memory hotplug: memmap_init_zone called twice

__add_zone calls memmap_init_zone twice if memory gets attached to an empty
zone.  Once via init_currently_empty_zone and once explictly right after that
call.

Looks like this is currently not a bug, however the call is superfluous and
might lead to subtle bugs if memmap_init_zone gets changed.  So make sure it
is called only once.

Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index b17dca7..988bd91 100644 (file)
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -167,13 +167,9 @@ static int __add_zone(struct zone *zone, unsigned long phys_start_pfn)
        int zone_type;
 
        zone_type = zone - pgdat->node_zones;
-       if (!zone->wait_table) {
-               int ret = 0;
-               ret = init_currently_empty_zone(zone, phys_start_pfn,
-                                               nr_pages, MEMMAP_HOTPLUG);
-               if (ret < 0)
-                       return ret;
-       }
+       if (!zone->wait_table)
+               return init_currently_empty_zone(zone, phys_start_pfn,
+                                                nr_pages, MEMMAP_HOTPLUG);
        memmap_init_zone(nr_pages, nid, zone_type,
                         phys_start_pfn, MEMMAP_HOTPLUG);
        return 0;