Re: [PATCH 0/8] mm: globalize rest_of_page() macro

Peter Zijlstra
2026-03-04T12:48:18Z

On Tue, Mar 03, 2026 at 06:49:36PM -0800, Sean Christopherson wrote:
> On Tue, Mar 03, 2026, Jens Axboe wrote:
> > On 3/3/26 7:28 PM, Jakub Kicinski wrote:
> > > On Tue, 3 Mar 2026 20:27:08 -0500 Yury Norov wrote:
> > >> The net/9p networking driver has a handy macro to calculate the
> > >> amount of bytes from a given pointer to the end of page. Move it
> > >> to core/mm, and apply tree-wide. No functional changes intended.
> > >>
> > >> This series was originally introduced as a single patch #07/12 in:
> > >>
> > >> https://lore.kernel.org/all/20260219181407.290201-1-ynorov@nvidia.com/
> > >>
> > >> Split it for better granularity and submit separately.
> > >
> > > I don't get what the motivation is here. Another helper developers
> > > and readers of the code will need to know about just to replace
> > > obvious and easy to comprehend math.
> >
> > I fully agree, I had the same thought reading this.
>
> +1 from KVM-land.

Right, this. I hate these pointless helpers that obscure perfectly
sensible and obvious code -- and for me that includes things like
rounddown() and DIV_ROUND_UP().

It just makes the code harder to read.