---

yaml
---
r: 272128
b: refs/heads/master
c: f84f6e2
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 966dbde2c208e07bab7a45a7855e1e693eabe661
+refs/heads/master: f84f6e2b0868f198f97a32ba503d6f9f319a249a

trunk/mm/vmscan.c

@@ -750,7 +750,8 @@ static noinline_for_stack void free_page_list(struct list_head *free_pages)
  */
 static unsigned long shrink_page_list(struct list_head *page_list,
 				      struct zone *zone,
-				      struct scan_control *sc)
+				      struct scan_control *sc,
+				      int priority)
 {
 	LIST_HEAD(ret_pages);
 	LIST_HEAD(free_pages);
@@ -856,9 +857,11 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 
 			/*
 			 * Only kswapd can writeback filesystem pages to
-			 * avoid risk of stack overflow
+			 * avoid risk of stack overflow but do not writeback
+			 * unless under significant pressure.
 			 */
-			if (page_is_file_cache(page) && !current_is_kswapd()) {
+			if (page_is_file_cache(page) &&
+					(!current_is_kswapd() || priority >= DEF_PRIORITY - 2)) {
 				inc_zone_page_state(page, NR_VMSCAN_WRITE_SKIP);
 				goto keep_locked;
 			}
@@ -1509,12 +1512,12 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone,
 
 	spin_unlock_irq(&zone->lru_lock);
 
-	nr_reclaimed = shrink_page_list(&page_list, zone, sc);
+	nr_reclaimed = shrink_page_list(&page_list, zone, sc, priority);
 
 	/* Check if we should syncronously wait for writeback */
 	if (should_reclaim_stall(nr_taken, nr_reclaimed, priority, sc)) {
 		set_reclaim_mode(priority, sc, true);
-		nr_reclaimed += shrink_page_list(&page_list, zone, sc);
+		nr_reclaimed += shrink_page_list(&page_list, zone, sc, priority);
 	}
 
 	local_irq_disable();