On Tue, 2014-08-12 at 13:45 +0400, Andrey Vagin wrote:
> We don't know right timestamp for repaired skb-s. Wrong RTT estimations
> isn't good, because some congestion modules heavily depends on it.
>
> This patch adds the TCPCB_REPAIRED flag, which is included in
> TCPCB_RETRANS.
...
> +
> + /* All packets are restored as if they have
> + * already been sent. skb_mstamp isn't set to
> + * avoid wrong rtt estimation.
> + */
> + if (tp->repair) {
> + TCP_SKB_CB(skb)->sacked |=
> TCPCB_REPAIRED;
> + TCP_SKB_CB(skb)->when = tcp_time_stamp;
> + }
> }
>
> /* Try to append data to the end of skb. */
Are you sure TCP_SKB_CB(skb)->when needs to be set ?
It should not anymore.
If yes, I believe a comment would help a lot here.
Also, please include this tag to ease stable backports (3.15+) :
Fixes: 431a91242d8d ("tcp: timestamp SYN+DATA messages")
Fixes: 740b0f1841f6 ("tcp: switch rtt estimations to usec resolution")
Thanks !
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
