Re: [PATCH 01/10] perf tools: Uniquify the event name if there's no other matched event

From: Jiri Olsa
Date: Thu Jun 07 2018 - 02:22:58 EST


On Wed, Jun 06, 2018 at 04:19:02PM -0700, Andi Kleen wrote:
> On Thu, Jun 07, 2018 at 12:15:04AM +0200, Jiri Olsa wrote:
> > Currently by default we try to match the user specified PMU
> > name to all PMU units available and use them to aggregate
> > all matched PMUs event counts into one 'pattern' event.
> >
> > While this is useful for uncore events, it screws up names
> > for other events, where this is not desirable, like:
> >
> > Before:
> > # perf stat -e cp/cpu-cycles/ kill
>
> I assume you mean cpU/cpu-cycles/
> >
> > Performance counter stats for 'kill':
> >
> > 1,573,757 cp/cpu-cycles/
> >
> > Keeping the pattern matching logic, but making the name unique
> > in case there's no other match found. That fixes the example
> > above and hopefully does not screw up anything else.
> >
> > After:
> > # perf stat -e cp/cpu-cycles/ kill
> >
> > Performance counter stats for 'kill':
> >
> > 1,573,757 cpu/cpu-cycles/
>
>
> The output is 100% identical?

nope, the U is actualy missing.. that's the thing, the patern
matching allows you to put 'cp' instead of 'cpu' and the final
output is screwed.. also the metrics won't match the proper event

jirka