Re: [RFC PATCH 11/15] memremap: Add zone device access protection

[Peter Zijlstra]

On Tue, Jul 14, 2020 at 12:10:47PM -0700, Ira Weiny wrote:
> On Tue, Jul 14, 2020 at 10:40:57AM +0200, Peter Zijlstra wrote:

> > That's an anti-pattern vs static_keys, I'm thinking you actually want
> > static_key_slow_{inc,dec}() instead of {enable,disable}().
> 
> Thanks.  I'll go read the doc for those as I'm not familiar with them.

Look for static_branch_{inc,dec} in include/linux/jump_label.h, it
basically does the refcount thing you need and does the actual
transition on the 0->1 and 1->0 transitions.