tcp_rtx_and_write_queues_empty
first_skb = tcp_rtx_and_write_queues_empty(sk);
if (unlikely(tcp_rtx_and_write_queues_empty(sk) && err == -EAGAIN)) {
if (tcp_rtx_and_write_queues_empty(sk))
if (!tcp_rtx_and_write_queues_empty(ssk)) {
if (!tcp_rtx_and_write_queues_empty(ssk)) {