From 98fa6271cfcb1de873b3fe0caf48d9daa1bcc0ac Mon Sep 17 00:00:00 2001 From: Yuchung Cheng Date: Mon, 29 Apr 2019 15:46:20 -0700 Subject: [PATCH] tcp: refactor setting the initial congestion window Relocate the congestion window initialization from tcp_init_metrics() to tcp_init_transfer() to improve code readability. Signed-off-by: Yuchung Cheng Signed-off-by: Neal Cardwell Signed-off-by: Soheil Hassas Yeganeh Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 12 ------------ net/ipv4/tcp_input.c | 26 ++++++++++++++++++++++++++ net/ipv4/tcp_metrics.c | 10 ---------- 3 files changed, 26 insertions(+), 22 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index f7567a3698eb..1fa15beb8380 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -457,18 +457,6 @@ void tcp_init_sock(struct sock *sk) } EXPORT_SYMBOL(tcp_init_sock); -void tcp_init_transfer(struct sock *sk, int bpf_op) -{ - struct inet_connection_sock *icsk = inet_csk(sk); - - tcp_mtup_init(sk); - icsk->icsk_af_ops->rebuild_header(sk); - tcp_init_metrics(sk); - tcp_call_bpf(sk, bpf_op, 0, NULL); - tcp_init_congestion_control(sk); - tcp_init_buffer_space(sk); -} - static void tcp_tx_timestamp(struct sock *sk, u16 tsflags) { struct sk_buff *skb = tcp_write_queue_tail(sk); diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 706a99ec73f6..077d9abdfcf5 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5647,6 +5647,32 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb) } EXPORT_SYMBOL(tcp_rcv_established); +void tcp_init_transfer(struct sock *sk, int bpf_op) +{ + struct inet_connection_sock *icsk = inet_csk(sk); + struct tcp_sock *tp = tcp_sk(sk); + + tcp_mtup_init(sk); + icsk->icsk_af_ops->rebuild_header(sk); + tcp_init_metrics(sk); + + /* Initialize the congestion window to start the transfer. + * Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been + * retransmitted. In light of RFC6298 more aggressive 1sec + * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK + * retransmission has occurred. + */ + if (tp->total_retrans > 1 && tp->undo_marker) + tp->snd_cwnd = 1; + else + tp->snd_cwnd = tcp_init_cwnd(tp, __sk_dst_get(sk)); + tp->snd_cwnd_stamp = tcp_jiffies32; + + tcp_call_bpf(sk, bpf_op, 0, NULL); + tcp_init_congestion_control(sk); + tcp_init_buffer_space(sk); +} + void tcp_finish_connect(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c index d4d687330e2b..c4848e7a0aad 100644 --- a/net/ipv4/tcp_metrics.c +++ b/net/ipv4/tcp_metrics.c @@ -512,16 +512,6 @@ void tcp_init_metrics(struct sock *sk) inet_csk(sk)->icsk_rto = TCP_TIMEOUT_FALLBACK; } - /* Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been - * retransmitted. In light of RFC6298 more aggressive 1sec - * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK - * retransmission has occurred. - */ - if (tp->total_retrans > 1 && tp->undo_marker) - tp->snd_cwnd = 1; - else - tp->snd_cwnd = tcp_init_cwnd(tp, dst); - tp->snd_cwnd_stamp = tcp_jiffies32; } bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst)