[PATCH net-next v2 2/3] tcp: ECT_1_ESTABLISH identifier for CA
flat view
HOTtoday
From: <hidden>
Date: 2026-10-18 21:15:29
Also in:
bpf, linux-kselftest
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
Revision v2 of 2 in this series.
Revisions (2)
- v1 [diff vs current]
- v2 current
From: Chia-Yu Chang <redacted> When connection is initialized after ECN negotiation, this patch enables CA to control whether ECT(0) or ECT(1) should be used. A new identiifer (TCP_CONG_ECT_1_ESTABLISH) defines the expected ECT value in the IP header. Signed-off-by: Chia-Yu Chang <redacted> --- include/net/tcp.h | 1 + include/net/tcp_ecn.h | 6 ++++++ net/ipv4/tcp_cong.c | 4 +++- net/ipv4/tcp_output.c | 2 +- 4 files changed, 11 insertions(+), 2 deletions(-)
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 1838389a9d8a..b9def462479d 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h@@ -428,6 +428,7 @@ static inline void tcp_dec_quickack_mode(struct sock *sk) #define TCP_ECN_DEMAND_CWR BIT(2) #define TCP_ECN_SEEN BIT(3) #define TCP_ECN_MODE_ACCECN BIT(4) +#define TCP_ECN_ECT_1_ESTABLISH BIT(5) #define TCP_ECN_DISABLED 0 #define TCP_ECN_MODE_PENDING (TCP_ECN_MODE_RFC3168 | TCP_ECN_MODE_ACCECN)
diff --git a/include/net/tcp_ecn.h b/include/net/tcp_ecn.h
index 865d5c5a7718..210ec63538f8 100644
--- a/include/net/tcp_ecn.h
+++ b/include/net/tcp_ecn.h@@ -38,6 +38,12 @@ static inline void INET_ECN_xmit_ect_1_negotiation(struct sock *sk) __INET_ECN_xmit(sk, tcp_ca_ect_1_negotiation(sk)); } +/* Apply either ECT(0) or ECT(1) based on TCP_CONG_ECT_1_ESTABLISH flag */ +static inline void INET_ECN_xmit_ect_1_establish(struct sock *sk) +{ + __INET_ECN_xmit(sk, tcp_sk(sk)->ecn_flags & TCP_ECN_ECT_1_ESTABLISH); +} + static inline void tcp_ecn_queue_cwr(struct tcp_sock *tp) { /* Do not set CWR if in AccECN mode! */
diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c
index 8e83ef81fc18..8da2a9a34b29 100644
--- a/net/ipv4/tcp_cong.c
+++ b/net/ipv4/tcp_cong.c@@ -240,7 +240,9 @@ void tcp_init_congestion_control(struct sock *sk) tcp_sk(sk)->prior_ssthresh = 0; if (icsk->icsk_ca_ops->init) icsk->icsk_ca_ops->init(sk); - if (tcp_ca_needs_ecn(sk)) + if (tcp_ca_needs_accecn(sk)) + INET_ECN_xmit_ect_1_establish(sk); + else if (tcp_ca_needs_ecn(sk)) INET_ECN_xmit(sk); else INET_ECN_dontxmit(sk);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index c8865205cdc8..3248f3895b15 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c@@ -350,7 +350,7 @@ static void tcp_ecn_send(struct sock *sk, struct sk_buff *skb, if (tcp_ecn_mode_accecn(tp)) { if (!tcp_accecn_ace_fail_recv(tp) && !tcp_accecn_ace_fail_send(tp)) - INET_ECN_xmit(sk); + INET_ECN_xmit_ect_1_establish(sk); else INET_ECN_dontxmit(sk); tcp_accecn_set_ace(tp, skb, th);
--
2.34.1