From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v2 net-next] tcp: add tracepoint
 trace_tcp_retransmit_synack()
Date: Fri, 03 Nov 2017 10:13:22 +0900 (KST)
Message-ID: <20171103.101322.1439534279100072262.davem@davemloft.net>
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        <20171030214135.2444870-2-songliubraving@fb.com>
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Cc: netdev@vger.kernel.org, alexei.starovoitov@gmail.com,
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From: Song Liu <songliubraving@fb.com>
Date: Mon, 30 Oct 2017 14:41:35 -0700

> This tracepoint can be used to trace synack retransmits. It maintains
> pointer to struct request_sock.
> 
> We cannot simply reuse trace_tcp_retransmit_skb() here, because the
> sk here is the LISTEN socket. The IP addresses and ports should be
> extracted from struct request_sock.
> 
> Note that, like many other tracepoints, this patch uses IS_ENABLED
> in TP_fast_assign macro, which triggers sparse warning like:
> 
> ./include/trace/events/tcp.h:274:1: error: directive in argument list
> ./include/trace/events/tcp.h:281:1: error: directive in argument list
> 
> However, there is no good solution to avoid these warnings. To the
> best of our knowledge, these warnings are harmless.
> 
> Signed-off-by: Song Liu <songliubraving@fb.com>
> Acked-by: Alexei Starovoitov <ast@kernel.org>
> Acked-by: Martin KaFai Lau <kafai@fb.com>

Applied.