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Date: Sat, 6 Sep 2008 13:39:55 +0200
From: "=?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?=" <fweisbec@gmail.com>
To: "Steven Rostedt" <rostedt@goodmis.org>
Subject: Re: [Patch] Tracing/ftrace: Adds a marker to allow user comments
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2008/9/4 Steven Rostedt <rostedt@goodmis.org>:

> For logdev (my pet project from way back, and the latest ftrace is based
> on), I had a CUSTOM type. The API allowed to register a callback to a
> type, and it would associate that type to some number (descriptor) and
> pass that number back to you. Then you could use this number to write to
> the buffer using the CUSTOM type and registered number. On output, when a
> CUSTOM type is detected, it would read the custom.id (the number) and
> search for any registered callbacks to handle the entry.
>
> This probably would not be too difficult to implement. Especially since it
> is already implemented in logdev.
> (see http://rostedt.homelinux.com/logdev/)
>
> -- Steve

Why not. It is a way for a tracer to handle output for any type of entries.
But will this feature really be used for other special types than
TRACE_PRINT? I'm not sure... If it is not the case, the Pekka's
solution seems to me far more simple.

But actually I don't know the needs of others tracers...