From e841cc9cb0a7e9ccdab087a5c983066e0e06757f Mon Sep 17 00:00:00 2001
From: Alex Shi <alex.shi@linux.alibaba.com>
Date: Wed, 7 Jul 2021 10:17:29 +0800
Subject: [PATCH] mm/vmscan: remove lruvec reget in move_pages_to_lru
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

mainline inclusion
from mainline-v5.11-rc1
commit afca9157fd426451eb182c9de4bfe4b9382a873a
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I3ZF7C?from=project-issue
CVE: NA

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

Isolated page shouldn't be recharged by memcg since the memcg migration
isn't possible at the time.  All pages were isolated from the same lruvec
(and isolation inhibits memcg migration).  So remove unnecessary
regetting.

Thanks to Alexander Duyck for pointing this out.

Link: https://lkml.kernel.org/r/1604566549-62481-12-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: "Chen, Rong A" <rong.a.chen@intel.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mika Penttilä <mika.penttila@nextfour.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Reviewed-by: chenwandun <chenwandun@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
---
 mm/vmscan.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index e366ac953d38..8e6dfc5386c9 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1890,7 +1890,12 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
 			continue;
 		}
 
-		lruvec = mem_cgroup_page_lruvec(page, pgdat);
+		/*
+		 * All pages were isolated from the same lruvec (and isolation
+		 * inhibits memcg migration).
+		 */
+		VM_BUG_ON_PAGE(mem_cgroup_page_lruvec(page, page_pgdat(page))
+							!= lruvec, page);
 		lru = page_lru(page);
 		nr_pages = thp_nr_pages(page);
 
-- 
GitLab