mm/memcg: apply add/del_page to lruvec

Take lruvec further: pass it instead of zone to add_page_to_lru_list() and
del_page_from_lru_list(); and pagevec_lru_move_fn() pass lruvec down to
its target functions.

This cleanup eliminates a swathe of cruft in memcontrol.c, including
mem_cgroup_lru_add_list(), mem_cgroup_lru_del_list() and
mem_cgroup_lru_move_lists() - which never actually touched the lists.

In their place, mem_cgroup_page_lruvec() to decide the lruvec, previously
a side-effect of add, and mem_cgroup_update_lru_size() to maintain the
lru_size stats.

Whilst these are simplifications in their own right, the goal is to bring
the evaluation of lruvec next to the spin_locking of the lrus, in
preparation for a future patch.

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 19 insertions, 37 deletions

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 609ef7c..83e7ba9 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -63,11 +63,7 @@ extern int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
 					gfp_t gfp_mask);
 
 struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
-struct lruvec *mem_cgroup_lru_add_list(struct zone *, struct page *,
-				       enum lru_list);
-void mem_cgroup_lru_del_list(struct page *, enum lru_list);
-struct lruvec *mem_cgroup_lru_move_lists(struct zone *, struct page *,
-					 enum lru_list, enum lru_list);
+struct lruvec *mem_cgroup_page_lruvec(struct page *, struct zone *);
 
 /* For coalescing uncharge for reducing memcg' overhead*/
 extern void mem_cgroup_uncharge_start(void);
@@ -122,8 +118,7 @@ int mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec);
 int mem_cgroup_inactive_file_is_low(struct lruvec *lruvec);
 int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
 unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list);
-struct zone_reclaim_stat*
-mem_cgroup_get_reclaim_stat_from_page(struct page *page);
+void mem_cgroup_update_lru_size(struct lruvec *, enum lru_list, int);
 extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
 					struct task_struct *p);
 extern void mem_cgroup_replace_page_cache(struct page *oldpage,
@@ -250,21 +245,8 @@ static inline struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone,
 	return &zone->lruvec;
 }
 
-static inline struct lruvec *mem_cgroup_lru_add_list(struct zone *zone,
-						     struct page *page,
-						     enum lru_list lru)
-{
-	return &zone->lruvec;
-}
-
-static inline void mem_cgroup_lru_del_list(struct page *page, enum lru_list lru)
-{
-}
-
-static inline struct lruvec *mem_cgroup_lru_move_lists(struct zone *zone,
-						       struct page *page,
-						       enum lru_list from,
-						       enum lru_list to)
+static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
+						    struct zone *zone)
 {
 	return &zone->lruvec;
 }
@@ -345,10 +327,10 @@ mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
 	return 0;
 }
 
-static inline struct zone_reclaim_stat*
-mem_cgroup_get_reclaim_stat_from_page(struct page *page)
+static inline void
+mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
+			      int increment)
 {
-	return NULL;
 }
 
 static inline void
diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h
index 16d45d9..1397ccf 100644
--- a/include/linux/mm_inline.h
+++ b/include/linux/mm_inline.h
@@ -21,22 +21,22 @@ static inline int page_is_file_cache(struct page *page)
 	return !PageSwapBacked(page);
 }
 
-static __always_inline void
-add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list lru)
+static __always_inline void add_page_to_lru_list(struct page *page,
+				struct lruvec *lruvec, enum lru_list lru)
 {
-	struct lruvec *lruvec;
-
-	lruvec = mem_cgroup_lru_add_list(zone, page, lru);
+	int nr_pages = hpage_nr_pages(page);
+	mem_cgroup_update_lru_size(lruvec, lru, nr_pages);
 	list_add(&page->lru, &lruvec->lists[lru]);
-	__mod_zone_page_state(zone, NR_LRU_BASE + lru, hpage_nr_pages(page));
+	__mod_zone_page_state(lruvec_zone(lruvec), NR_LRU_BASE + lru, nr_pages);
 }
 
-static __always_inline void
-del_page_from_lru_list(struct zone *zone, struct page *page, enum lru_list lru)
+static __always_inline void del_page_from_lru_list(struct page *page,
+				struct lruvec *lruvec, enum lru_list lru)
 {
-	mem_cgroup_lru_del_list(page, lru);
+	int nr_pages = hpage_nr_pages(page);
+	mem_cgroup_update_lru_size(lruvec, lru, -nr_pages);
 	list_del(&page->lru);
-	__mod_zone_page_state(zone, NR_LRU_BASE + lru, -hpage_nr_pages(page));
+	__mod_zone_page_state(lruvec_zone(lruvec), NR_LRU_BASE + lru, -nr_pages);
 }
 
 /**
diff --git a/include/linux/swap.h b/include/linux/swap.h
index ff38eb7..b666193 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -221,8 +221,8 @@ extern unsigned int nr_free_pagecache_pages(void);
 /* linux/mm/swap.c */
 extern void __lru_cache_add(struct page *, enum lru_list lru);
 extern void lru_cache_add_lru(struct page *, enum lru_list lru);
-extern void lru_add_page_tail(struct zone* zone,
-			      struct page *page, struct page *page_tail);
+extern void lru_add_page_tail(struct page *page, struct page *page_tail,
+			      struct lruvec *lruvec);
 extern void activate_page(struct page *);
 extern void mark_page_accessed(struct page *);
 extern void lru_add_drain(void);