Re: [patch v4 00/13] branch tracing support for Atom

Jan Kratochvil
2012-11-27T18:31:08Z

On Tue, 27 Nov 2012 18:30:03 +0100, Metzger, Markus T wrote:
> Btrace uses a ring buffer into which the h/w writes from-to records for each
> branch. We will only see the tail of the execution trace.

OK, I see only 168 entries here. Originally I expected kernel traps and
records the buffer each time. arch/x86/ even sets bts_interrupt_threshold,
why is the recorded buffer so short?

With such short recorded buffer I understand the backtracing feature is not
much useful. Although I do not understand why only so few entries got
recorded.

Thanks,
Jan