1 files changed, 4 insertions, 2 deletions
diff --git a/mm/vmstat.c b/mm/vmstat.c
index e1d8ed172c4..f42745e6578 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -52,7 +52,6 @@ void all_vm_events(unsigned long *ret)
 }
 EXPORT_SYMBOL_GPL(all_vm_events);
 
-#ifdef CONFIG_HOTPLUG
 /*
  * Fold the foreign cpu events into our own.
  *
@@ -69,7 +68,6 @@ void vm_events_fold_cpu(int cpu)
 		fold_state->event[i] = 0;
 	}
 }
-#endif /* CONFIG_HOTPLUG */
 
 #endif /* CONFIG_VM_EVENT_COUNTERS */
 
@@ -495,6 +493,10 @@ void refresh_cpu_vm_stats(int cpu)
 			atomic_long_add(global_diff[i], &vm_stat[i]);
 }
 
+/*
+ * this is only called if !populated_zone(zone), which implies no other users of
+ * pset->vm_stat_diff[] exsist.
+ */
 void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset)
 {
 	int i;