sdp_tx_ring_slots_left
likely(sdp_tx_ring_slots_left(ssk));
if (sdp_tx_ring_slots_left(ssk) < SDP_TX_SIZE / 2)
sdp_tx_ring_slots_left(ssk)) {
sdp_tx_ring_slots_left(ssk) && sk->so_snd.sb_sndptr &&
sdp_tx_ring_slots_left(ssk) && (mb = sk->so_snd.sb_sndptr) &&
low = (sdp_tx_ring_slots_left(ssk) <= SDP_MIN_TX_CREDITS);