No functional changes.

keyctl_session_to_parent() is the only user of signal->count which needs
the correct value.  Change it to use thread_group_empty() instead, this
must be strictly equivalent under tasklist, and imho looks better.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>