Re: Shift by one instruction in the perf annotate output

From: Peter Zijlstra
Date: Fri Jan 27 2012 - 05:49:39 EST


On Fri, 2012-01-27 at 11:44 +0100, Ingo Molnar wrote:
> * Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote:
>
> > On Fri, 2012-01-27 at 11:27 +0100, Ingo Molnar wrote:
> >
> > > On Core2 CPUs there's PEBS so 'p' will work, but there's no
> > > LBR so the IP-rewinding does not work.
> >
> > Not on his thing.. PEBS is a trainwreck on model 15.
>
> ok - i have a model 23, there it works:
>
> [ 0.044260] CPU0: Intel(R) Core(TM)2 Duo CPU T9600 @ 2.80GHz stepping 06
> [ 0.044996] Performance Events: PEBS fmt0+, Core2 events, Intel PMU driver.

Right, only model 15 the very first core2 chips were badly broken, they
fixed it in the shrink (model 22,23,29).

And as you know, something got screwy in SNB (model 42) so that's got
PEBS fully disabled until further notice as well.
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