Re: tracing ring_buffer_resize oops.

From: Dave Jones
Date: Thu May 24 2012 - 18:57:08 EST


On Thu, May 24, 2012 at 06:49:41PM -0400, Steven Rostedt wrote:
> On Thu, 2012-05-24 at 16:05 -0400, Dave Jones wrote:
> > On Thu, May 24, 2012 at 03:24:55PM -0400, Steven Rostedt wrote:
> > > On Thu, 2012-05-24 at 15:11 -0400, Dave Jones wrote:
> > >
> > > > > Also, how reproducible is it? When it triggered for me, it was constant.
> > > > > Every boot and test failed. But after I did the make mrproper, I have
> > > > > not been able to trigger it again. This is why I put it down as a bad
> > > > > build.
> > > >
> > > > happens every time for me so far.
> > >
> > > Did you also do a make mrproper and try again?
> >
> > ok, that's nasty. Works fine after a make clean.
> >
>
> Hmm, I did two make mrproper builds and they both failed. So this isn't
> a build issue. Must just be some nasty race. I'm still leaning that this
> has to do with the breakpoint function tracing updates.
>
> Looking deeper into it.
>
> -- Steve

Possibly unrelated, but I found that it only worked once per boot. Is that expected ?

echo irqsoff > current_tracer
echo latency-format > trace_options
echo 0 > tracing_max_latency
echo 1 > tracing_on
blah
echo 0 > tracing_on
cat trace

showed me a trace as I expected

repeating the same commands then got me an empty trace.

what gives ?

Dave

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