Re: [PATCH] mm,hugetlb: Allocate frozen pages in alloc_buddy_hugetlb_folio

[Matthew Wilcox]

On Fri, Apr 11, 2025 at 03:44:31PM +0200, David Hildenbrand wrote:
> I assume htlb_alloc_mask() will always include _GFP_COMP.

static inline gfp_t htlb_alloc_mask(struct hstate *h)
{
        gfp_t gfp = __GFP_COMP | __GFP_NOWARN;

> But semantically, it might be wrong: __folio_alloc() will in the memdesc
> world also make sure to allocate the memdesc, __alloc_frozen_pages() not.
> 
> Maybe one would want a __alloc_frozen_folio() .... @willy?

This is fine.  Yes, it'll need to be modified when we get to the
separately allocated memdesc, but there's a number of places that
cast the freshly allocated page to a folio, and I'll have to come up
with a way to catch them all.

Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>

Oscar, if you want to take on the gigantic allocation next ...

 - I don't think we need folio_alloc_gigantic() to be wrapped in
   alloc_hooks
 - folio_alloc_gigantic() should return a frozen folio
 - as should hugetlb_cma_alloc_folio()