Re: [PATCH] perf: test: Add support for testing JSON generated by perf data command

[Namhyung Kim]

Hello,

On Wed, May 17, 2023 at 12:57 PM Ian Rogers <irogers@xxxxxxxxxx> wrote:
>
> On Wed, May 17, 2023 at 11:09 AM Anup Sharma <anupnewsmail@xxxxxxxxx> wrote:
> >
> > This commit adds support for testing the JSON output generated
> > by the perf data command's conversion to JSON functionality.
> > The test script now includes a validation step to ensure that
> > the resulting JSON file is contain valid data.
> >
> > As a newcomer to this community, any feedback on the implementation
> > is highly appreciated.
> >
> > Signed-off-by: Anup Sharma <anupnewsmail@xxxxxxxxx>
>
> Congratulations on sending your first patch! Anup is this summer's
> Google Summer-of-Code contributor for the Linux perf tool. I'm sure
> everyone on the lists is looking forward to your contributions!

+1

>
> > ---
> >  .../shell/test_perf_data_converter_json.sh    | 64 +++++++++++++++++++
> >  1 file changed, 64 insertions(+)
> >  create mode 100755 tools/perf/tests/shell/test_perf_data_converter_json.sh
> >
> > diff --git a/tools/perf/tests/shell/test_perf_data_converter_json.sh b/tools/perf/tests/shell/test_perf_data_converter_json.sh
> > new file mode 100755
> > index 000000000000..88db96e38925
> > --- /dev/null
> > +++ b/tools/perf/tests/shell/test_perf_data_converter_json.sh
> > @@ -0,0 +1,64 @@
> > +#!/bin/sh
> > +# perf data json converter test
> > +# SPDX-License-Identifier: GPL-2.0

You may want to run shellcheck when you write a shell script.

> > +
> > +set -e
> > +
> > +err=0
> > +perfdata=$(mktemp /tmp/__perf_test.perf.data.XXXXX)
> > +result=$(mktemp /tmp/__perf_test.output.json.XXXXX)
> > +
> > +cleanup()
> > +{
> > +       rm -f ${perfdata}
> > +       rm -f ${result}
> > +       trap - exit term int
> > +}
> > +
> > +trap_cleanup()
> > +{
> > +       cleanup
> > +       exit ${err}
> > +}
> > +trap trap_cleanup exit term int
> > +
> > +check()
> > +{
> > +       if [ `id -u` != 0 ]; then
> > +               echo "[Skip] No root permission"

I don't think we actually need root permission for this test.

> > +               err=2
> > +               exit
> > +       fi
> > +}
> > +
> > +test_json()
> > +{
> > +       echo "Testing perf data convertion to JSON"
> > +       perf record -o $perfdata -F 99 -a -g -- sleep 1 > /dev/null 2>&1

The -a/--system-wide option requires root permission usually.
We can run perf record in per-task mode instead.  Please remove the -a
option and run some other command instead of 'sleep 1'.  The perf tool
has a couple of test workloads and benchmark programs.  So you can try
something like

  perf record -o $perfdata -F 99 -g -- perf test -w noploop

or

  perf record -o $perfdata -F 99 -g -- perf bench sched messaging

Thanks,
Namhyung


> > +       perf data convert --to-json $result --force -i $perfdata >/dev/null 2>&1
> > +       echo "Perf Data Converter to JSON [SUCCESS]"
> > +}
> > +
> > +validate_json_format()
> > +{
> > +       echo "Testing perf data converted to JSON format"
> > +       if [ -f "${result}" ]; then
>
> It can be a good idea to test for failure and early exit. It would
> avoid being as indented in the following if.
>
> > +               if jq '.' "${result}" > /dev/null 2>&1; then
>
> This assumes the jq program is available and it isn't by default on my
> distribution. We could test:
> if ! which jq; then
> but it may be better to depend on Python and json.loads - Python is
> already a dependency for a number of the tests.
>
> Thanks,
> Ian
>
> > +                   echo "The file contains valid JSON format [SUCCESS]"
> > +               else
> > +                   echo "The file does not contain valid JSON format [FAILED]"
> > +                   err=1
> > +               fi
> > +           else
> > +               echo "File not found [FAILED]"
> > +               err=2
> > +               exit
> > +           fi
> > +}
> > +
> > +check
> > +
> > +test_json
> > +validate_json_format
> > +
> > +exit ${err}
> > --
> > 2.34.1
> >