1 files changed, 41 insertions, 8 deletions

diff --git a/tools/testing/selftests/cgroup/test_cpu.c b/tools/testing/selftests/cgroup/test_cpu.c
index c83f05438d7c..735a53bb222b 100644
--- a/tools/testing/selftests/cgroup/test_cpu.c
+++ b/tools/testing/selftests/cgroup/test_cpu.c
@@ -278,7 +278,7 @@ static int test_cpucg_nice(const char *root)
 		char buf[64];
 		snprintf(buf, sizeof(buf), "%d", getpid());
 		if (cg_write(cpucg, "cgroup.procs", buf))
-			goto cleanup;
+			exit(EXIT_FAILURE);
 
 		/* Try to keep niced CPU usage as constrained to hog_cpu as possible */
 		nice(1);
@@ -291,6 +291,8 @@ static int test_cpucg_nice(const char *root)
 
 		user_usec = cg_read_key_long(cpucg, "cpu.stat", "user_usec");
 		nice_usec = cg_read_key_long(cpucg, "cpu.stat", "nice_usec");
+		if (user_usec <= 0)
+			goto cleanup;
 		if (!values_close_report(nice_usec, expected_nice_usec, 1))
 			goto cleanup;
 
@@ -640,21 +642,49 @@ test_cpucg_nested_weight_underprovisioned(const char *root)
 }
 
 /*
+ * Best effort attempt to get the kernel's HZ value from the config.
+ * Return the HZ value if found otherwise return 1000 (the default) to
+ * indicate failure.
+ */
+static long
+get_config_hz(void)
+{
+	long hz = 1000;
+	FILE *f;
+	char cmd[256] = "zcat /proc/config.gz 2>/dev/null | grep '^CONFIG_HZ='";
+
+	f = popen(cmd, "r");
+
+	if (!f)
+		return hz;
+
+	if (fscanf(f, "CONFIG_HZ=%ld", &hz) == EOF)
+		goto out;
+
+out:
+	pclose(f);
+	return hz;
+}
+
+/*
  * This test creates a cgroup with some maximum value within a period, and
  * verifies that a process in the cgroup is not overscheduled.
  */
 static int test_cpucg_max(const char *root)
 {
 	int ret = KSFT_FAIL;
+	long hz = get_config_hz();
 	long quota_usec = 1000;
 	long default_period_usec = 100000; /* cpu.max's default period */
 	long duration_seconds = 1;
 
-	long duration_usec = duration_seconds * USEC_PER_SEC;
+	long duration_usec;
 	long usage_usec, n_periods, remainder_usec, expected_usage_usec;
 	char *cpucg;
 	char quota_buf[32];
 
+	duration_usec = duration_seconds * USEC_PER_SEC * 1000 / hz;
+
 	snprintf(quota_buf, sizeof(quota_buf), "%ld", quota_usec);
 
 	cpucg = cg_name(root, "cpucg_test");
@@ -670,8 +700,8 @@ static int test_cpucg_max(const char *root)
 	struct cpu_hog_func_param param = {
 		.nprocs = 1,
 		.ts = {
-			.tv_sec = duration_seconds,
-			.tv_nsec = 0,
+			.tv_sec = duration_usec / USEC_PER_SEC,
+			.tv_nsec = duration_usec % USEC_PER_SEC * NSEC_PER_USEC,
 		},
 		.clock_type = CPU_HOG_CLOCK_WALL,
 	};
@@ -710,15 +740,18 @@ cleanup:
 static int test_cpucg_max_nested(const char *root)
 {
 	int ret = KSFT_FAIL;
+	long hz = get_config_hz();
 	long quota_usec = 1000;
 	long default_period_usec = 100000; /* cpu.max's default period */
 	long duration_seconds = 1;
 
-	long duration_usec = duration_seconds * USEC_PER_SEC;
+	long duration_usec;
 	long usage_usec, n_periods, remainder_usec, expected_usage_usec;
 	char *parent, *child;
 	char quota_buf[32];
 
+	duration_usec = duration_seconds * USEC_PER_SEC * 1000 / hz;
+
 	snprintf(quota_buf, sizeof(quota_buf), "%ld", quota_usec);
 
 	parent = cg_name(root, "cpucg_parent");
@@ -741,8 +774,8 @@ static int test_cpucg_max_nested(const char *root)
 	struct cpu_hog_func_param param = {
 		.nprocs = 1,
 		.ts = {
-			.tv_sec = duration_seconds,
-			.tv_nsec = 0,
+			.tv_sec = duration_usec / USEC_PER_SEC,
+			.tv_nsec = duration_usec % USEC_PER_SEC * NSEC_PER_USEC,
 		},
 		.clock_type = CPU_HOG_CLOCK_WALL,
 	};
@@ -799,7 +832,6 @@ int main(int argc, char *argv[])
 	int i;
 
 	ksft_print_header();
-	ksft_set_plan(ARRAY_SIZE(tests));
 	if (cg_find_unified_root(root, sizeof(root), NULL))
 		ksft_exit_skip("cgroup v2 isn't mounted\n");
 
@@ -807,6 +839,7 @@ int main(int argc, char *argv[])
 		if (cg_write(root, "cgroup.subtree_control", "+cpu"))
 			ksft_exit_skip("Failed to set cpu controller\n");
 
+	ksft_set_plan(ARRAY_SIZE(tests));
 	for (i = 0; i < ARRAY_SIZE(tests); i++) {
 		switch (tests[i].fn(root)) {
 		case KSFT_PASS: