quicklists: Only consider memory that can be used with GFP_KERNEL

Quicklists calculates the size of the quicklists based on the number of
free pages.  This must be the number of free pages that can be allocated
with GFP_KERNEL.  node_page_state() includes the pages in ZONE_HIGHMEM and
ZONE_MOVABLE which may lead the quicklists to become too large causing OOM.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Tested-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/quicklist.c

@@ -26,9 +26,17 @@ DEFINE_PER_CPU(struct quicklist, quicklist)[CONFIG_NR_QUICK];
 static unsigned long max_pages(unsigned long min_pages)
 {
 	unsigned long node_free_pages, max;
+	struct zone *zones = NODE_DATA(numa_node_id())->node_zones;
+
+	node_free_pages =
+#ifdef CONFIG_ZONE_DMA
+		zone_page_state(&zones[ZONE_DMA], NR_FREE_PAGES) +
+#endif
+#ifdef CONFIG_ZONE_DMA32
+		zone_page_state(&zones[ZONE_DMA32], NR_FREE_PAGES) +
+#endif
+		zone_page_state(&zones[ZONE_NORMAL], NR_FREE_PAGES);
 
-	node_free_pages = node_page_state(numa_node_id(),
-			NR_FREE_PAGES);
 	max = node_free_pages / FRACTION_OF_NODE_MEM;
 	return max(max, min_pages);
 }