Re: [PATCH v2 net-next] tcp: use data length instead of skb->len in tcp_probe

[Song Liu]

> On May 25, 2018, at 3:14 AM, Yafang Shao <laoar.shao@xxxxxxxxx> wrote:
> 
> skb->len is meaningless to user.
> data length could be more helpful, with which we can easily filter out
> the packet without payload.
> 
> Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>

Acked-by: Song Liu <songliubraving@xxxxxx>


> ---
> include/trace/events/tcp.h | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h
> index c1a5284..703abb6 100644
> --- a/include/trace/events/tcp.h
> +++ b/include/trace/events/tcp.h
> @@ -236,7 +236,7 @@
> 		__field(__u16, sport)
> 		__field(__u16, dport)
> 		__field(__u32, mark)
> -		__field(__u16, length)
> +		__field(__u16, data_len)
> 		__field(__u32, snd_nxt)
> 		__field(__u32, snd_una)
> 		__field(__u32, snd_cwnd)
> @@ -261,7 +261,7 @@
> 		__entry->dport = ntohs(inet->inet_dport);
> 		__entry->mark = skb->mark;
> 
> -		__entry->length = skb->len;
> +		__entry->data_len = skb->len - tcp_hdrlen(skb);
> 		__entry->snd_nxt = tp->snd_nxt;
> 		__entry->snd_una = tp->snd_una;
> 		__entry->snd_cwnd = tp->snd_cwnd;
> @@ -272,9 +272,9 @@
> 		__entry->sock_cookie = sock_gen_cookie(sk);
> 	),
> 
> -	TP_printk("src=%pISpc dest=%pISpc mark=%#x length=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx",
> +	TP_printk("src=%pISpc dest=%pISpc mark=%#x data_len=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx",
> 		  __entry->saddr, __entry->daddr, __entry->mark,
> -		  __entry->length, __entry->snd_nxt, __entry->snd_una,
> +		  __entry->data_len, __entry->snd_nxt, __entry->snd_una,
> 		  __entry->snd_cwnd, __entry->ssthresh, __entry->snd_wnd,
> 		  __entry->srtt, __entry->rcv_wnd, __entry->sock_cookie)
> );
> -- 
> 1.8.3.1
>