mm: move definition for LRU isolation modes to a header

[~andy/linux] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 596180fedd3ac8ba3ff328ae0f272b911662dc94..cefe6fe8d991b32b1b0e66c86953d92e00c39aea 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1990,10 +1990,13 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
        if (unlikely(!zonelist->_zonerefs->zone))
                return NULL;
 
+       get_mems_allowed();
        /* The preferred zone is used for statistics later */
        first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone);
-       if (!preferred_zone)
+       if (!preferred_zone) {
+               put_mems_allowed();
                return NULL;
+       }
 
        /* First allocation attempt */
        page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
@@ -2003,6 +2006,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
                page = __alloc_pages_slowpath(gfp_mask, order,
                                zonelist, high_zoneidx, nodemask,
                                preferred_zone, migratetype);
+       put_mems_allowed();
 
        trace_mm_page_alloc(page, order, gfp_mask, migratetype);
        return page;
@@ -2602,7 +2606,7 @@ static int default_zonelist_order(void)
          * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
         * If they are really small and used heavily, the system can fall
         * into OOM very easily.
-        * This function detect ZONE_DMA/DMA32 size and confgigures zone order.
+        * This function detect ZONE_DMA/DMA32 size and configures zone order.
         */
        /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
        low_kmem_size = 0;
@@ -2614,6 +2618,15 @@ static int default_zonelist_order(void)
                                if (zone_type < ZONE_NORMAL)
                                        low_kmem_size += z->present_pages;
                                total_size += z->present_pages;
+                       } else if (zone_type == ZONE_NORMAL) {
+                               /*
+                                * If any node has only lowmem, then node order
+                                * is preferred to allow kernel allocations
+                                * locally; otherwise, they can easily infringe
+                                * on other nodes when there is an abundance of
+                                * lowmem available to allocate from.
+                                */
+                               return ZONELIST_ORDER_NODE;
                        }
                }
        }