From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH net-next] tcp: handle EOR and FIN conditions the same in tcp_tso_should_defer() Date: Mon, 10 Dec 2018 06:10:02 -0800 Message-ID: <20181210141002.108196-1-edumazet@google.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Cc: netdev , Eric Dumazet , Neal Cardwell , Soheil Hassas Yeganeh , Yuchung Cheng , Eric Dumazet To: "David S . Miller" Return-path: Received: from mail-pf1-f196.google.com ([209.85.210.196]:35107 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727197AbeLJOKH (ORCPT ); Mon, 10 Dec 2018 09:10:07 -0500 Received: by mail-pf1-f196.google.com with SMTP id z9so5464687pfi.2 for ; Mon, 10 Dec 2018 06:10:07 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: In commit f9bfe4e6a9d0 ("tcp: lack of available data can also cause TSO defer") we moved the test in tcp_tso_should_defer() for packets with a FIN flag, and we mentioned that the same would be done later for EOR flag. Both flags should be handled at the same time, after all other heuristics have been considered. They both mean that no more bytes can be added to this skb by an application. Signed-off-by: Eric Dumazet --- net/ipv4/tcp_output.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index c31badfee806a70d5af6dc033cf9155adb1f9375..730bc44dbad9363814705b28c2f91a2253d91207 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1947,10 +1947,6 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb, if ((skb != tcp_write_queue_tail(sk)) && (limit >= skb->len)) goto send_now; - /* If this packet won't get more data, do not wait. */ - if (TCP_SKB_CB(skb)->eor) - goto send_now; - win_divisor = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_tso_win_divisor); if (win_divisor) { u32 chunk = min(tp->snd_wnd, tp->snd_cwnd * tp->mss_cache); @@ -1999,7 +1995,8 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb, } /* If this packet won't get more data, do not wait. */ - if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) + if ((TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) || + TCP_SKB_CB(skb)->eor) goto send_now; return true; -- 2.20.0.rc2.403.gdbc3b29805-goog