On Mon, Jan 9, 2023 at 11:39 PM Steven Rostedt [off-list ref] wrote:

But looking at this tracepoint again, I see a issue that can help with the
dereferencing.

Why is family and protocol passed in?

+       trace_sock_send_length(sock->sk, sock->sk->sk_family,
+                              sock->sk->sk_protocol, ret, 0);


Where the TP_fast_assign() is:

+       TP_fast_assign(
+               __entry->sk = sk;
+               __entry->family = sk->sk_family;
+               __entry->protocol = sk->sk_protocol;
+               __entry->length = ret > 0 ? ret : 0;
+               __entry->error = ret < 0 ? ret : 0;
+               __entry->flags = flags;
+       ),

The family and protocol is taken from the sk, and not the parameters. I bet
dropping those would help.

-- Steve

Many thanks to Eric and Steven for your discussions and suggestions, I
will update on v5.


Thanks,
Yunhui