Re: [PATCH V6 08/17] perf tools: Add Intel PT support

[Arnaldo Carvalho de Melo]

Em Fri, Jun 26, 2015 at 04:47:39PM +0300, Adrian Hunter escreveu:
> On 26/06/15 16:41, Arnaldo Carvalho de Melo wrote:
> >> Another thing, the intel_bts implementation does not support
> >> "instructions" samples because there is no timing information to
> >> use to create periodic samples.  But callchains are added only
> >> to "instructions" samples so there are no callchains in 'perf report'
> >> for intel_bts.  The call information is still available for
> > 
> > Humm, so IOW, what you say is that we should refuse to run 'record' when
> > asking for callchains and intel_bts?
> 
> 'record' can record other events at the same time which can have callchains.
> e.g.
> 
> 	perf record -g --per-thread -e intel_bts//u,branch-misses:u ls

Right, what I was trying to say is that there are combinations where one
can ask for a callchain in record, it will act as if it did what was
asked for but then when report runs, no callchain will be available.

I guess we can check for that situation and warn the user.

- Arnaldo
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