memcg: rearrange code

This is a preparatory patch for easing the review of the follow up patch
which will reduce the memory overhead of memory cgroups.

Link: https://lkml.kernel.org/r/20220907043537.3457014-3-shakeelb@google.comSigned-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/memcontrol.c

@@ -669,6 +669,29 @@ static void flush_memcg_stats_dwork(struct work_struct *w)
 	queue_delayed_work(system_unbound_wq, &stats_flush_dwork, FLUSH_TIME);
 }
 
+/* Subset of vm_event_item to report for memcg event stats */
+static const unsigned int memcg_vm_event_stat[] = {
+	PGSCAN_KSWAPD,
+	PGSCAN_DIRECT,
+	PGSTEAL_KSWAPD,
+	PGSTEAL_DIRECT,
+	PGFAULT,
+	PGMAJFAULT,
+	PGREFILL,
+	PGACTIVATE,
+	PGDEACTIVATE,
+	PGLAZYFREE,
+	PGLAZYFREED,
+#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
+	ZSWPIN,
+	ZSWPOUT,
+#endif
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	THP_FAULT_ALLOC,
+	THP_COLLAPSE_ALLOC,
+#endif
+};
+
 struct memcg_vmstats_percpu {
 	/* Local (CPU and cgroup) page state & events */
 	long			state[MEMCG_NR_STAT];
@@ -1501,29 +1524,6 @@ static inline unsigned long memcg_page_state_output(struct mem_cgroup *memcg,
 	return memcg_page_state(memcg, item) * memcg_page_state_unit(item);
 }
 
-/* Subset of vm_event_item to report for memcg event stats */
-static const unsigned int memcg_vm_event_stat[] = {
-	PGSCAN_KSWAPD,
-	PGSCAN_DIRECT,
-	PGSTEAL_KSWAPD,
-	PGSTEAL_DIRECT,
-	PGFAULT,
-	PGMAJFAULT,
-	PGREFILL,
-	PGACTIVATE,
-	PGDEACTIVATE,
-	PGLAZYFREE,
-	PGLAZYFREED,
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
-	ZSWPIN,
-	ZSWPOUT,
-#endif
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	THP_FAULT_ALLOC,
-	THP_COLLAPSE_ALLOC,
-#endif
-};
-
 static void memory_stat_format(struct mem_cgroup *memcg, char *buf, int bufsize)
 {
 	struct seq_buf s;