From: Petr Mladek <pmladek@suse.com>

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 <pmladek@suse.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
 lib/tests/test_ratelimit.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/tests/test_ratelimit.c b/lib/tests/test_ratelimit.c
index 0374107f5ea89..5d6ec88546005 100644
--- a/lib/tests/test_ratelimit.c
+++ b/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);
-- 
2.40.1

On Wed,  9 Jul 2025 11:03:34 -0700 "Paul E. McKenney" <paulmck@kernel.org> wrote:

> 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 <pmladek@suse.com>
> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
> ---
>  lib/tests/test_ratelimit.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)

Patch 1 adds test_ratelimit.c and patch 2 fixes it.

Unconventional (and undesirable IMO).  Would the world end if I folded
2 into 1?

On Wed, Jul 09, 2025 at 03:44:54PM -0700, Andrew Morton wrote:
> On Wed,  9 Jul 2025 11:03:34 -0700 "Paul E. McKenney" <paulmck@kernel.org> wrote:
> 
> > 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 <pmladek@suse.com>
> > Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
> > ---
> >  lib/tests/test_ratelimit.c | 8 ++++----
> >  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> Patch 1 adds test_ratelimit.c and patch 2 fixes it.
> 
> Unconventional (and undesirable IMO).  Would the world end if I folded
> 2 into 1?

Folding them together works for me, as long as Petr is properly credited.

							Thanx, Paul