Re: [PATCH 04/13] perf tests: Add another metric parsing test

Ian Rogers
2020-06-02T17:58:47Z

On Tue, Jun 2, 2020 at 4:51 AM Jiri Olsa <jolsa@kernel.org> wrote:
>
> The test goes through all metrics compiled for arch
> within pmu events and try to parse them.
>
> This test is different from 'test_parsing' in that
> we go through all the events in the current arch,
> not just one defined for current CPU model. Using
> 'fake_pmu' to parse events which do not have PMUs
> defined in the system.
>
> Say there's bad change in ivybridge metrics file, like:
>
> --- a/tools/perf/pmu-events/arch/x86/ivybridge/ivb-metrics.json
> +++ b/tools/perf/pmu-events/arch/x86/ivybridge/ivb-metrics.json
> @@ -8,7 +8,7 @@
> - "MetricExpr": "IDQ_UOPS_NOT_DELIVERED.CORE / (4 * ((
> + "MetricExpr": "IDQ_UOPS_NOT_DELIVERED.CORE / / (4 *
>
> the test fails with (on my kabylake laptop):
>
> $ perf test 'Parsing of PMU event table metrics with fake PMUs' -v
> parsing 'idq_uops_not_delivered.core / / (4 * (( ( cpu_clk_unh...
> syntax error, line 1
> expr__parse failed
> test child finished with -1
> ...

For this example as the problem is the expression, presumably this was
"passing" with test_parsing due to returning TEST_SKIP? I did this
initially so that we could get the test merged and then the metrics
fixed. I'd prefer if test_parsing were returning TEST_FAIL.

> The test also defines its own list of metrics and
> tries to parse them. It's handy for developing.
>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
> tools/perf/tests/pmu-events.c | 117 +++++++++++++++++++++++++++++++++-
> 1 file changed, 114 insertions(+), 3 deletions(-)
>
> diff --git a/tools/perf/tests/pmu-events.c b/tools/perf/tests/pmu-events.c
> index f65380d2066f..d3343827eb4d 100644
> --- a/tools/perf/tests/pmu-events.c
> +++ b/tools/perf/tests/pmu-events.c
> @@ -390,7 +390,8 @@ static bool is_number(const char *str)
> return errno == 0 && end_ptr != str;
> }
>
> -static int check_parse_id(const char *id, struct parse_events_error *error)
> +static int check_parse_id(const char *id, struct parse_events_error *error,
> + bool fake_pmu)
> {
> struct evlist *evlist;
> int ret;
> @@ -403,7 +404,7 @@ static int check_parse_id(const char *id, struct parse_events_error *error)
> if (!evlist)
> return -ENOMEM;
> memset(error, 0, sizeof(*error));
> - ret = parse_events(evlist, id, error, false);
> + ret = parse_events(evlist, id, error, fake_pmu);
> evlist__delete(evlist);
> return ret;
> }
> @@ -412,7 +413,7 @@ static int check_parse_cpu(const char *id, bool same_cpu, struct pmu_event *pe)
> {
> struct parse_events_error error;
>
> - int ret = check_parse_id(id, &error);
> + int ret = check_parse_id(id, &error, false);
> if (ret && same_cpu) {
> pr_warning("Parse event failed metric '%s' id '%s' expr '%s'\n",
> pe->metric_name, id, pe->metric_expr);
> @@ -430,6 +431,18 @@ static int check_parse_cpu(const char *id, bool same_cpu, struct pmu_event *pe)
> return ret;
> }
>
> +static int check_parse_fake(const char *id)
> +{
> + struct parse_events_error error;

nit: this reads funny as it isn't clear, without looking at
check_parse_id, that error is zero initialized.

Thanks,
Ian

> + int ret = check_parse_id(id, &error, true);
> +
> + free(error.str);
> + free(error.help);
> + free(error.first_str);
> + free(error.first_help);
> + return ret;
> +}
> +
> static void expr_failure(const char *msg,
> const struct pmu_events_map *map,
> const struct pmu_event *pe)
> @@ -499,6 +512,100 @@ static int test_parsing(void)
> return ret == 0 ? TEST_OK : TEST_SKIP;
> }
>
> +struct test_metric {
> + const char *str;
> +};
> +
> +static struct test_metric metrics[] = {
> + { "(unc_p_power_state_occupancy.cores_c0 / unc_p_clockticks) * 100." },
> + { "imx8_ddr0@read\\-cycles@ * 4 * 4", },
> + { "imx8_ddr0@axid\\-read\\,axi_mask\\=0xffff\\,axi_id\\=0x0000@ * 4", },
> + { "(cstate_pkg@c2\\-residency@ / msr@tsc@) * 100", },
> + { "(imx8_ddr0@read\\-cycles@ + imx8_ddr0@write\\-cycles@)", },
> +};
> +
> +static int metric_parse_fake(const char *str)
> +{
> + struct expr_parse_ctx ctx;
> + struct hashmap_entry *cur;
> + double result;
> + int ret = -1;
> + size_t bkt;
> + int i;
> +
> + pr_debug("parsing '%s'\n", str);
> +
> + expr__ctx_init(&ctx);
> + if (expr__find_other(str, NULL, &ctx, 0) < 0) {
> + pr_err("expr__find_other failed\n");
> + return -1;
> + }
> +
> + /*
> + * Add all ids with a made up value. The value may
> + * trigger divide by zero when subtracted and so try to
> + * make them unique.
> + */
> + i = 1;
> + hashmap__for_each_entry((&ctx.ids), cur, bkt)
> + expr__add_id(&ctx, strdup(cur->key), i++);
> +
> + hashmap__for_each_entry((&ctx.ids), cur, bkt) {
> + if (check_parse_fake(cur->key)) {
> + pr_err("check_parse_fake failed\n");
> + goto out;
> + }
> + }
> +
> + if (expr__parse(&result, &ctx, str, 1))
> + pr_err("expr__parse failed\n");
> + else
> + ret = 0;
> +
> +out:
> + expr__ctx_clear(&ctx);
> + return ret;
> +}
> +
> +/*
> + * Parse all the metrics for current architecture,
> + * or all defined cpus via the 'fake_pmu' bool
> + * in parse_events.
> + */
> +static int test_parsing_fake(void)
> +{
> + struct pmu_events_map *map;
> + struct pmu_event *pe;
> + unsigned int i, j;
> + int err = 0;
> +
> + for (i = 0; i < ARRAY_SIZE(metrics); i++) {
> + err = metric_parse_fake(metrics[i].str);
> + if (err)
> + return err;
> + }
> +
> + i = 0;
> + for (;;) {
> + map = &pmu_events_map[i++];
> + if (!map->table)
> + break;
> + j = 0;
> + for (;;) {
> + pe = &map->table[j++];
> + if (!pe->name && !pe->metric_group && !pe->metric_name)
> + break;
> + if (!pe->metric_expr)
> + continue;
> + err = metric_parse_fake(pe->metric_expr);
> + if (err)
> + return err;
> + }
> + }
> +
> + return 0;
> +}
> +
> static const struct {
> int (*func)(void);
> const char *desc;
> @@ -515,6 +622,10 @@ static const struct {
> .func = test_parsing,
> .desc = "Parsing of PMU event table metrics",
> },
> + {
> + .func = test_parsing_fake,
> + .desc = "Parsing of PMU event table metrics with fake PMUs",
> + },
> };
>
> const char *test__pmu_events_subtest_get_desc(int subtest)
> --
> 2.25.4
>