kblockd: use flush_work

Switch the kblockd flushing from a global flush to a more specific
flush_work().

(akpm: bypassed maintainers, sorry.  There are other patches which depend on
this)

Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/block/as-iosched.c b/block/as-iosched.c
index 640aa83..109e91b 100644
--- a/block/as-iosched.c
+++ b/block/as-iosched.c
@@ -1306,7 +1306,7 @@
 	struct as_data *ad = e->elevator_data;
 
 	del_timer_sync(&ad->antic_timer);
-	kblockd_flush();
+	kblockd_flush_work(&ad->antic_work);
 
 	BUG_ON(!list_empty(&ad->fifo_list[REQ_SYNC]));
 	BUG_ON(!list_empty(&ad->fifo_list[REQ_ASYNC]));