X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=mm%2Fpage_alloc.c;h=b2838c24e582c11b8e0680ca5d5b5f97389145ba;hb=d69a3ad6a0e47b2aa9b2b2ddfd385752132a4d34;hp=43f757fcf30f6b1dc61cffd2c824e791db28c418;hpb=e6d5a11dad44b8ae18ca8fc4ecb72ccccfa0a2d2;p=linux-2.6-omap-h63xx.git

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 43f757fcf30..b2838c24e58 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -123,7 +123,7 @@ static unsigned long __meminitdata dma_reserve;
 
 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
   /*
-   * MAX_ACTIVE_REGIONS determines the maxmimum number of distinct
+   * MAX_ACTIVE_REGIONS determines the maximum number of distinct
    * ranges of memory (RAM) that may be registered with add_active_range().
    * Ranges passed to add_active_range() will be merged if possible
    * so the number of times add_active_range() can be called is
@@ -305,7 +305,6 @@ static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags)
 {
 	int i;
 
-	VM_BUG_ON((gfp_flags & (__GFP_WAIT | __GFP_HIGHMEM)) == __GFP_HIGHMEM);
 	/*
 	 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
 	 * and __GFP_HIGHMEM from hard or soft interrupt context.
@@ -749,23 +748,6 @@ int move_freepages_block(struct zone *zone, struct page *page, int migratetype)
 	return move_freepages(zone, start_page, end_page, migratetype);
 }
 
-/* Return the page with the lowest PFN in the list */
-static struct page *min_page(struct list_head *list)
-{
-	unsigned long min_pfn = -1UL;
-	struct page *min_page = NULL, *page;;
-
-	list_for_each_entry(page, list, lru) {
-		unsigned long pfn = page_to_pfn(page);
-		if (pfn < min_pfn) {
-			min_pfn = pfn;
-			min_page = page;
-		}
-	}
-
-	return min_page;
-}
-
 /* Remove an element from the buddy allocator from the fallback list */
 static struct page *__rmqueue_fallback(struct zone *zone, int order,
 						int start_migratetype)
@@ -789,11 +771,8 @@ static struct page *__rmqueue_fallback(struct zone *zone, int order,
 			if (list_empty(&area->free_list[migratetype]))
 				continue;
 
-			/* Bias kernel allocations towards low pfns */
 			page = list_entry(area->free_list[migratetype].next,
 					struct page, lru);
-			if (unlikely(start_migratetype != MIGRATE_MOVABLE))
-				page = min_page(&area->free_list[migratetype]);
 			area->nr_free--;
 
 			/*
@@ -868,8 +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;
@@ -1260,7 +1250,7 @@ int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
  * skip over zones that are not allowed by the cpuset, or that have
  * been recently (in last second) found to be nearly full.  See further
  * comments in mmzone.h.  Reduces cache footprint of zonelist scans
- * that have to skip over alot of full or unallowed zones.
+ * that have to skip over a lot of full or unallowed zones.
  *
  * If the zonelist cache is present in the passed in zonelist, then
  * returns a pointer to the allowed node mask (either the current
@@ -2358,7 +2348,7 @@ void build_all_zonelists(void)
 		__build_all_zonelists(NULL);
 		cpuset_init_current_mems_allowed();
 	} else {
-		/* we have to stop all cpus to guaranntee there is no user
+		/* we have to stop all cpus to guarantee there is no user
 		   of zonelist */
 		stop_machine_run(__build_all_zonelists, NULL, NR_CPUS);
 		/* cpuset refresh routine should be here */
@@ -2576,7 +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;
 
@@ -2864,7 +2854,7 @@ static int __meminit first_active_region_index_in_nid(int nid)
 
 /*
  * Basic iterator support. Return the next active range of PFNs for a node
- * Note: nid == MAX_NUMNODES returns next region regardles of node
+ * Note: nid == MAX_NUMNODES returns next region regardless of node
  */
 static int __meminit next_active_region_index_in_nid(int index, int nid)
 {
@@ -3286,6 +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)
 {
@@ -3301,7 +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 */
@@ -3386,7 +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);
@@ -3429,7 +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