[patch 16/26] mm/memcontrol: update lruvec counters in mem_cgroup_move_account

[akpm@linux-foundation.org]

From: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Subject: mm/memcontrol: update lruvec counters in mem_cgroup_move_account

Mapped, dirty and writeback pages are also counted in per-lruvec stats. 
These counters needs update when page is moved between cgroups.

Currently is nobody *consuming* the lruvec versions of these counters and
that there is no user-visible effect.

Link: http://lkml.kernel.org/r/157112699975.7360.1062614888388489788.stgit@buzz
Fixes: 00f3ca2c2d66 ("mm: memcontrol: per-lruvec stats infrastructure")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |   18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

--- a/mm/memcontrol.c~mm-memcontrol-update-lruvec-counters-in-mem_cgroup_move_account
+++ a/mm/memcontrol.c
@@ -5420,6 +5420,8 @@ static int mem_cgroup_move_account(struc
 				   struct mem_cgroup *from,
 				   struct mem_cgroup *to)
 {
+	struct lruvec *from_vec, *to_vec;
+	struct pglist_data *pgdat;
 	unsigned long flags;
 	unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
 	int ret;
@@ -5443,11 +5445,15 @@ static int mem_cgroup_move_account(struc
 
 	anon = PageAnon(page);
 
+	pgdat = page_pgdat(page);
+	from_vec = mem_cgroup_lruvec(pgdat, from);
+	to_vec = mem_cgroup_lruvec(pgdat, to);
+
 	spin_lock_irqsave(&from->move_lock, flags);
 
 	if (!anon && page_mapped(page)) {
-		__mod_memcg_state(from, NR_FILE_MAPPED, -nr_pages);
-		__mod_memcg_state(to, NR_FILE_MAPPED, nr_pages);
+		__mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages);
+		__mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages);
 	}
 
 	/*
@@ -5459,14 +5465,14 @@ static int mem_cgroup_move_account(struc
 		struct address_space *mapping = page_mapping(page);
 
 		if (mapping_cap_account_dirty(mapping)) {
-			__mod_memcg_state(from, NR_FILE_DIRTY, -nr_pages);
-			__mod_memcg_state(to, NR_FILE_DIRTY, nr_pages);
+			__mod_lruvec_state(from_vec, NR_FILE_DIRTY, -nr_pages);
+			__mod_lruvec_state(to_vec, NR_FILE_DIRTY, nr_pages);
 		}
 	}
 
 	if (PageWriteback(page)) {
-		__mod_memcg_state(from, NR_WRITEBACK, -nr_pages);
-		__mod_memcg_state(to, NR_WRITEBACK, nr_pages);
+		__mod_lruvec_state(from_vec, NR_WRITEBACK, -nr_pages);
+		__mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages);
 	}
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
_