Re: [PATCH net-next v4 4/4] net: tcp: refactor the dbg message in tcp_retransmit_timer()

From: Eric Dumazet
Date: Fri Aug 11 2023 - 03:39:02 EST


On Fri, Aug 11, 2023 at 5:01 AM <menglong8.dong@xxxxxxxxx> wrote:
>
> From: Menglong Dong <imagedong@xxxxxxxxxxx>
>
> The debug message in tcp_retransmit_timer() is slightly wrong, because
> they could be printed even if we did not receive a new ACK packet from
> the remote peer.
>
> Change it to probing zero-window, as it is a expected case now. The
> description may be not correct.
>
> Adding the duration since the last ACK we received, and the duration of
> the retransmission, which are useful for debugging.
>
> And the message now like this:
>
> Probing zero-window on 127.0.0.1:9999/46946, seq=3737778959:3737791503, recv 209ms ago, lasting 209ms
> Probing zero-window on 127.0.0.1:9999/46946, seq=3737778959:3737791503, recv 404ms ago, lasting 408ms
> Probing zero-window on 127.0.0.1:9999/46946, seq=3737778959:3737791503, recv 812ms ago, lasting 1224ms

Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>