Re: [Qemu-devel] [QEMU 1/7] balloon: speed up inflating & deflating process

[Li, Liang Z]

> >
> >          virtqueue_push(vq, elem, offset); @@ -374,6 +489,7 @@ static
> > uint64_t virtio_balloon_get_features(VirtIODevice *vdev, uint64_t f,
> >      VirtIOBalloon *dev = VIRTIO_BALLOON(vdev);
> >      f |= dev->host_features;
> >      virtio_add_feature(&f, VIRTIO_BALLOON_F_STATS_VQ);
> > +    virtio_add_feature(&f, VIRTIO_BALLOON_F_PAGE_BITMAP);
> >      return f;
> >  }
> >
> 
> Pls add features to virtio_balloon_properties.
> You also need to handle compatibility by disabling for old machine types.
> 

I forgot that, will add in next version.

> > --- a/include/standard-headers/linux/virtio_balloon.h
> > +++ b/include/standard-headers/linux/virtio_balloon.h
> > @@ -34,6 +34,7 @@
> >  #define VIRTIO_BALLOON_F_MUST_TELL_HOST    0 /* Tell before
> reclaiming pages */
> >  #define VIRTIO_BALLOON_F_STATS_VQ  1 /* Memory Stats virtqueue
> */
> >  #define VIRTIO_BALLOON_F_DEFLATE_ON_OOM    2 /* Deflate balloon
> on OOM */
> > +#define VIRTIO_BALLOON_F_PAGE_BITMAP  3 /* Use page bitmap to
> send
> > +page info */
> >
> >  /* Size of a PFN in the balloon interface. */  #define
> > VIRTIO_BALLOON_PFN_SHIFT 12
> 
> We want to keep this in sync with Linux.
> Let's get a minimal patch to extend this header merged in linux, then update
> this one.

OK. Can this be independent of the virtio-balloon SPEC? As I understand it,
 it will not get merged before the SPEC is set?

Thanks!
Liang