X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=mm%2Fvmscan.c;h=6771ea70bfe7e399d96237a58d3860357aad4c46;hb=5e58e5283a0a0a99ee970e7e5c80c6541693376e;hp=17497d0cd8b9e4c95bf5ce39abf1f59d2eb15f2f;hpb=c09d7a3d2e365e11c09b9c6414c17fe55bd32a8e;p=~andy%2Flinux

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 17497d0cd8b..f73b8657c2d 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -358,7 +358,7 @@ static int may_write_to_queue(struct backing_dev_info *bdi,
 static void handle_write_error(struct address_space *mapping,
 				struct page *page, int error)
 {
-	lock_page_nosync(page);
+	lock_page(page);
 	if (page_mapping(page) == mapping)
 		mapping_set_error(mapping, error);
 	unlock_page(page);
@@ -514,7 +514,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page)
 
 		freepage = mapping->a_ops->freepage;
 
-		__remove_from_page_cache(page);
+		__delete_from_page_cache(page);
 		spin_unlock_irq(&mapping->tree_lock);
 		mem_cgroup_uncharge_cache_page(page);
 
@@ -1841,16 +1841,28 @@ static inline bool should_continue_reclaim(struct zone *zone,
 	if (!(sc->reclaim_mode & RECLAIM_MODE_COMPACTION))
 		return false;
 
-	/*
-	 * If we failed to reclaim and have scanned the full list, stop.
-	 * NOTE: Checking just nr_reclaimed would exit reclaim/compaction far
-	 *       faster but obviously would be less likely to succeed
-	 *       allocation. If this is desirable, use GFP_REPEAT to decide
-	 *       if both reclaimed and scanned should be checked or just
-	 *       reclaimed
-	 */
-	if (!nr_reclaimed && !nr_scanned)
-		return false;
+	/* Consider stopping depending on scan and reclaim activity */
+	if (sc->gfp_mask & __GFP_REPEAT) {
+		/*
+		 * For __GFP_REPEAT allocations, stop reclaiming if the
+		 * full LRU list has been scanned and we are still failing
+		 * to reclaim pages. This full LRU scan is potentially
+		 * expensive but a __GFP_REPEAT caller really wants to succeed
+		 */
+		if (!nr_reclaimed && !nr_scanned)
+			return false;
+	} else {
+		/*
+		 * For non-__GFP_REPEAT allocations which can presumably
+		 * fail without consequence, stop if we failed to reclaim
+		 * any pages from the last SWAP_CLUSTER_MAX number of
+		 * pages that were scanned. This will return to the
+		 * caller faster at the risk reclaim/compaction and
+		 * the resulting allocation attempt fails
+		 */
+		if (!nr_reclaimed)
+			return false;
+	}
 
 	/*
 	 * If we have not reclaimed enough pages for compaction and the
@@ -2385,9 +2397,9 @@ loop_again:
 		 * cause too much scanning of the lower zones.
 		 */
 		for (i = 0; i <= end_zone; i++) {
-			int compaction;
 			struct zone *zone = pgdat->node_zones + i;
 			int nr_slab;
+			unsigned long balance_gap;
 
 			if (!populated_zone(zone))
 				continue;
@@ -2404,11 +2416,20 @@ loop_again:
 			mem_cgroup_soft_limit_reclaim(zone, order, sc.gfp_mask);
 
 			/*
-			 * We put equal pressure on every zone, unless one
-			 * zone has way too many pages free already.
+			 * We put equal pressure on every zone, unless
+			 * one zone has way too many pages free
+			 * already. The "too many pages" is defined
+			 * as the high wmark plus a "gap" where the
+			 * gap is either the low watermark or 1%
+			 * of the zone, whichever is smaller.
 			 */
+			balance_gap = min(low_wmark_pages(zone),
+				(zone->present_pages +
+					KSWAPD_ZONE_BALANCE_GAP_RATIO-1) /
+				KSWAPD_ZONE_BALANCE_GAP_RATIO);
 			if (!zone_watermark_ok_safe(zone, order,
-					8*high_wmark_pages(zone), end_zone, 0))
+					high_wmark_pages(zone) + balance_gap,
+					end_zone, 0))
 				shrink_zone(priority, zone, &sc);
 			reclaim_state->reclaimed_slab = 0;
 			nr_slab = shrink_slab(sc.nr_scanned, GFP_KERNEL,
@@ -2416,24 +2437,9 @@ loop_again:
 			sc.nr_reclaimed += reclaim_state->reclaimed_slab;
 			total_scanned += sc.nr_scanned;
 
-			compaction = 0;
-			if (order &&
-			    zone_watermark_ok(zone, 0,
-					       high_wmark_pages(zone),
-					      end_zone, 0) &&
-			    !zone_watermark_ok(zone, order,
-					       high_wmark_pages(zone),
-					       end_zone, 0)) {
-				compact_zone_order(zone,
-						   order,
-						   sc.gfp_mask, false,
-						   COMPACT_MODE_KSWAPD);
-				compaction = 1;
-			}
-
 			if (zone->all_unreclaimable)
 				continue;
-			if (!compaction && nr_slab == 0 &&
+			if (nr_slab == 0 &&
 			    !zone_reclaimable(zone))
 				zone->all_unreclaimable = 1;
 			/*