perf test: Add hwmon "PMU" test

Based on a mix of the sysfs PMU test (for creating the reference
files) and the tool PMU test, test that parsing given hwmon events
with there aliases creates the expected config values.

Signed-off-by: Ian Rogers <[e-mail]>
Cc: Ravi Bangoria <[e-mail]>
Cc: Yoshihiro Furudera <[e-mail]>
Cc: Howard Chu <[e-mail]>
Cc: Ze Gao <[e-mail]>
Cc: Changbin Du <[e-mail]>
Cc: Junhao He <[e-mail]>
Cc: Weilin Wang <[e-mail]>
Cc: James Clark <[e-mail]>
Cc: Oliver Upton <[e-mail]>
Cc: Athira Jajeev <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Namhyung Kim <[e-mail]>

tools/perf/tests/hwmon_pmu.c

···
 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
 #include "debug.h"
+#include "evlist.h"
 #include "hwmon_pmu.h"
+#include "parse-events.h"
 #include "tests.h"
+#include <fcntl.h>
+#include <sys/stat.h>
 #include <linux/compiler.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
+
+static const struct test_event {
+	const char *name;
+	const char *alias;
+	long config;
+} test_events[] = {
+	{
+		"temp_test_hwmon_event1",
+		"temp1",
+		0xA0001,
+	},
+	{
+		"temp_test_hwmon_event2",
+		"temp2",
+		0xA0002,
+	},
+};
+
+/* Cleanup test PMU directory. */
+static int test_pmu_put(const char *dir, struct perf_pmu *hwm)
+{
+	char buf[PATH_MAX + 20];
+	int ret;
+
+	if (scnprintf(buf, sizeof(buf), "rm -fr %s", dir) < 0) {
+		pr_err("Failure to set up buffer for \"%s\"\n", dir);
+		return -EINVAL;
+	}
+	ret = system(buf);
+	if (ret)
+		pr_err("Failure to \"%s\"\n", buf);
+
+	perf_pmu__delete(hwm);
+	return ret;
+}
+
+/*
+ * Prepare test PMU directory data, normally exported by kernel at
+ * /sys/class/hwmon/hwmon<number>/. Give as input a buffer to hold the file
+ * path, the result is PMU loaded using that directory.
+ */
+static struct perf_pmu *test_pmu_get(char *dir, size_t sz)
+{
+	const char *test_hwmon_name_nl = "A test hwmon PMU\n";
+	const char *test_hwmon_name = "A test hwmon PMU";
+	/* Simulated hwmon items. */
+	const struct test_item {
+		const char *name;
+		const char *value;
+	} test_items[] = {
+		{ "temp1_label", "test hwmon event1\n", },
+		{ "temp1_input", "40000\n", },
+		{ "temp2_label", "test hwmon event2\n", },
+		{ "temp2_input", "50000\n", },
+	};
+	int dirfd, file;
+	struct perf_pmu *hwm = NULL;
+	ssize_t len;
+
+	/* Create equivalent of sysfs mount point. */
+	scnprintf(dir, sz, "/tmp/perf-hwmon-pmu-test-XXXXXX");
+	if (!mkdtemp(dir)) {
+		pr_err("mkdtemp failed\n");
+		dir[0] = '\0';
+		return NULL;
+	}
+	dirfd = open(dir, O_DIRECTORY);
+	if (dirfd < 0) {
+		pr_err("Failed to open test directory \"%s\"\n", dir);
+		goto err_out;
+	}
+
+	/* Create the test hwmon directory and give it a name. */
+	if (mkdirat(dirfd, "hwmon1234", 0755) < 0) {
+		pr_err("Failed to mkdir hwmon directory\n");
+		goto err_out;
+	}
+	file = openat(dirfd, "hwmon1234/name", O_WRONLY | O_CREAT, 0600);
+	if (!file) {
+		pr_err("Failed to open for writing file \"name\"\n");
+		goto err_out;
+	}
+	len = strlen(test_hwmon_name_nl);
+	if (write(file, test_hwmon_name_nl, len) < len) {
+		close(file);
+		pr_err("Failed to write to 'name' file\n");
+		goto err_out;
+	}
+	close(file);
+
+	/* Create test hwmon files. */
+	for (size_t i = 0; i < ARRAY_SIZE(test_items); i++) {
+		const struct test_item *item = &test_items[i];
+
+		file = openat(dirfd, item->name, O_WRONLY | O_CREAT, 0600);
+		if (!file) {
+			pr_err("Failed to open for writing file \"%s\"\n", item->name);
+			goto err_out;
+		}
+
+		if (write(file, item->value, strlen(item->value)) < 0) {
+			pr_err("Failed to write to file \"%s\"\n", item->name);
+			close(file);
+			goto err_out;
+		}
+		close(file);
+	}
+
+	/* Make the PMU reading the files created above. */
+	hwm = perf_pmus__add_test_hwmon_pmu(dirfd, "hwmon1234", test_hwmon_name);
+	if (!hwm)
+		pr_err("Test hwmon creation failed\n");
+
+err_out:
+	if (!hwm) {
+		test_pmu_put(dir, hwm);
+		if (dirfd >= 0)
+			close(dirfd);
+	}
+	return hwm;
+}
+
+static int do_test(size_t i, bool with_pmu, bool with_alias)
+{
+	const char *test_event = with_alias ? test_events[i].alias : test_events[i].name;
+	struct evlist *evlist = evlist__new();
+	struct evsel *evsel;
+	struct parse_events_error err;
+	int ret;
+	char str[128];
+	bool found = false;
+
+	if (!evlist) {
+		pr_err("evlist allocation failed\n");
+		return TEST_FAIL;
+	}
+
+	if (with_pmu)
+		snprintf(str, sizeof(str), "/%s/", test_event);
+	else
+		strlcpy(str, test_event, sizeof(str));
+
+	pr_debug("Testing '%s'\n", str);
+	parse_events_error__init(&err);
+	ret = parse_events(evlist, str, &err);
+	if (ret) {
+		evlist__delete(evlist);
+
+		pr_debug("FAILED %s:%d failed to parse event '%s', err %d\n",
+			 __FILE__, __LINE__, str, ret);
+		parse_events_error__print(&err, str);
+		ret = TEST_FAIL;
+		goto out;
+	}
+
+	ret = TEST_OK;
+	if (with_pmu ? (evlist->core.nr_entries != 1) : (evlist->core.nr_entries < 1)) {
+		pr_debug("FAILED %s:%d Unexpected number of events for '%s' of %d\n",
+			 __FILE__, __LINE__, str, evlist->core.nr_entries);
+		ret = TEST_FAIL;
+		goto out;
+	}
+
+	evlist__for_each_entry(evlist, evsel) {
+		if (!perf_pmu__is_hwmon(evsel->pmu))
+			continue;
+
+		if (evsel->core.attr.config != (u64)test_events[i].config) {
+			pr_debug("FAILED %s:%d Unexpected config for '%s', %lld != %ld\n",
+				__FILE__, __LINE__, str,
+				evsel->core.attr.config,
+				test_events[i].config);
+			ret = TEST_FAIL;
+			goto out;
+		}
+		found = true;
+	}
+
+	if (!found) {
+		pr_debug("FAILED %s:%d Didn't find hwmon event '%s' in parsed evsels\n",
+			 __FILE__, __LINE__, str);
+		ret = TEST_FAIL;
+	}
+
+out:
+	evlist__delete(evlist);
+	return ret;
+}
+
+static int test__hwmon_pmu(bool with_pmu)
+{
+	char dir[PATH_MAX];
+	struct perf_pmu *pmu = test_pmu_get(dir, sizeof(dir));
+	int ret = TEST_OK;
+
+	if (!pmu)
+		return TEST_FAIL;
+
+	for (size_t i = 0; i < ARRAY_SIZE(test_events); i++) {
+		ret = do_test(i, with_pmu, /*with_alias=*/false);
+
+		if (ret != TEST_OK)
+			break;
+
+		ret = do_test(i, with_pmu, /*with_alias=*/true);
+
+		if (ret != TEST_OK)
+			break;
+	}
+	test_pmu_put(dir, pmu);
+	return ret;
+}
+
+static int test__hwmon_pmu_without_pmu(struct test_suite *test __maybe_unused,
+				      int subtest __maybe_unused)
+{
+	return test__hwmon_pmu(/*with_pmu=*/false);
+}
+
+static int test__hwmon_pmu_with_pmu(struct test_suite *test __maybe_unused,
+				   int subtest __maybe_unused)
+{
+	return test__hwmon_pmu(/*with_pmu=*/false);
+}
 
 static int test__parse_hwmon_filename(struct test_suite *test __maybe_unused,
 				      int subtest __maybe_unused)
···
 
 static struct test_case tests__hwmon_pmu[] = {
 	TEST_CASE("Basic parsing test", parse_hwmon_filename),
+	TEST_CASE("Parsing without PMU name", hwmon_pmu_without_pmu),
+	TEST_CASE("Parsing with PMU name", hwmon_pmu_with_pmu),
 	{	.name = NULL, }
 };
 

tools/perf/util/pmus.c

···
 	return perf_pmu__lookup(&other_pmus, test_sysfs_dirfd, name, /*eager_load=*/true);
 }
 
+struct perf_pmu *perf_pmus__add_test_hwmon_pmu(int hwmon_dir,
+					       const char *sysfs_name,
+					       const char *name)
+{
+	return hwmon_pmu__new(&other_pmus, hwmon_dir, sysfs_name, name);
+}
+
 struct perf_pmu *perf_pmus__fake_pmu(void)
 {
 	static struct perf_pmu fake = {

tools/perf/util/pmus.h

···
 char *perf_pmus__default_pmu_name(void);
 
 struct perf_pmu *perf_pmus__add_test_pmu(int test_sysfs_dirfd, const char *name);
+struct perf_pmu *perf_pmus__add_test_hwmon_pmu(int hwmon_dir,
+					       const char *sysfs_name,
+					       const char *name);
 struct perf_pmu *perf_pmus__fake_pmu(void);
 
 #endif /* __PMUS_H */