From 3e6f049e0c4cf0606207c1a210abf50b436e9adf Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ilpo=20J=E4rvinen?= Date: Wed, 5 Dec 2007 02:20:21 -0800 Subject: [PATCH] [TCP] FRTO: Use of existing funcs make code more obvious & robust MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Though there's little need for everything that tcp_may_send_now does (actually, even the state had to be adjusted to pass some checks FRTO does not want to occur), it's more robust to let it make the decision if sending is allowed. State adjustments needed: - Make sure snd_cwnd limit is not hit in there - Disable nagle (if necessary) through the frto_counter == 2 The result of check for frto_counter in argument to call for tcp_enter_frto_loss can just be open coded, therefore there isn't need to store the previous frto_counter past tcp_may_send_now. In addition, returns can then be combined. Signed-off-by: Ilpo Järvinen Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 0f0c1c9829a1..094f8fafaf53 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3003,17 +3003,13 @@ static int tcp_process_frto(struct sock *sk, int flag) } if (tp->frto_counter == 1) { - /* Sending of the next skb must be allowed or no F-RTO */ - if (!tcp_send_head(sk) || - after(TCP_SKB_CB(tcp_send_head(sk))->end_seq, - tp->snd_una + tp->snd_wnd)) { - tcp_enter_frto_loss(sk, (tp->frto_counter == 1 ? 2 : 3), - flag); - return 1; - } - + /* tcp_may_send_now needs to see updated state */ tp->snd_cwnd = tcp_packets_in_flight(tp) + 2; tp->frto_counter = 2; + + if (!tcp_may_send_now(sk)) + tcp_enter_frto_loss(sk, 2, flag); + return 1; } else { switch (sysctl_tcp_frto_response) { -- 2.20.1