mm: memcontrol: use node page state naming scheme for memcg

The memory controllers stat function names are awkwardly long and
arbitrarily different from the zone and node stat functions.

The current interface is named:

  mem_cgroup_read_stat()
  mem_cgroup_update_stat()
  mem_cgroup_inc_stat()
  mem_cgroup_dec_stat()
  mem_cgroup_update_page_stat()
  mem_cgroup_inc_page_stat()
  mem_cgroup_dec_page_stat()

This patch renames it to match the corresponding node stat functions:

  memcg_page_state()		[node_page_state()]
  mod_memcg_state()		[mod_node_state()]
  inc_memcg_state()		[inc_node_state()]
  dec_memcg_state()		[dec_node_state()]
  mod_memcg_page_state()	[mod_node_page_state()]
  inc_memcg_page_state()	[inc_node_page_state()]
  dec_memcg_page_state()	[dec_node_page_state()]

Link: http://lkml.kernel.org/r/20170404220148.28338-4-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6fe4c7f..ff73899 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -552,8 +552,8 @@ mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz)
  * implemented.
  */
 
-static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg,
-					    enum memcg_event_item event)
+static unsigned long memcg_sum_events(struct mem_cgroup *memcg,
+				      enum memcg_event_item event)
 {
 	unsigned long val = 0;
 	int cpu;
@@ -1180,7 +1180,7 @@ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
 			if (memcg1_stats[i] == MEMCG_SWAP && !do_swap_account)
 				continue;
 			pr_cont(" %s:%luKB", memcg1_stat_names[i],
-				K(mem_cgroup_read_stat(iter, memcg1_stats[i])));
+				K(memcg_page_state(iter, memcg1_stats[i])));
 		}
 
 		for (i = 0; i < NR_LRU_LISTS; i++)
@@ -2713,7 +2713,7 @@ static void tree_stat(struct mem_cgroup *memcg, unsigned long *stat)
 
 	for_each_mem_cgroup_tree(iter, memcg) {
 		for (i = 0; i < MEMCG_NR_STAT; i++)
-			stat[i] += mem_cgroup_read_stat(iter, i);
+			stat[i] += memcg_page_state(iter, i);
 	}
 }
 
@@ -2726,7 +2726,7 @@ static void tree_events(struct mem_cgroup *memcg, unsigned long *events)
 
 	for_each_mem_cgroup_tree(iter, memcg) {
 		for (i = 0; i < MEMCG_NR_EVENTS; i++)
-			events[i] += mem_cgroup_read_events(iter, i);
+			events[i] += memcg_sum_events(iter, i);
 	}
 }
 
@@ -2738,10 +2738,10 @@ static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap)
 		struct mem_cgroup *iter;
 
 		for_each_mem_cgroup_tree(iter, memcg) {
-			val += mem_cgroup_read_stat(iter, MEMCG_CACHE);
-			val += mem_cgroup_read_stat(iter, MEMCG_RSS);
+			val += memcg_page_state(iter, MEMCG_CACHE);
+			val += memcg_page_state(iter, MEMCG_RSS);
 			if (swap)
-				val += mem_cgroup_read_stat(iter, MEMCG_SWAP);
+				val += memcg_page_state(iter, MEMCG_SWAP);
 		}
 	} else {
 		if (!swap)
@@ -3145,13 +3145,13 @@ static int memcg_stat_show(struct seq_file *m, void *v)
 		if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account())
 			continue;
 		seq_printf(m, "%s %lu\n", memcg1_stat_names[i],
-			   mem_cgroup_read_stat(memcg, memcg1_stats[i]) *
+			   memcg_page_state(memcg, memcg1_stats[i]) *
 			   PAGE_SIZE);
 	}
 
 	for (i = 0; i < ARRAY_SIZE(memcg1_events); i++)
 		seq_printf(m, "%s %lu\n", memcg1_event_names[i],
-			   mem_cgroup_read_events(memcg, memcg1_events[i]));
+			   memcg_sum_events(memcg, memcg1_events[i]));
 
 	for (i = 0; i < NR_LRU_LISTS; i++)
 		seq_printf(m, "%s %lu\n", mem_cgroup_lru_names[i],
@@ -3175,7 +3175,7 @@ static int memcg_stat_show(struct seq_file *m, void *v)
 		if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account())
 			continue;
 		for_each_mem_cgroup_tree(mi, memcg)
-			val += mem_cgroup_read_stat(mi, memcg1_stats[i]) *
+			val += memcg_page_state(mi, memcg1_stats[i]) *
 			PAGE_SIZE;
 		seq_printf(m, "total_%s %llu\n", memcg1_stat_names[i], val);
 	}
@@ -3184,7 +3184,7 @@ static int memcg_stat_show(struct seq_file *m, void *v)
 		unsigned long long val = 0;
 
 		for_each_mem_cgroup_tree(mi, memcg)
-			val += mem_cgroup_read_events(mi, memcg1_events[i]);
+			val += memcg_sum_events(mi, memcg1_events[i]);
 		seq_printf(m, "total_%s %llu\n", memcg1_event_names[i], val);
 	}
 
@@ -3650,10 +3650,10 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
 	struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css);
 	struct mem_cgroup *parent;
 
-	*pdirty = mem_cgroup_read_stat(memcg, NR_FILE_DIRTY);
+	*pdirty = memcg_page_state(memcg, NR_FILE_DIRTY);
 
 	/* this should eventually include NR_UNSTABLE_NFS */
-	*pwriteback = mem_cgroup_read_stat(memcg, NR_WRITEBACK);
+	*pwriteback = memcg_page_state(memcg, NR_WRITEBACK);
 	*pfilepages = mem_cgroup_nr_lru_pages(memcg, (1 << LRU_INACTIVE_FILE) |
 						     (1 << LRU_ACTIVE_FILE));
 	*pheadroom = PAGE_COUNTER_MAX;
@@ -4515,7 +4515,7 @@ static int mem_cgroup_move_account(struct page *page,
 
 	/*
 	 * move_lock grabbed above and caller set from->moving_account, so
-	 * mem_cgroup_update_page_stat() will serialize updates to PageDirty.
+	 * mod_memcg_page_state will serialize updates to PageDirty.
 	 * So mapping should be stable for dirty pages.
 	 */
 	if (!anon && PageDirty(page)) {
@@ -5161,10 +5161,10 @@ static int memory_events_show(struct seq_file *m, void *v)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m));
 
-	seq_printf(m, "low %lu\n", mem_cgroup_read_events(memcg, MEMCG_LOW));
-	seq_printf(m, "high %lu\n", mem_cgroup_read_events(memcg, MEMCG_HIGH));
-	seq_printf(m, "max %lu\n", mem_cgroup_read_events(memcg, MEMCG_MAX));
-	seq_printf(m, "oom %lu\n", mem_cgroup_read_events(memcg, MEMCG_OOM));
+	seq_printf(m, "low %lu\n", memcg_sum_events(memcg, MEMCG_LOW));
+	seq_printf(m, "high %lu\n", memcg_sum_events(memcg, MEMCG_HIGH));
+	seq_printf(m, "max %lu\n", memcg_sum_events(memcg, MEMCG_MAX));
+	seq_printf(m, "oom %lu\n", memcg_sum_events(memcg, MEMCG_OOM));
 
 	return 0;
 }
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 7777112..2359608 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2427,7 +2427,7 @@ void account_page_dirtied(struct page *page, struct address_space *mapping)
 		inode_attach_wb(inode, page);
 		wb = inode_to_wb(inode);
 
-		mem_cgroup_inc_page_stat(page, NR_FILE_DIRTY);
+		inc_memcg_page_state(page, NR_FILE_DIRTY);
 		__inc_node_page_state(page, NR_FILE_DIRTY);
 		__inc_zone_page_state(page, NR_ZONE_WRITE_PENDING);
 		__inc_node_page_state(page, NR_DIRTIED);
@@ -2449,7 +2449,7 @@ void account_page_cleaned(struct page *page, struct address_space *mapping,
 			  struct bdi_writeback *wb)
 {
 	if (mapping_cap_account_dirty(mapping)) {
-		mem_cgroup_dec_page_stat(page, NR_FILE_DIRTY);
+		dec_memcg_page_state(page, NR_FILE_DIRTY);
 		dec_node_page_state(page, NR_FILE_DIRTY);
 		dec_zone_page_state(page, NR_ZONE_WRITE_PENDING);
 		dec_wb_stat(wb, WB_RECLAIMABLE);
@@ -2706,7 +2706,7 @@ int clear_page_dirty_for_io(struct page *page)
 		 */
 		wb = unlocked_inode_to_wb_begin(inode, &locked);
 		if (TestClearPageDirty(page)) {
-			mem_cgroup_dec_page_stat(page, NR_FILE_DIRTY);
+			dec_memcg_page_state(page, NR_FILE_DIRTY);
 			dec_node_page_state(page, NR_FILE_DIRTY);
 			dec_zone_page_state(page, NR_ZONE_WRITE_PENDING);
 			dec_wb_stat(wb, WB_RECLAIMABLE);
@@ -2753,7 +2753,7 @@ int test_clear_page_writeback(struct page *page)
 		ret = TestClearPageWriteback(page);
 	}
 	if (ret) {
-		mem_cgroup_dec_page_stat(page, NR_WRITEBACK);
+		dec_memcg_page_state(page, NR_WRITEBACK);
 		dec_node_page_state(page, NR_WRITEBACK);
 		dec_zone_page_state(page, NR_ZONE_WRITE_PENDING);
 		inc_node_page_state(page, NR_WRITTEN);
@@ -2808,7 +2808,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write)
 		ret = TestSetPageWriteback(page);
 	}
 	if (!ret) {
-		mem_cgroup_inc_page_stat(page, NR_WRITEBACK);
+		inc_memcg_page_state(page, NR_WRITEBACK);
 		inc_node_page_state(page, NR_WRITEBACK);
 		inc_zone_page_state(page, NR_ZONE_WRITE_PENDING);
 	}
diff --git a/mm/rmap.c b/mm/rmap.c
index a6d018c..3ff241f 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1158,7 +1158,7 @@ void page_add_file_rmap(struct page *page, bool compound)
 			goto out;
 	}
 	__mod_node_page_state(page_pgdat(page), NR_FILE_MAPPED, nr);
-	mem_cgroup_update_page_stat(page, NR_FILE_MAPPED, nr);
+	mod_memcg_page_state(page, NR_FILE_MAPPED, nr);
 out:
 	unlock_page_memcg(page);
 }
@@ -1198,7 +1198,7 @@ static void page_remove_file_rmap(struct page *page, bool compound)
 	 * pte lock(a spinlock) is held, which implies preemption disabled.
 	 */
 	__mod_node_page_state(page_pgdat(page), NR_FILE_MAPPED, -nr);
-	mem_cgroup_update_page_stat(page, NR_FILE_MAPPED, -nr);
+	mod_memcg_page_state(page, NR_FILE_MAPPED, -nr);
 
 	if (unlikely(PageMlocked(page)))
 		clear_page_mlock(page);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 417b665..4e7ed65 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2046,7 +2046,7 @@ static bool inactive_list_is_low(struct lruvec *lruvec, bool file,
 	active = lruvec_lru_size(lruvec, active_lru, sc->reclaim_idx);
 
 	if (memcg)
-		refaults = mem_cgroup_read_stat(memcg, WORKINGSET_ACTIVATE);
+		refaults = memcg_page_state(memcg, WORKINGSET_ACTIVATE);
 	else
 		refaults = node_page_state(pgdat, WORKINGSET_ACTIVATE);
 
@@ -2733,8 +2733,7 @@ static void snapshot_refaults(struct mem_cgroup *root_memcg, pg_data_t *pgdat)
 		struct lruvec *lruvec;
 
 		if (memcg)
-			refaults = mem_cgroup_read_stat(memcg,
-							WORKINGSET_ACTIVATE);
+			refaults = memcg_page_state(memcg, WORKINGSET_ACTIVATE);
 		else
 			refaults = node_page_state(pgdat, WORKINGSET_ACTIVATE);
 
diff --git a/mm/workingset.c b/mm/workingset.c
index 37fc105..b8c9ab6 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -289,11 +289,11 @@ bool workingset_refault(void *shadow)
 	refault_distance = (refault - eviction) & EVICTION_MASK;
 
 	inc_node_state(pgdat, WORKINGSET_REFAULT);
-	mem_cgroup_inc_stat(memcg, WORKINGSET_REFAULT);
+	inc_memcg_state(memcg, WORKINGSET_REFAULT);
 
 	if (refault_distance <= active_file) {
 		inc_node_state(pgdat, WORKINGSET_ACTIVATE);
-		mem_cgroup_inc_stat(memcg, WORKINGSET_ACTIVATE);
+		inc_memcg_state(memcg, WORKINGSET_ACTIVATE);
 		rcu_read_unlock();
 		return true;
 	}
@@ -475,7 +475,7 @@ static enum lru_status shadow_lru_isolate(struct list_head *item,
 	if (WARN_ON_ONCE(node->exceptional))
 		goto out_invalid;
 	inc_node_state(page_pgdat(virt_to_page(node)), WORKINGSET_NODERECLAIM);
-	mem_cgroup_inc_page_stat(virt_to_page(node), WORKINGSET_NODERECLAIM);
+	inc_memcg_page_state(virt_to_page(node), WORKINGSET_NODERECLAIM);
 	__radix_tree_delete_node(&mapping->page_tree, node,
 				 workingset_update_node, mapping);