diff --git a/mm/vmscan.c b/mm/vmscan.c
index f83a7ed5c6c..7ea1440b53d 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1389,9 +1389,9 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc,
 	file_prio = 200 - sc->swappiness;
 
 	/*
-	 *                  anon       recent_rotated[0]
-	 * %anon = 100 * ----------- / ----------------- * IO cost
-	 *               anon + file      rotate_sum
+	 * The amount of pressure on anon vs file pages is inversely
+	 * proportional to the fraction of recently scanned pages on
+	 * each list that were recently referenced and in active use.
 	 */
 	ap = (anon_prio + 1) * (zone->recent_scanned[0] + 1);
 	ap /= zone->recent_rotated[0] + 1;