perf tests: Add another metric parsing test

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
  ...

The test also defines its own list of metrics and tries to parse them.
It's handy for developing.

Committer notes:

Testing it:

  $ perf test fake
  10: PMU events                                            :
  10.4: Parsing of PMU event table metrics with fake PMUs   : FAILED!
  $ perf test -v fake |& tail
  parsing '(unc_p_freq_trans_cycles / unc_p_clockticks) * 100.'
  parsing '(unc_m_power_channel_ppd / unc_m_clockticks) * 100.'
  parsing '(unc_m_power_critical_throttle_cycles / unc_m_clockticks) * 100.'
  parsing '(unc_m_power_self_refresh / unc_m_clockticks) * 100.'
  parsing 'idq_uops_not_delivered.core / * (4 * cycles)'
  syntax error
  expr__parse failed
  test child finished with -1
  ---- end ----
  PMU events subtest 4: FAILED!
  $

And fix this error:

  tests/pmu-events.c:437:40: error: missing field 'idx' initializer [-Werror,-Wmissing-field-initializers]
        struct parse_events_error error = { 0 };

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200602214741.1218986-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

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,
+			  struct perf_pmu *fake_pmu)
 {
 	struct evlist *evlist;
 	int ret;
@@ -402,7 +403,7 @@ static int check_parse_id(const char *id, struct parse_events_error *error)
 	evlist = evlist__new();
 	if (!evlist)
 		return -ENOMEM;
-	ret = parse_events(evlist, id, error);
+	ret = __parse_events(evlist, id, error, fake_pmu);
 	evlist__delete(evlist);
 	return ret;
 }
@@ -411,7 +412,7 @@ static int check_parse_cpu(const char *id, bool same_cpu, struct pmu_event *pe)
 {
 	struct parse_events_error error = { .idx = 0, };
 
-	int ret = check_parse_id(id, &error);
+	int ret = check_parse_id(id, &error, NULL);
 	if (ret && same_cpu) {
 		pr_warning("Parse event failed metric '%s' id '%s' expr '%s'\n",
 			pe->metric_name, id, pe->metric_expr);
@@ -429,6 +430,18 @@ 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 = { .idx = 0, };
+	int ret = check_parse_id(id, &error, &perf_pmu__fake);
+
+	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)
@@ -498,6 +511,100 @@ 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'
+ * 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;
@@ -514,6 +621,10 @@ 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)