From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yuchung Cheng Subject: [PATCH net-next 5/8] tcp: new helper tcp_timeout_mark_lost Date: Wed, 16 May 2018 16:40:14 -0700 Message-ID: <20180516234017.172775-6-ycheng@google.com> References: <20180516234017.172775-1-ycheng@google.com> Cc: netdev@vger.kernel.org, edumazet@google.com, ncardwell@google.com, soheil@google.com, priyarjha@google.com, Yuchung Cheng To: davem@davemloft.net Return-path: Received: from mail-wm0-f65.google.com ([74.125.82.65]:37554 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751984AbeEPXkt (ORCPT ); Wed, 16 May 2018 19:40:49 -0400 Received: by mail-wm0-f65.google.com with SMTP id l1-v6so5771493wmb.2 for ; Wed, 16 May 2018 16:40:48 -0700 (PDT) In-Reply-To: <20180516234017.172775-1-ycheng@google.com> Sender: netdev-owner@vger.kernel.org List-ID: Refactor using a new helper, tcp_timeout_mark_loss(), that marks packets lost upon RTO. Signed-off-by: Yuchung Cheng Signed-off-by: Neal Cardwell Reviewed-by: Eric Dumazet Reviewed-by: Soheil Hassas Yeganeh Reviewed-by: Priyaranjan Jha --- net/ipv4/tcp_input.c | 50 +++++++++++++++++++++++++------------------- 1 file changed, 29 insertions(+), 21 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 6fb0a28977a0..af32accda2a9 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1917,18 +1917,43 @@ static inline void tcp_init_undo(struct tcp_sock *tp) tp->undo_retrans = tp->retrans_out ? : -1; } -/* Enter Loss state. If we detect SACK reneging, forget all SACK information +/* If we detect SACK reneging, forget all SACK information * and reset tags completely, otherwise preserve SACKs. If receiver * dropped its ofo queue, we will know this due to reneging detection. */ +static void tcp_timeout_mark_lost(struct sock *sk) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct sk_buff *skb; + bool is_reneg; /* is receiver reneging on SACKs? */ + + skb = tcp_rtx_queue_head(sk); + is_reneg = skb && (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED); + if (is_reneg) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSACKRENEGING); + tp->sacked_out = 0; + /* Mark SACK reneging until we recover from this loss event. */ + tp->is_sack_reneg = 1; + } else if (tcp_is_reno(tp)) { + tcp_reset_reno_sack(tp); + } + + skb_rbtree_walk_from(skb) { + if (is_reneg) + TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_ACKED; + tcp_mark_skb_lost(sk, skb); + } + tcp_verify_left_out(tp); + tcp_clear_all_retrans_hints(tp); +} + +/* Enter Loss state. */ void tcp_enter_loss(struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); - struct sk_buff *skb; bool new_recovery = icsk->icsk_ca_state < TCP_CA_Recovery; - bool is_reneg; /* is receiver reneging on SACKs? */ /* Reduce ssthresh if it has not yet been made inside this window. */ if (icsk->icsk_ca_state <= TCP_CA_Disorder || @@ -1944,24 +1969,7 @@ void tcp_enter_loss(struct sock *sk) tp->snd_cwnd_cnt = 0; tp->snd_cwnd_stamp = tcp_jiffies32; - if (tcp_is_reno(tp)) - tcp_reset_reno_sack(tp); - - skb = tcp_rtx_queue_head(sk); - is_reneg = skb && (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED); - if (is_reneg) { - NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSACKRENEGING); - tp->sacked_out = 0; - /* Mark SACK reneging until we recover from this loss event. */ - tp->is_sack_reneg = 1; - } - skb_rbtree_walk_from(skb) { - if (is_reneg) - TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_ACKED; - tcp_mark_skb_lost(sk, skb); - } - tcp_verify_left_out(tp); - tcp_clear_all_retrans_hints(tp); + tcp_timeout_mark_lost(sk); /* Timeout in disordered state after receiving substantial DUPACKs * suggests that the degree of reordering is over-estimated. -- 2.17.0.441.gb46fe60e1d-goog