1 files changed, 13 insertions, 3 deletions

diff --git a/mm/internal.h b/mm/internal.h
index 48e32f790571..1cfbf2e2bc9e 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -101,7 +101,10 @@ static inline int is_mlocked_vma(struct vm_area_struct *vma, struct page *page)
         if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
                 return 0;
 
-        SetPageMlocked(page);
+        if (!TestSetPageMlocked(page)) {
+                inc_zone_page_state(page, NR_MLOCK);
+                count_vm_event(UNEVICTABLE_PGMLOCKED);
+        }
         return 1;
 }
 
@@ -128,12 +131,19 @@ static inline void clear_page_mlock(struct page *page)
 
 /*
  * mlock_migrate_page - called only from migrate_page_copy() to
- * migrate the Mlocked page flag
+ * migrate the Mlocked page flag; update statistics.
  */
 static inline void mlock_migrate_page(struct page *newpage, struct page *page)
 {
-        if (TestClearPageMlocked(page))
+        if (TestClearPageMlocked(page)) {
+                unsigned long flags;
+
+                local_irq_save(flags);
+                __dec_zone_page_state(page, NR_MLOCK);
                 SetPageMlocked(newpage);
+                __inc_zone_page_state(newpage, NR_MLOCK);
+                local_irq_restore(flags);
+        }
 }