Re: [perf metricgroup] fcc9c5243c: perf-sanity-tests.Parse_and_process_metrics.fail

From: Ian Rogers
Date: Mon Oct 19 2020 - 12:23:56 EST


On Mon, Oct 19, 2020 at 2:51 AM John Garry <john.garry@xxxxxxxxxx> wrote:
>
> On 19/10/2020 00:30, Ian Rogers wrote:
> > On Sun, Oct 18, 2020 at 1:51 AM kernel test robot <rong.a.chen@xxxxxxxxx> wrote:
> >>
> >> Greeting,
> >>
> >> FYI, we noticed the following commit (built with gcc-9):
> >>
> >> commit: fcc9c5243c478f104014daf4d23db86098d2aef0 ("perf metricgroup: Hack a fix for aliases when covering multiple PMUs")
> >> url: https://github.com/0day-ci/linux/commits/John-Garry/perf-pmu-events-Support-event-aliasing-for-system-PMUs/20201008-182049
> >>
> >>
> >> in testcase: perf-sanity-tests
> >> version: perf-x86_64-c85fb28b6f99-1_20201008
> >> with following parameters:
> >>
> >> perf_compiler: gcc
> >> ucode: 0xdc
> >>
> >>
> >>
> >> on test machine: 4 threads Intel(R) Core(TM) i5-6500 CPU @ 3.20GHz with 32G memory
> >>
> >> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
> >
> > I believe this is a Skylake and there is a known bug in the Skylake
> > metric DRAM_Parallel_Reads as described here:
> > https://lore.kernel.org/lkml/CAP-5=fXejVaQa9qfW66cY77qB962+jbe8tT5bsLoOOcFmODnWQ@xxxxxxxxxxxxxx/
> > Fixing the bug needs more knowledge than what is available in manuals.
> > Hopefully Intel can take a look.
> >
> > Thanks,
> > Ian
>
> So this named patch ("perf metricgroup: Hack a fix for aliases...") is
> breaking test #67 on my machine also, which is a broadwell.

Thanks for taking a look John. If you want help you can send the
output of "perf test 67 -vvv" to me. It is possible Broadwell has
similar glitches in the json to Skylake. I tested the original test on
server parts as I can access them as cloud machines.

> I will have a look, but I was hoping that Ian would have a proper fix
> for this on top of ("perf metricgroup: Fix uncore metric expressions"),
> which now looks to be merged.

I still have these changes to look at in my inbox but I'm assuming
they're good :-) Sorry for not getting to them, but it's good they are
merged.

Thanks,
Ian

> Thanks!
>
> >
> >>
> >>
> >> If you fix the issue, kindly add following tag
> >> Reported-by: kernel test robot <rong.a.chen@xxxxxxxxx>
> >>
> >>
> >> 2020-10-16 19:31:52 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 67
> >> 67: Parse and process metrics : FAILED!
> >> 2020-10-16 19:31:52 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 68
> >> 68: x86 rdpmc : Ok
> >> 2020-10-16 19:31:52 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 69
> >> 69: Convert perf time to TSC : Ok
> >> 2020-10-16 19:31:52 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 70
> >> 70: DWARF unwind : Ok
> >> 2020-10-16 19:31:52 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 71
> >> 71: x86 instruction decoder - new instructions : Ok
> >> 2020-10-16 19:31:52 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 72
> >> 72: Intel PT packet decoder : Ok
> >> 2020-10-16 19:31:52 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 73
> >> 73: x86 bp modify : Ok
> >> 2020-10-16 19:31:53 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 74
> >> 74: probe libc's inet_pton & backtrace it with ping : Ok
> >> 2020-10-16 19:31:54 sudo /usr/src/perf_selftests-x86_64-rhel-8.3-fcc9c5243c478f104014daf4d23db86098d2aef0/tools/perf/perf test 75
> >> 75: Zstd perf.data compression/decompression : Ok
> >>
> >>
> >>
> >> To reproduce:
> >>
> >> git clone https://github.com/intel/lkp-tests.git
> >> cd lkp-tests
> >> bin/lkp install job.yaml # job file is attached in this email
> >> bin/lkp run job.yaml
> >>
> >>
> >>
> >> Thanks,
> >> Rong Chen
> >>
> > .
> >
>