On Fri, May 04, 2012 at 07:08:38AM +1000, NeilBrown (neilb@suse.de) wrote:
> You can only check the owner on SMP builds, or when debugging is enabled.
> So I don't think that approach can work.

You can store owner in master device and protect with mutex itself.
On non-smp systems it can not be preempted, so can be checked without
mutex.

-- 
	Evgeniy Polyakov