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[PATCH v2 5/6] lib: math_kunit: Add tests for new macros related to rounding to nearest value

Devarsh Thakkar posted 6 patches 1 year, 3 months ago
[PATCH v2 5/6] lib: math_kunit: Add tests for new macros related to rounding to nearest value
Posted by Devarsh Thakkar 1 year, 3 months ago 
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] :

Link: https://gist.github.com/devarsht/3f9042825be3da4e133b8f4eda067876 [1]
Signed-off-by: Devarsh Thakkar <devarsht@ti.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
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);
+	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);
+	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);
+}
+
 static void div_round_up_test(struct kunit *test)
 {
 	KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(0, 1), 0);
@@ -272,8 +304,11 @@ static struct kunit_case math_test_cases[] = {
 	KUNIT_CASE(int_sqrt_test),
 	KUNIT_CASE(round_up_test),
 	KUNIT_CASE(round_down_test),
+	KUNIT_CASE(round_closest_up_test),
+	KUNIT_CASE(round_closest_down_test),
 	KUNIT_CASE(roundup_test),
 	KUNIT_CASE(rounddown_test),
+	KUNIT_CASE(roundclosest_test),
 	KUNIT_CASE(div_round_up_test),
 	KUNIT_CASE(div_round_closest_test),
 	KUNIT_CASE_PARAM(gcd_test, gcd_gen_params),
-- 
2.39.1
Re: [PATCH v2 5/6] lib: math_kunit: Add tests for new macros related to rounding to nearest value
Posted by Dave Martin 1 year, 3 months ago 
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@ti.com>
> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> 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

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