Re: [RFC 1/8] mm: add overflow and underflow checks for page->_refcount

[Matthew Wilcox <willy@xxxxxxxxxxxxx>]

On Tue, Oct 26, 2021 at 09:21:29PM -0400, Pasha Tatashin wrote:
> I think we can do that by using:
> atomic_fetch_*() and check for overflow/underflow after operation. I
> will send the updated series soon.

Please include performance measurements.  You're adding code to some hot
paths.