Commit 65dff3b2 authored by Hugh Dickins's avatar Hugh Dickins Committed by Zheng Zengkai
Browse files

mm/memcg: fix 5.10 backport of splitting page memcg 



stable inclusion
from stable-5.10.27
commit 002ea848d7fd3bdcb6281e75bdde28095c2cd549
bugzilla: 51493

--------------------------------

The straight backport of 5.12's e1baddf8 ("mm/memcg: set memcg when
splitting page") works fine in 5.11, but turned out to be wrong for 5.10:
because that relies on a separate flag, which must also be set for the
memcg to be recognized and uncharged and cleared when freeing. Fix that.

Signed-off-by: default avatarHugh Dickins <hughd@google.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarChen Jun <chenjun102@huawei.com>
Acked-by: default avatar&nbsp; Weilong Chen <chenweilong@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent ab000ba0

mm/memcontrol.c

+5 −1
Original line number Diff line number Diff line
@@ -3274,13 +3274,17 @@ void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size) 
void split_page_memcg(struct page *head, unsigned int nr)

{

	struct mem_cgroup *memcg = head->mem_cgroup;

	int kmemcg = PageKmemcg(head);

	int i;



	if (mem_cgroup_disabled() || !memcg)

		return;



	for (i = 1; i < nr; i++)

	for (i = 1; i < nr; i++) {

		head[i].mem_cgroup = memcg;

		if (kmemcg)

			__SetPageKmemcg(head + i);

	}

	css_get_many(&memcg->css, nr - 1);

}