From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH net-next 13/15] tcp_lp: cache tcp_time_stamp Date: Tue, 16 May 2017 14:00:12 -0700 Message-ID: <20170516210014.31176-14-edumazet@google.com> References: <20170516210014.31176-1-edumazet@google.com> Cc: netdev , Eric Dumazet , Eric Dumazet To: "David S . Miller" , Neal Cardwell , Yuchung Cheng , Soheil Hassas Yeganeh , Wei Wang Return-path: Received: from mail-pf0-f182.google.com ([209.85.192.182]:33017 "EHLO mail-pf0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752928AbdEPV2c (ORCPT ); Tue, 16 May 2017 17:28:32 -0400 Received: by mail-pf0-f182.google.com with SMTP id e193so86503645pfh.0 for ; Tue, 16 May 2017 14:28:32 -0700 (PDT) In-Reply-To: <20170516210014.31176-1-edumazet@google.com> Sender: netdev-owner@vger.kernel.org List-ID: tcp_time_stamp will become slightly more expensive soon, cache its value. Signed-off-by: Eric Dumazet --- net/ipv4/tcp_lp.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/ipv4/tcp_lp.c b/net/ipv4/tcp_lp.c index d6fb6c067af4641f232b94e7c590c212648e8173..ef3122abb3734a63011fba035f7a7aae431da8de 100644 --- a/net/ipv4/tcp_lp.c +++ b/net/ipv4/tcp_lp.c @@ -264,18 +264,19 @@ static void tcp_lp_pkts_acked(struct sock *sk, const struct ack_sample *sample) { struct tcp_sock *tp = tcp_sk(sk); struct lp *lp = inet_csk_ca(sk); + u32 now = tcp_time_stamp; u32 delta; if (sample->rtt_us > 0) tcp_lp_rtt_sample(sk, sample->rtt_us); /* calc inference */ - delta = tcp_time_stamp - tp->rx_opt.rcv_tsecr; + delta = now - tp->rx_opt.rcv_tsecr; if ((s32)delta > 0) lp->inference = 3 * delta; /* test if within inference */ - if (lp->last_drop && (tcp_time_stamp - lp->last_drop < lp->inference)) + if (lp->last_drop && (now - lp->last_drop < lp->inference)) lp->flag |= LP_WITHIN_INF; else lp->flag &= ~LP_WITHIN_INF; @@ -312,7 +313,7 @@ static void tcp_lp_pkts_acked(struct sock *sk, const struct ack_sample *sample) tp->snd_cwnd = max(tp->snd_cwnd >> 1U, 1U); /* record this drop time */ - lp->last_drop = tcp_time_stamp; + lp->last_drop = now; } static struct tcp_congestion_ops tcp_lp __read_mostly = { -- 2.13.0.303.g4ebf302169-goog