Re: [PATCH 1/2] virtio_balloon: fix pages_to_free calculation

[Wei Wang]

On 11/19/2019 07:08 AM, Michael S. Tsirkin wrote:
> So I really think we should do something like the below instead.
> Limit playing with balloon pages so we can gradually limit it to legacy.
> Testing, review would be appreciated.
>
> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
>
>
> diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
> index 226fbb995fb0..7cee05cdf3fb 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -772,6 +772,13 @@ static unsigned long shrink_free_pages(struct virtio_balloon *vb,
>   	return blocks_freed << VIRTIO_BALLOON_FREE_PAGE_ORDER;
>   }
>   
> +static unsigned long leak_balloon_pages(struct virtio_balloon *vb,
> +                                          unsigned long pages_to_free)
> +{
> +	return leak_balloon(vb, pages_to_free * VIRTIO_BALLOON_PAGES_PER_PAGE) /
> +		VIRTIO_BALLOON_PAGES_PER_PAGE;
> +}
> +

Looks good to me, too. (just a reminder that the returning type of 
leak_balloon is "unsigned int",
we may want them to be consistent).

Reviewed-by: Wei Wang <wei.w.wang@xxxxxxxxx>

Best,
Wei