Re: [PATCH 5/8] perf tools: Get precise_ip from the pmu config

Andi Kleen
2019-03-05T16:40:21Z

On Tue, Mar 05, 2019 at 05:28:54PM +0100, Jiri Olsa wrote:
> On Tue, Mar 05, 2019 at 08:13:19AM -0800, Andi Kleen wrote:
> > On Tue, Mar 05, 2019 at 04:25:33PM +0100, Jiri Olsa wrote:
> > > Getting precise_ip field from the perf_pmu::max_precise
> > > config read from sysfs. If it's not available falling
> > > back to current detection function.
> >
> > max_precise depends on the event. This won't work for all
> > events. For example only instructions and cycles support
> > ppp
>
> I'm getting precise_ip=3 on mem-* events as well, that's why I
> was fixing this.. now it's not working for any event

I don't think it means anything for mem-*

There's some support for it on Goldmont plus for other events,
but it doesn't support mem-*. On big core it's only
for instructions and cycles, all implemented with the same
event. All other PEBS events only have two levels
switching between the two IPs.

-Andi