Re: [PATCH v4 2/3] perf stat: Add JSON output option

From: Ian Rogers <irogers@google.com>
To: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>,
	Kan Liang <kan.liang@linux.intel.com>,
	Zhengjun Xing <zhengjun.xing@linux.intel.com>,
	Sandipan Das <sandipan.das@amd.com>,
	Claire Jensen <cjense@google.com>, Alyssa Ross <hi@alyssa.is>,
	Like Xu <likexu@tencent.com>, James Clark <james.clark@arm.com>,
	Florian Fischer <florian.fischer@muhq.space>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	linux-perf-users <linux-perf-users@vger.kernel.org>,
	Claire Jensen <clairej735@gmail.com>,
	Stephane Eranian <eranian@google.com>
Subject: Re: [PATCH v4 2/3] perf stat: Add JSON output option
Date: Tue, 31 May 2022 16:18:26 -0700	[thread overview]
Message-ID: <CAP-5=fXu5rSV6C=WCs3bkCuaXknoKZv6o0O5gGAJKeLcAFuVcA@mail.gmail.com> (raw)
In-Reply-To: <CAP-5=fXcskdtN_dz5jcVywq8S1=pC5TdEN25LcEXzd0Gyk+o+w@mail.gmail.com>

On Tue, May 31, 2022 at 4:13 PM Ian Rogers <irogers@google.com> wrote:
>
> On Tue, May 31, 2022 at 3:46 PM Namhyung Kim <namhyung@kernel.org> wrote:
> >
> > Hi Ian,
> >
> > On Tue, May 24, 2022 at 10:38 PM Ian Rogers <irogers@google.com> wrote:
> > >
> > > From: Claire Jensen <cjense@google.com>
> > >
> > > CSV output is tricky to format and column layout changes are susceptible
> > > to breaking parsers. New JSON-formatted output has variable names to
> > > identify fields that are consistent and informative, making
> > > the output parseable.
> > >
> > > CSV output example:
> > >
> > > 1.20,msec,task-clock:u,1204272,100.00,0.697,CPUs utilized
> > > 0,,context-switches:u,1204272,100.00,0.000,/sec
> > > 0,,cpu-migrations:u,1204272,100.00,0.000,/sec
> > > 70,,page-faults:u,1204272,100.00,58.126,K/sec
> > >
> > > JSON output example:
> > >
> > > {"counter-value" : "3805.723968", "unit" : "msec", "event" :
> > > "cpu-clock", "event-runtime" : 3805731510100.00, "pcnt-running"
> > > : 100.00, "metric-value" : 4.007571, "metric-unit" : "CPUs utilized"}
> > > {"counter-value" : "6166.000000", "unit" : "", "event" :
> > > "context-switches", "event-runtime" : 3805723045100.00, "pcnt-running"
> > > : 100.00, "metric-value" : 1.620191, "metric-unit" : "K/sec"}
> > > {"counter-value" : "466.000000", "unit" : "", "event" :
> > > "cpu-migrations", "event-runtime" : 3805727613100.00, "pcnt-running"
> > > : 100.00, "metric-value" : 122.447136, "metric-unit" : "/sec"}
> > > {"counter-value" : "208.000000", "unit" : "", "event" :
> > > "page-faults", "event-runtime" : 3805726799100.00, "pcnt-running"
> > > : 100.00, "metric-value" : 54.654516, "metric-unit" : "/sec"}
> > >
> > > Also added documentation for JSON option.
> > > There is some tidy up of CSV code including a potential memory over run
> > > in the os.nfields set up. To facilitate this an AGGR_MAX value is added.
> > >
> > > Signed-off-by: Claire Jensen <cjense@google.com>
> >
> > Your sign-off as well?
>
> Doh:
> Signed-off-by: Ian Rogers <irogers@google.com>
>
> Thanks,
> Ian

Actually, this was fixed in V5:
https://lore.kernel.org/lkml/20220526224515.4088240-1-irogers@google.com/

Thanks,
Ian

> > Anyway, I think there are places to clean up this part of code
> > more but that's not a part of the work.  Maybe I need to find
> > some time to do that later.
> >
> > Acked-by: Namhyung Kim <namhyung@kernel.org>
> >
> > Thanks,
> > Namhyung