Commit 5af1ab1d authored by Miaohe Lin's avatar Miaohe Lin Committed by Linus Torvalds
Browse files

mm/hugetlb: optimize the surplus state transfer code in move_hugetlb_state() 

We should not transfer the per-node surplus state when we do not cross the
node in order to save some cpu cycles

Link: https://lkml.kernel.org/r/20210308112809.26107-3-linmiaohe@huawei.com


Signed-off-by: default avatarMiaohe Lin <linmiaohe@huawei.com>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 04adbc3f

mm/hugetlb.c

+6 −0
Original line number Diff line number Diff line
@@ -5682,6 +5682,12 @@ void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason) 
		SetHPageTemporary(oldpage);

		ClearHPageTemporary(newpage);



		/*

		 * There is no need to transfer the per-node surplus state

		 * when we do not cross the node.

		 */

		if (new_nid == old_nid)

			return;

		spin_lock(&hugetlb_lock);

		if (h->surplus_huge_pages_node[old_nid]) {

			h->surplus_huge_pages_node[old_nid]--;