On Mon, Aug 26, 2024 at 08:38:21PM +0530, Devarsh Thakkar wrote: > Add tests for round_closest_up/down and roundclosest macros which round > to nearest multiple of specified argument. These are tested with kunit > tool as shared here [1] : The tests here don't seem to be well targeted at the actual edge cases where incrementing or decremting the dividend by 1 is expected to change the result, or when round_closest_up() and round_closest_down() are expected to differ. There's also no coverage of: * negative inputs * types other than int * inputs close to type limits (I've highlighted a few specific issues below, though there seems to be a more general lack of coverage here.) > > Link: https://gist.github.com/devarsht/3f9042825be3da4e133b8f4eda067876 [1] > Signed-off-by: Devarsh Thakkar <devarsht@xxxxxx> > Acked-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> > --- > V2: No change > --- > lib/math/math_kunit.c | 35 +++++++++++++++++++++++++++++++++++ > 1 file changed, 35 insertions(+) > > diff --git a/lib/math/math_kunit.c b/lib/math/math_kunit.c > index be27f2afb8e4..05022f010be6 100644 > --- a/lib/math/math_kunit.c > +++ b/lib/math/math_kunit.c > @@ -70,6 +70,26 @@ static void round_down_test(struct kunit *test) > KUNIT_EXPECT_EQ(test, round_down((1 << 30) - 1, 1 << 29), 1 << 29); > } > > +static void round_closest_up_test(struct kunit *test) > +{ > + KUNIT_EXPECT_EQ(test, round_closest_up(17, 4), 16); > + KUNIT_EXPECT_EQ(test, round_closest_up(15, 4), 16); > + KUNIT_EXPECT_EQ(test, round_closest_up(14, 4), 16); > + KUNIT_EXPECT_EQ(test, round_closest_up((1 << 30) - 1, 1 << 30), 1 << 30); > + KUNIT_EXPECT_EQ(test, round_closest_up((1 << 30) + 1, 1 << 30), 1 << 30); These miss the edge case where the result is expected to change; could we also check: round_closest_up(1 << 29, 1 << 30) > + KUNIT_EXPECT_EQ(test, round_closest_up((1 << 30) - 1, 2), 1 << 30); > +} > + > +static void round_closest_down_test(struct kunit *test) > +{ > + KUNIT_EXPECT_EQ(test, round_closest_down(17, 4), 16); > + KUNIT_EXPECT_EQ(test, round_closest_down(15, 4), 16); > + KUNIT_EXPECT_EQ(test, round_closest_down(14, 4), 12); > + KUNIT_EXPECT_EQ(test, round_closest_down((1 << 30) - 1, 1 << 30), 1 << 30); > + KUNIT_EXPECT_EQ(test, round_closest_down((1 << 30) + 1, 1 << 30), 1 << 30); > + KUNIT_EXPECT_EQ(test, round_closest_down((1 << 30) - 1, 2), (1 << 30) - 2); > +} > + > /* These versions can round to numbers that aren't a power of two */ > static void roundup_test(struct kunit *test) > { > @@ -95,6 +115,18 @@ static void rounddown_test(struct kunit *test) > KUNIT_EXPECT_EQ(test, rounddown(4, 3), 3); > } > > +static void roundclosest_test(struct kunit *test) > +{ > + KUNIT_EXPECT_EQ(test, roundclosest(21, 5), 20); > + KUNIT_EXPECT_EQ(test, roundclosest(19, 5), 20); This seems to miss the edge cases (e.g., roundclosest(20 * N + 10, 20), roundclosest(20 * N +/- 9, 20) for some N. > + KUNIT_EXPECT_EQ(test, roundclosest(17, 5), 15); > + KUNIT_EXPECT_EQ(test, roundclosest((1 << 30), 3), (1 << 30) - 1); > + KUNIT_EXPECT_EQ(test, roundclosest((1 << 30) - 1, 1 << 29), 1 << 30); > + > + KUNIT_EXPECT_EQ(test, roundclosest(4, 3), 3); > + KUNIT_EXPECT_EQ(test, roundclosest(5, 3), 6); > +} > + [...] Cheers ---Dave
