lib: Make the ratelimit test more reliable

The selftest fails most of the times when running in qemu with
a kernel configured with CONFIG_HZ = 250:

>  test_ratelimit_smoke: 1 callbacks suppressed
>  # test_ratelimit_smoke: ASSERTION FAILED at lib/tests/test_ratelimit.c:28
>                    Expected ___ratelimit(&testrl, "test_ratelimit_smoke") == (false), but
>                        ___ratelimit(&testrl, "test_ratelimit_smoke") == 1 (0x1)
>                        (false) == 0 (0x0)

Try to make the test slightly more reliable by calling the problematic
ratelimit in the middle of the interval.

Signed-off-by: Petr Mladek <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>

Author: pmladek

lib/tests/test_ratelimit.c

@@ -24,19 +24,19 @@ static void test_ratelimit_smoke(struct kunit *test)
 	test_ratelimited(test, true);
 	test_ratelimited(test, false);
 
-	schedule_timeout_idle(TESTRL_INTERVAL - 40);
+	schedule_timeout_idle(TESTRL_INTERVAL / 2);
 	test_ratelimited(test, false);
 
-	schedule_timeout_idle(50);
+	schedule_timeout_idle(TESTRL_INTERVAL * 3 / 4);
 	test_ratelimited(test, true);
 
 	schedule_timeout_idle(2 * TESTRL_INTERVAL);
 	test_ratelimited(test, true);
 	test_ratelimited(test, true);
 
-	schedule_timeout_idle(TESTRL_INTERVAL - 40);
+	schedule_timeout_idle(TESTRL_INTERVAL / 2 );
 	test_ratelimited(test, true);
-	schedule_timeout_idle(50);
+	schedule_timeout_idle(TESTRL_INTERVAL * 3 / 4);
 	test_ratelimited(test, true);
 	test_ratelimited(test, true);
 	test_ratelimited(test, true);