FXP_USABLE_TXCB
while (!ifq_is_empty(&ifp->if_snd) && sc->tx_queued < FXP_USABLE_TXCB) {
if (sc->tx_queued >= FXP_USABLE_TXCB)
if (sc->tx_queued < FXP_USABLE_TXCB)
if (sc->tx_queued < FXP_USABLE_TXCB)
ifq_set_maxlen(&ifp->if_snd, FXP_USABLE_TXCB);