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Date:   Wed, 26 Apr 2023 15:47:13 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Vladimir Oltean <vladimir.oltean@nxp.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Masami Hiramatsu <mhiramat@kernel.org>, netdev@vger.kernel.org,
        Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>
Subject: Re: [PATCH net-next 0/2] DSA trace events
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On Wed, 26 Apr 2023 22:43:01 +0300
Vladimir Oltean <vladimir.oltean@nxp.com> wrote:

> Instead of living in fear that this might happen, I think what would be
> the most productive thing to do would be to just create a proper API in
> the next kernel development cycle to expose just that information, and
> point other people to that other API, and keep the trace events just for
> debugging.

I also want to add that if a tool does use a trace event that was not your
intention, you can then fix the tool to do it properly.

I had this with powertop. It had hardcoded events (did not use
libtraceevent) and when I modified the layout, it broke, and Linus reverted
my changes. After fixing powertop to do things properly, I was able to get
my changes back in.

So even if you do break user space, you can still fix it later.

-- Steve