Re: [Qemu-devel] [PATCH 03/13] virtio: move ioeventfd_started flag to VirtioBusState

[Cornelia Huck <cornelia.huck@de.ibm.com>]

On Mon, 10 Oct 2016 13:53:31 +0200
Paolo Bonzini <pbonzini@redhat.com> wrote:

> This simplifies the code and removes the ioeventfd_started
> and ioeventfd_set_started callback.  The only difference is
> in how virtio-ccw handles an error---it doesn't disable
> ioeventfd forever anymore.  It was the only backend to do
> so, and if desired this behavior should be implemented in
> virtio-bus.c.

I guess this depends on whether we consider failures to be generally
transient or generally permanent. I decided to disable ioeventfd on
failure as I could not think of a transient failure; but in the end, it
does not really matter much, so I'm fine with this change.

> 
> Instead of ioeventfd_started, the ioeventfd_assign callback now
> determines whether the virtio bus supports host notifiers.
> 
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  hw/block/dataplane/virtio-blk.c |  2 +-
>  hw/s390x/virtio-ccw.c           | 21 ---------------------
>  hw/s390x/virtio-ccw.h           |  1 -
>  hw/scsi/virtio-scsi-dataplane.c |  2 +-
>  hw/virtio/vhost.c               |  2 +-
>  hw/virtio/virtio-bus.c          | 14 ++++++--------
>  hw/virtio/virtio-mmio.c         | 18 ------------------
>  hw/virtio/virtio-pci.c          | 17 -----------------
>  hw/virtio/virtio-pci.h          |  1 -
>  include/hw/virtio/virtio-bus.h  | 17 +++++++----------
>  10 files changed, 16 insertions(+), 79 deletions(-)

Nice amount of code deletion :)

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>