[PATCH] cfq-iosched: Detect hardware queueing

If the hardware is doing real queueing, decide that it's worthless to
idle the hardware. It does reasonable simultaneous io in that case
anyways, and the idling hurts some work loads.

Signed-off-by: Jens Axboe <axboe@suse.de>

diff --cc block/cfq-iosched.c
Simple merge