sched: RT-balance, avoid overloading

[pandora-kernel.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 4ffed1c..b2838c2 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -847,8 +847,19 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
                struct page *page = __rmqueue(zone, order, migratetype);
                if (unlikely(page == NULL))
                        break;
+
+               /*
+                * Split buddy pages returned by expand() are received here
+                * in physical page order. The page is added to the callers and
+                * list and the list head then moves forward. From the callers
+                * perspective, the linked list is ordered by page number in
+                * some conditions. This is useful for IO devices that can
+                * merge IO requests if the physical pages are ordered
+                * properly.
+                */
                list_add(&page->lru, list);
                set_page_private(page, migratetype);
+               list = &page->lru;
        }
        spin_unlock(&zone->lock);
        return i;
@@ -2555,7 +2566,7 @@ static void __meminit zone_init_free_lists(struct pglist_data *pgdat,
        memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
 #endif
 
-static int __devinit zone_batchsize(struct zone *zone)
+static int zone_batchsize(struct zone *zone)
 {
        int batch;
 
@@ -3265,6 +3276,16 @@ static void inline setup_usemap(struct pglist_data *pgdat,
 #endif /* CONFIG_SPARSEMEM */
 
 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
+
+/* Return a sensible default order for the pageblock size. */
+static inline int pageblock_default_order(void)
+{
+       if (HPAGE_SHIFT > PAGE_SHIFT)
+               return HUGETLB_PAGE_ORDER;
+
+       return MAX_ORDER-1;
+}
+
 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
 static inline void __init set_pageblock_order(unsigned int order)
 {
@@ -3280,7 +3301,16 @@ static inline void __init set_pageblock_order(unsigned int order)
 }
 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
 
-/* Defined this way to avoid accidently referencing HUGETLB_PAGE_ORDER */
+/*
+ * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
+ * and pageblock_default_order() are unused as pageblock_order is set
+ * at compile-time. See include/linux/pageblock-flags.h for the values of
+ * pageblock_order based on the kernel config
+ */
+static inline int pageblock_default_order(unsigned int order)
+{
+       return MAX_ORDER-1;
+}
 #define set_pageblock_order(x) do {} while (0)
 
 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
@@ -3365,7 +3395,7 @@ static void __meminit free_area_init_core(struct pglist_data *pgdat,
                if (!size)
                        continue;
 
-               set_pageblock_order(HUGETLB_PAGE_ORDER);
+               set_pageblock_order(pageblock_default_order());
                setup_usemap(pgdat, zone, size);
                ret = init_currently_empty_zone(zone, zone_start_pfn,
                                                size, MEMMAP_EARLY);
@@ -3408,7 +3438,7 @@ static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
                mem_map = NODE_DATA(0)->node_mem_map;
 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
                if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
-                       mem_map -= pgdat->node_start_pfn;
+                       mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET);
 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
        }
 #endif