Re: [PATCH mm-unstable 8/8] mm/hugetlb: convert demote_free_huge_page to folios

[Sidhartha Kumar]

On 1/9/23 2:01 PM, John Hubbard wrote:
> On 1/9/23 10:23, Mike Kravetz wrote:
> > > > > > No problems with the code, but I am not in love with the name 
> > > > > > subfolio.
> > > > > > I know it is patterned after 'subpage'.  For better or worse, the 
> > > > > > term
> > > > > > subpage is used throughout the kernel.  This would be the first 
> > > > > > usage of
> > > > > > the term 'subfolio'.
> > > > > >
> > > > > > Matthew do you have any comments on the naming?  It is local to 
> > > > > > hugetlb,
> > > > > > but I would hate to see use of the term subfolio based on its 
> > > > > > introduction
> > > > > > here.
> > > > >
> > > > > I'm really not a fan of it either.  I intended to dive into this patch
> > > > > and understand the function it's modifying, in the hopes of suggesting
> > > > > a better name and/or method.
> > > >
> > > > At a high level, this routine is splitting a very large folio (1G for
> > > > example) into multiple large folios of a smaller size (512 2M folios 
> > > > for
> > > > example).  The loop is iterating through the very large folio at
> > > > increments of the smaller large folio.  subfolio (previously 
> > > > subpage) is
> > > > used to point to the smaller large folio within the loop.
> > > If folio does not need to be part of the variable name, how about 
> > > something
> > > like 'demote_target'? The prep call inside the loop would then look 
> > > like:
> > >
> > > prep_new_hugetlb_folio(target_hstate, demote_target, nid);
> > >
> > > so it is still clear that demote_target is a folio. A more concise 
> > > version
> > > could also be 'demote_dst' but that seems more ambiguous than target.
> >
> > I am OK with that naming.  Primary concern was the introduction of the
> > term subfolio.
>
> How about one of these:
>
>      smaller_folio
>      inner_folio
>
> Those are more self-explanatory, while still avoiding "subfolio".
I would be fine with inner_folio.

Thanks,
Sidhartha Kumar

> thanks,