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@xxxxxxxxxxxx> --- 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 --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@xxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Test cases for util_macros.h helpers"); +MODULE_LICENSE("GPL"); -- 2.46.1