diff options
| author | Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com> | 2026-01-31 23:25:05 +0100 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2026-02-03 15:13:24 +0100 |
| commit | e68c28f22f46ecfdec3656ae785dd8ccbb4d557d (patch) | |
| tree | f4c397209b220407d95df5ee4e1caa3538018ffb /net | |
| parent | 100f946b8d44b64bc0b8a8c30d283105031c0a77 (diff) | |
tcp: disable RFC3168 fallback identifier for CC modules
When AccECN is not successfully negociated for a TCP flow, it defaults
fallback to classic ECN (RFC3168). However, L4S service will fallback
to non-ECN.
This patch enables congestion control module to control whether it
should not fallback to classic ECN after unsuccessful AccECN negotiation.
A new CA module flag (TCP_CONG_NO_FALLBACK_RFC3168) identifies this
behavior expected by the CA.
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-6-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp_input.c | 2 | ||||
| -rw-r--r-- | net/ipv4/tcp_minisocks.c | 7 |
2 files changed, 5 insertions, 4 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index e823a3b1ad3b..59dafcb45c16 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -7090,7 +7090,7 @@ consume: tp->snd_wl1 = TCP_SKB_CB(skb)->seq; tp->max_window = tp->snd_wnd; - tcp_ecn_rcv_syn(tp, th, skb); + tcp_ecn_rcv_syn(sk, th, skb); tcp_mtup_init(sk); tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index bd5462154f97..9776c921d1bb 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -485,9 +485,10 @@ static void tcp_ecn_openreq_child(struct sock *sk, tp->accecn_opt_demand = 1; tcp_ecn_received_counters_payload(sk, skb); } else { - tcp_ecn_mode_set(tp, inet_rsk(req)->ecn_ok ? - TCP_ECN_MODE_RFC3168 : - TCP_ECN_DISABLED); + if (inet_rsk(req)->ecn_ok && !tcp_ca_no_fallback_rfc3168(sk)) + tcp_ecn_mode_set(tp, TCP_ECN_MODE_RFC3168); + else + tcp_ecn_mode_set(tp, TCP_ECN_DISABLED); } } |