tcp: apply Kern's check on RTTs used for congestion control

[karo-tx-linux.git] / net / ipv4 / tcp_input.c

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 944eaca6911596676af66a934a17685c27fc11cc..62ee71efd1ce2e65128ba5d929f70f144c1c1d02 100644 (file)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2925,9 +2925,6 @@ static inline bool tcp_ack_update_rtt(struct sock *sk, const int flag,
         * Karn's algorithm forbids taking RTT if some retransmitted data
         * is acked (RFC6298).
         */
-       if (flag & FLAG_RETRANS_DATA_ACKED)
-               seq_rtt_us = -1L;
-
        if (seq_rtt_us < 0)
                seq_rtt_us = sack_rtt_us;
 
@@ -3169,7 +3166,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
                flag |= FLAG_SACK_RENEGING;
 
        skb_mstamp_get(&now);
-       if (likely(first_ackt.v64)) {
+       if (likely(first_ackt.v64) && !(flag & FLAG_RETRANS_DATA_ACKED)) {
                seq_rtt_us = skb_mstamp_us_delta(&now, &first_ackt);
                ca_rtt_us = skb_mstamp_us_delta(&now, &last_ackt);
        }