[PATCH 1/2] mm: memcg: fix memcg file_dirty numa stat

From: Shakeel Butt <shakeelb@google.com>
To: Muchun Song <songmuchun@bytedance.com>,
	Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Roman Gushchin <guro@fb.com>,
	cgroups@vger.kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, Shakeel Butt <shakeelb@google.com>,
	stable@vger.kernel.org
Subject: [PATCH 1/2] mm: memcg: fix memcg file_dirty numa stat
Date: Sun, 27 Dec 2020 10:13:09 -0800	[thread overview]
Message-ID: <20201227181310.3235210-1-shakeelb@google.com> (raw)

The kernel updates the per-node NR_FILE_DIRTY stats on page migration
but not the memcg numa stats. That was not an issue until recently the
commit 5f9a4f4a7096 ("mm: memcontrol: add the missing numa_stat interface
for cgroup v2") exposed numa stats for the memcg. So fixing the
file_dirty per-memcg numa stat.

Fixes: 5f9a4f4a7096 ("mm: memcontrol: add the missing numa_stat interface for cgroup v2")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
---
 mm/migrate.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index ee5e612b4cd8..613794f6a433 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -500,9 +500,9 @@ int migrate_page_move_mapping(struct address_space *mapping,
 			__inc_lruvec_state(new_lruvec, NR_SHMEM);
 		}
 		if (dirty && mapping_can_writeback(mapping)) {
-			__dec_node_state(oldzone->zone_pgdat, NR_FILE_DIRTY);
+			__dec_lruvec_state(old_lruvec, NR_FILE_DIRTY);
 			__dec_zone_state(oldzone, NR_ZONE_WRITE_PENDING);
-			__inc_node_state(newzone->zone_pgdat, NR_FILE_DIRTY);
+			__inc_lruvec_state(new_lruvec, NR_FILE_DIRTY);
 			__inc_zone_state(newzone, NR_ZONE_WRITE_PENDING);
 		}
 	}
-- 
2.29.2.729.g45daf8777d-goog

