Re: [PATCH v5 net-next] net/tcp: trace all TCP/IP state transition with tcp_set_state tracepoint

2017-12-09 0:28 GMT+08:00 David Miller [off-list ref]:

From: Yafang Shao <redacted>
Date: Fri, 8 Dec 2017 23:50:44 +0800

quoted

2017-12-08 23:42 GMT+08:00 David Miller [off-list ref]:

quoted

From: Yafang Shao <redacted>
Date: Fri, 8 Dec 2017 11:40:23 +0800

quoted

It will looks like these,

    if (sk->sk_protocol == IPPROTO_TCP)
        __tcp_set_state(newsk, TCP_SYN_RECV);
    else
        newsk->sk_state = TCP_SYN_RECV;


    if (sk->sk_protocol == IPPROTO_TCP)
          __tcp_set_state(sk, TCP_CLOSE);
    else
          sk->sk_state = TCP_CLOSE;

    if (sk->sk_protocol == IPPROTO_TCP)
          tcp_state_store(sk,  state);
    else
          sk_state_store(sk, state);


Some redundant code.

IMO, put these similar code into a wrapper is more nice.

I think this discussion and how ugly this is getting shows that
tracing the state transitions of a socket is perhaps not best as a TCP
specific feature.

Do you mean that tcp_set_state tracepoint should be replaced with
sk_set_state tracepoint and move that tracepoint to
trace/events/sock.h ?

Yes, something like that.

It will avoid all of these protocol specific checks and weird
dependencies.

That looks like a good idea.
I will try to reimplemnet it.


Thanks
Yafang