[PATCH 13/13] mm: enlarge the int parameter of update_lru_size()

[Yu Zhao <yuzhao@google.com>]

In update_lru_sizes(), we call update_lru_size() with a long
argument, whereas the callee only takes an int parameter. Though this
isn't causing any overflow I'm aware of, it's not a good idea to
go through the truncation since the underlying counters are already
in long.

This patch enlarges all relevant parameters on the path to the final
underlying counters:
	update_lru_size(int -> long)
		if memcg:
			__mod_lruvec_state(int -> long)
				if smp:
					__mod_node_page_state(long)
				else:
					__mod_node_page_state(int -> long)
			__mod_memcg_lruvec_state(int -> long)
				__mod_memcg_state(int -> long)
		else:
			__mod_lruvec_state(int -> long)
				if smp:
					__mod_node_page_state(long)
				else:
					__mod_node_page_state(int -> long)

		__mod_zone_page_state(long)

		if memcg:
			mem_cgroup_update_lru_size(int -> long)

Note that __mod_node_page_state() for the smp case and
__mod_zone_page_state() already use long. So this change also fixes
the inconsistency.

Signed-off-by: Yu Zhao <yuzhao@google.com>
---
 include/linux/memcontrol.h | 14 +++++++-------
 include/linux/mm_inline.h  |  2 +-
 include/linux/vmstat.h     |  2 +-
 mm/memcontrol.c            | 10 +++++-----
 4 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index d0b036123c6a..fcd1829f8382 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -621,7 +621,7 @@ static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
 int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
 
 void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
-		int zid, int nr_pages);
+		int zid, long nr_pages);
 
 static inline
 unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
@@ -707,7 +707,7 @@ static inline unsigned long memcg_page_state_local(struct mem_cgroup *memcg,
 	return x;
 }
 
-void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val);
+void __mod_memcg_state(struct mem_cgroup *memcg, int idx, long val);
 
 /* idx can be of type enum memcg_stat_item or node_stat_item */
 static inline void mod_memcg_state(struct mem_cgroup *memcg,
@@ -790,9 +790,9 @@ static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec,
 }
 
 void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
-			      int val);
+			      long val);
 void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
-			int val);
+			long val);
 void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val);
 
 void mod_memcg_obj_state(void *p, int idx, int val);
@@ -1166,7 +1166,7 @@ static inline unsigned long memcg_page_state_local(struct mem_cgroup *memcg,
 
 static inline void __mod_memcg_state(struct mem_cgroup *memcg,
 				     int idx,
-				     int nr)
+				     long nr)
 {
 }
 
@@ -1201,12 +1201,12 @@ static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec,
 }
 
 static inline void __mod_memcg_lruvec_state(struct lruvec *lruvec,
-					    enum node_stat_item idx, int val)
+					    enum node_stat_item idx, long val)
 {
 }
 
 static inline void __mod_lruvec_state(struct lruvec *lruvec,
-				      enum node_stat_item idx, int val)
+				      enum node_stat_item idx, long val)
 {
 	__mod_node_page_state(lruvec_pgdat(lruvec), idx, val);
 }
diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h
index 355ea1ee32bd..18e85071b44a 100644
--- a/include/linux/mm_inline.h
+++ b/include/linux/mm_inline.h
@@ -26,7 +26,7 @@ static inline int page_is_file_lru(struct page *page)
 
 static __always_inline void update_lru_size(struct lruvec *lruvec,
 				enum lru_list lru, enum zone_type zid,
-				int nr_pages)
+				long nr_pages)
 {
 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
 
diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index 91220ace31da..2ae35e8c45f0 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -310,7 +310,7 @@ static inline void __mod_zone_page_state(struct zone *zone,
 }
 
 static inline void __mod_node_page_state(struct pglist_data *pgdat,
-			enum node_stat_item item, int delta)
+			enum node_stat_item item, long delta)
 {
 	node_page_state_add(delta, pgdat, item);
 }
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index cfa6cbad21d5..11bc4bb36882 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -774,7 +774,7 @@ mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz)
  * @idx: the stat item - can be enum memcg_stat_item or enum node_stat_item
  * @val: delta to add to the counter, can be negative
  */
-void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val)
+void __mod_memcg_state(struct mem_cgroup *memcg, int idx, long val)
 {
 	long x, threshold = MEMCG_CHARGE_BATCH;
 
@@ -812,7 +812,7 @@ parent_nodeinfo(struct mem_cgroup_per_node *pn, int nid)
 }
 
 void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
-			      int val)
+			      long val)
 {
 	struct mem_cgroup_per_node *pn;
 	struct mem_cgroup *memcg;
@@ -853,7 +853,7 @@ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
  * change of state at this level: per-node, per-cgroup, per-lruvec.
  */
 void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
-			int val)
+			long val)
 {
 	/* Update node */
 	__mod_node_page_state(lruvec_pgdat(lruvec), idx, val);
@@ -1354,7 +1354,7 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgd
  * so as to allow it to check that lru_size 0 is consistent with list_empty).
  */
 void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
-				int zid, int nr_pages)
+				int zid, long nr_pages)
 {
 	struct mem_cgroup_per_node *mz;
 	unsigned long *lru_size;
@@ -1371,7 +1371,7 @@ void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
 
 	size = *lru_size;
 	if (WARN_ONCE(size < 0,
-		"%s(%p, %d, %d): lru_size %ld\n",
+		"%s(%p, %d, %ld): lru_size %ld\n",
 		__func__, lruvec, lru, nr_pages, size)) {
 		VM_BUG_ON(1);
 		*lru_size = 0;
-- 
2.28.0.681.g6f77f65b4e-goog