summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorNeal Cardwell <ncardwell@google.com>2013-03-04 10:23:05 +0400
committerDavid S. Miller <davem@davemloft.net>2013-03-04 23:12:07 +0400
commitaab2b4bf224ef8358d262f95b568b8ad0cecf0a0 (patch)
treee16e5214f01f53975cb214dc98d153c9c96fe7db /net
parentd2123be0e55101742dacd6dae60cdd0f1e2ef302 (diff)
downloadlinux-aab2b4bf224ef8358d262f95b568b8ad0cecf0a0.tar.xz
tcp: fix double-counted receiver RTT when leaving receiver fast path
We should not update ts_recent and call tcp_rcv_rtt_measure_ts() both before and after going to step5. That wastes CPU and double-counts the receiver-side RTT sample. Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/ipv4/tcp_input.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index a759e19496d2..0d9bdacce99f 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5485,6 +5485,9 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
if (tcp_checksum_complete_user(sk, skb))
goto csum_error;
+ if ((int)skb->truesize > sk->sk_forward_alloc)
+ goto step5;
+
/* Predicted packet is in window by definition.
* seq == rcv_nxt and rcv_wup <= rcv_nxt.
* Hence, check seq<=rcv_wup reduces to:
@@ -5496,9 +5499,6 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
tcp_rcv_rtt_measure_ts(sk, skb);
- if ((int)skb->truesize > sk->sk_forward_alloc)
- goto step5;
-
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPHPHITS);
/* Bulk data transfer: receiver */