Re: [PATCH] tracing: add trace console

Steven Rostedt
2011-11-16T16:41:37Z

On Wed, 2011-11-16 at 16:17 +0100, Johannes Berg wrote:
> On Wed, 2011-11-16 at 10:10 -0500, Christoph Hellwig wrote:
> > On Wed, Nov 16, 2011 at 11:18:48AM +0100, Johannes Berg wrote:
> > > From: Johannes Berg <johannes.berg@intel.com>
> > >
> > > As described in the Kconfig entry, logging printk
> > > output is useful to correlate (existing) printk
> > > debugging with (existing) tracing. The easiest way
> > > to achieve this is to register a console that just
> > > calls trace_printk(), which this module does.
> >
> > I'd much prefer if we could have it built in all the time, but had a
> > way to enable it at runtime, just like all the "real" tracepoints.
>
> That's possible, basically adding a tracepoints to printk -- that would
> even catch everything and not require setting the console level (which
> has its advantages too since other consoles might be slow).
>
> It's a completely different thing though. I did it this way because it
> was trivial to do out of tree for a quick test I was doing yesterday.
> Doing it the other way is obviously more intrusive in core code.

I'm not sure it would be too invasive. Think you could get something
working?

-- Steve