taglinefilesource code
send_tail613net/inet/af_inet.csk->send_tail = NULL;
send_tail1741net/inet/ip.csk->send_tail = skb;
send_tail1746net/inet/ip.csk->send_tail->link3 = skb;
send_tail1747net/inet/ip.csk->send_tail = skb;
send_tail93net/inet/sock.hstruct sk_buff    * volatile send_tail;
send_tail1955net/inet/tcp.cnewsk->send_tail = NULL;
send_tail2450net/inet/tcp.csk->send_tail = skb;
send_tail2463net/inet/tcp.csk->send_tail = skb;
send_tail2557net/inet/tcp.csk->send_tail = NULL;
send_tail2589net/inet/tcp.csk->send_tail = skb;
send_tail2593net/inet/tcp.csk->send_tail->link3 = skb;
send_tail2594net/inet/tcp.csk->send_tail = skb;
send_tail2602net/inet/tcp.cif (sk->send_tail == NULL || sk->send_head == NULL) 
send_tail2605net/inet/tcp.csk->send_tail = NULL;
send_tail2776net/inet/tcp.csk->send_tail = NULL;