diff mbox series

[2/2] lib: util_macros_kunit: add kunit test for util_macros.h

Message ID 20241031063707.795842-2-aardelean@baylibre.com (mailing list archive)
State Changes Requested
Headers show
Series [1/2] util_macros.h: fix/rework find_closest() macros | expand

Commit Message

Alexandru Ardelean Oct. 31, 2024, 6:37 a.m. UTC 
A bug was found in the find_closest() (find_closest_descending() is also
affected after some testing), where for certain values with small
progressions of 1, 2 & 3, the rounding (done by averaging 2 values) causes
an incorrect index to be returned.

The bug is described in more detail in the commit which fixes the bug.
This commit adds a kunit test to validate that the fix works correctly.

Signed-off-by: Alexandru Ardelean <aardelean@baylibre.com>
---
 lib/Kconfig.debug       |  17 ++++
 lib/Makefile            |   1 +
 lib/util_macros_kunit.c | 168 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 186 insertions(+)
 create mode 100644 lib/util_macros_kunit.c
diff mbox series

Patch

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 7312ae7c3cc5..caf10cf2084c 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2629,6 +2629,23 @@  config CHECKSUM_KUNIT
 
 	  If unsure, say N.
 
+config UTIL_MACROS_KUNIT
+	tristate "KUnit test util_macros.h functions at runtime" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  Enable this option to test the util_macros.h function at boot.
+
+	  KUnit tests run during boot and output the results to the debug log
+	  in TAP format (http://testanything.org/). Only useful for kernel devs
+	  running the KUnit test harness, and not intended for inclusion into a
+	  production build.
+
+	  For more information on KUnit and unit tests in general please refer
+	  to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+	  If unsure, say N.
+
 config HASH_KUNIT_TEST
 	tristate "KUnit Test for integer hash functions" if !KUNIT_ALL_TESTS
 	depends on KUNIT
diff --git a/lib/Makefile b/lib/Makefile
index 773adf88af41..444fe05caed9 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -370,6 +370,7 @@  obj-$(CONFIG_PLDMFW) += pldmfw/
 CFLAGS_bitfield_kunit.o := $(DISABLE_STRUCTLEAK_PLUGIN)
 obj-$(CONFIG_BITFIELD_KUNIT) += bitfield_kunit.o
 obj-$(CONFIG_CHECKSUM_KUNIT) += checksum_kunit.o
+obj-$(CONFIG_UTIL_MACROS_KUNIT) += util_macros_kunit.o
 obj-$(CONFIG_LIST_KUNIT_TEST) += list-test.o
 obj-$(CONFIG_HASHTABLE_KUNIT_TEST) += hashtable_test.o
 obj-$(CONFIG_LINEAR_RANGES_TEST) += test_linear_ranges.o
diff --git a/lib/util_macros_kunit.c b/lib/util_macros_kunit.c
new file mode 100644
index 000000000000..33ff8b526410
--- /dev/null
+++ b/lib/util_macros_kunit.c
@@ -0,0 +1,168 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Test cases for bitfield helpers.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <kunit/test.h>
+#include <linux/util_macros.h>
+
+#define FIND_CLOSEST_RANGE_CHECK(val_from, val_to, array, exp_idx)	\
+{									\
+	int i;								\
+	for (i = val_from; i <= val_to; i++) {				\
+		int found = find_closest(i, array, ARRAY_SIZE(array));	\
+		KUNIT_ASSERT_EQ(ctx, exp_idx, found);			\
+	}								\
+}
+
+static void test_find_closest(struct kunit *ctx)
+{
+	/* This will test a few arrays that are found in drivers */
+	static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
+	static const unsigned int ad7616_oversampling_avail[] = {
+		1, 2, 4, 8, 16, 32, 64, 128,
+	};
+	static u32 wd_timeout_table[] = { 2, 4, 6, 8, 16, 32, 48, 64 };
+	static int array_prog3a[] = { 1, 4, 7, 10 };
+	static int array_prog3b[] = { 2, 5, 8, 11 };
+	static int array_prog4a[] = { 1, 5, 9, 13 };
+	static int array_prog4b[] = { 2, 6, 10, 14 };
+
+	FIND_CLOSEST_RANGE_CHECK(-10, 2, ina226_avg_tab, 0);
+	FIND_CLOSEST_RANGE_CHECK(3, 10, ina226_avg_tab, 1);
+	FIND_CLOSEST_RANGE_CHECK(11, 40, ina226_avg_tab, 2);
+	FIND_CLOSEST_RANGE_CHECK(41, 96, ina226_avg_tab, 3);
+	FIND_CLOSEST_RANGE_CHECK(97, 192, ina226_avg_tab, 4);
+	FIND_CLOSEST_RANGE_CHECK(193, 384, ina226_avg_tab, 5);
+	FIND_CLOSEST_RANGE_CHECK(385, 768, ina226_avg_tab, 6);
+	FIND_CLOSEST_RANGE_CHECK(769, 2048, ina226_avg_tab, 7);
+
+	/* The array that found the bug that caused this kunit to exist */
+	FIND_CLOSEST_RANGE_CHECK(-10, 1, ad7616_oversampling_avail, 0);
+	FIND_CLOSEST_RANGE_CHECK(2, 3, ad7616_oversampling_avail, 1);
+	FIND_CLOSEST_RANGE_CHECK(4, 6, ad7616_oversampling_avail, 2);
+	FIND_CLOSEST_RANGE_CHECK(7, 12, ad7616_oversampling_avail, 3);
+	FIND_CLOSEST_RANGE_CHECK(13, 24, ad7616_oversampling_avail, 4);
+	FIND_CLOSEST_RANGE_CHECK(25, 48, ad7616_oversampling_avail, 5);
+	FIND_CLOSEST_RANGE_CHECK(49, 96, ad7616_oversampling_avail, 6);
+	FIND_CLOSEST_RANGE_CHECK(97, 256, ad7616_oversampling_avail, 7);
+
+	FIND_CLOSEST_RANGE_CHECK(0, 3, wd_timeout_table, 0);
+	FIND_CLOSEST_RANGE_CHECK(4, 5, wd_timeout_table, 1);
+	FIND_CLOSEST_RANGE_CHECK(6, 7, wd_timeout_table, 2);
+	FIND_CLOSEST_RANGE_CHECK(8, 12, wd_timeout_table, 3);
+	FIND_CLOSEST_RANGE_CHECK(13, 24, wd_timeout_table, 4);
+	FIND_CLOSEST_RANGE_CHECK(25, 40, wd_timeout_table, 5);
+	FIND_CLOSEST_RANGE_CHECK(41, 56, wd_timeout_table, 6);
+	FIND_CLOSEST_RANGE_CHECK(57, 128, wd_timeout_table, 7);
+
+	FIND_CLOSEST_RANGE_CHECK(-1, 2, array_prog3a, 0);
+	FIND_CLOSEST_RANGE_CHECK(3, 5, array_prog3a, 1);
+	FIND_CLOSEST_RANGE_CHECK(6, 8, array_prog3a, 2);
+	FIND_CLOSEST_RANGE_CHECK(9, 20, array_prog3a, 3);
+
+	FIND_CLOSEST_RANGE_CHECK(-1, 3, array_prog3b, 0);
+	FIND_CLOSEST_RANGE_CHECK(4, 6, array_prog3b, 1);
+	FIND_CLOSEST_RANGE_CHECK(7, 9, array_prog3b, 2);
+	FIND_CLOSEST_RANGE_CHECK(10, 20, array_prog3b, 3);
+
+	FIND_CLOSEST_RANGE_CHECK(-1, 3, array_prog4a, 0);
+	FIND_CLOSEST_RANGE_CHECK(4, 7, array_prog4a, 1);
+	FIND_CLOSEST_RANGE_CHECK(8, 11, array_prog4a, 2);
+	FIND_CLOSEST_RANGE_CHECK(12, 20, array_prog4a, 3);
+
+	FIND_CLOSEST_RANGE_CHECK(-1, 4, array_prog4b, 0);
+	FIND_CLOSEST_RANGE_CHECK(5, 8, array_prog4b, 1);
+	FIND_CLOSEST_RANGE_CHECK(9, 12, array_prog4b, 2);
+	FIND_CLOSEST_RANGE_CHECK(13, 20, array_prog4b, 3);
+}
+
+#define FIND_CLOSEST_DESC_RANGE_CHECK(val_from, val_to, array, exp_idx)	\
+{									\
+	int i;								\
+	for (i = val_from; i <= val_to; i++) {				\
+		int found = find_closest_descending(i, array,		\
+						ARRAY_SIZE(array));	\
+		KUNIT_ASSERT_EQ(ctx, exp_idx, found);			\
+	}								\
+}
+
+static void test_find_closest_descending(struct kunit *ctx)
+{
+	/* Same arrays as 'test_find_closest' but reversed */
+	static const int ina226_avg_tab[] = { 1024, 512, 256, 128, 64, 16, 4, 1 };
+	static const unsigned int ad7616_oversampling_avail[] = {
+		128, 64, 32, 16, 8, 4, 2, 1
+	};
+	static u32 wd_timeout_table[] = { 64, 48, 32, 16, 8, 6, 4, 2 };
+	static int array_prog3a[] = { 10, 7, 4, 1 };
+	static int array_prog3b[] = { 11, 8, 5, 2 };
+	static int array_prog4a[] = { 13, 9, 5, 1 };
+	static int array_prog4b[] = { 14, 10, 6, 2 };
+
+	FIND_CLOSEST_DESC_RANGE_CHECK(-10, 2, ina226_avg_tab, 7);
+	FIND_CLOSEST_DESC_RANGE_CHECK(3, 10, ina226_avg_tab, 6);
+	FIND_CLOSEST_DESC_RANGE_CHECK(11, 40, ina226_avg_tab, 5);
+	FIND_CLOSEST_DESC_RANGE_CHECK(41, 96, ina226_avg_tab, 4);
+	FIND_CLOSEST_DESC_RANGE_CHECK(97, 192, ina226_avg_tab, 3);
+	FIND_CLOSEST_DESC_RANGE_CHECK(193, 384, ina226_avg_tab, 2);
+	FIND_CLOSEST_DESC_RANGE_CHECK(385, 768, ina226_avg_tab, 1);
+	FIND_CLOSEST_DESC_RANGE_CHECK(769, 2048, ina226_avg_tab, 0);
+
+	FIND_CLOSEST_DESC_RANGE_CHECK(-10, 1, ad7616_oversampling_avail, 7);
+	FIND_CLOSEST_DESC_RANGE_CHECK(2, 3, ad7616_oversampling_avail, 6);
+	FIND_CLOSEST_DESC_RANGE_CHECK(4, 6, ad7616_oversampling_avail, 5);
+	FIND_CLOSEST_DESC_RANGE_CHECK(7, 12, ad7616_oversampling_avail, 4);
+	FIND_CLOSEST_DESC_RANGE_CHECK(13, 24, ad7616_oversampling_avail, 3);
+	FIND_CLOSEST_DESC_RANGE_CHECK(25, 48, ad7616_oversampling_avail, 2);
+	FIND_CLOSEST_DESC_RANGE_CHECK(49, 96, ad7616_oversampling_avail, 1);
+	FIND_CLOSEST_DESC_RANGE_CHECK(97, 256, ad7616_oversampling_avail, 0);
+
+	FIND_CLOSEST_DESC_RANGE_CHECK(0, 3, wd_timeout_table, 7);
+	FIND_CLOSEST_DESC_RANGE_CHECK(4, 5, wd_timeout_table, 6);
+	FIND_CLOSEST_DESC_RANGE_CHECK(6, 7, wd_timeout_table, 5);
+	FIND_CLOSEST_DESC_RANGE_CHECK(8, 12, wd_timeout_table, 4);
+	FIND_CLOSEST_DESC_RANGE_CHECK(13, 24, wd_timeout_table, 3);
+	FIND_CLOSEST_DESC_RANGE_CHECK(25, 40, wd_timeout_table, 2);
+	FIND_CLOSEST_DESC_RANGE_CHECK(41, 56, wd_timeout_table, 1);
+	FIND_CLOSEST_DESC_RANGE_CHECK(57, 128, wd_timeout_table, 0);
+
+	FIND_CLOSEST_DESC_RANGE_CHECK(-1, 2, array_prog3a, 3);
+	FIND_CLOSEST_DESC_RANGE_CHECK(3, 5, array_prog3a, 2);
+	FIND_CLOSEST_DESC_RANGE_CHECK(6, 8, array_prog3a, 1);
+	FIND_CLOSEST_DESC_RANGE_CHECK(9, 20, array_prog3a, 0);
+
+	FIND_CLOSEST_DESC_RANGE_CHECK(-1, 3, array_prog3b, 3);
+	FIND_CLOSEST_DESC_RANGE_CHECK(4, 6, array_prog3b, 2);
+	FIND_CLOSEST_DESC_RANGE_CHECK(7, 9, array_prog3b, 1);
+	FIND_CLOSEST_DESC_RANGE_CHECK(10, 20, array_prog3b, 0);
+
+	FIND_CLOSEST_DESC_RANGE_CHECK(-1, 3, array_prog4a, 3);
+	FIND_CLOSEST_DESC_RANGE_CHECK(4, 7, array_prog4a, 2);
+	FIND_CLOSEST_DESC_RANGE_CHECK(8, 11, array_prog4a, 1);
+	FIND_CLOSEST_DESC_RANGE_CHECK(12, 20, array_prog4a, 0);
+
+	FIND_CLOSEST_DESC_RANGE_CHECK(-1, 4, array_prog4b, 3);
+	FIND_CLOSEST_DESC_RANGE_CHECK(5, 8, array_prog4b, 2);
+	FIND_CLOSEST_DESC_RANGE_CHECK(9, 12, array_prog4b, 1);
+	FIND_CLOSEST_DESC_RANGE_CHECK(13, 20, array_prog4b, 0);
+}
+
+static struct kunit_case __refdata util_macros_test_cases[] = {
+	KUNIT_CASE(test_find_closest),
+	KUNIT_CASE(test_find_closest_descending),
+	{}
+};
+
+static struct kunit_suite util_macros_test_suite = {
+	.name = "util_macros.h",
+	.test_cases = util_macros_test_cases,
+};
+
+kunit_test_suites(&util_macros_test_suite);
+
+MODULE_AUTHOR("Alexandru Ardelean <aardelean@baylibre.com>");
+MODULE_DESCRIPTION("Test cases for util_macros.h helpers");
+MODULE_LICENSE("GPL");