[PATCH] mm: memcontrol: Remove unused mod_memcg_obj_state()

[Muchun Song <songmuchun@xxxxxxxxxxxxx>]

Since commit:

  991e7673859e ("mm: memcontrol: account kernel stack per node")

There is no user of the mod_memcg_obj_state(). This patch just remove
it. Also rework type of the idx parameter of the mod_objcg_state()
from int to enum node_stat_item.

Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
 include/linux/memcontrol.h |  6 ------
 mm/memcontrol.c            | 11 -----------
 mm/slab.h                  |  4 ++--
 3 files changed, 2 insertions(+), 19 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index a1395b584947..d7e339bf72dc 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -795,8 +795,6 @@ void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
 			int 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);
-
 static inline void mod_lruvec_slab_state(void *p, enum node_stat_item idx,
 					 int val)
 {
@@ -1245,10 +1243,6 @@ static inline void mod_lruvec_slab_state(void *p, enum node_stat_item idx,
 	mod_node_page_state(page_pgdat(page), idx, val);
 }
 
-static inline void mod_memcg_obj_state(void *p, int idx, int val)
-{
-}
-
 static inline
 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
 					    gfp_t gfp_mask,
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 2124ded698b2..1337775b04f3 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -885,17 +885,6 @@ void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val)
 	rcu_read_unlock();
 }
 
-void mod_memcg_obj_state(void *p, int idx, int val)
-{
-	struct mem_cgroup *memcg;
-
-	rcu_read_lock();
-	memcg = mem_cgroup_from_obj(p);
-	if (memcg)
-		mod_memcg_state(memcg, idx, val);
-	rcu_read_unlock();
-}
-
 /**
  * __count_memcg_events - account VM events in a cgroup
  * @memcg: the memory cgroup
diff --git a/mm/slab.h b/mm/slab.h
index 4a24e1702923..725a0bb8b317 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -204,7 +204,7 @@ ssize_t slabinfo_write(struct file *file, const char __user *buffer,
 void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
 int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
 
-static inline int cache_vmstat_idx(struct kmem_cache *s)
+static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s)
 {
 	return (s->flags & SLAB_RECLAIM_ACCOUNT) ?
 		NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B;
@@ -294,7 +294,7 @@ static inline struct obj_cgroup *memcg_slab_pre_alloc_hook(struct kmem_cache *s,
 
 static inline void mod_objcg_state(struct obj_cgroup *objcg,
 				   struct pglist_data *pgdat,
-				   int idx, int nr)
+				   enum node_stat_item idx, int nr)
 {
 	struct mem_cgroup *memcg;
 	struct lruvec *lruvec;
-- 
2.20.1