Re: [PATCH v4 0/3] JSON output for perf stat

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Tue, May 24, 2022 at 10:38:11PM -0700, Ian Rogers escreveu:
> Parsing the CSV or text output of perf stat can be problematic when
> new output is added (columns in CSV format). JSON names values and
> simplifies the job of parsing. Add a JSON output option to perf-stat
> then add unit test that parses and validates the output.
> 
> This is a resend of two v2 patches:
> https://lore.kernel.org/lkml/20210813220754.2104922-1-cjense@google.com/
> https://lore.kernel.org/lkml/20210813220936.2105426-1-cjense@google.com/
> with a few formatting changes and improvements to the linter.
> 
> The CSV test/linter is also added to ensure that CSV output doesn't regress:
> https://lore.kernel.org/lkml/20210813192108.2087512-1-cjense@google.com/

So, the JSON test is failing:

⬢[acme@toolbox perf]$ perf test -v JSON
Couldn't bump rlimit(MEMLOCK), failures may take place when creating BPF maps, etc
 90: perf stat JSON output linter                                    :
--- start ---
test child forked, pid 2626229
Checking json output: no args [Success]
Checking json output: system wide [Skip] parnoia and not root
Checking json output: system wide [Skip] parnoia and not root
Checking json output: interval Test failed for input:
{"interval" : 0.000506453, "counter-value" : "0.212360", "unit" : "msec", "event" : "task-clock:u", "event-runtime" : 212360, "pcnt-running" : 100.00, "metric-value" : 0.000212, "metric-unit" : "CPUs utilized"}

{"interval" : 0.000506453, "counter-value" : "0.000000", "unit" : "", "event" : "context-switches:u", "event-runtime" : 212360, "pcnt-running" : 100.00, "metric-value" : 0.000000, "metric-unit" : "/sec"}

{"interval" : 0.000506453, "counter-value" : "0.000000", "unit" : "", "event" : "cpu-migrations:u", "event-runtime" : 212360, "pcnt-running" : 100.00, "metric-value" : 0.000000, "metric-unit" : "/sec"}

{"interval" : 0.000506453, "counter-value" : "45.000000", "unit" : "", "event" : "page-faults:u", "event-runtime" : 212360, "pcnt-running" : 100.00, "metric-value" : 211.904313, "metric-unit" : "K/sec"}

{"interval" : 0.000506453, "counter-value" : "143761.000000", "unit" : "", "event" : "cycles:u", "event-runtime" : 217290, "pcnt-running" : 100.00, "metric-value" : 0.676968, "metric-unit" : "GHz"}

{"interval" : 0.000506453, "counter-value" : "456.000000", "unit" : "", "event" : "stalled-cycles-frontend:u", "event-runtime" : 217290, "pcnt-running" : 100.00, "metric-value" : 0.317193, "metric-unit" : "frontend cycles idle"}

{"interval" : 0.000506453, "counter-value" : "11639.000000", "unit" : "", "event" : "stalled-cycles-backend:u", "event-runtime" : 217290, "pcnt-running" : 100.00, "metric-value" : 8.096076, "metric-unit" : "backend cycles idle"}

{"interval" : 0.000506453, "counter-value" : "150684.000000", "unit" : "", "event" : "instructions:u", "event-runtime" : 217290, "pcnt-running" : 100.00, "metric-value" : 1.048156, "metric-unit" : "insn per cycle"}

{"interval" : 0.000506453, "metric-value" : 0.077241, "metric-unit" : "stalled cycles per insn"}

{"interval" : 0.000506453, "counter-value" : "29735.000000", "unit" : "", "event" : "branches:u", "event-runtime" : 217290, "pcnt-running" : 100.00, "metric-value" : 140.021661, "metric-unit" : "M/sec"}

{"interval" : 0.000506453, "counter-value" : "<not counted>", "unit" : "", "event" : "branch-misses:u", "event-runtime" : 0, "pcnt-running" : 0.00, "metric-value" : 0.000000, "metric-unit" : ""}

Traceback (most recent call last):
  File "/var/home/acme/git/perf/./tools/perf/tests/shell/lib/perf_json_output_lint.py", line 91, in <module>
    check_json_output(expected_items)
  File "/var/home/acme/git/perf/./tools/perf/tests/shell/lib/perf_json_output_lint.py", line 52, in check_json_output
    raise RuntimeError(f'wrong number of fields. counted {count} expected {expected_items}'
RuntimeError: wrong number of fields. counted 2 expected 7 in '{"interval" : 0.000506453, "metric-value" : 0.077241, "metric-unit" : "stalled cycles per insn"}
'
test child finished with -1
---- end ----
perf stat JSON output linter: FAILED!
⬢[acme@toolbox perf]$

So please check this and resubmit.

My system is a fedora 35 silverblue toolbox.

⬢[acme@toolbox perf]$ rpm -q python3
python3-3.10.4-1.fc35.x86_64

- Arnaldo