From: Chia-Yu Chang chia-yu.chang@nokia-bell-labs.com
Before this patch, retransmitted SYN/ACK did not have a specific synack_type; however, the upcoming patch needs to distinguish between retransmitted and non-retransmitted SYN/ACK for AccECN negotiation to transmit the fallback SYN/ACK during AccECN negotiation. Therefore, this patch introduces a new synack_type (TCP_SYNACK_RETRANS).
Signed-off-by: Chia-Yu Chang chia-yu.chang@nokia-bell-labs.com
--- v6: - Add new synack_type instead of moving the increment of num_retran. --- include/net/tcp.h | 1 + net/ipv4/tcp_output.c | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/include/net/tcp.h b/include/net/tcp.h index a8eb67ff1568..510d2e595b08 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -541,6 +541,7 @@ enum tcp_synack_type { TCP_SYNACK_NORMAL, TCP_SYNACK_FASTOPEN, TCP_SYNACK_COOKIE, + TCP_SYNACK_RETRANS, }; struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, struct request_sock *req, diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 8039c726d235..5fa14a73d03f 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -3921,6 +3921,7 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst,
switch (synack_type) { case TCP_SYNACK_NORMAL: + case TCP_SYNACK_RETRANS: skb_set_owner_edemux(skb, req_to_sk(req)); break; case TCP_SYNACK_COOKIE: @@ -4606,7 +4607,7 @@ int tcp_rtx_synack(const struct sock *sk, struct request_sock *req) /* Paired with WRITE_ONCE() in sock_setsockopt() */ if (READ_ONCE(sk->sk_txrehash) == SOCK_TXREHASH_ENABLED) WRITE_ONCE(tcp_rsk(req)->txhash, net_tx_rndhash()); - res = af_ops->send_synack(sk, NULL, &fl, req, NULL, TCP_SYNACK_NORMAL, + res = af_ops->send_synack(sk, NULL, &fl, req, NULL, TCP_SYNACK_RETRANS, NULL); if (!res) { TCP_INC_STATS(sock_net(sk), TCP_MIB_RETRANSSEGS);