buddy: clarify comments describing buddy merge

[linux-2.6-omap-h63xx.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index f024b9b3a2a6d1ea9d455a1e0e019391e57a606d..24aa3d1b9d9698770831be0c512164a1cd64fd62 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -432,8 +432,9 @@ static inline void __free_one_page(struct page *page,
 
                buddy = __page_find_buddy(page, page_idx, order);
                if (!page_is_buddy(page, buddy, order))
-                       break;          /* Move the buddy up one level. */
+                       break;
 
+               /* Our buddy is free, merge with it and move up one order. */
                list_del(&buddy->lru);
                zone->free_area[order].nr_free--;
                rmv_page_order(buddy);
@@ -918,7 +919,7 @@ void drain_local_pages(void *arg)
  */
 void drain_all_pages(void)
 {
-       on_each_cpu(drain_local_pages, NULL, 0, 1);
+       on_each_cpu(drain_local_pages, NULL, 1);
 }
 
 #ifdef CONFIG_HIBERNATION
@@ -1429,7 +1430,7 @@ try_next_zone:
 /*
  * This is the 'heart' of the zoned buddy allocator.
  */
-static struct page *
+struct page *
 __alloc_pages_internal(gfp_t gfp_mask, unsigned int order,
                        struct zonelist *zonelist, nodemask_t *nodemask)
 {
@@ -1632,22 +1633,7 @@ nopage:
 got_pg:
        return page;
 }
-
-struct page *
-__alloc_pages(gfp_t gfp_mask, unsigned int order,
-               struct zonelist *zonelist)
-{
-       return __alloc_pages_internal(gfp_mask, order, zonelist, NULL);
-}
-
-struct page *
-__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
-               struct zonelist *zonelist, nodemask_t *nodemask)
-{
-       return __alloc_pages_internal(gfp_mask, order, zonelist, nodemask);
-}
-
-EXPORT_SYMBOL(__alloc_pages);
+EXPORT_SYMBOL(__alloc_pages_internal);
 
 /*
  * Common helper functions.
@@ -2352,6 +2338,7 @@ void build_all_zonelists(void)
 
        if (system_state == SYSTEM_BOOTING) {
                __build_all_zonelists(NULL);
+               mminit_verify_zonelist();
                cpuset_init_current_mems_allowed();
        } else {
                /* we have to stop all cpus to guarantee there is no user
@@ -2534,6 +2521,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
                }
                page = pfn_to_page(pfn);
                set_page_links(page, zone, nid, pfn);
+               mminit_verify_page_links(page, zone, nid, pfn);
                init_page_count(page);
                reset_page_mapcount(page);
                SetPageReserved(page);
@@ -2836,6 +2824,12 @@ __meminit int init_currently_empty_zone(struct zone *zone,
 
        zone->zone_start_pfn = zone_start_pfn;
 
+       mminit_dprintk(MMINIT_TRACE, "memmap_init",
+                       "Initialising map node %d zone %lu pfns %lu -> %lu\n",
+                       pgdat->node_id,
+                       (unsigned long)zone_idx(zone),
+                       zone_start_pfn, (zone_start_pfn + size));
+
        zone_init_free_lists(zone);
 
        return 0;
@@ -2975,7 +2969,8 @@ void __init sparse_memory_present_with_active_regions(int nid)
 void __init push_node_boundaries(unsigned int nid,
                unsigned long start_pfn, unsigned long end_pfn)
 {
-       printk(KERN_DEBUG "Entering push_node_boundaries(%u, %lu, %lu)\n",
+       mminit_dprintk(MMINIT_TRACE, "zoneboundary",
+                       "Entering push_node_boundaries(%u, %lu, %lu)\n",
                        nid, start_pfn, end_pfn);
 
        /* Initialise the boundary for this node if necessary */
@@ -2993,7 +2988,8 @@ void __init push_node_boundaries(unsigned int nid,
 static void __meminit account_node_boundary(unsigned int nid,
                unsigned long *start_pfn, unsigned long *end_pfn)
 {
-       printk(KERN_DEBUG "Entering account_node_boundary(%u, %lu, %lu)\n",
+       mminit_dprintk(MMINIT_TRACE, "zoneboundary",
+                       "Entering account_node_boundary(%u, %lu, %lu)\n",
                        nid, *start_pfn, *end_pfn);
 
        /* Return if boundary information has not been provided */
@@ -3368,8 +3364,8 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
                        PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT;
                if (realsize >= memmap_pages) {
                        realsize -= memmap_pages;
-                       printk(KERN_DEBUG
-                               "  %s zone: %lu pages used for memmap\n",
+                       mminit_dprintk(MMINIT_TRACE, "memmap_init",
+                               "%s zone: %lu pages used for memmap\n",
                                zone_names[j], memmap_pages);
                } else
                        printk(KERN_WARNING
@@ -3379,7 +3375,8 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
                /* Account for reserved pages */
                if (j == 0 && realsize > dma_reserve) {
                        realsize -= dma_reserve;
-                       printk(KERN_DEBUG "  %s zone: %lu pages reserved\n",
+                       mminit_dprintk(MMINIT_TRACE, "memmap_init",
+                                       "%s zone: %lu pages reserved\n",
                                        zone_names[0], dma_reserve);
                }
 
@@ -3520,10 +3517,13 @@ void __init add_active_range(unsigned int nid, unsigned long start_pfn,
 {
        int i;
 
-       printk(KERN_DEBUG "Entering add_active_range(%d, %#lx, %#lx) "
-                         "%d entries of %d used\n",
-                         nid, start_pfn, end_pfn,
-                         nr_nodemap_entries, MAX_ACTIVE_REGIONS);
+       mminit_dprintk(MMINIT_TRACE, "memory_register",
+                       "Entering add_active_range(%d, %#lx, %#lx) "
+                       "%d entries of %d used\n",
+                       nid, start_pfn, end_pfn,
+                       nr_nodemap_entries, MAX_ACTIVE_REGIONS);
+
+       mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
 
        /* Merge with existing active regions if possible */
        for (i = 0; i < nr_nodemap_entries; i++) {
@@ -3957,6 +3957,7 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
                                                early_node_map[i].end_pfn);
 
        /* Initialise every node */
+       mminit_verify_pageflags_layout();
        setup_nr_node_ids();
        for_each_online_node(nid) {
                pg_data_t *pgdat = NODE_DATA(nid);
@@ -4025,9 +4026,7 @@ void __init set_dma_reserve(unsigned long new_dma_reserve)
 }
 
 #ifndef CONFIG_NEED_MULTIPLE_NODES
-static bootmem_data_t contig_bootmem_data;
-struct pglist_data contig_page_data = { .bdata = &contig_bootmem_data };
-
+struct pglist_data contig_page_data = { .bdata = &bootmem_node_data[0] };
 EXPORT_SYMBOL(contig_page_data);
 #endif