On Wed, Dec 5, 2018 at 5:24 PM Eric Dumazet <eduma...@google.com> wrote:
>
> If available rwnd is too small, tcp_tso_should_defer()
> can decide it is worth waiting before splitting a TSO packet.
>
> This really means we are rwnd limited.
>
> Fixes: 5615f88614a4 ("tcp: instrument how long TCP is limited by receive
> window")
> Signed-off-by: Eric Dumazet <eduma...@google.com>
Acked-by: Soheil Hassas Yeganeh <soh...@google.com>
Excellent catch! Thank you for the fix, Eric!
> ---
> net/ipv4/tcp_output.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
> index
> 68b5326f73212ffe7111dd0f91e0a1246fb0ae25..3186902347584090256467d8679320666aa0257e
> 100644
> --- a/net/ipv4/tcp_output.c
> +++ b/net/ipv4/tcp_output.c
> @@ -2356,8 +2356,11 @@ static bool tcp_write_xmit(struct sock *sk, unsigned
> int mss_now, int nonagle,
> } else {
> if (!push_one &&
> tcp_tso_should_defer(sk, skb, &is_cwnd_limited,
> - max_segs))
> + max_segs)) {
> + if (!is_cwnd_limited)
> + is_rwnd_limited = true;
> break;
> + }
> }
>
> limit = mss_now;
> --
> 2.20.0.rc2.403.gdbc3b29805-goog
>
