mm: memcontrol: prepare move_account for removal of private page type counters

When memcg uses the generic vmstat counters, it doesn't need to do
anything at charging and uncharging time.  It does, however, need to
migrate counts when pages move to a different cgroup in move_account.

Prepare the move_account function for the arrival of NR_FILE_PAGES,
NR_ANON_MAPPED, NR_ANON_THPS etc.  by having a branch for files and a
branch for anon, which can then divided into sub-branches.

Signed-off-by: Johannes Weiner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Alex Shi <[email protected]>
Reviewed-by: Joonsoo Kim <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Shakeel Butt <[email protected]>
Cc: Balbir Singh <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 13 insertions, 12 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ff45bef46ffe..f82ae3723760 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5434,7 +5434,6 @@ static int mem_cgroup_move_account(struct page *page,
 	struct pglist_data *pgdat;
 	unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
 	int ret;
-	bool anon;
 
 	VM_BUG_ON(from == to);
 	VM_BUG_ON_PAGE(PageLRU(page), page);
@@ -5452,25 +5451,27 @@ static int mem_cgroup_move_account(struct page *page,
 	if (page->mem_cgroup != from)
 		goto out_unlock;
 
-	anon = PageAnon(page);
-
 	pgdat = page_pgdat(page);
 	from_vec = mem_cgroup_lruvec(from, pgdat);
 	to_vec = mem_cgroup_lruvec(to, pgdat);
 
 	lock_page_memcg(page);
 
-	if (!anon && page_mapped(page)) {
-		__mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages);
-		__mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages);
-	}
+	if (!PageAnon(page)) {
+		if (page_mapped(page)) {
+			__mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages);
+			__mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages);
+		}
 
-	if (!anon && PageDirty(page)) {
-		struct address_space *mapping = page_mapping(page);
+		if (PageDirty(page)) {
+			struct address_space *mapping = page_mapping(page);
 
-		if (mapping_cap_account_dirty(mapping)) {
-			__mod_lruvec_state(from_vec, NR_FILE_DIRTY, -nr_pages);
-			__mod_lruvec_state(to_vec, NR_FILE_DIRTY, nr_pages);
+			if (mapping_cap_account_dirty(mapping)) {
+				__mod_lruvec_state(from_vec, NR_FILE_DIRTY,
+						   -nr_pages);
+				__mod_lruvec_state(to_vec, NR_FILE_DIRTY,
+						   nr_pages);
+			}
 		}
 	}