QUEUE_GET_HEAD
packet = (p_tx_sw_packet_t)QUEUE_GET_HEAD(&tx_ring->used_list);
QUEUE_GET_HEAD(&rx_data->recv_list);
packet = (p_tx_sw_packet_t)QUEUE_GET_HEAD(&tx_ring->used_list);
(p_tx_sw_packet_t)QUEUE_GET_HEAD(&tx_ring->used_list)) != NULL) {
packet = (p_tx_sw_packet_t)QUEUE_GET_HEAD(&pending_list);
packet = (p_tx_sw_packet_t)QUEUE_GET_HEAD(&pending_list);
first_packet = (p_tx_sw_packet_t)QUEUE_GET_HEAD(pending_list);
packet = (p_tx_sw_packet_t)QUEUE_GET_HEAD(pending_list);