Re: New diagnostic routine - mutex_ownable()

[Taylor R Campbell <campbell+netbsd-tech-kern%mumble.net@localhost>]

> Date: Sun, 30 Apr 2017 13:36:12 +0000 (UTC)
> From: christos%astron.com@localhost (Christos Zoulas)
> 
> How frequently is this going to be used and what is the performance
> penalty for it. I am asking because I am running LOCKDEBUG all the time.

The idea is that it will be used unconditionally before potentially
low-probability conditional branches that acquire the lock.

So it may be appropriate to limit its use to KDASSERT, since it means
no-lock fast paths don't get to be no-lock fast paths.