diff options
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 8fc97f4d8a6b..ff19f6e54d55 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -928,9 +928,15 @@ void tcp_rcv_space_adjust(struct sock *sk) trace_tcp_rcv_space_adjust(sk); - tcp_mstamp_refresh(tp); + if (unlikely(!tp->rcv_rtt_est.rtt_us)) + return; + + /* We do not refresh tp->tcp_mstamp here. + * Some platforms have expensive ktime_get() implementations. + * Using the last cached value is enough for DRS. + */ time = tcp_stamp_us_delta(tp->tcp_mstamp, tp->rcvq_space.time); - if (time < (tp->rcv_rtt_est.rtt_us >> 3) || tp->rcv_rtt_est.rtt_us == 0) + if (time < (tp->rcv_rtt_est.rtt_us >> 3)) return; /* Number of bytes copied to user in last RTT */ |