_thread(tsk);
-                BUG_ON(tsk->signal != current->signal);
-        } while (tsk != current);
+        } while_each_thread(current, tsk);
         read_unlock(&tasklist_lock);
 
 notask: