1 files changed, 74 insertions, 57 deletions

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index dd186c1a5d53..c46887b5a11e 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -34,6 +34,23 @@
 
 #include "internal.h"
 
+DEFINE_MUTEX(mem_hotplug_mutex);
+
+void lock_memory_hotplug(void)
+{
+        mutex_lock(&mem_hotplug_mutex);
+
+        /* for exclusive hibernation if CONFIG_HIBERNATION=y */
+        lock_system_sleep();
+}
+
+void unlock_memory_hotplug(void)
+{
+        unlock_system_sleep();
+        mutex_unlock(&mem_hotplug_mutex);
+}
+
+
 /* add this memory to iomem resource */
 static struct resource *register_memory_resource(u64 start, u64 size)
 {
@@ -65,9 +82,10 @@ static void release_memory_resource(struct resource *res)
 
 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 #ifndef CONFIG_SPARSEMEM_VMEMMAP
-static void get_page_bootmem(unsigned long info,  struct page *page, int type)
+static void get_page_bootmem(unsigned long info,  struct page *page,
+                             unsigned long type)
 {
-        atomic_set(&page->_mapcount, type);
+        page->lru.next = (struct list_head *) type;
         SetPagePrivate(page);
         set_page_private(page, info);
         atomic_inc(&page->_count);
@@ -77,15 +95,16 @@ static void get_page_bootmem(unsigned long info,  struct page *page, int type)
  * so use __ref to tell modpost not to generate a warning */
 void __ref put_page_bootmem(struct page *page)
 {
-        int type;
+        unsigned long type;
 
-        type = atomic_read(&page->_mapcount);
-        BUG_ON(type >= -1);
+        type = (unsigned long) page->lru.next;
+        BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
+               type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
 
         if (atomic_dec_return(&page->_count) == 1) {
                 ClearPagePrivate(page);
                 set_page_private(page, 0);
-                reset_page_mapcount(page);
+                INIT_LIST_HEAD(&page->lru);
                 __free_pages_bootmem(page, 0);
         }
 
@@ -355,10 +374,6 @@ void online_page(struct page *page)
                 totalhigh_pages++;
 #endif
 
-#ifdef CONFIG_FLATMEM
-        max_mapnr = max(page_to_pfn(page), max_mapnr);
-#endif
-
         ClearPageReserved(page);
         init_page_count(page);
         __free_page(page);
@@ -381,7 +396,7 @@ static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
 }
 
 
-int online_pages(unsigned long pfn, unsigned long nr_pages)
+int __ref online_pages(unsigned long pfn, unsigned long nr_pages)
 {
         unsigned long onlined_pages = 0;
         struct zone *zone;
@@ -390,6 +405,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
         int ret;
         struct memory_notify arg;
 
+        lock_memory_hotplug();
         arg.start_pfn = pfn;
         arg.nr_pages = nr_pages;
         arg.status_change_nid = -1;
@@ -402,6 +418,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
         ret = notifier_to_errno(ret);
         if (ret) {
                 memory_notify(MEM_CANCEL_ONLINE, &arg);
+                unlock_memory_hotplug();
                 return ret;
         }
         /*
@@ -426,6 +443,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
                 printk(KERN_DEBUG "online_pages %lx at %lx failed\n",
                         nr_pages, pfn);
                 memory_notify(MEM_CANCEL_ONLINE, &arg);
+                unlock_memory_hotplug();
                 return ret;
         }
 
@@ -437,8 +455,9 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
                 zone_pcp_update(zone);
 
         mutex_unlock(&zonelists_mutex);
-        setup_per_zone_wmarks();
-        calculate_zone_inactive_ratio(zone);
+
+        init_per_zone_wmark_min();
+
         if (onlined_pages) {
                 kswapd_run(zone_to_nid(zone));
                 node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
@@ -450,6 +469,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
 
         if (onlined_pages)
                 memory_notify(MEM_ONLINE, &arg);
+        unlock_memory_hotplug();
 
         return 0;
 }
@@ -474,6 +494,14 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
         /* init node's zones as empty zones, we don't have any present pages.*/
         free_area_init_node(nid, zones_size, start_pfn, zholes_size);
 
+        /*
+         * The node we allocated has no zone fallback lists. For avoiding
+         * to access not-initialized zonelist, build here.
+         */
+        mutex_lock(&zonelists_mutex);
+        build_all_zonelists(NULL);
+        mutex_unlock(&zonelists_mutex);
+
         return pgdat;
 }
 
@@ -493,9 +521,9 @@ int mem_online_node(int nid)
         pg_data_t       *pgdat;
         int     ret;
 
-        lock_system_sleep();
+        lock_memory_hotplug();
         pgdat = hotadd_new_pgdat(nid, 0);
-        if (pgdat) {
+        if (!pgdat) {
                 ret = -ENOMEM;
                 goto out;
         }
@@ -504,7 +532,7 @@ int mem_online_node(int nid)
         BUG_ON(ret);
 
 out:
-        unlock_system_sleep();
+        unlock_memory_hotplug();
         return ret;
 }
 
@@ -516,7 +544,7 @@ int __ref add_memory(int nid, u64 start, u64 size)
         struct resource *res;
         int ret;
 
-        lock_system_sleep();
+        lock_memory_hotplug();
 
         res = register_memory_resource(start, size);
         ret = -EEXIST;
@@ -563,7 +591,7 @@ error:
                 release_memory_resource(res);
 
 out:
-        unlock_system_sleep();
+        unlock_memory_hotplug();
         return ret;
 }
 EXPORT_SYMBOL_GPL(add_memory);
@@ -602,27 +630,14 @@ static struct page *next_active_pageblock(struct page *page)
 /* Checks if this range of memory is likely to be hot-removable. */
 int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
 {
-        int type;
         struct page *page = pfn_to_page(start_pfn);
         struct page *end_page = page + nr_pages;
 
         /* Check the starting page of each pageblock within the range */
         for (; page < end_page; page = next_active_pageblock(page)) {
-                type = get_pageblock_migratetype(page);
-
-                /*
-                 * A pageblock containing MOVABLE or free pages is considered
-                 * removable
-                 */
-                if (type != MIGRATE_MOVABLE && !pageblock_free(page))
-                        return 0;
-
-                /*
-                 * A pageblock starting with a PageReserved page is not
-                 * considered removable.
-                 */
-                if (PageReserved(page))
+                if (!is_pageblock_removable_nolock(page))
                         return 0;
+                cond_resched();
         }
 
         /* All pageblocks in the memory block are likely to be hot-removable */
@@ -659,7 +674,7 @@ static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
  * Scanning pfn is much easier than scanning lru list.
  * Scan pfn from start to end and Find LRU page.
  */
-int scan_lru_pages(unsigned long start, unsigned long end)
+static unsigned long scan_lru_pages(unsigned long start, unsigned long end)
 {
         unsigned long pfn;
         struct page *page;
@@ -695,7 +710,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
                 if (!pfn_valid(pfn))
                         continue;
                 page = pfn_to_page(pfn);
-                if (!page_count(page))
+                if (!get_page_unless_zero(page))
                         continue;
                 /*
                  * We can skip free pages. And we can only deal with pages on
@@ -703,35 +718,39 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
                  */
                 ret = isolate_lru_page(page);
                 if (!ret) { /* Success */
+                        put_page(page);
                         list_add_tail(&page->lru, &source);
                         move_pages--;
                         inc_zone_page_state(page, NR_ISOLATED_ANON +
                                             page_is_file_cache(page));
 
                 } else {
-                        /* Becasue we don't have big zone->lock. we should
-                           check this again here. */
-                        if (page_count(page))
-                                not_managed++;
 #ifdef CONFIG_DEBUG_VM
                         printk(KERN_ALERT "removing pfn %lx from LRU failed\n",
                                pfn);
                         dump_page(page);
 #endif
+                        put_page(page);
+                        /* Because we don't have big zone->lock. we should
+                           check this again here. */
+                        if (page_count(page)) {
+                                not_managed++;
+                                ret = -EBUSY;
+                                break;
+                        }
                 }
         }
-        ret = -EBUSY;
-        if (not_managed) {
-                if (!list_empty(&source))
+        if (!list_empty(&source)) {
+                if (not_managed) {
+                        putback_lru_pages(&source);
+                        goto out;
+                }
+                /* this function returns # of failed pages */
+                ret = migrate_pages(&source, hotremove_migrate_alloc, 0,
+                                                                true, true);
+                if (ret)
                         putback_lru_pages(&source);
-                goto out;
         }
-        ret = 0;
-        if (list_empty(&source))
-                goto out;
-        /* this function returns # of failed pages */
-        ret = migrate_pages(&source, hotremove_migrate_alloc, 0, 1);
-
 out:
         return ret;
 }
@@ -783,7 +802,7 @@ check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
         return offlined;
 }
 
-static int offline_pages(unsigned long start_pfn,
+static int __ref offline_pages(unsigned long start_pfn,
                   unsigned long end_pfn, unsigned long timeout)
 {
         unsigned long pfn, nr_pages, expire;
@@ -803,7 +822,7 @@ static int offline_pages(unsigned long start_pfn,
         if (!test_pages_in_a_zone(start_pfn, end_pfn))
                 return -EINVAL;
 
-        lock_system_sleep();
+        lock_memory_hotplug();
 
         zone = page_zone(pfn_to_page(start_pfn));
         node = zone_to_nid(zone);
@@ -840,7 +859,6 @@ repeat:
         ret = 0;
         if (drain) {
                 lru_add_drain_all();
-                flush_scheduled_work();
                 cond_resched();
                 drain_all_pages();
         }
@@ -862,7 +880,6 @@ repeat:
         }
         /* drain all zone's lru pagevec, this is asyncronous... */
         lru_add_drain_all();
-        flush_scheduled_work();
         yield();
         /* drain pcp pages , this is synchrouns. */
         drain_all_pages();
@@ -883,8 +900,8 @@ repeat:
         zone->zone_pgdat->node_present_pages -= offlined_pages;
         totalram_pages -= offlined_pages;
 
-        setup_per_zone_wmarks();
-        calculate_zone_inactive_ratio(zone);
+        init_per_zone_wmark_min();
+
         if (!node_present_pages(node)) {
                 node_clear_state(node, N_HIGH_MEMORY);
                 kswapd_stop(node);
@@ -894,7 +911,7 @@ repeat:
         writeback_set_ratelimit();
 
         memory_notify(MEM_OFFLINE, &arg);
-        unlock_system_sleep();
+        unlock_memory_hotplug();
         return 0;
 
 failed_removal:
@@ -905,7 +922,7 @@ failed_removal:
         undo_isolate_page_range(start_pfn, end_pfn);
 
 out:
-        unlock_system_sleep();
+        unlock_memory_hotplug();
         return ret;
 }