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References: <20220803150744.133128-1-leo.yan@linaro.org>
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From:   Ian Rogers <irogers@google.com>
Date:   Wed, 3 Aug 2022 16:06:04 -0700
Message-ID: <CAP-5=fWArHKrxu80WKZystkEDFW_jhuU02m89S8tXkqvOChpoA@mail.gmail.com>
Subject: Re: [PATCH v1] perf test: Introduce script for data symbol parsing
To:     Leo Yan <leo.yan@linaro.org>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org
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On Wed, Aug 3, 2022 at 8:07 AM Leo Yan <leo.yan@linaro.org> wrote:
>
> This commit introduces a shell script for data symbol parsing.
>
> The testing is designed a data structure with 64-byte alignment, and it
> has two fields "data1" and "data2", and other fields are reserved.
>
> Using "perf mem" command, it records and reports memory samples for a
> workload with 1 second duration.  If have no any memory sample for the
> data structure "buf1", it reports failure;  and any memory accessing for
> the data structure is not for "data1" and "data2" filed, it also means
> the wrong data symbol parsing and returns failure.
>
> Signed-off-by: Leo Yan <leo.yan@linaro.org>
> ---
>  tools/perf/tests/shell/test_data_symbol.sh | 94 ++++++++++++++++++++++
>  1 file changed, 94 insertions(+)
>  create mode 100755 tools/perf/tests/shell/test_data_symbol.sh
>
> diff --git a/tools/perf/tests/shell/test_data_symbol.sh b/tools/perf/tests/shell/test_data_symbol.sh
> new file mode 100755
> index 000000000000..7039dae4e087
> --- /dev/null
> +++ b/tools/perf/tests/shell/test_data_symbol.sh
> @@ -0,0 +1,94 @@
> +#!/bin/bash
> +# Check perf data symbol parsing
> +
> +# SPDX-License-Identifier: GPL-2.0
> +# Leo Yan <leo.yan@linaro.org>, 2022
> +
> +skip_if_no_mem_event() {
> +       perf mem record -e list 2>&1 | egrep -q 'available' && return 0
> +       return 2
> +}
> +
> +skip_if_no_mem_event || exit 2
> +
> +# skip if there's no compiler
> +if ! [ -x "$(command -v cc)" ]; then
> +       echo "skip: no compiler, install gcc"
> +       exit 2
> +fi
> +
> +TEST_PROGRAM_SOURCE=$(mktemp /tmp/__perf_test.program.XXXXX.c)
> +TEST_PROGRAM=$(mktemp /tmp/__perf_test.program.XXXXX)
> +PERF_DATA=$(mktemp /tmp/__perf_test.perf.data.XXXXX)
> +
> +check_result() {
> +       # The memory report format is as below:
> +       #    99.92%  ...  [.] buf1+0x38  ...
> +       result=$(perf mem report -i ${PERF_DATA} --stdio 2>&1 | egrep "buf1" | \
> +               awk '{ for (i = 1; i <= NF; i++) { if ($i ~ /^buf1/) { print $i; break; } } }')
> +
> +       # Testing is failed if has no any sample for "buf1"
> +       [ -z "$result" ] && return 1
> +
> +       while IFS= read -r line; do
> +               # The "data1" and "data2" fields in structure "buf1" have
> +               # offset "0x0" and "0x38", returns failure if detect any
> +               # other offset value.
> +               if [ "$line" != "buf1+0x0" ] && [ "$line" != "buf1+0x38" ]; then
> +                       return 1
> +               fi
> +       done <<< "$result"
> +
> +       return 0
> +}
> +
> +cleanup_files()
> +{
> +       echo "Cleaning up files..."
> +       rm -f ${PERF_DATA}
> +       rm -f ${TEST_PROGRAM_SOURCE}
> +       rm -f ${TEST_PROGRAM}
> +}
> +
> +trap cleanup_files exit term int
> +
> +# compile test program
> +cat << EOF > $TEST_PROGRAM_SOURCE
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <unistd.h>
> +
> +typedef struct _buf {
> +       long data1;
> +       long reserved[6];
> +       long data2;
> +} buf __attribute__((aligned (64)));
> +
> +static buf buf1;
> +
> +int main() {
> +       int i;
> +       for (;;) {
> +               buf1.data1++;
> +               buf1.data2 += buf1.data1;
> +       }
> +       return 0;
> +}
> +EOF
> +
> +echo "Compiling test program..."
> +cc $TEST_PROGRAM_SOURCE -o $TEST_PROGRAM || exit 1
> +
> +echo "Recording workload..."
> +perf mem record --all-user -o ${PERF_DATA} -- $TEST_PROGRAM &
> +PERFPID=$!

I wonder here you could do:
TESTPID=$(ps -o pid -h --ppid "$PERFPID")

> +sleep 1
> +
> +kill $PERFPID
> +wait $PERFPID
> +# test program may leave an orphan process running the workload
> +killall $(basename $TEST_PROGRAM)

And then here kill $TESTPID to avoid the killall which worries me a little.

Thanks,
Ian

> +
> +check_result "$variable_name"
> +exit $?
> --
> 2.25.1
>