Re: [RFC PATCH 4/4] mm, hugetlb, soft_offline: use new_page_nodemask for soft offline migration

From: Vlastimil Babka
Date: Wed Jun 14 2017 - 12:23:12 EST


On 06/13/2017 11:00 AM, Michal Hocko wrote:
> From: Michal Hocko <mhocko@xxxxxxxx>
>
> new_page is yet another duplication of the migration callback which has
> to handle hugetlb migration specially. We can safely use the generic
> new_page_nodemask for the same purpose.
>
> Please note that gigantic hugetlb pages do not need any special handling
> because alloc_huge_page_nodemask will make sure to check pages in all
> per node pools. The reason this was done previously was that
> alloc_huge_page_node treated NO_NUMA_NODE and a specific node
> differently and so alloc_huge_page_node(nid) would check on this
> specific node.
>
> Noticed-by: Vlastimil Babka <vbabka@xxxxxxx>
> Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>

Acked-by: Vlastimil Babka <vbabka@xxxxxxx>

> ---
> mm/memory-failure.c | 10 +---------
> 1 file changed, 1 insertion(+), 9 deletions(-)
>
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index 3615bffbd269..7040f60ecb71 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -1487,16 +1487,8 @@ EXPORT_SYMBOL(unpoison_memory);
> static struct page *new_page(struct page *p, unsigned long private, int **x)
> {
> int nid = page_to_nid(p);
> - if (PageHuge(p)) {
> - struct hstate *hstate = page_hstate(compound_head(p));
>
> - if (hstate_is_gigantic(hstate))
> - return alloc_huge_page_node(hstate, NUMA_NO_NODE);
> -
> - return alloc_huge_page_node(hstate, nid);
> - } else {
> - return __alloc_pages_node(nid, GFP_HIGHUSER_MOVABLE, 0);
> - }
> + return new_page_nodemask(p, nid, &node_states[N_MEMORY]);
> }
>
> /*
>