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

From: Jin, Yao
Date: Mon Oct 19 2020 - 07:50:00 EST


Hi Garry, Hi Ian,

On 10/19/2020 5:48 PM, John Garry 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.

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.

Thanks!


I just think they are different issues.

On my KBL client, the perf test #67 is passed.

But DRAM_Parallel_Reads does have issue.

root@kbl-ppc:~# perf stat -M DRAM_Parallel_Reads -- sleep 1
event syntax error: '{arb/event=0x80,umask=0x2/,arb/event=0x80,umask=0x2,thresh=1/}:W'
\___ unknown term 'thresh' for pmu 'uncore_arb'

valid terms: event,edge,inv,umask,cmask,config,config1,config2,name,period,percore

Initial error:
event syntax error: '..umask=0x2/,arb/event=0x80,umask=0x2,thresh=1/}:W'
\___ Cannot find PMU `arb'. Missing kernel support?

Usage: perf stat [<options>] [<command>]

-M, --metrics <metric/metric group list>
monitor specified metrics or metric groups (separated by ,)

I have a patch to fix DRAM_Parallel_Reads.

After:

root@kbl-ppc:~# perf stat -M MEM_Parallel_Reads -- sleep 1

Performance counter stats for 'system wide':

3,043,952 arb/event=0x80,umask=0x2/ # 1.00 MEM_Parallel_Reads

1.000879932 seconds time elapsed

I will post the patch later.

Thanks
Jin Yao




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

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