selftests: vDSO: enable partial vdso_test_getrandom bench

Commit Message

Christophe Leroy Sept. 4, 2024, 11:35 a.m. UTC

In order to use vdso_test_getrandom with analysis tools like 'perf' it
can be useful to perform only one kind of test, for instead only vdso.

Add an optional argument that allows telling which of the three API
you want to benchmark.

Signed-off-by: Christophe Leroy <[e-mail]>
---
 .../selftests/vDSO/vdso_test_getrandom.c      | 122 +++++++++++-------
 1 file changed, 73 insertions(+), 49 deletions(-)

Patch

diff --git a/tools/testing/selftests/vDSO/vdso_test_getrandom.c b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
index 8866b65a4605..c38210ac8dc5 100644
--- a/tools/testing/selftests/vDSO/vdso_test_getrandom.c
+++ b/tools/testing/selftests/vDSO/vdso_test_getrandom.c
@@ -46,6 +46,10 @@  static struct {
 	.lock = PTHREAD_MUTEX_INITIALIZER
 };
 
+#define VDSO_TEST_VDSO		0x1
+#define VDSO_TEST_LIBC		0x2
+#define VDSO_TEST_SYSCALL	0x4
+
 static void *vgetrandom_get_state(void)
 {
 	void *state = NULL;
@@ -173,60 +177,72 @@  static void *test_syscall_getrandom(void *ctx)
 	return NULL;
 }
 
-static void bench_single(void)
+static void bench_single(int tests)
 {
 	struct timespec start, end, diff;
 
-	clock_gettime(CLOCK_MONOTONIC, &start);
-	test_vdso_getrandom(NULL);
-	clock_gettime(CLOCK_MONOTONIC, &end);
-	timespecsub(&end, &start, &diff);
-	printf("   vdso: %u times in %lu.%09lu seconds\n", TRIALS, diff.tv_sec, diff.tv_nsec);
-
-	clock_gettime(CLOCK_MONOTONIC, &start);
-	test_libc_getrandom(NULL);
-	clock_gettime(CLOCK_MONOTONIC, &end);
-	timespecsub(&end, &start, &diff);
-	printf("   libc: %u times in %lu.%09lu seconds\n", TRIALS, diff.tv_sec, diff.tv_nsec);
-
-	clock_gettime(CLOCK_MONOTONIC, &start);
-	test_syscall_getrandom(NULL);
-	clock_gettime(CLOCK_MONOTONIC, &end);
-	timespecsub(&end, &start, &diff);
-	printf("syscall: %u times in %lu.%09lu seconds\n", TRIALS, diff.tv_sec, diff.tv_nsec);
+	if (tests & VDSO_TEST_VDSO) {
+		clock_gettime(CLOCK_MONOTONIC, &start);
+		test_vdso_getrandom(NULL);
+		clock_gettime(CLOCK_MONOTONIC, &end);
+		timespecsub(&end, &start, &diff);
+		printf("   vdso: %u times in %lu.%09lu seconds\n", TRIALS, diff.tv_sec, diff.tv_nsec);
+	}
+
+	if (tests & VDSO_TEST_LIBC) {
+		clock_gettime(CLOCK_MONOTONIC, &start);
+		test_libc_getrandom(NULL);
+		clock_gettime(CLOCK_MONOTONIC, &end);
+		timespecsub(&end, &start, &diff);
+		printf("   libc: %u times in %lu.%09lu seconds\n", TRIALS, diff.tv_sec, diff.tv_nsec);
+	}
+
+	if (tests & VDSO_TEST_SYSCALL) {
+		clock_gettime(CLOCK_MONOTONIC, &start);
+		test_syscall_getrandom(NULL);
+		clock_gettime(CLOCK_MONOTONIC, &end);
+		timespecsub(&end, &start, &diff);
+		printf("syscall: %u times in %lu.%09lu seconds\n", TRIALS, diff.tv_sec, diff.tv_nsec);
+	}
 }
 
-static void bench_multi(void)
+static void bench_multi(int tests)
 {
 	struct timespec start, end, diff;
 	pthread_t threads[THREADS];
 
-	clock_gettime(CLOCK_MONOTONIC, &start);
-	for (size_t i = 0; i < THREADS; ++i)
-		assert(pthread_create(&threads[i], NULL, test_vdso_getrandom, NULL) == 0);
-	for (size_t i = 0; i < THREADS; ++i)
-		pthread_join(threads[i], NULL);
-	clock_gettime(CLOCK_MONOTONIC, &end);
-	timespecsub(&end, &start, &diff);
-	printf("   vdso: %u x %u times in %lu.%09lu seconds\n", TRIALS, THREADS, diff.tv_sec, diff.tv_nsec);
-
-	clock_gettime(CLOCK_MONOTONIC, &start);
-	for (size_t i = 0; i < THREADS; ++i)
-		assert(pthread_create(&threads[i], NULL, test_libc_getrandom, NULL) == 0);
-	for (size_t i = 0; i < THREADS; ++i)
-		pthread_join(threads[i], NULL);
-	clock_gettime(CLOCK_MONOTONIC, &end);
-	timespecsub(&end, &start, &diff);
-	printf("   libc: %u x %u times in %lu.%09lu seconds\n", TRIALS, THREADS, diff.tv_sec, diff.tv_nsec);
-
-	clock_gettime(CLOCK_MONOTONIC, &start);
-	for (size_t i = 0; i < THREADS; ++i)
-		assert(pthread_create(&threads[i], NULL, test_syscall_getrandom, NULL) == 0);
-	for (size_t i = 0; i < THREADS; ++i)
-		pthread_join(threads[i], NULL);
-	clock_gettime(CLOCK_MONOTONIC, &end);
-	timespecsub(&end, &start, &diff);
-	printf("   syscall: %u x %u times in %lu.%09lu seconds\n", TRIALS, THREADS, diff.tv_sec, diff.tv_nsec);
+	if (tests & VDSO_TEST_VDSO) {
+		clock_gettime(CLOCK_MONOTONIC, &start);
+		for (size_t i = 0; i < THREADS; ++i)
+			assert(pthread_create(&threads[i], NULL, test_vdso_getrandom, NULL) == 0);
+		for (size_t i = 0; i < THREADS; ++i)
+			pthread_join(threads[i], NULL);
+		clock_gettime(CLOCK_MONOTONIC, &end);
+		timespecsub(&end, &start, &diff);
+		printf("   vdso: %u x %u times in %lu.%09lu seconds\n", TRIALS, THREADS, diff.tv_sec, diff.tv_nsec);
+	}
+
+	if (tests & VDSO_TEST_LIBC) {
+		clock_gettime(CLOCK_MONOTONIC, &start);
+		for (size_t i = 0; i < THREADS; ++i)
+			assert(pthread_create(&threads[i], NULL, test_libc_getrandom, NULL) == 0);
+		for (size_t i = 0; i < THREADS; ++i)
+			pthread_join(threads[i], NULL);
+		clock_gettime(CLOCK_MONOTONIC, &end);
+		timespecsub(&end, &start, &diff);
+		printf("   libc: %u x %u times in %lu.%09lu seconds\n", TRIALS, THREADS, diff.tv_sec, diff.tv_nsec);
+	}
+
+	if (tests & VDSO_TEST_SYSCALL) {
+		clock_gettime(CLOCK_MONOTONIC, &start);
+		for (size_t i = 0; i < THREADS; ++i)
+			assert(pthread_create(&threads[i], NULL, test_syscall_getrandom, NULL) == 0);
+		for (size_t i = 0; i < THREADS; ++i)
+			pthread_join(threads[i], NULL);
+		clock_gettime(CLOCK_MONOTONIC, &end);
+		timespecsub(&end, &start, &diff);
+		printf("   syscall: %u x %u times in %lu.%09lu seconds\n", TRIALS, THREADS, diff.tv_sec, diff.tv_nsec);
+	}
 }
 
 static void fill(void)
@@ -255,11 +271,13 @@  static void kselftest(void)
 
 static void usage(const char *argv0)
 {
-	fprintf(stderr, "Usage: %s [bench-single|bench-multi|fill]\n", argv0);
+	fprintf(stderr, "Usage: %s [bench-single|bench-multi|fill [vdso|libc|syscall]]\n", argv0);
 }
 
 int main(int argc, char *argv[])
 {
+	int tests = VDSO_TEST_VDSO | VDSO_TEST_LIBC | VDSO_TEST_SYSCALL;
+
 	vgetrandom_init();
 
 	if (argc == 1) {
@@ -267,14 +285,20 @@  int main(int argc, char *argv[])
 		return 0;
 	}
 
-	if (argc != 2) {
+	if (argc == 3 && !strcmp(argv[2], "vdso")) {
+		tests = VDSO_TEST_VDSO;
+	} else if (argc == 3 && !strcmp(argv[2], "libc")) {
+		tests = VDSO_TEST_LIBC;
+	} else if (argc == 3 && !strcmp(argv[2], "syscall")) {
+		tests = VDSO_TEST_SYSCALL;
+	} else if (argc != 2) {
 		usage(argv[0]);
 		return 1;
 	}
 	if (!strcmp(argv[1], "bench-single"))
-		bench_single();
+		bench_single(tests);
 	else if (!strcmp(argv[1], "bench-multi"))
-		bench_multi();
+		bench_multi(tests);
 	else if (!strcmp(argv[1], "fill"))
 		fill();
 	else {