From 375fe02c91792917aa26d68a87ab110d1937f44e Mon Sep 17 00:00:00 2001 From: Yuchung Cheng Date: Mon, 22 Jul 2013 16:20:45 -0700 Subject: tcp: consolidate SYNACK RTT sampling The first patch consolidates SYNACK and other RTT measurement to use a central function tcp_ack_update_rtt(). A (small) bonus is now SYNACK RTT measurement happens after PAWS check, potentially reducing the impact of RTO seeding on bad TCP timestamps values. Signed-off-by: Yuchung Cheng Signed-off-by: David S. Miller --- net/ipv4/tcp_minisocks.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'net/ipv4/tcp_minisocks.c') diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index ab1c086..58a3e69 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -411,6 +411,8 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, newtp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tcp_enable_early_retrans(newtp); newtp->tlp_high_seq = 0; + newtp->lsndtime = treq->snt_synack; + newtp->total_retrans = req->num_retrans; /* So many TCP implementations out there (incorrectly) count the * initial SYN frame in their delayed-ACK and congestion control @@ -666,12 +668,6 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, if (!(flg & TCP_FLAG_ACK)) return NULL; - /* Got ACK for our SYNACK, so update baseline for SYNACK RTT sample. */ - if (tmp_opt.saw_tstamp && tmp_opt.rcv_tsecr) - tcp_rsk(req)->snt_synack = tmp_opt.rcv_tsecr; - else if (req->num_retrans) /* don't take RTT sample if retrans && ~TS */ - tcp_rsk(req)->snt_synack = 0; - /* For Fast Open no more processing is needed (sk is the * child socket). */ -- cgit v1.1