Re: [PATCH 11/11] afs: Fix dirty-region encoding on ppc32 with 64K pages

From: David Howells
Date: Wed Oct 28 2020 - 18:07:23 EST


Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:

> > +{
> > + if (PAGE_SIZE - 1 <= __AFS_PAGE_PRIV_MASK)
> > + return 1;
> > + else
> > + return PAGE_SIZE / (__AFS_PAGE_PRIV_MASK + 1);
>
> Could this be DIV_ROUND_UP(PAGE_SIZE, __AFS_PAGE_PRIV_MASK + 1); avoiding
> a conditional? I appreciate it's calculated at compile time today, but
> it'll be dynamic with THP.

Hmmm - actually, I want a shift size, not a number of bytes as I divide by it
twice in afs_page_dirty().

David