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From:   Namhyung Kim <namhyung@kernel.org>
Date:   Thu, 23 Jun 2022 23:22:16 -0700
Message-ID: <CAM9d7ci8pLo=dKFgF8O8610eHTx532d+1TKTf18ibPMtdZp5Lg@mail.gmail.com>
Subject: Re: [PATCH v2] perf test: Add ARM SPE system wide test
To:     Leo Yan <leo.yan@linaro.org>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Ian Rogers <irogers@google.com>,
        linux-perf-users <linux-perf-users@vger.kernel.org>,
        John Garry <john.garry@huawei.com>,
        Will Deacon <will@kernel.org>,
        James Clark <james.clark@arm.com>,
        Mike Leach <mike.leach@linaro.org>,
        German Gomez <german.gomez@arm.com>
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Hi Leo,

On Fri, Jun 17, 2022 at 12:45 AM Leo Yan <leo.yan@linaro.org> wrote:
>
> On Fri, Jun 17, 2022 at 03:38:40PM +0800, Leo Yan wrote:
> > Hi Namhyung,
> >
> > On Thu, Jun 16, 2022 at 04:05:46PM -0700, Namhyung Kim wrote:
> >
> > [...]
> >
> > > +arm_spe_system_wide_test() {
> > > +   echo "Recording trace with system-wide mode $perfdata"
> > > +   perf record -o ${perfdata} -e arm_spe// -a \
> > > +           -- dd if=/dev/zero of=/dev/null count=100000 > /dev/null 2>&1
> > > +
> > > +   if [ $? != 0 ]; then
> > > +           arm_spe_report "SPE system-wide testing" 2
> > > +           return
> > > +   fi
> >
> > I am awared the root permission issue after I saw German's suggestion.
> >
> > If the snapshot test is passed, no matter the system wide test is passed
> > or not, we will always return 0 for 'passed' result.  But we might miss
> > to capture the system-wide testing failure.
> >
> > How about use 'dummy' event to verіfy the root permission?
> > (actually I referred to intel-pt test):
> >
> >         perf record -o ${perfdata} -B -N --no-bpf-event -e dummy:u -a true 2>&1 >/dev/null
> >         if [ $? != 0 ]; then
> >               arm_spe_report "SPE system-wide testing" 2
> >               return
> >         fi
> >
> >         perf record -o ${perfdata} -e arm_spe// -a \
> >                   -- dd if=/dev/zero of=/dev/null count=100000 > /dev/null 2>&1

Ok, will add the change.

Thanks,
Namhyung