1 files changed, 39 insertions, 20 deletions

diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c
index 1223d927904d..ab27ff750519 100644
--- a/mm/page_cgroup.c
+++ b/mm/page_cgroup.c
@@ -21,7 +21,7 @@ static unsigned long total_usage;
 #if !defined(CONFIG_SPARSEMEM)
 
 
-void __init pgdat_page_cgroup_init(struct pglist_data *pgdat)
+void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
 {
         pgdat->node_page_cgroup = NULL;
 }
@@ -49,6 +49,9 @@ static int __init alloc_node_page_cgroup(int nid)
         start_pfn = NODE_DATA(nid)->node_start_pfn;
         nr_pages = NODE_DATA(nid)->node_spanned_pages;
 
+        if (!nr_pages)
+                return 0;
+
         table_size = sizeof(struct page_cgroup) * nr_pages;
 
         base = __alloc_bootmem_node_nopanic(NODE_DATA(nid),
@@ -97,7 +100,8 @@ struct page_cgroup *lookup_page_cgroup(struct page *page)
         return section->page_cgroup + pfn;
 }
 
-int __meminit init_section_page_cgroup(unsigned long pfn)
+/* __alloc_bootmem...() is protected by !slab_available() */
+int __init_refok init_section_page_cgroup(unsigned long pfn)
 {
         struct mem_section *section;
         struct page_cgroup *base, *pc;
@@ -106,19 +110,29 @@ int __meminit init_section_page_cgroup(unsigned long pfn)
 
         section = __pfn_to_section(pfn);
 
-        if (section->page_cgroup)
-                return 0;
-
-        nid = page_to_nid(pfn_to_page(pfn));
-
-        table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION;
-        if (slab_is_available()) {
-                base = kmalloc_node(table_size, GFP_KERNEL, nid);
-                if (!base)
-                        base = vmalloc_node(table_size, nid);
-        } else {
-                base = __alloc_bootmem_node_nopanic(NODE_DATA(nid), table_size,
+        if (!section->page_cgroup) {
+                nid = page_to_nid(pfn_to_page(pfn));
+                table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION;
+                if (slab_is_available()) {
+                        base = kmalloc_node(table_size, GFP_KERNEL, nid);
+                        if (!base)
+                                base = vmalloc_node(table_size, nid);
+                } else {
+                        base = __alloc_bootmem_node_nopanic(NODE_DATA(nid),
+                                table_size,
                                 PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
+                }
+        } else {
+                /*
+                 * We don't have to allocate page_cgroup again, but
+                 * address of memmap may be changed. So, we have to initialize
+                 * again.
+                 */
+                base = section->page_cgroup + pfn;
+                table_size = 0;
+                /* check address of memmap is changed or not. */
+                if (base->page == pfn_to_page(pfn))
+                        return 0;
         }
 
         if (!base) {
@@ -158,7 +172,7 @@ void __free_page_cgroup(unsigned long pfn)
         }
 }
 
-int online_page_cgroup(unsigned long start_pfn,
+int __meminit online_page_cgroup(unsigned long start_pfn,
                         unsigned long nr_pages,
                         int nid)
 {
@@ -183,7 +197,7 @@ int online_page_cgroup(unsigned long start_pfn,
         return -ENOMEM;
 }
 
-int offline_page_cgroup(unsigned long start_pfn,
+int __meminit offline_page_cgroup(unsigned long start_pfn,
                 unsigned long nr_pages, int nid)
 {
         unsigned long start, end, pfn;
@@ -197,7 +211,7 @@ int offline_page_cgroup(unsigned long start_pfn,
 
 }
 
-static int page_cgroup_callback(struct notifier_block *self,
+static int __meminit page_cgroup_callback(struct notifier_block *self,
                                unsigned long action, void *arg)
 {
         struct memory_notify *mn = arg;
@@ -207,18 +221,23 @@ static int page_cgroup_callback(struct notifier_block *self,
                 ret = online_page_cgroup(mn->start_pfn,
                                    mn->nr_pages, mn->status_change_nid);
                 break;
-        case MEM_CANCEL_ONLINE:
         case MEM_OFFLINE:
                 offline_page_cgroup(mn->start_pfn,
                                 mn->nr_pages, mn->status_change_nid);
                 break;
+        case MEM_CANCEL_ONLINE:
         case MEM_GOING_OFFLINE:
                 break;
         case MEM_ONLINE:
         case MEM_CANCEL_OFFLINE:
                 break;
         }
-        ret = notifier_from_errno(ret);
+
+        if (ret)
+                ret = notifier_from_errno(ret);
+        else
+                ret = NOTIFY_OK;
+
         return ret;
 }
 
@@ -248,7 +267,7 @@ void __init page_cgroup_init(void)
         " want\n");
 }
 
-void __init pgdat_page_cgroup_init(struct pglist_data *pgdat)
+void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat)
 {
         return;
 }