vr_npoll
int cpuid = sc->vr_npoll.ifpc_cpuid;
static void vr_npoll(struct ifnet *, struct ifpoll_info *);
ifp->if_npoll = vr_npoll;
ifpoll_compat_setup(&sc->vr_npoll, NULL, NULL, device_get_unit(dev),
struct ifpoll_compat vr_npoll;