Re: [Qemu-devel] [PATCH v3 4/5] KVM: ioeventfd for virtio-ccw devices.

Stefan Hajnoczi
2013-02-26T14:20:58Z

On Tue, Feb 26, 2013 at 12:55:36PM +0200, Michael S. Tsirkin wrote:
> On Mon, Feb 25, 2013 at 04:27:49PM +0100, Cornelia Huck wrote:
> > diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
> > index f0ced1a..8de3cd7 100644
> > --- a/virt/kvm/eventfd.c
> > +++ b/virt/kvm/eventfd.c
> > @@ -679,11 +679,16 @@ static int
> > kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
> > {
> > int pio = args->flags & KVM_IOEVENTFD_FLAG_PIO;
> > - enum kvm_bus bus_idx = pio ? KVM_PIO_BUS : KVM_MMIO_BUS;
> > + int ccw;
> > + enum kvm_bus bus_idx;
> > struct _ioeventfd *p;
> > struct eventfd_ctx *eventfd;
> > int ret;
> >
> > + ccw = args->flags & KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY;
> > + bus_idx = pio ? KVM_PIO_BUS :
> > + ccw ? KVM_VIRTIO_CCW_NOTIFY_BUS :
> > + KVM_MMIO_BUS;
>
> May be better to rewrite using if/else.

Saw this after sending my comment. I agree with Michael, an if
statement allows you to drop the locals and capture the bus_idx
conversion in a single place (it could even be a static function to save
duplicating the code in both functions that use it).

Stefan