1.Initial process
2.Create Namespace
fork(fork.c) -> do_fork(fork.c) -> copy_process(fork.c) -> copy_namespaces(nsproxy.c) -> create_new_namespaces(nsproxy.c) -> copy_net_ns(net_namespace.c) ->setup_net(net_namespace.c init networkspace)
3.Receive package( TCP package)
driver(xx-driver) -> netif_rx (dev.c) -> enqueue_to_backlog(dev.c) -> process_backlog(dev.c) -> __netif_receive_skb(dev.c) -> __netif_receive_skb_core(dev.c [handle_ing -> ing_filter -> qdisc_enqueue_root ]) -> deliver_skb(dev.c) -> ip_rcv(ip_input.c) -> ip_rcv_finish(ip_input.c) -> ip_route_input_noref(route.c) -> ip_route_input_slow(route.c) -> ip_local_deliver(ip_input.c) -> ip_local_deliver_finish(ip_input.c) -> tcp_v4_rcv(tcp_ipv4.c) -> tcp_v4_do_rcv(tcp_ipv4.c) -> tcp_child_process(tcp_minsocks.c) -> __sk_add_backlog(tcp_minsocks.c)
4.Application -> L4(UDP)
udp_rcv(udp.c) -> __udp4_lib_rcv (udp.c) -> udp_queue_rcv_skb (udp.c) -> __udp_queue_rcv_skb (udp.c) -> sock_queue_rcv_skb(sock.c) -> sock_def_readable [sk_data_ready] (sock.c) -> sock_def_readable (sock.c) -> udp_sendmsg(udp.c)
5.L4 (UDP)-> Application
SYSCALL_DEFINE2[socketall](socket.c) -> SYSCALL_DEFINE3[sendmsg] (socket.c) -> __sys_sendmmsg(socket.c) -> sock_sendmsg(socket.c) -> __sock_sendmsg(socket.c) -> __sock_sendmsg_nosec(socket.c) -> udp_sendmsg(udp.c) -> ip_make_skb(udp.c) -> __ip_make_skb(ip_output.c)
6.Transmit package: hp100-driver
packet_snd(af_packet.c)->dev_queue_xmit(dev.c ->__dev_xmit_skb [TC]) -> dev_hard_start_xmit(dev.c) -> hp100_start_xmit (hp100.c)-> hp100_start_interface(hp100.c)
7.TC routine: htb
qdisc_enqueue_root(sch_generic.h) -> qdisc_enqueue(sch_generic.h) -> htb_enqueue(sch_htb.c) ->htb_classify(sch_htb.c) -> flow_classify(cls_flow.c) -> tcf_exts_exec(pkt_cls.h) ->tcf_action_exec(act_api.c) -> tcf_act_police(act_police.c)
8. Linux Bridge（Bridge配置IP可进三层路由）：
br_add_if(br_if.c) -> br_handle_frame(br_input.c) -> br_handle_frame_finish(br_input.c) -> br_pass_frame_up(br_input.c) -> netif_receive_skb(dev.c)