sys_bind
-> inet_bind
-> inet_csk_get_port
-> goto have_snum:
-> goto tb_not_found: tb == NULL
-> inet_bind_bucket_create
-> goto success:
-> inet_bind_hash
-> sk_add_bind_node
-> fput_light
sys_listen
-> inet_listen
-> inet_csk_listen_start
-> reqsk_queue_alloc
-> inet_csk_delack_init
-> set sk->sk_state = TCP_LISTEN
-> inet_csk_get_port
-> goto have_snum:
-> goto tb_found:
-> inet_csk_bind_conflict
-> goto tb_not_found: tb != NULL
-> inet_hash
-> __inet_hash // tcp_hashinfo.listening_hash[X] add node
tcp_v4_rcv
-> __inet_lookup_skb
-> __inet_lookup
-> __inet_lookup_established
-> __inet_lookup_listener // found
-> tcp_v4_do_rcv // sk_state == TCP_LISTEN
-> tcp_rcv_state_process
-> tcp_v4_conn_request // icsk->icsk_af_ops->conn_request
-> tcp_conn_request
-> req = inet_reqsk_alloc
-> reqsk_alloc
req->rsk_listener = sk_listener;
ireq->ireq_state = TCP_NEW_SYN_RECV;
-> tcp_parse_options
-> tcp_openreq_init
-> tcp_v4_init_req // af_ops->init_req
-> tcp_v4_save_options
-> tcp_v4_init_sequence // af_ops->init_seq
-> tcp_v4_route_req // af_ops->route_req
-> inet_csk_route_req
-> flowi4_init_output
-> ip_route_output_flow
-> tcp_ecn_create_request
-> tcp_reqsk_record_syn
-> inet_csk_reqsk_queue_hash_add
-> reqsk_queue_hash_req
-> inet_ehash_insert
-> __sk_nulls_add_node_rcu
-> inet_csk_reqsk_queue_added
-> tcp_v4_send_synack // af_ops->send_synack
-> tcp_make_synack
-> __tcp_v4_send_check
-> ip_build_and_send_pkt
-> ip_local_out
-> __ip_local_out
-> dst_output
-> ip_output
tcp_v4_rcv
-> __inet_lookup_skb
-> __inet_lookup
-> __inet_lookup_established // found
-> sk->sk_state == TCP_NEW_SYN_RECV
-> tcp_check_req
-> tcp_parse_options
-> tcp_paws_reject
-> tcp_in_window
-> tcp_v4_syn_recv_sock // inet_csk(sk)->icsk_af_ops->syn_recv_sock
-> tcp_create_openreq_child
-> inet_csk_clone_lock
-> sk_clone_lock
-> sk_prot_alloc
-> tcp_init_xmit_timers
-> inet_sk_rx_dst_set
-> inet_csk_route_child_sock
-> tcp_ca_openreq_child
-> tcp_assign_congestion_control
-> tcp_set_ca_state TCP_CA_Open
-> bictcp_state
-> tcp_sync_mss -> dst_mtu -> ipv4_mtu
-> tcp_mtu_to_mss
-> tcp_bound_to_half_wnd
-> dst_metric_advmss -> ipv4_default_advmss
-> tcp_initialize_rcv_mss
-> __inet_inherit_port -> inet_bind_hash
-> inet_ehash_nolisten
-> inet_ehash_insert
-> sk_nulls_del_node_init_rcu
-> __sk_nulls_add_node_rcu
-> sock_prot_inuse_add
-> tcp_move_syn
-> sock_rps_save_rxhash
-> tcp_synack_rtt_meas
-> skb_mstamp_us_delta
-> tcp_ack_update_rtt
-> tcp_update_rtt_min
-> tcp_rtt_estimator
-> tcp_set_rto
-> inet_csk_complete_hashdance
-> inet_csk_reqsk_queue_drop
-> reqsk_queue_removed
-> inet_csk_reqsk_queue_add
-> sk_acceptq_added
-> tcp_child_process
-> tcp_rcv_state_process
-> tcp_validate_incoming
-> tcp_ack
-> tcp_ack_update_window
-> tcp_ecn_rcv_ecn_echo // false
-> tcp_in_ack_event
return 1
-> sk_state == TCP_SYN_RECV
-> inet_sk_rebuild_header // icsk->icsk_af_ops->rebuild_header
-> tcp_init_congestion_control -> bictcp_init
-> tcp_mtup_init
-> tcp_init_buffer_space
-> tcp_fixup_rcvbuf
-> tcp_sndbuf_expand
-> tcp_full_space
TCP_ESTABLISHED
sk->sk_state_change -> sock_def_wakeup
-> tcp_init_metrics
-> tcp_update_pacing_rate
-> tcp_initialize_rcv_mss
-> tcp_fast_path_on
// out of switch
-> tcp_urg
// switch TCP_ESTABLISHED
-> tcp_data_queue
-> tcp_data_snd_check
-> tcp_ack_snd_check
-> parent->sk_data_ready -> sock_def_readable -> wake_up_interruptible_sync_poll
