[Qemu-devel] [PATCH 1/2] migration: bitmap_set is unnecessary as bitmap_new uses g_try_malloc0

["Denis V. Lunev" <den@openvz.org>]

we can omit calling of bitmap_set in migration_bitmap_extend and
ram_save_setup just after bitmap_new, which properly zeroes memory
inside.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Igor Redko <redkoi@virtuozzo.com>
CC: Anna Melekhova <annam@virtuozzo.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Amit Shah <amit.shah@redhat.com>
CC: Wen Congyang <wency@cn.fujitsu.com>
---
 migration/ram.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/migration/ram.c b/migration/ram.c
index 7f007e6..a712c68 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1081,7 +1081,6 @@ void migration_bitmap_extend(ram_addr_t old, ram_addr_t new)
          */
         qemu_mutex_lock(&migration_bitmap_mutex);
         bitmap_copy(bitmap, old_bitmap, old);
-        bitmap_set(bitmap, old, new - old);
         atomic_rcu_set(&migration_bitmap, bitmap);
         qemu_mutex_unlock(&migration_bitmap_mutex);
         migration_dirty_pages += new - old;
@@ -1146,7 +1145,6 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
 
     ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS;
     migration_bitmap = bitmap_new(ram_bitmap_pages);
-    bitmap_set(migration_bitmap, 0, ram_bitmap_pages);
 
     /*
      * Count the total number of pages used by ram blocks not including any
-- 
2.1.4