Documentation/networking/net_cachelines/tcp_sock.rst

   1 .. SPDX-License-Identifier: GPL-2.0
   2 .. Copyright (C) 2023 Google LLC
   3
   4 =========================================
   5 tcp_sock struct fast path usage breakdown
   6 =========================================
   7
   8 Type                          Name                    fastpath_tx_access  fastpath_rx_access  Comments
   9 ..struct                      ..tcp_sock
  10 struct_inet_connection_sock   inet_conn
  11 u16                           tcp_header_len          read_mostly         read_mostly         tcp_bound_to_half_wnd,tcp_current_mss(tx);tcp_rcv_established(rx)
  12 u16                           gso_segs                read_mostly         -                   tcp_xmit_size_goal
  13 __be32                        pred_flags              read_write          read_mostly         tcp_select_window(tx);tcp_rcv_established(rx)
  14 u64                           bytes_received          -                   read_write          tcp_rcv_nxt_update(rx)
  15 u32                           segs_in                 -                   read_write          tcp_v6_rcv(rx)
  16 u32                           data_segs_in            -                   read_write          tcp_v6_rcv(rx)
  17 u32                           rcv_nxt                 read_mostly         read_write          tcp_cleanup_rbuf,tcp_send_ack,tcp_inq_hint,tcp_transmit_skb,tcp_receive_window(tx);tcp_v6_do_rcv,tcp_rcv_established,tcp_data_queue,tcp_receive_window,tcp_rcv_nxt_update(write)(rx)
  18 u32                           copied_seq              -                   read_mostly         tcp_cleanup_rbuf,tcp_rcv_space_adjust,tcp_inq_hint
  19 u32                           rcv_wup                 -                   read_write          __tcp_cleanup_rbuf,tcp_receive_window,tcp_receive_established
  20 u32                           snd_nxt                 read_write          read_mostly         tcp_rate_check_app_limited,__tcp_transmit_skb,tcp_event_new_data_sent(write)(tx);tcp_rcv_established,tcp_ack,tcp_clean_rtx_queue(rx)
  21 u32                           segs_out                read_write          -                   __tcp_transmit_skb
  22 u32                           data_segs_out           read_write          -                   __tcp_transmit_skb,tcp_update_skb_after_send
  23 u64                           bytes_sent              read_write          -                   __tcp_transmit_skb
  24 u64                           bytes_acked             -                   read_write          tcp_snd_una_update/tcp_ack
  25 u32                           dsack_dups
  26 u32                           snd_una                 read_mostly         read_write          tcp_wnd_end,tcp_urg_mode,tcp_minshall_check,tcp_cwnd_validate(tx);tcp_ack,tcp_may_update_window,tcp_clean_rtx_queue(write),tcp_ack_tstamp(rx)
  27 u32                           snd_sml                 read_write          -                   tcp_minshall_check,tcp_minshall_update
  28 u32                           rcv_tstamp              -                   read_mostly         tcp_ack
  29 u32                           lsndtime                read_write          -                   tcp_slow_start_after_idle_check,tcp_event_data_sent
  30 u32                           last_oow_ack_time
  31 u32                           compressed_ack_rcv_nxt
  32 u32                           tsoffset                read_mostly         read_mostly         tcp_established_options(tx);tcp_fast_parse_options(rx)
  33 struct_list_head              tsq_node                -                   -
  34 struct_list_head              tsorted_sent_queue      read_write          -                   tcp_update_skb_after_send
  35 u32                           snd_wl1                 -                   read_mostly         tcp_may_update_window
  36 u32                           snd_wnd                 read_mostly         read_mostly         tcp_wnd_end,tcp_tso_should_defer(tx);tcp_fast_path_on(rx)
  37 u32                           max_window              read_mostly         -                   tcp_bound_to_half_wnd,forced_push
  38 u32                           mss_cache               read_mostly         read_mostly         tcp_rate_check_app_limited,tcp_current_mss,tcp_sync_mss,tcp_sndbuf_expand,tcp_tso_should_defer(tx);tcp_update_pacing_rate,tcp_clean_rtx_queue(rx)
  39 u32                           window_clamp            read_mostly         read_write          tcp_rcv_space_adjust,__tcp_select_window
  40 u32                           rcv_ssthresh            read_mostly         -                   __tcp_select_window
  41 u8                            scaling_ratio           read_mostly         read_mostly         tcp_win_from_space
  42 struct                        tcp_rack
  43 u16                           advmss                  -                   read_mostly         tcp_rcv_space_adjust
  44 u8                            compressed_ack
  45 u8:2                          dup_ack_counter
  46 u8:1                          tlp_retrans
  47 u8:1                          tcp_usec_ts             read_mostly         read_mostly
  48 u32                           chrono_start            read_write          -                   tcp_chrono_start/stop(tcp_write_xmit,tcp_cwnd_validate,tcp_send_syn_data)
  49 u32[3]                        chrono_stat             read_write          -                   tcp_chrono_start/stop(tcp_write_xmit,tcp_cwnd_validate,tcp_send_syn_data)
  50 u8:2                          chrono_type             read_write          -                   tcp_chrono_start/stop(tcp_write_xmit,tcp_cwnd_validate,tcp_send_syn_data)
  51 u8:1                          rate_app_limited        -                   read_write          tcp_rate_gen
  52 u8:1                          fastopen_connect
  53 u8:1                          fastopen_no_cookie
  54 u8:1                          is_sack_reneg           -                   read_mostly         tcp_skb_entail,tcp_ack
  55 u8:2                          fastopen_client_fail
  56 u8:4                          nonagle                 read_write          -                   tcp_skb_entail,tcp_push_pending_frames
  57 u8:1                          thin_lto
  58 u8:1                          recvmsg_inq
  59 u8:1                          repair                  read_mostly         -                   tcp_write_xmit
  60 u8:1                          frto
  61 u8                            repair_queue            -                   -
  62 u8:2                          save_syn
  63 u8:1                          syn_data
  64 u8:1                          syn_fastopen
  65 u8:1                          syn_fastopen_exp
  66 u8:1                          syn_fastopen_ch
  67 u8:1                          syn_data_acked
  68 u8:1                          is_cwnd_limited         read_mostly         -                   tcp_cwnd_validate,tcp_is_cwnd_limited
  69 u32                           tlp_high_seq            -                   read_mostly         tcp_ack
  70 u32                           tcp_tx_delay
  71 u64                           tcp_wstamp_ns           read_write          -                   tcp_pacing_check,tcp_tso_should_defer,tcp_update_skb_after_send
  72 u64                           tcp_clock_cache         read_write          read_write          tcp_mstamp_refresh(tcp_write_xmit/tcp_rcv_space_adjust),__tcp_transmit_skb,tcp_tso_should_defer;timer
  73 u64                           tcp_mstamp              read_write          read_write          tcp_mstamp_refresh(tcp_write_xmit/tcp_rcv_space_adjust)(tx);tcp_rcv_space_adjust,tcp_rate_gen,tcp_clean_rtx_queue,tcp_ack_update_rtt/tcp_time_stamp(rx);timer
  74 u32                           srtt_us                 read_mostly         read_write          tcp_tso_should_defer(tx);tcp_update_pacing_rate,__tcp_set_rto,tcp_rtt_estimator(rx)
  75 u32                           mdev_us                 read_write          -                   tcp_rtt_estimator
  76 u32                           mdev_max_us
  77 u32                           rttvar_us               -                   read_mostly         __tcp_set_rto
  78 u32                           rtt_seq                 read_write                              tcp_rtt_estimator
  79 struct_minmax                 rtt_min                 -                   read_mostly         tcp_min_rtt/tcp_rate_gen,tcp_min_rtttcp_update_rtt_min
  80 u32                           packets_out             read_write          read_write          tcp_packets_in_flight(tx/rx);tcp_slow_start_after_idle_check,tcp_nagle_check,tcp_rate_skb_sent,tcp_event_new_data_sent,tcp_cwnd_validate,tcp_write_xmit(tx);tcp_ack,tcp_clean_rtx_queue,tcp_update_pacing_rate(rx)
  81 u32                           retrans_out             -                   read_mostly         tcp_packets_in_flight,tcp_rate_check_app_limited
  82 u32                           max_packets_out         -                   read_write          tcp_cwnd_validate
  83 u32                           cwnd_usage_seq          -                   read_write          tcp_cwnd_validate
  84 u16                           urg_data                -                   read_mostly         tcp_fast_path_check
  85 u8                            ecn_flags               read_write          -                   tcp_ecn_send
  86 u8                            keepalive_probes
  87 u32                           reordering              read_mostly         -                   tcp_sndbuf_expand
  88 u32                           reord_seen
  89 u32                           snd_up                  read_write          read_mostly         tcp_mark_urg,tcp_urg_mode,__tcp_transmit_skb(tx);tcp_clean_rtx_queue(rx)
  90 struct_tcp_options_received   rx_opt                  read_mostly         read_write          tcp_established_options(tx);tcp_fast_path_on,tcp_ack_update_window,tcp_is_sack,tcp_data_queue,tcp_rcv_established,tcp_ack_update_rtt(rx)
  91 u32                           snd_ssthresh            -                   read_mostly         tcp_update_pacing_rate
  92 u32                           snd_cwnd                read_mostly         read_mostly         tcp_snd_cwnd,tcp_rate_check_app_limited,tcp_tso_should_defer(tx);tcp_update_pacing_rate
  93 u32                           snd_cwnd_cnt
  94 u32                           snd_cwnd_clamp
  95 u32                           snd_cwnd_used
  96 u32                           snd_cwnd_stamp
  97 u32                           prior_cwnd
  98 u32                           prr_delivered
  99 u32                           prr_out                 read_mostly         read_mostly         tcp_rate_skb_sent,tcp_newly_delivered(tx);tcp_ack,tcp_rate_gen,tcp_clean_rtx_queue(rx)
 100 u32                           delivered               read_mostly         read_write          tcp_rate_skb_sent, tcp_newly_delivered(tx);tcp_ack, tcp_rate_gen, tcp_clean_rtx_queue (rx)
 101 u32                           delivered_ce            read_mostly         read_write          tcp_rate_skb_sent(tx);tcp_rate_gen(rx)
 102 u32                           lost                    -                   read_mostly         tcp_ack
 103 u32                           app_limited             read_write          read_mostly         tcp_rate_check_app_limited,tcp_rate_skb_sent(tx);tcp_rate_gen(rx)
 104 u64                           first_tx_mstamp         read_write          -                   tcp_rate_skb_sent
 105 u64                           delivered_mstamp        read_write          -                   tcp_rate_skb_sent
 106 u32                           rate_delivered          -                   read_mostly         tcp_rate_gen
 107 u32                           rate_interval_us        -                   read_mostly         rate_delivered,rate_app_limited
 108 u32                           rcv_wnd                 read_write          read_mostly         tcp_select_window,tcp_receive_window,tcp_fast_path_check
 109 u32                           write_seq               read_write          -                   tcp_rate_check_app_limited,tcp_write_queue_empty,tcp_skb_entail,forced_push,tcp_mark_push
 110 u32                           notsent_lowat           read_mostly         -                   tcp_stream_memory_free
 111 u32                           pushed_seq              read_write          -                   tcp_mark_push,forced_push
 112 u32                           lost_out                read_mostly         read_mostly         tcp_left_out(tx);tcp_packets_in_flight(tx/rx);tcp_rate_check_app_limited(rx)
 113 u32                           sacked_out              read_mostly         read_mostly         tcp_left_out(tx);tcp_packets_in_flight(tx/rx);tcp_clean_rtx_queue(rx)
 114 struct_hrtimer                pacing_timer
 115 struct_hrtimer                compressed_ack_timer
 116 struct_sk_buff*               lost_skb_hint           read_mostly                             tcp_clean_rtx_queue
 117 struct_sk_buff*               retransmit_skb_hint     read_mostly         -                   tcp_clean_rtx_queue
 118 struct_rb_root                out_of_order_queue      -                   read_mostly         tcp_data_queue,tcp_fast_path_check
 119 struct_sk_buff*               ooo_last_skb
 120 struct_tcp_sack_block[1]      duplicate_sack
 121 struct_tcp_sack_block[4]      selective_acks
 122 struct_tcp_sack_block[4]      recv_sack_cache
 123 struct_sk_buff*               highest_sack            read_write          -                   tcp_event_new_data_sent
 124 int                           lost_cnt_hint
 125 u32                           prior_ssthresh
 126 u32                           high_seq
 127 u32                           retrans_stamp
 128 u32                           undo_marker
 129 int                           undo_retrans
 130 u64                           bytes_retrans
 131 u32                           total_retrans
 132 u32                           rto_stamp
 133 u16                           total_rto
 134 u16                           total_rto_recoveries
 135 u32                           total_rto_time
 136 u32                           urg_seq                 -                   -
 137 unsigned_int                  keepalive_time
 138 unsigned_int                  keepalive_intvl
 139 int                           linger2
 140 u8                            bpf_sock_ops_cb_flags
 141 u8:1                          bpf_chg_cc_inprogress
 142 u16                           timeout_rehash
 143 u32                           rcv_ooopack
 144 u32                           rcv_rtt_last_tsecr
 145 struct                        rcv_rtt_est             -                   read_write          tcp_rcv_space_adjust,tcp_rcv_established
 146 struct                        rcvq_space              -                   read_write          tcp_rcv_space_adjust
 147 struct                        mtu_probe
 148 u32                           plb_rehash
 149 u32                           mtu_info
 150 bool                          is_mptcp
 151 bool                          smc_hs_congested
 152 bool                          syn_smc
 153 struct_tcp_sock_af_ops*       af_specific
 154 struct_tcp_md5sig_info*       md5sig_info
 155 struct_tcp_fastopen_request*  fastopen_req
 156 struct_request_sock*          fastopen_rsk
 157 struct_saved_syn*             saved_syn