ifq_ifqs
if (ifp->if_ifqs != ifp->if_snd.ifq_ifqs) {
KASSERT(ifp->if_ifqs == ifp->if_snd.ifq_ifqs);
ifp->if_snd.ifq_ifqs[0] = &ifp->if_snd;
ifp->if_ifqs = ifp->if_snd.ifq_ifqs;