Re: [PATCH v2 1/2] mm, thp: introduce dedicated transparent huge page allocation interfaces

[Christopher Lameter <cl@linux.com>]

On Fri, 20 Oct 2017, changbin.du@intel.com wrote:

> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 269b5df..2a960fc 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -501,6 +501,43 @@ void prep_transhuge_page(struct page *page)
>  	set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR);
>  }
>
> +struct page *alloc_transhuge_page_vma(gfp_t gfp_mask,
> +		struct vm_area_struct *vma, unsigned long addr)
> +{
> +	struct page *page;
> +
> +	page = alloc_pages_vma(gfp_mask | __GFP_COMP, HPAGE_PMD_ORDER,
> +			       vma, addr, numa_node_id(), true);
> +	if (unlikely(!page))
> +		return NULL;
> +	prep_transhuge_page(page);
> +	return page;
> +}
> +
> +struct page *alloc_transhuge_page_nodemask(gfp_t gfp_mask,
> +		int preferred_nid, nodemask_t *nmask)
> +{
> +	struct page *page;
> +
> +	page = __alloc_pages_nodemask(gfp_mask | __GFP_COMP, HPAGE_PMD_ORDER,
> +				      preferred_nid, nmask);
> +	if (unlikely(!page))
> +		return NULL;
> +	prep_transhuge_page(page);
> +	return page;
> +}
> +
> +struct page *alloc_transhuge_page(gfp_t gfp_mask)
> +{
> +	struct page *page;
> +
> +	page = alloc_pages(gfp_mask | __GFP_COMP, HPAGE_PMD_ORDER);
> +	if (unlikely(!page))
> +		return NULL;
> +	prep_transhuge_page(page);
> +	return page;
> +}
> +

These look pretty similar to the code used for huge pages (aside from the
call to prep_transhuge_page(). Maybe we can have common allocation
primitives for huge pages?