Re: [PATCH v2] perf list: Display hybrid pmu events with cpu type

[John Garry]

On 19/10/2021 22:14, Arnaldo Carvalho de Melo wrote:
> Em Fri, Sep 03, 2021 at 10:52:39AM +0800, Jin Yao escreveu:
> > Add a new option '--cputype' to perf-list to display core-only pmu events
> > or atom-only pmu events.
> >
> > Each hybrid pmu event has been assigned with a pmu name, this patch
> > compares the pmu name before listing the result.
> >
> > For example,
> >
> > perf list --cputype atom
> > ...
> > cache:
> >    core_reject_l2q.any
> >         [Counts the number of request that were not accepted into the L2Q because the L2Q is FULL. Unit: cpu_atom]
> > ...
> >
> > The "Unit: cpu_atom" is displayed in the brief description section
> > to indicate this is an atom event.
> Thanks, applied.

It seems that this buggers "perf list" for uncore events on my arm64 
platform.

Before:

./perf list "uncore ddrc"
uncore ddrc:
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  flux_rcmd
 [DDRC read commands. Unit: hisi_sccl,ddrc]
  flux_rd
 [DDRC total read operations. Unit: hisi_sccl,ddrc]
  flux_wcmd
 [DDRC write commands. Unit: hisi_sccl,ddrc]
  flux_wr
 [DDRC total write operations. Unit: hisi_sccl,ddrc]
  pre_cmd
 [DDRC precharge commands. Unit: hisi_sccl,ddrc]
  rnk_chg
 [DDRC rank commands. Unit: hisi_sccl,ddrc]
  rw_chg
 [DDRC read and write changes. Unit: hisi_sccl,ddrc]


After:

./perf list "uncore ddrc"

uncore ddrc:
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,ddrc]
  act_cmd
 [DDRC active commands. Unit: hisi_sccl,dd

Notice how the events are repeated.

And then gets broken even worse later some point before v5.16-rc6 such 
that aliasing gets broken altogether.

./perf list  | grep hisi_sccl | grep act_cmd|  wc -l
16

Good should be 0.

I'll have a look. Obviously we need a test case to stop such breakages.

Thanks,
John