movement, either.  Already, in commit 5343daceec, KOSAKI did it about
shrink_inactive_list.

This patch removes unnecessary overhead of page accounting and locking in
shrink_active_list as follow-up work of commit 5343daceec.
Signed-off-by: Vincent Li <macli@brc.ubc.ca>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>