> So it's basically dm calling into blk_unplug() all the time, which
> doesn't check if the queue is plugged. The reason why I didn't like the
> initial patch is that ->unplug_fn() really should not be called unless
> the queue IS plugged. So how about this instead:
>
>
http://git.kernel.dk/?p=linux-2.6-block.git;a=commit;h=c44993018887e82abd49023e92e8d8b...
>
> That's a lot more appropriate, imho.