1 files changed, 49 insertions, 6 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0f770cc13450..e3f00f622f28 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1062,6 +1062,25 @@ void __defer_init __free_pages_bootmem(struct page *page, unsigned long pfn,
 }
 
 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
+static void __defermem_init deferred_free_range(struct page *page,
+                                        unsigned long pfn, int nr_pages)
+{
+        int i;
+
+        if (!page)
+                return;
+
+        /* Free a large naturally-aligned chunk if possible */
+        if (nr_pages == MAX_ORDER_NR_PAGES &&
+            (pfn & (MAX_ORDER_NR_PAGES-1)) == 0) {
+                __free_pages_boot_core(page, pfn, MAX_ORDER-1);
+                return;
+        }
+
+        for (i = 0; i < nr_pages; i++, page++, pfn++)
+                __free_pages_boot_core(page, pfn, 0);
+}
+
 /* Initialise remaining memory on a node */
 void __defermem_init deferred_init_memmap(int nid)
 {
@@ -1092,6 +1111,9 @@ void __defermem_init deferred_init_memmap(int nid)
         for_each_mem_pfn_range(i, nid, &walk_start, &walk_end, NULL) {
                 unsigned long pfn, end_pfn;
                 struct page *page = NULL;
+                struct page *free_base_page = NULL;
+                unsigned long free_base_pfn = 0;
+                int nr_to_free = 0;
 
                 end_pfn = min(walk_end, zone_end_pfn(zone));
                 pfn = first_init_pfn;
@@ -1102,7 +1124,7 @@ void __defermem_init deferred_init_memmap(int nid)
 
                 for (; pfn < end_pfn; pfn++) {
                         if (!pfn_valid_within(pfn))
-                                continue;
+                                goto free_range;
 
                         /*
                          * Ensure pfn_valid is checked every
@@ -1111,32 +1133,53 @@ void __defermem_init deferred_init_memmap(int nid)
                         if ((pfn & (MAX_ORDER_NR_PAGES - 1)) == 0) {
                                 if (!pfn_valid(pfn)) {
                                         page = NULL;
-                                        continue;
+                                        goto free_range;
                                 }
                         }
 
                         if (!meminit_pfn_in_nid(pfn, nid, &nid_init_state)) {
                                 page = NULL;
-                                continue;
+                                goto free_range;
                         }
 
                         /* Minimise pfn page lookups and scheduler checks */
                         if (page && (pfn & (MAX_ORDER_NR_PAGES - 1)) != 0) {
                                 page++;
                         } else {
+                                nr_pages += nr_to_free;
+                                deferred_free_range(free_base_page,
+                                                free_base_pfn, nr_to_free);
+                                free_base_page = NULL;
+                                free_base_pfn = nr_to_free = 0;
+
                                 page = pfn_to_page(pfn);
                                 cond_resched();
                         }
 
                         if (page->flags) {
                                 VM_BUG_ON(page_zone(page) != zone);
-                                continue;
+                                goto free_range;
                         }
 
                         __init_single_page(page, pfn, zid, nid);
-                        __free_pages_boot_core(page, pfn, 0);
-                        nr_pages++;
+                        if (!free_base_page) {
+                                free_base_page = page;
+                                free_base_pfn = pfn;
+                                nr_to_free = 0;
+                        }
+                        nr_to_free++;
+
+                        /* Where possible, batch up pages for a single free */
+                        continue;
+free_range:
+                        /* Free the current block of pages to allocator */
+                        nr_pages += nr_to_free;
+                        deferred_free_range(free_base_page, free_base_pfn,
+                                                                nr_to_free);
+                        free_base_page = NULL;
+                        free_base_pfn = nr_to_free = 0;
                 }
+
                 first_init_pfn = max(end_pfn, first_init_pfn);
         }