Re: [PATCH] mm/hugetlb: Convert &folio->page to folio_page(folio, 0)

[Matthew Wilcox]

On Wed, Apr 09, 2025 at 03:07:50PM -0700, Fan Ni wrote:
> On Wed, Apr 09, 2025 at 04:15:30AM +0100, Matthew Wilcox wrote:
> > >  		 */
> > > -		free_page_and_swap_cache(&new_folio->page);
> > > +		free_page_and_swap_cache(folio_page(new_folio, 0));
> > >  	}
> > 
> > free_page_and_swap_cache() should be converted to be
> > free_folio_and_swap_cache().
> 
> While looking into this function, I see it is defined as a macro in
> swap.h as below,
> #define free_page_and_swap_cache(page) \
>         put_page(page) 
> 
> While checking put_page() in include/linux.mm.h, it always converts page
> to folio, is there a reason why we do not take "folio" directly?

There are a lot of places to convert!

$ git grep '[^a-zA-Z_>]put_page(' |wc -l
472

... and that's after four years of doing folio conversions.

free_folio_and_swap_cache() should call folio_put() in the !CONFIG_SWAP
case.