[PATCH v2 0/3] Add a runs-per-test flag

[PATCH v2 0/3] Add a runs-per-test flag

[Ian Rogers]

In the v1 patch Kan and I noted cleanup that would make the code
cleaner and less indented:
https://lore.kernel.org/lkml/20241109160219.49976-1-irogers@google.com/
Add patches doing some builtin-test.c cleanup and then add the
runs-per-test flag.

Ian Rogers (3):
  perf test: Rename functions and variables for better clarity
  perf test: Send list output to stdout rather than stderr
  perf test: Add a runs-per-test flag

 tools/perf/tests/builtin-test.c | 223 +++++++++++++++-----------------
 1 file changed, 107 insertions(+), 116 deletions(-)

-- 
2.47.1.613.gc27f4b7a9f-goog

[PATCH v2 1/3] perf test: Rename functions and variables for better clarity

[Ian Rogers]

The relationship between subtests and test cases is somewhat
confusing, so let's do away with the notion of sub-tests and switch to
just working with some number of test cases. Add a
test_suite__for_each_test_case as in many cases, except the special
one test case situation, the iteration can just be on all test
cases. Switch variable names to be more intention revealing of what
their value is.

This work was motivated by discussion with Kan where it was noted the
code is becoming overly indented:
https://lore.kernel.org/lkml/20241109160219.49976-1-irogers@google.com/
Unifying more of the sub-test/no-sub-tests avoids one level of
indentation in a number of places.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/builtin-test.c | 201 +++++++++++++++-----------------
 1 file changed, 93 insertions(+), 108 deletions(-)

diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index a5b9ccd0033a..c3e082efb7f4 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -149,58 +149,51 @@ static struct test_workload *workloads[] = {
 #define workloads__for_each(workload) \
 	for (unsigned i = 0; i < ARRAY_SIZE(workloads) && ({ workload = workloads[i]; 1; }); i++)
 
-static int num_subtests(const struct test_suite *t)
+#define test_suite__for_each_test_case(suite, idx)			\
+	for (idx = 0; (suite)->test_cases && (suite)->test_cases[idx].name != NULL; idx++)
+
+static int test_suite__num_test_cases(const struct test_suite *t)
 {
 	int num;
 
-	if (!t->test_cases)
-		return 0;
-
-	num = 0;
-	while (t->test_cases[num].name)
-		num++;
+	test_suite__for_each_test_case(t, num);
 
 	return num;
 }
 
-static bool has_subtests(const struct test_suite *t)
-{
-	return num_subtests(t) > 1;
-}
-
-static const char *skip_reason(const struct test_suite *t, int subtest)
+static const char *skip_reason(const struct test_suite *t, int test_case)
 {
 	if (!t->test_cases)
 		return NULL;
 
-	return t->test_cases[subtest >= 0 ? subtest : 0].skip_reason;
+	return t->test_cases[test_case >= 0 ? test_case : 0].skip_reason;
 }
 
-static const char *test_description(const struct test_suite *t, int subtest)
+static const char *test_description(const struct test_suite *t, int test_case)
 {
-	if (t->test_cases && subtest >= 0)
-		return t->test_cases[subtest].desc;
+	if (t->test_cases && test_case >= 0)
+		return t->test_cases[test_case].desc;
 
 	return t->desc;
 }
 
-static test_fnptr test_function(const struct test_suite *t, int subtest)
+static test_fnptr test_function(const struct test_suite *t, int test_case)
 {
-	if (subtest <= 0)
+	if (test_case <= 0)
 		return t->test_cases[0].run_case;
 
-	return t->test_cases[subtest].run_case;
+	return t->test_cases[test_case].run_case;
 }
 
-static bool test_exclusive(const struct test_suite *t, int subtest)
+static bool test_exclusive(const struct test_suite *t, int test_case)
 {
-	if (subtest <= 0)
+	if (test_case <= 0)
 		return t->test_cases[0].exclusive;
 
-	return t->test_cases[subtest].exclusive;
+	return t->test_cases[test_case].exclusive;
 }
 
-static bool perf_test__matches(const char *desc, int curr, int argc, const char *argv[])
+static bool perf_test__matches(const char *desc, int suite_num, int argc, const char *argv[])
 {
 	int i;
 
@@ -212,7 +205,7 @@ static bool perf_test__matches(const char *desc, int curr, int argc, const char
 		long nr = strtoul(argv[i], &end, 10);
 
 		if (*end == '\0') {
-			if (nr == curr + 1)
+			if (nr == suite_num + 1)
 				return true;
 			continue;
 		}
@@ -227,8 +220,8 @@ static bool perf_test__matches(const char *desc, int curr, int argc, const char
 struct child_test {
 	struct child_process process;
 	struct test_suite *test;
-	int test_num;
-	int subtest;
+	int suite_num;
+	int test_case_num;
 };
 
 static jmp_buf run_test_jmp_buf;
@@ -258,7 +251,7 @@ static int run_test_child(struct child_process *process)
 
 	pr_debug("--- start ---\n");
 	pr_debug("test child forked, pid %d\n", getpid());
-	err = test_function(child->test, child->subtest)(child->test, child->subtest);
+	err = test_function(child->test, child->test_case_num)(child->test, child->test_case_num);
 	pr_debug("---- end(%d) ----\n", err);
 
 err_out:
@@ -270,15 +263,16 @@ static int run_test_child(struct child_process *process)
 
 #define TEST_RUNNING -3
 
-static int print_test_result(struct test_suite *t, int i, int subtest, int result, int width,
-			     int running)
+static int print_test_result(struct test_suite *t, int curr_suite, int curr_test_case,
+			     int result, int width, int running)
 {
-	if (has_subtests(t)) {
+	if (test_suite__num_test_cases(t) > 1) {
 		int subw = width > 2 ? width - 2 : width;
 
-		pr_info("%3d.%1d: %-*s:", i + 1, subtest + 1, subw, test_description(t, subtest));
+		pr_info("%3d.%1d: %-*s:", curr_suite + 1, curr_test_case + 1, subw,
+			test_description(t, curr_test_case));
 	} else
-		pr_info("%3d: %-*s:", i + 1, width, test_description(t, subtest));
+		pr_info("%3d: %-*s:", curr_suite + 1, width, test_description(t, curr_test_case));
 
 	switch (result) {
 	case TEST_RUNNING:
@@ -288,7 +282,7 @@ static int print_test_result(struct test_suite *t, int i, int subtest, int resul
 		pr_info(" Ok\n");
 		break;
 	case TEST_SKIP: {
-		const char *reason = skip_reason(t, subtest);
+		const char *reason = skip_reason(t, curr_test_case);
 
 		if (reason)
 			color_fprintf(stderr, PERF_COLOR_YELLOW, " Skip (%s)\n", reason);
@@ -310,7 +304,7 @@ static void finish_test(struct child_test **child_tests, int running_test, int c
 {
 	struct child_test *child_test = child_tests[running_test];
 	struct test_suite *t;
-	int i, subi, err;
+	int curr_suite, curr_test_case, err;
 	bool err_done = false;
 	struct strbuf err_output = STRBUF_INIT;
 	int last_running = -1;
@@ -321,15 +315,15 @@ static void finish_test(struct child_test **child_tests, int running_test, int c
 		return;
 	}
 	t = child_test->test;
-	i = child_test->test_num;
-	subi = child_test->subtest;
+	curr_suite = child_test->suite_num;
+	curr_test_case = child_test->test_case_num;
 	err = child_test->process.err;
 	/*
 	 * For test suites with subtests, display the suite name ahead of the
 	 * sub test names.
 	 */
-	if (has_subtests(t) && subi == 0)
-		pr_info("%3d: %-*s:\n", i + 1, width, test_description(t, -1));
+	if (test_suite__num_test_cases(t) > 1 && curr_test_case == 0)
+		pr_info("%3d: %-*s:\n", curr_suite + 1, width, test_description(t, -1));
 
 	/*
 	 * Busy loop reading from the child's stdout/stderr that are set to be
@@ -338,10 +332,11 @@ static void finish_test(struct child_test **child_tests, int running_test, int c
 	if (err > 0)
 		fcntl(err, F_SETFL, O_NONBLOCK);
 	if (verbose > 1) {
-		if (has_subtests(t))
-			pr_info("%3d.%1d: %s:\n", i + 1, subi + 1, test_description(t, subi));
+		if (test_suite__num_test_cases(t) > 1)
+			pr_info("%3d.%1d: %s:\n", curr_suite + 1, curr_test_case + 1,
+				test_description(t, curr_test_case));
 		else
-			pr_info("%3d: %s:\n", i + 1, test_description(t, -1));
+			pr_info("%3d: %s:\n", curr_suite + 1, test_description(t, -1));
 	}
 	while (!err_done) {
 		struct pollfd pfds[1] = {
@@ -366,7 +361,8 @@ static void finish_test(struct child_test **child_tests, int running_test, int c
 					 */
 					fprintf(debug_file(), PERF_COLOR_DELETE_LINE);
 				}
-				print_test_result(t, i, subi, TEST_RUNNING, width, running);
+				print_test_result(t, curr_suite, curr_test_case, TEST_RUNNING,
+						  width, running);
 				last_running = running;
 			}
 		}
@@ -404,14 +400,14 @@ static void finish_test(struct child_test **child_tests, int running_test, int c
 		fprintf(stderr, "%s", err_output.buf);
 
 	strbuf_release(&err_output);
-	print_test_result(t, i, subi, ret, width, /*running=*/0);
+	print_test_result(t, curr_suite, curr_test_case, ret, width, /*running=*/0);
 	if (err > 0)
 		close(err);
 	zfree(&child_tests[running_test]);
 }
 
-static int start_test(struct test_suite *test, int i, int subi, struct child_test **child,
-		int width, int pass)
+static int start_test(struct test_suite *test, int curr_suite, int curr_test_case,
+		struct child_test **child, int width, int pass)
 {
 	int err;
 
@@ -419,17 +415,18 @@ static int start_test(struct test_suite *test, int i, int subi, struct child_tes
 	if (dont_fork) {
 		if (pass == 1) {
 			pr_debug("--- start ---\n");
-			err = test_function(test, subi)(test, subi);
+			err = test_function(test, curr_suite)(test, curr_test_case);
 			pr_debug("---- end ----\n");
-			print_test_result(test, i, subi, err, width, /*running=*/0);
+			print_test_result(test, curr_suite, curr_test_case, err, width,
+					  /*running=*/0);
 		}
 		return 0;
 	}
-	if (pass == 1 && !sequential && test_exclusive(test, subi)) {
+	if (pass == 1 && !sequential && test_exclusive(test, curr_test_case)) {
 		/* When parallel, skip exclusive tests on the first pass. */
 		return 0;
 	}
-	if (pass != 1 && (sequential || !test_exclusive(test, subi))) {
+	if (pass != 1 && (sequential || !test_exclusive(test, curr_test_case))) {
 		/* Sequential and non-exclusive tests were run on the first pass. */
 		return 0;
 	}
@@ -438,8 +435,8 @@ static int start_test(struct test_suite *test, int i, int subi, struct child_tes
 		return -ENOMEM;
 
 	(*child)->test = test;
-	(*child)->test_num = i;
-	(*child)->subtest = subi;
+	(*child)->suite_num = curr_suite;
+	(*child)->test_case_num = curr_test_case;
 	(*child)->process.pid = -1;
 	(*child)->process.no_stdin = 1;
 	if (verbose <= 0) {
@@ -479,19 +476,15 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
 	int err = 0;
 
 	for (struct test_suite **t = suites; *t; t++) {
-		int len = strlen(test_description(*t, -1));
+		int i, len = strlen(test_description(*t, -1));
 
 		if (width < len)
 			width = len;
 
-		if (has_subtests(*t)) {
-			for (int subi = 0, subn = num_subtests(*t); subi < subn; subi++) {
-				len = strlen(test_description(*t, subi));
-				if (width < len)
-					width = len;
-				num_tests++;
-			}
-		} else {
+		test_suite__for_each_test_case(*t, i) {
+			len = strlen(test_description(*t, i));
+			if (width < len)
+				width = len;
 			num_tests++;
 		}
 	}
@@ -510,7 +503,7 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
 				continue;
 
 			pr_debug3("Killing %d pid %d\n",
-				  child_test->test_num + 1,
+				  child_test->suite_num + 1,
 				  child_test->process.pid);
 			kill(child_test->process.pid, err);
 		}
@@ -526,47 +519,43 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
 	 */
 	for (int pass = 1; pass <= 2; pass++) {
 		int child_test_num = 0;
-		int i = 0;
+		int curr_suite = 0;
 
-		for (struct test_suite **t = suites; *t; t++) {
-			int curr = i++;
+		for (struct test_suite **t = suites; *t; t++, curr_suite++) {
+			int curr_test_case;
 
-			if (!perf_test__matches(test_description(*t, -1), curr, argc, argv)) {
+			if (!perf_test__matches(test_description(*t, -1), curr_suite, argc, argv)) {
 				/*
 				 * Test suite shouldn't be run based on
-				 * description. See if subtest should.
+				 * description. See if any test case should.
 				 */
 				bool skip = true;
 
-				for (int subi = 0, subn = num_subtests(*t); subi < subn; subi++) {
-					if (perf_test__matches(test_description(*t, subi),
-								curr, argc, argv))
+				test_suite__for_each_test_case(*t, curr_test_case) {
+					if (perf_test__matches(test_description(*t, curr_test_case),
+							       curr_suite, argc, argv)) {
 						skip = false;
+						break;
+					}
 				}
-
 				if (skip)
 					continue;
 			}
 
-			if (intlist__find(skiplist, i)) {
-				pr_info("%3d: %-*s:", curr + 1, width, test_description(*t, -1));
+			if (intlist__find(skiplist, curr_suite + 1)) {
+				pr_info("%3d: %-*s:", curr_suite + 1, width,
+					test_description(*t, -1));
 				color_fprintf(stderr, PERF_COLOR_YELLOW, " Skip (user override)\n");
 				continue;
 			}
 
-			if (!has_subtests(*t)) {
-				err = start_test(*t, curr, -1, &child_tests[child_test_num++],
-						 width, pass);
-				if (err)
-					goto err_out;
-				continue;
-			}
-			for (int subi = 0, subn = num_subtests(*t); subi < subn; subi++) {
-				if (!perf_test__matches(test_description(*t, subi),
-							curr, argc, argv))
+			test_suite__for_each_test_case(*t, curr_test_case) {
+				if (!perf_test__matches(test_description(*t, curr_test_case),
+							curr_suite, argc, argv))
 					continue;
 
-				err = start_test(*t, curr, subi, &child_tests[child_test_num++],
+				err = start_test(*t, curr_suite, curr_test_case,
+						 &child_tests[child_test_num++],
 						 width, pass);
 				if (err)
 					goto err_out;
@@ -592,23 +581,22 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
 
 static int perf_test__list(struct test_suite **suites, int argc, const char **argv)
 {
-	int i = 0;
+	int curr_suite = 0;
 
-	for (struct test_suite **t = suites; *t; t++) {
-		int curr = i++;
+	for (struct test_suite **t = suites; *t; t++, curr_suite++) {
+		int curr_test_case;
 
-		if (!perf_test__matches(test_description(*t, -1), curr, argc, argv))
+		if (!perf_test__matches(test_description(*t, -1), curr_suite, argc, argv))
 			continue;
 
-		pr_info("%3d: %s\n", i, test_description(*t, -1));
+		pr_info("%3d: %s\n", curr_suite + 1, test_description(*t, -1));
 
-		if (has_subtests(*t)) {
-			int subn = num_subtests(*t);
-			int subi;
+		if (test_suite__num_test_cases(*t) <= 1)
+			continue;
 
-			for (subi = 0; subi < subn; subi++)
-				pr_info("%3d:%1d: %s\n", i, subi + 1,
-					test_description(*t, subi));
+		test_suite__for_each_test_case(*t, curr_test_case) {
+			pr_info("%3d:%1d: %s\n", curr_suite + 1, curr_test_case + 1,
+				test_description(*t, curr_test_case));
 		}
 	}
 	return 0;
@@ -665,27 +653,24 @@ static struct test_suite **build_suites(void)
 	if (suites[2] == NULL)
 		suites[2] = create_script_test_suites();
 
-#define for_each_test(t)						\
+#define for_each_suite(suite)						\
 	for (size_t i = 0, j = 0; i < ARRAY_SIZE(suites); i++, j = 0)	\
-		while ((t = suites[i][j++]) != NULL)
+		while ((suite = suites[i][j++]) != NULL)
 
-	for_each_test(t)
+	for_each_suite(t)
 		num_suites++;
 
 	result = calloc(num_suites + 1, sizeof(struct test_suite *));
 
 	for (int pass = 1; pass <= 2; pass++) {
-		for_each_test(t) {
+		for_each_suite(t) {
 			bool exclusive = false;
+			int curr_test_case;
 
-			if (!has_subtests(t)) {
-				exclusive = test_exclusive(t, -1);
-			} else {
-				for (int subi = 0, subn = num_subtests(t); subi < subn; subi++) {
-					if (test_exclusive(t, subi)) {
-						exclusive = true;
-						break;
-					}
+			test_suite__for_each_test_case(t, curr_test_case) {
+				if (test_exclusive(t, curr_test_case)) {
+					exclusive = true;
+					break;
 				}
 			}
 			if ((!exclusive && pass == 1) || (exclusive && pass == 2))
@@ -693,7 +678,7 @@ static struct test_suite **build_suites(void)
 		}
 	}
 	return result;
-#undef for_each_test
+#undef for_each_suite
 }
 
 int cmd_test(int argc, const char **argv)
-- 
2.47.1.613.gc27f4b7a9f-goog

[PATCH v2 2/3] perf test: Send list output to stdout rather than stderr

[Ian Rogers]

Follow the workload listing in using stdout rather than
stderr. Correct the numbering of sub-tests to be 1.1 rather than 1:1.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/builtin-test.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index c3e082efb7f4..887f735da900 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -579,7 +579,7 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
 	return err;
 }
 
-static int perf_test__list(struct test_suite **suites, int argc, const char **argv)
+static int perf_test__list(FILE *fp, struct test_suite **suites, int argc, const char **argv)
 {
 	int curr_suite = 0;
 
@@ -589,13 +589,13 @@ static int perf_test__list(struct test_suite **suites, int argc, const char **ar
 		if (!perf_test__matches(test_description(*t, -1), curr_suite, argc, argv))
 			continue;
 
-		pr_info("%3d: %s\n", curr_suite + 1, test_description(*t, -1));
+		fprintf(fp, "%3d: %s\n", curr_suite + 1, test_description(*t, -1));
 
 		if (test_suite__num_test_cases(*t) <= 1)
 			continue;
 
 		test_suite__for_each_test_case(*t, curr_test_case) {
-			pr_info("%3d:%1d: %s\n", curr_suite + 1, curr_test_case + 1,
+			fprintf(fp, "%3d.%1d: %s\n", curr_suite + 1, curr_test_case + 1,
 				test_description(*t, curr_test_case));
 		}
 	}
@@ -721,7 +721,7 @@ int cmd_test(int argc, const char **argv)
 	argc = parse_options_subcommand(argc, argv, test_options, test_subcommands, test_usage, 0);
 	if (argc >= 1 && !strcmp(argv[0], "list")) {
 		suites = build_suites();
-		ret = perf_test__list(suites, argc - 1, argv + 1);
+		ret = perf_test__list(stdout, suites, argc - 1, argv + 1);
 		free(suites);
 		return ret;
 	}
-- 
2.47.1.613.gc27f4b7a9f-goog

[PATCH v2 3/3] perf test: Add a runs-per-test flag

[Ian Rogers]

To detect flakes it is useful to run tests more than once. Add a
runs-per-test flag that will run each test multiple times.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/builtin-test.c | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 887f735da900..729740c1e5e5 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -42,6 +42,8 @@
 static bool dont_fork;
 /* Fork the tests in parallel and wait for their completion. */
 static bool sequential;
+/* Number of times each test is run. */
+static unsigned int runs_per_test = 1;
 const char *dso_to_test;
 const char *test_objdump_path = "objdump";
 
@@ -485,7 +487,7 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
 			len = strlen(test_description(*t, i));
 			if (width < len)
 				width = len;
-			num_tests++;
+			num_tests += runs_per_test;
 		}
 	}
 	child_tests = calloc(num_tests, sizeof(*child_tests));
@@ -549,16 +551,18 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
 				continue;
 			}
 
-			test_suite__for_each_test_case(*t, curr_test_case) {
-				if (!perf_test__matches(test_description(*t, curr_test_case),
-							curr_suite, argc, argv))
-					continue;
-
-				err = start_test(*t, curr_suite, curr_test_case,
-						 &child_tests[child_test_num++],
-						 width, pass);
-				if (err)
-					goto err_out;
+			for (unsigned int run = 0; run < runs_per_test; run++) {
+				test_suite__for_each_test_case(*t, curr_test_case) {
+					if (!perf_test__matches(test_description(*t, curr_test_case),
+								curr_suite, argc, argv))
+						continue;
+
+					err = start_test(*t, curr_suite, curr_test_case,
+							 &child_tests[child_test_num++],
+							 width, pass);
+					if (err)
+						goto err_out;
+				}
 			}
 		}
 		if (!sequential) {
@@ -698,6 +702,8 @@ int cmd_test(int argc, const char **argv)
 		    "Do not fork for testcase"),
 	OPT_BOOLEAN('S', "sequential", &sequential,
 		    "Run the tests one after another rather than in parallel"),
+	OPT_UINTEGER('r', "runs-per-test", &runs_per_test,
+		     "Run each test the given number of times, default 1"),
 	OPT_STRING('w', "workload", &workload, "work", "workload to run for testing, use '--list-workloads' to list the available ones."),
 	OPT_BOOLEAN(0, "list-workloads", &list_workloads, "List the available builtin workloads to use with -w/--workload"),
 	OPT_STRING(0, "dso", &dso_to_test, "dso", "dso to test"),
-- 
2.47.1.613.gc27f4b7a9f-goog

Re: [PATCH v2 3/3] perf test: Add a runs-per-test flag

[Namhyung Kim]

On Tue, Jan 07, 2025 at 02:01:52PM -0800, Ian Rogers wrote:
> To detect flakes it is useful to run tests more than once. Add a
> runs-per-test flag that will run each test multiple times.

Does it change the output?  What if it sometimes succeeds and fails?
It'd be nice if you can add an example output in the commit log.

Also please update the documentation.

Thanks,
Namhyung

> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/perf/tests/builtin-test.c | 28 +++++++++++++++++-----------
>  1 file changed, 17 insertions(+), 11 deletions(-)
> 
> diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
> index 887f735da900..729740c1e5e5 100644
> --- a/tools/perf/tests/builtin-test.c
> +++ b/tools/perf/tests/builtin-test.c
> @@ -42,6 +42,8 @@
>  static bool dont_fork;
>  /* Fork the tests in parallel and wait for their completion. */
>  static bool sequential;
> +/* Number of times each test is run. */
> +static unsigned int runs_per_test = 1;
>  const char *dso_to_test;
>  const char *test_objdump_path = "objdump";
>  
> @@ -485,7 +487,7 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
>  			len = strlen(test_description(*t, i));
>  			if (width < len)
>  				width = len;
> -			num_tests++;
> +			num_tests += runs_per_test;
>  		}
>  	}
>  	child_tests = calloc(num_tests, sizeof(*child_tests));
> @@ -549,16 +551,18 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
>  				continue;
>  			}
>  
> -			test_suite__for_each_test_case(*t, curr_test_case) {
> -				if (!perf_test__matches(test_description(*t, curr_test_case),
> -							curr_suite, argc, argv))
> -					continue;
> -
> -				err = start_test(*t, curr_suite, curr_test_case,
> -						 &child_tests[child_test_num++],
> -						 width, pass);
> -				if (err)
> -					goto err_out;
> +			for (unsigned int run = 0; run < runs_per_test; run++) {
> +				test_suite__for_each_test_case(*t, curr_test_case) {
> +					if (!perf_test__matches(test_description(*t, curr_test_case),
> +								curr_suite, argc, argv))
> +						continue;
> +
> +					err = start_test(*t, curr_suite, curr_test_case,
> +							 &child_tests[child_test_num++],
> +							 width, pass);
> +					if (err)
> +						goto err_out;
> +				}
>  			}
>  		}
>  		if (!sequential) {
> @@ -698,6 +702,8 @@ int cmd_test(int argc, const char **argv)
>  		    "Do not fork for testcase"),
>  	OPT_BOOLEAN('S', "sequential", &sequential,
>  		    "Run the tests one after another rather than in parallel"),
> +	OPT_UINTEGER('r', "runs-per-test", &runs_per_test,
> +		     "Run each test the given number of times, default 1"),
>  	OPT_STRING('w', "workload", &workload, "work", "workload to run for testing, use '--list-workloads' to list the available ones."),
>  	OPT_BOOLEAN(0, "list-workloads", &list_workloads, "List the available builtin workloads to use with -w/--workload"),
>  	OPT_STRING(0, "dso", &dso_to_test, "dso", "dso to test"),
> -- 
> 2.47.1.613.gc27f4b7a9f-goog
>