Date: Tue, 18 Apr 2017 22:49:53 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Frank Rowand <frowand.list@gmail.com>
Cc: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>, robh+dt@kernel.org,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, nfont@linux.vnet.ibm.com,
        mpe@ellerman.id.au, mingo@redhat.com
Subject: Re: [PATCH] of: introduce event tracepoints for dynamic device_node
 lifecyle
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On Tue, 18 Apr 2017 18:42:32 -0700
Frank Rowand <frowand.list@gmail.com> wrote:

> And of course the other issue with using tracepoints is the extra space
> required to hold the tracepoint info.  With the pr_debug() approach, the
> space usage can be easily removed for a production kernel via a config
> option.

Now if you are saying you want to be able to enable debugging without
the tracing infrastructure I would agree. As the tracing infrastructure
is large. But I'm working on shrinking it more.

> 
> Tracepoints are wonderful technology, but not always the proper tool to
> use for debug info.

But if you are going to have tracing enabled regardless, adding a few
more tracepoints isn't going to make the difference.

-- Steve

> 
> > If Rob wants to convert printk() style data to trace data (and I can't
> > convince him otherwise) then I will have further comments on this specific
> > patch.
> >