[PATCH] vm: shrink slab evenly in try_to_free_pages()

From: Nick Piggin <piggin@cyberone.com.au>

In try_to_free_pages(), put even pressure on the slab even if we have
reclaimed enough pages from the LRU.

mm/vmscan.c

@@ -875,6 +875,13 @@ int try_to_free_pages(struct zone **zones,
 		get_page_state(&ps);
 		nr_reclaimed += shrink_caches(zones, priority, &total_scanned,
 						gfp_mask, nr_pages, &ps);
+		if (zones[0] - zones[0]->zone_pgdat->node_zones < ZONE_HIGHMEM) {
+			shrink_slab(total_scanned, gfp_mask);
+			if (reclaim_state) {
+				nr_reclaimed += reclaim_state->reclaimed_slab;
+				reclaim_state->reclaimed_slab = 0;
+			}
+		}
 		if (nr_reclaimed >= nr_pages) {
 			ret = 1;
 			goto out;
@@ -890,13 +897,6 @@ int try_to_free_pages(struct zone **zones,
 
 		/* Take a nap, wait for some writeback to complete */
 		blk_congestion_wait(WRITE, HZ/10);
-		if (zones[0] - zones[0]->zone_pgdat->node_zones < ZONE_HIGHMEM) {
-			shrink_slab(total_scanned, gfp_mask);
-			if (reclaim_state) {
-				nr_reclaimed += reclaim_state->reclaimed_slab;
-				reclaim_state->reclaimed_slab = 0;
-			}
-		}
 	}
 	if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY))
 		out_of_memory();