diff --git a/mm/vmscan.c b/mm/vmscan.c
index 1b4e4a597ca..a3d669f8e25 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1627,6 +1627,13 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc,
 		}
 	}
 
+	/*
+	 * With swappiness at 100, anonymous and file have the same priority.
+	 * This scanning priority is essentially the inverse of IO cost.
+	 */
+	anon_prio = sc->swappiness;
+	file_prio = 200 - sc->swappiness;
+
 	/*
 	 * OK, so we have swap space and a fair amount of page cache
 	 * pages.  We use the recently rotated / recently scanned
@@ -1638,27 +1645,17 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc,
 	 *
 	 * anon in [0], file in [1]
 	 */
+	spin_lock_irq(&zone->lru_lock);
 	if (unlikely(reclaim_stat->recent_scanned[0] > anon / 4)) {
-		spin_lock_irq(&zone->lru_lock);
 		reclaim_stat->recent_scanned[0] /= 2;
 		reclaim_stat->recent_rotated[0] /= 2;
-		spin_unlock_irq(&zone->lru_lock);
 	}
 
 	if (unlikely(reclaim_stat->recent_scanned[1] > file / 4)) {
-		spin_lock_irq(&zone->lru_lock);
 		reclaim_stat->recent_scanned[1] /= 2;
 		reclaim_stat->recent_rotated[1] /= 2;
-		spin_unlock_irq(&zone->lru_lock);
 	}
 
-	/*
-	 * With swappiness at 100, anonymous and file have the same priority.
-	 * This scanning priority is essentially the inverse of IO cost.
-	 */
-	anon_prio = sc->swappiness;
-	file_prio = 200 - sc->swappiness;
-
 	/*
 	 * The amount of pressure on anon vs file pages is inversely
 	 * proportional to the fraction of recently scanned pages on
@@ -1669,6 +1666,7 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc,
 
 	fp = (file_prio + 1) * (reclaim_stat->recent_scanned[1] + 1);
 	fp /= reclaim_stat->recent_rotated[1] + 1;
+	spin_unlock_irq(&zone->lru_lock);
 
 	fraction[0] = ap;
 	fraction[1] = fp;