mm: memcontrol: kill mem_cgroup_nodeinfo()

No need to encapsulate a simple struct member access.

Link: https://lkml.kernel.org/r/20210209163304.77088-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/memcontrol.h

@@ -602,12 +602,6 @@ void mem_cgroup_uncharge_list(struct list_head *page_list);
 
 void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
 
-static struct mem_cgroup_per_node *
-mem_cgroup_nodeinfo(struct mem_cgroup *memcg, int nid)
-{
-	return memcg->nodeinfo[nid];
-}
-
 /**
  * mem_cgroup_lruvec - get the lru list vector for a memcg & node
  * @memcg: memcg of the wanted lruvec
@@ -631,7 +625,7 @@ static inline struct lruvec *mem_cgroup_lruvec(struct mem_cgroup *memcg,
 	if (!memcg)
 		memcg = root_mem_cgroup;
 
-	mz = mem_cgroup_nodeinfo(memcg, pgdat->node_id);
+	mz = memcg->nodeinfo[pgdat->node_id];
 	lruvec = &mz->lruvec;
 out:
 	/*

mm/memcontrol.c

@@ -414,13 +414,14 @@ static int memcg_expand_one_shrinker_map(struct mem_cgroup *memcg,
 					 int size, int old_size)
 {
 	struct memcg_shrinker_map *new, *old;
+	struct mem_cgroup_per_node *pn;
 	int nid;
 
 	lockdep_assert_held(&memcg_shrinker_map_mutex);
 
 	for_each_node(nid) {
-		old = rcu_dereference_protected(
-			mem_cgroup_nodeinfo(memcg, nid)->shrinker_map, true);
+		pn = memcg->nodeinfo[nid];
+		old = rcu_dereference_protected(pn->shrinker_map, true);
 		/* Not yet online memcg */
 		if (!old)
 			return 0;
@@ -433,7 +434,7 @@ static int memcg_expand_one_shrinker_map(struct mem_cgroup *memcg,
 		memset(new->map, (int)0xff, old_size);
 		memset((void *)new->map + old_size, 0, size - old_size);
 
-		rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_map, new);
+		rcu_assign_pointer(pn->shrinker_map, new);
 		call_rcu(&old->rcu, memcg_free_shrinker_map_rcu);
 	}
 
@@ -450,7 +451,7 @@ static void memcg_free_shrinker_maps(struct mem_cgroup *memcg)
 		return;
 
 	for_each_node(nid) {
-		pn = mem_cgroup_nodeinfo(memcg, nid);
+		pn = memcg->nodeinfo[nid];
 		map = rcu_dereference_protected(pn->shrinker_map, true);
 		kvfree(map);
 		rcu_assign_pointer(pn->shrinker_map, NULL);
@@ -713,7 +714,7 @@ static void mem_cgroup_remove_from_trees(struct mem_cgroup *memcg)
 	int nid;
 
 	for_each_node(nid) {
-		mz = mem_cgroup_nodeinfo(memcg, nid);
+		mz = memcg->nodeinfo[nid];
 		mctz = soft_limit_tree_node(nid);
 		if (mctz)
 			mem_cgroup_remove_exceeded(mz, mctz);
@@ -796,7 +797,7 @@ parent_nodeinfo(struct mem_cgroup_per_node *pn, int nid)
 	parent = parent_mem_cgroup(pn->memcg);
 	if (!parent)
 		return NULL;
-	return mem_cgroup_nodeinfo(parent, nid);
+	return parent->nodeinfo[nid];
 }
 
 void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
@@ -1136,7 +1137,7 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root,
 	if (reclaim) {
 		struct mem_cgroup_per_node *mz;
 
-		mz = mem_cgroup_nodeinfo(root, reclaim->pgdat->node_id);
+		mz = root->nodeinfo[reclaim->pgdat->node_id];
 		iter = &mz->iter;
 
 		if (prev && reclaim->generation != iter->generation)
@@ -1238,7 +1239,7 @@ static void __invalidate_reclaim_iterators(struct mem_cgroup *from,
 	int nid;
 
 	for_each_node(nid) {
-		mz = mem_cgroup_nodeinfo(from, nid);
+		mz = from->nodeinfo[nid];
 		iter = &mz->iter;
 		cmpxchg(&iter->position, dead_memcg, NULL);
 	}
@@ -2397,7 +2398,7 @@ static int memcg_hotplug_cpu_dead(unsigned int cpu)
 				struct mem_cgroup_per_node *pn;
 				long x;
 
-				pn = mem_cgroup_nodeinfo(memcg, nid);
+				pn = memcg->nodeinfo[nid];
 				lstatc = per_cpu_ptr(pn->lruvec_stat_cpu, cpu);
 
 				x = lstatc->count[i];
@@ -4098,7 +4099,7 @@ static int memcg_stat_show(struct seq_file *m, void *v)
 		unsigned long file_cost = 0;
 
 		for_each_online_pgdat(pgdat) {
-			mz = mem_cgroup_nodeinfo(memcg, pgdat->node_id);
+			mz = memcg->nodeinfo[pgdat->node_id];
 
 			anon_cost += mz->lruvec.anon_cost;
 			file_cost += mz->lruvec.file_cost;