Re: [PATCH v14 084/138] mm/page_alloc: Add folio allocation functions
From: David Howells
Date: Tue Aug 10 2021 - 17:51:31 EST
Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> wrote:
> +struct folio *folio_alloc(gfp_t gfp, unsigned order)
> +{
> + struct page *page = alloc_pages(gfp | __GFP_COMP, order);
> +
> + if (page && order > 1)
> + prep_transhuge_page(page);
Ummm... Shouldn't order==1 pages (two page folios) be prep'd also?
> + return (struct folio *)page;
> +}
Would it be better to just jump to alloc_pages() if order <= 1? E.g.:
struct folio *folio_alloc(gfp_t gfp, unsigned order)
{
struct page *page;
if (order <= 1)
return (struct folio *)alloc_pages(gfp | __GFP_COMP, order);
page = alloc_pages(gfp | __GFP_COMP, order);
if (page)
prep_transhuge_page(page);
return (struct folio *)page;
}
David