Re: [Qemu-devel] [PATCH v3 15/15] mirror: follow AioContext change gracefully

[Paolo Bonzini <pbonzini@redhat.com>]

On 13/06/2016 19:05, Stefan Hajnoczi wrote:
> index 80fd3c7..046e95c 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -331,6 +331,8 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
>          mirror_wait_for_io(s);
>      }
>  
> +    block_job_pause_point(&s->common);

I/O can be in-flight here, so your description of the function is not
100% accurate.  I suppose it's okay because s->waiting_for_io is false
at the pause points you specified?

I guess a comment that explains it will do; and apart from this detail,
the patches are really nice.  Or maybe it's just that you scared with
that 00/15 in the cover letter. :->

Paolo

>          cnt = bdrv_get_dirty_count(s->dirty_bitmap);
>          /* s->common.offset contains the number of bytes already processed so
>           * far, cnt is the number of dirty sectors remaining and
> @@ -781,18 +787,38 @@ static void mirror_complete(BlockJob *job, Error **errp)
>      block_job_enter(&s->common);
>  }