Re: [RFC][PATCH 2/4] tracing: add rb_event_discard() hack

From: Tom Zanussi
Date: Wed Mar 18 2009 - 02:12:20 EST



On Tue, 2009-03-17 at 21:21 -0400, Steven Rostedt wrote:
> On Tue, 17 Mar 2009, Tom Zanussi wrote:

> >
> > rb_update_read_stamp(cpu_buffer, event);
> > @@ -2026,8 +2051,8 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
> > * can have. Nesting 10 deep of interrupts is clearly
> > * an anomaly.
> > */
> > - if (RB_WARN_ON(cpu_buffer, ++nr_loops > 10))
> > - return NULL;
> > +// if (RB_WARN_ON(cpu_buffer, ++nr_loops > 10))
> > +// return NULL;
>
> Were you hitting this? If so, we need to investigate.
>

I was hitting this, but only because my code would always loop around to
'again' for a discarded event. So, 10 discarded events in a row would
trigger it.

I noticed that your fix returns instead, so it's no longer a problem.

Thanks,

Tom



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