Re: [PATCH v2 2/2] perf stat: Support regex pattern in --for-each-cgroup

[Namhyung Kim]

Hi Jiri,

On Mon, Oct 26, 2020 at 8:40 PM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> On Sat, Oct 24, 2020 at 11:59:18AM +0900, Namhyung Kim wrote:
> > To make the command line even more compact with cgroups, support regex
> > pattern matching in cgroup names.
> >
> >   $ perf stat -a -e cpu-clock,cycles --for-each-cgroup ^foo sleep 1
> >
> >           3,000.73 msec cpu-clock                 foo #    2.998 CPUs utilized
> >     12,530,992,699      cycles                    foo #    7.517 GHz                      (100.00%)
> >           1,000.61 msec cpu-clock                 foo/bar #    1.000 CPUs utilized
> >      4,178,529,579      cycles                    foo/bar #    2.506 GHz                      (100.00%)
> >           1,000.03 msec cpu-clock                 foo/baz #    0.999 CPUs utilized
> >      4,176,104,315      cycles                    foo/baz #    2.505 GHz                      (100.00%)
>
> just curious.. there was another foo/XXX group using the
> rest of the cycles, right?

No, if so it should be displayed too.  But actually there was a process
in the foo cgroup itself.

>
> also perhaps we want to warn if there's no match found:
>
>         $ sudo ./perf stat -a -e cpu-clock,cycles --for-each-cgroup ^foo sleep 1
>
>          Performance counter stats for 'system wide':
>
>
>                1.002375575 seconds time elapsed
>

Right, will check this case.

Thanks
Namhyung