Re: [Qemu-devel] [PATCH 16/19] block: protect modification of dirty bitmaps with a mutex

[Vladimir Sementsov-Ogievskiy]

26.06.2017 19:54, Paolo Bonzini wrote:
> On 26/06/2017 18:07, Vladimir Sementsov-Ogievskiy wrote:
> > HI!
> >
> > One question here, should not 'bdrv_undo_clear_dirty_bitmap' be under
> > lock too?
> Any call to dirty bitmap functions between bdrv_clear_dirty_bitmap and
> bdrv_undo_clear_dirty_bitmap is problematic anyway, so
> bdrv_clear_dirty_bitmap really only needs the lock in the !out case;
> bdrv_undo_clear_dirty_bitmap is only called when out != NULL.
>
> However, I agree it would be cleaner to add the lock there, too.
>
> Paolo


Also, you've added comment "Called with BQL taken" both to functions 
that calls bdrv_dirty_bitmaps_lock and that do not... What is BQL?


--
Best regards,
Vladimir