From: Martin KaFai Lau <[email protected]>
Date: Thu, 10 Mar 2016 10:46:22 -0800
> Per RFC4898, they count segments sent/received
> containing a positive length data segment (that includes
> retransmission segments carrying data). Unlike
> tcpi_segs_out/in, tcpi_data_segs_out/in excludes segments
> carrying no data (e.g. pure ack).
>
> The patch also updates the segs_in in tcp_fastopen_add_skb()
> so that segs_in >= data_segs_in property is kept.
>
> Together with retransmission data, tcpi_data_segs_out
> gives a better signal on the rxmit rate.
>
> v5: Eric pointed out that checking skb->len is still needed in
> tcp_fastopen_add_skb() because skb can carry a FIN without data.
> Hence, instead of open coding segs_in and data_segs_in, tcp_segs_in()
> helper is used. Comment is added to the fastopen case to explain why
> segs_in has to be reset and tcp_segs_in() has to be called before
> __skb_pull().
>
> v4: Add comment to the changes in tcp_fastopen_add_skb()
> and also add remark on this case in the commit message.
>
> v3: Add const modifier to the skb parameter in tcp_segs_in()
>
> v2: Rework based on recent fix by Eric:
> commit a9d99ce28ed3 ("tcp: fix tcpi_segs_in after connection establishment")
>
> Signed-off-by: Martin KaFai Lau <[email protected]>
This doesn't apply cleanly to net-next, please respin.
Thanks.
