Re: [PATCH] tools/perf/metricgroup: Fix printing event names of metric group with multiple events

[Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>]

Em Wed, Dec 04, 2019 at 12:25:22PM +0530, Ravi Bangoria escreveu:
> 
> 
> On 11/20/19 2:10 PM, Kajol Jain wrote:
> > Commit f01642e4912b ("perf metricgroup: Support multiple
> > events for metricgroup") introduced support for multiple events
> > in a metric group. But with the current upstream, metric events
> > names are not printed properly
> > 
> > In power9 platform:
> > command:# ./perf stat --metric-only -M translation -C 0 -I 1000 sleep 2
> >       1.000208486
> >       2.000368863
> >       2.001400558
> > 
> > Similarly in skylake platform:
> > command:./perf stat --metric-only -M Power -I 1000
> >       1.000579994
> >       2.002189493
> > 
> > With current upstream version, issue is with event name comparison
> > logic in find_evsel_group(). Current logic is to compare events
> > belonging to a metric group to the events in perf_evlist.
> > Since the break statement is missing in the loop used for comparison
> > between metric group and perf_evlist events, the loop continues to
> > execute even after getting a pattern match, and end up in discarding
> > the matches.
> > Incase of single metric event belongs to metric group, its working fine,
> > because in case of single event once it compare all events it reaches to
> > end of perf_evlist.
> > 
> > Example for single metric event in power9 platform
> > command:# ./perf stat --metric-only  -M branches_per_inst -I 1000 sleep 1
> >       1.000094653                  0.2
> >       1.001337059                  0.0
> > 
> > Patch fixes the issue by making sure once we found all events
> > belongs to that metric event matched in find_evsel_group(), we
> > successfully break from that loop by adding corresponding condition.
> > 
> > With this patch:
> > In power9 platform:
> > 
> > command:# ./perf stat --metric-only -M translation -C 0 -I 1000 sleep 2
> > result:#           time derat_4k_miss_rate_percent  derat_4k_miss_ratio
> >       derat_miss_ratio derat_64k_miss_rate_percent derat_64k_miss_ratio
> >           dslb_miss_rate_percent islb_miss_rate_percent
> >       1.000135672                         0.0                  0.3
> >                    1.0                          0.0                  0.2
> >                   0.0                     0.0
> >       2.000380617                         0.0                  0.0
> >                                                0.0                  0.0
> >                  0.0                     0.0
> > 
> > command:# ./perf stat --metric-only -M Power -I 1000
> > 
> > Similarly in skylake platform:
> > result:#           time    Turbo_Utilization    C3_Core_Residency
> >              C6_Core_Residency    C7_Core_Residency     C2_Pkg_Residency
> >               C3_Pkg_Residency     C6_Pkg_Residency     C7_Pkg_Residency
> >       1.000563580                  0.3                  0.0
> >                    2.6                44.2                 21.9
> >                    0.0                  0.0                  0.0
> >       2.002235027                  0.4                  0.0
> >                    2.7           43.0                 20.7
> >                    0.0                  0.0               0.0
> > 
> > Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
> > Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
> > Cc: Andi Kleen <ak@linux.intel.com>
> > Cc: Jiri Olsa <jolsa@kernel.org>
> > Cc: Kan Liang <kan.liang@linux.intel.com>
> > Cc: Peter Zijlstra <peterz@infradead.org>
> > Cc: Jin Yao <yao.jin@linux.intel.com>
> > Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
> > Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
> > Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
> 
> Fixes: f01642e4912b ("perf metricgroup: Support multiple events for metricgroup")
> Reviewed-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>

Tested on a Skylake machine and applied.

> But while looking at the patch, I found that, commit f01642e4912b
> has (again) screwed up logic for metric with overlapping events.

Is someone looking into this?
 
>   $ sudo ./perf stat -M UPI,IPC sleep 1
> 
>    Performance counter stats for 'sleep 1':
> 
>            948,650      uops_retired.retire_slots
>            866,182      inst_retired.any          #      0.7 IPC
>            866,182      inst_retired.any
>          1,175,671      cpu_clk_unhalted.thread
> 
> This also needs to be fixed.
> 
> Ravi

-- 

- Arnaldo