Merge branch 'accecn-protocol-case-handling-series'

Chia-Yu Chang says:

====================
AccECN protocol case handling series

Plesae find the v13 AccECN case handling patch series, which covers
several excpetional case handling of Accurate ECN spec (RFC9768),
adds new identifiers to be used by CC modules, adds ecn_delta into
rate_sample, and keeps the ACE counter for computation, etc.

This patch series is part of the full AccECN patch series, which is at
https://github.com/L4STeam/linux-net-next/commits/upstream_l4steam/
---
Chia-Yu Chang (13):
  selftests/net: gro: add self-test for TCP CWR flag
  tcp: ECT_1_NEGOTIATION and NEEDS_ACCECN identifiers
  tcp: disable RFC3168 fallback identifier for CC modules
  tcp: accecn: handle unexpected AccECN negotiation feedback
  tcp: accecn: retransmit downgraded SYN in AccECN negotiation
  tcp: add TCP_SYNACK_RETRANS synack_type
  tcp: accecn: retransmit SYN/ACK without AccECN option or non-AccECN
    SYN/ACK
  tcp: accecn: unset ECT if receive or send ACE=0 in AccECN negotiaion
  tcp: accecn: fallback outgoing half link to non-AccECN
  tcp: accecn: detect loss ACK w/ AccECN option and add
    TCP_ACCECN_OPTION_PERSIST
  tcp: accecn: add tcpi_ecn_mode and tcpi_option2 in tcp_info
  tcp: accecn: enable AccECN
  selftests/net: packetdrill: add TCP Accurate ECN cases

Ilpo Järvinen (2):
  tcp: try to avoid safer when ACKs are thinned
  gro: flushing when CWR is set negatively affects AccECN

 Documentation/networking/ip-sysctl.rst        |   4 +-
 .../networking/net_cachelines/tcp_sock.rst    |   1 +
 include/linux/tcp.h                           |   4 +-
 include/net/inet_ecn.h                        |  20 +++-
 include/net/tcp.h                             |  32 +++++-
 include/net/tcp_ecn.h                         | 103 ++++++++++++------
 include/uapi/linux/tcp.h                      |  26 ++++-
 net/ipv4/inet_connection_sock.c               |   3 +
 net/ipv4/sysctl_net_ipv4.c                    |   4 +-
 net/ipv4/tcp.c                                |  10 ++
 net/ipv4/tcp_cong.c                           |   5 +-
 net/ipv4/tcp_input.c                          |  40 ++++++-
 net/ipv4/tcp_minisocks.c                      |  43 +++++---
 net/ipv4/tcp_offload.c                        |   3 +-
 net/ipv4/tcp_output.c                         |  34 ++++--
 net/ipv4/tcp_timer.c                          |   3 +
 tools/testing/selftests/drivers/net/gro.c     |  81 ++++++++++----
 tools/testing/selftests/drivers/net/gro.py    |   3 +-
 .../tcp_accecn_2nd_data_as_first.pkt          |  24 ++++
 .../tcp_accecn_2nd_data_as_first_connect.pkt  |  30 +++++
 .../tcp_accecn_3rd_ack_after_synack_rxmt.pkt  |  19 ++++
 ..._accecn_3rd_ack_ce_updates_received_ce.pkt |  18 +++
 .../tcp_accecn_3rd_ack_lost_data_ce.pkt       |  22 ++++
 .../net/packetdrill/tcp_accecn_3rd_dups.pkt   |  26 +++++
 .../tcp_accecn_acc_ecn_disabled.pkt           |  13 +++
 .../tcp_accecn_accecn_then_notecn_syn.pkt     |  28 +++++
 .../tcp_accecn_accecn_to_rfc3168.pkt          |  18 +++
 .../tcp_accecn_client_accecn_options_drop.pkt |  34 ++++++
 .../tcp_accecn_client_accecn_options_lost.pkt |  38 +++++++
 .../tcp_accecn_clientside_disabled.pkt        |  12 ++
 ...cecn_close_local_close_then_remote_fin.pkt |  25 +++++
 .../tcp_accecn_delivered_2ndlargeack.pkt      |  25 +++++
 ..._accecn_delivered_falseoverflow_detect.pkt |  31 ++++++
 .../tcp_accecn_delivered_largeack.pkt         |  24 ++++
 .../tcp_accecn_delivered_largeack2.pkt        |  25 +++++
 .../tcp_accecn_delivered_maxack.pkt           |  25 +++++
 .../tcp_accecn_delivered_updates.pkt          |  70 ++++++++++++
 .../net/packetdrill/tcp_accecn_ecn3.pkt       |  12 ++
 .../tcp_accecn_ecn_field_updates_opt.pkt      |  35 ++++++
 .../packetdrill/tcp_accecn_ipflags_drop.pkt   |  14 +++
 .../tcp_accecn_listen_opt_drop.pkt            |  16 +++
 .../tcp_accecn_multiple_syn_ack_drop.pkt      |  28 +++++
 .../tcp_accecn_multiple_syn_drop.pkt          |  18 +++
 .../tcp_accecn_negotiation_bleach.pkt         |  23 ++++
 .../tcp_accecn_negotiation_connect.pkt        |  23 ++++
 .../tcp_accecn_negotiation_listen.pkt         |  26 +++++
 .../tcp_accecn_negotiation_noopt_connect.pkt  |  23 ++++
 .../tcp_accecn_negotiation_optenable.pkt      |  23 ++++
 .../tcp_accecn_no_ecn_after_accecn.pkt        |  20 ++++
 .../net/packetdrill/tcp_accecn_noopt.pkt      |  27 +++++
 .../net/packetdrill/tcp_accecn_noprogress.pkt |  27 +++++
 .../tcp_accecn_notecn_then_accecn_syn.pkt     |  28 +++++
 .../tcp_accecn_rfc3168_to_fallback.pkt        |  18 +++
 .../tcp_accecn_rfc3168_to_rfc3168.pkt         |  18 +++
 .../tcp_accecn_sack_space_grab.pkt            |  28 +++++
 .../tcp_accecn_sack_space_grab_with_ts.pkt    |  39 +++++++
 ...tcp_accecn_serverside_accecn_disabled1.pkt |  20 ++++
 ...tcp_accecn_serverside_accecn_disabled2.pkt |  20 ++++
 .../tcp_accecn_serverside_broken.pkt          |  19 ++++
 .../tcp_accecn_serverside_ecn_disabled.pkt    |  19 ++++
 .../tcp_accecn_serverside_only.pkt            |  18 +++
 ...n_syn_ace_flags_acked_after_retransmit.pkt |  18 +++
 .../tcp_accecn_syn_ace_flags_drop.pkt         |  16 +++
 ...n_ack_ace_flags_acked_after_retransmit.pkt |  27 +++++
 .../tcp_accecn_syn_ack_ace_flags_drop.pkt     |  26 +++++
 .../net/packetdrill/tcp_accecn_syn_ce.pkt     |  13 +++
 .../net/packetdrill/tcp_accecn_syn_ect0.pkt   |  13 +++
 .../net/packetdrill/tcp_accecn_syn_ect1.pkt   |  13 +++
 .../net/packetdrill/tcp_accecn_synack_ce.pkt  |  27 +++++
 ..._accecn_synack_ce_updates_delivered_ce.pkt |  22 ++++
 .../packetdrill/tcp_accecn_synack_ect0.pkt    |  24 ++++
 .../packetdrill/tcp_accecn_synack_ect1.pkt    |  24 ++++
 .../packetdrill/tcp_accecn_synack_rexmit.pkt  |  15 +++
 .../packetdrill/tcp_accecn_synack_rxmt.pkt    |  25 +++++
 .../packetdrill/tcp_accecn_tsnoprogress.pkt   |  26 +++++
 .../net/packetdrill/tcp_accecn_tsprogress.pkt |  25 +++++
 76 files changed, 1680 insertions(+), 102 deletions(-)
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_2nd_data_as_first.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_2nd_data_as_first_connect.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_3rd_ack_after_synack_rxmt.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_3rd_ack_ce_updates_received_ce.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_3rd_ack_lost_data_ce.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_3rd_dups.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_acc_ecn_disabled.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_accecn_then_notecn_syn.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_accecn_to_rfc3168.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_client_accecn_options_drop.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_client_accecn_options_lost.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_clientside_disabled.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_close_local_close_then_remote_fin.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_delivered_2ndlargeack.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_delivered_falseoverflow_detect.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_delivered_largeack.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_delivered_largeack2.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_delivered_maxack.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_delivered_updates.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_ecn3.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_ecn_field_updates_opt.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_ipflags_drop.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_listen_opt_drop.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_multiple_syn_ack_drop.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_multiple_syn_drop.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_negotiation_bleach.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_negotiation_connect.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_negotiation_listen.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_negotiation_noopt_connect.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_negotiation_optenable.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_no_ecn_after_accecn.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_noopt.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_noprogress.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_notecn_then_accecn_syn.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_rfc3168_to_fallback.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_rfc3168_to_rfc3168.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_sack_space_grab.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_sack_space_grab_with_ts.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_serverside_accecn_disabled1.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_serverside_accecn_disabled2.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_serverside_broken.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_serverside_ecn_disabled.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_serverside_only.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_syn_ace_flags_acked_after_retransmit.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_syn_ace_flags_drop.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_syn_ack_ace_flags_acked_after_retransmit.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_syn_ack_ace_flags_drop.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_syn_ce.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_syn_ect0.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_syn_ect1.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_synack_ce.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_synack_ce_updates_delivered_ce.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_synack_ect0.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_synack_ect1.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_synack_rexmit.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_synack_rxmt.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_tsnoprogress.pkt
 create mode 100644 tools/testing/selftests/net/packetdrill/tcp_accecn_tsprogress.pkt
====================

Link: https://patch.msgid.link/20260131222515.8485-1-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 367b491ddf97..f72eef31fa23 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -291,7 +291,8 @@ struct tcp_sock {
 	u8	nonagle     : 4,/* Disable Nagle algorithm?             */
 		rate_app_limited:1;  /* rate_{delivered,interval_us} limited? */
 	u8	received_ce_pending:4, /* Not yet transmit cnt of received_ce */
-		unused2:4;
+		accecn_opt_sent_w_dsack:1,/* Sent ACCECN opt in previous ACK w/ D-SACK */
+		unused2:3;
 	u8	accecn_minlen:2,/* Minimum length of AccECN option sent */
 		est_ecnfield:2,/* ECN field for AccECN delivered estimates */
 		accecn_opt_demand:2,/* Demand AccECN option for n next ACKs */
@@ -342,6 +343,7 @@ struct tcp_sock {
 	u32	rate_interval_us;  /* saved rate sample: time elapsed */
 	u32	rcv_rtt_last_tsecr;
 	u32	delivered_ecn_bytes[3];
+	u16	pkts_acked_ewma;/* Pkts acked EWMA for AccECN cep heuristic */
 	u64	first_tx_mstamp;  /* start of window send phase */
 	u64	delivered_mstamp; /* time we reached "delivered" */
 	u64	bytes_acked;	/* RFC4898 tcpEStatsAppHCThruOctetsAcked