On 09/25/2015 05:09 PM, Denis V. Lunev wrote: > we can omit calling of bitmap_set in migration_bitmap_extend and > ram_save_setup just after bitmap_new, which properly zeroes memory > inside.
This patch is wrong. bitmap_set() is set all bits of the memory to 1, not 0. > > Signed-off-by: Denis V. Lunev <d...@openvz.org> > CC: Igor Redko <red...@virtuozzo.com> > CC: Anna Melekhova <an...@virtuozzo.com> > CC: Juan Quintela <quint...@redhat.com> > CC: Amit Shah <amit.s...@redhat.com> > CC: Wen Congyang <we...@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 >
