Re: [PATCH mm-unstable 3/8] mm/hugetlb: convert dequeue_hugetlb_page_node functions to folios

[Matthew Wilcox]

On Tue, Jan 03, 2023 at 01:13:35PM -0600, Sidhartha Kumar wrote:
> +static struct folio *dequeue_hugetlb_folio_node_exact(struct hstate *h,
> +								int nid)
>  {
>  	struct page *page;
> +	struct folio *folio;
>  	bool pin = !!(current->flags & PF_MEMALLOC_PIN);
>  
>  	lockdep_assert_held(&hugetlb_lock);
>  	list_for_each_entry(page, &h->hugepage_freelists[nid], lru) {
> -		if (pin && !is_longterm_pinnable_page(page))
> +		folio = page_folio(page);

I'd argue that you can pull folios directly off the hugepage_freelists.
Since they're attached through the 'lru', you know they're not tail
pages, because lru.prev aliases with compound_head.

The rest looks good.