Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20200921094610.83736-1-namhyung@kernel.org> <20200921094610.83736-3-namhyung@kernel.org>
In-Reply-To: <20200921094610.83736-3-namhyung@kernel.org>
From:   Namhyung Kim <namhyung@kernel.org>
Date:   Wed, 23 Sep 2020 07:57:43 +0900
Message-ID: <CAM9d7ci09Qrkc6w-ysCTD5ARAZNXb0rqAg+K6Xbn=KaHFQzM5g@mail.gmail.com>
Subject: Re: [PATCH 2/5] perf stat: Add --for-each-cgroup option
To:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@redhat.com>
Cc:     Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Stephane Eranian <eranian@google.com>,
        Andi Kleen <ak@linux.intel.com>,
        Ian Rogers <irogers@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, Sep 21, 2020 at 6:46 PM Namhyung Kim <namhyung@kernel.org> wrote:
>
> The --for-each-cgroup option is a syntax sugar to monitor large number
> of cgroups easily.  Current command line requires to list all the
> events and cgroups even if users want to monitor same events for each
> cgroup.  This patch addresses that usage by copying given events for
> each cgroup on user's behalf.
>
> For instance, if they want to monitor 6 events for 200 cgroups each
> they should write 1200 event names (with -e) AND 1200 cgroup names
> (with -G) on the command line.  But with this change, they can just
> specify 6 events and 200 cgroups with a new option.
>
> A simpler example below: It wants to measure 3 events for 2 cgroups
> ('A' and 'B').  The result is that total 6 events are counted like
> below.
>
>   $ ./perf stat -a -e cpu-clock,cycles,instructions --for-each-cgroup A,B sleep 1
>
>    Performance counter stats for 'system wide':
>
>               988.18 msec cpu-clock                 A #    0.987 CPUs utilized
>        3,153,761,702      cycles                    A #    3.200 GHz                      (100.00%)
>        8,067,769,847      instructions              A #    2.57  insn per cycle           (100.00%)
>               982.71 msec cpu-clock                 B #    0.982 CPUs utilized
>        3,136,093,298      cycles                    B #    3.182 GHz                      (99.99%)
>        8,109,619,327      instructions              B #    2.58  insn per cycle           (99.99%)
>
>          1.001228054 seconds time elapsed
>
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/perf/builtin-stat.c | 20 +++++++++-
>  tools/perf/util/cgroup.c  | 84 +++++++++++++++++++++++++++++++++++++++
>  tools/perf/util/cgroup.h  |  1 +
>  tools/perf/util/stat.h    |  1 +
>  4 files changed, 105 insertions(+), 1 deletion(-)

Oh, I've realized that I didn't update the man page..
I'll send v4 soon.

Thanks
Namhyung