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Date:   Fri, 17 Jun 2022 15:45:17 +0800
From:   Leo Yan <leo.yan@linaro.org>
To:     Namhyung Kim <namhyung@kernel.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@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>
Subject: Re: [PATCH v2] perf test: Add ARM SPE system wide test
Message-ID: <20220617074517.GB45710@leoy-ThinkPad-X240s>
References: <20220616230546.1390813-1-namhyung@kernel.org>
 <20220617073840.GA45710@leoy-ThinkPad-X240s>
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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 ${tmpfile} -B -N --no-bpf-event -e dummy:u -a true 2>&1 >/dev/null

Sorry for typo, s/tmpfile/perfdata/

>         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