[TCP]: tcp_rcv_rtt_measure_ts() call in pure-ACK path is superfluous

We only want to take receive RTT mesaurements for data
bearing frames, here in the header prediction fast path
for a pure-sender, we know that we have a pure-ACK and
thus the checks in tcp_rcv_rtt_mesaure_ts() will not pass.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index c6d62f0a9966a4ca5977161916bc310fd7b7e2c7..6d167889a4b06991becca0a99d0e4d6550bb9be0 100644 (file)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3931,8 +3931,6 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
                                    tp->rcv_nxt == tp->rcv_wup)
                                        tcp_store_ts_recent(tp);
 
-                               tcp_rcv_rtt_measure_ts(sk, skb);
-
                                /* We know that such packets are checksummed
                                 * on entry.
                                 */