Adds test suite for integer based square root function.

The test suite is designed to verify the correctness of the int_sqrt() math library function.

Signed-off-by: Luis Felipe Hernandez luis.hernandez093@gmail.com --- Changes in v2 - Add new line at the end of int_sqrt_kunit.c - Add explicit header includes for MODULE_* macros, strscpy, and ULONG_MAX

Changes in v3 - Remove unnecessary new line after Kconfig entry for INT_SQRT_KUNIT_TEST - Correct int_sqrt instances with int_sqrt() in commit message and kconfig entry desc - Fix limits.h header include path

Changes in v4 - Fix Kconfig entry: remove redundant word test

Changes in v5 - Address review feedback by Nicolas Pitre npitre@baylibre.com - Make edge case portable by not relying on arch dependent macro - Add more edge cases Changes in v6 - Address review feedback by Alan Stern stern@rowland.harvard.edu - ref: https://lore.kernel.org/all/ad95d09e-ddbe-4d43-bf22-00c2008823d8@rowland.har... - Correct recipient list - Spelling and typography fixes - sqaure -> square - remove extra white space - Add edge cases to validates boundaries around perfect square --- lib/Kconfig.debug | 15 ++++++++ lib/math/Makefile | 1 + lib/math/tests/Makefile | 1 + lib/math/tests/int_sqrt_kunit.c | 66 +++++++++++++++++++++++++++++++++ 4 files changed, 83 insertions(+) create mode 100644 lib/math/tests/int_sqrt_kunit.c

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index f3d723705879..147d9fef42e7 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -3161,6 +3161,21 @@ config INT_POW_TEST

If unsure, say N

+config INT_SQRT_KUNIT_TEST + tristate "Integer square root test" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This option enables the KUnit test suite for the int_sqrt() function, + which performs square root calculation. The test suite checks + various scenarios, including edge cases, to ensure correctness. + + Enabling this option will include tests that check various scenarios + and edge cases to ensure the accuracy and reliability of the square root + function. + + If unsure, say N + endif # RUNTIME_TESTING_MENU

config ARCH_USE_MEMTEST diff --git a/lib/math/Makefile b/lib/math/Makefile index 3ef11305f8d2..25bcb968b369 100644 --- a/lib/math/Makefile +++ b/lib/math/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_INT_POW_TEST) += tests/int_pow_kunit.o obj-$(CONFIG_TEST_DIV64) += test_div64.o obj-$(CONFIG_TEST_MULDIV64) += test_mul_u64_u64_div_u64.o obj-$(CONFIG_RATIONAL_KUNIT_TEST) += rational-test.o +obj-y += tests/ diff --git a/lib/math/tests/Makefile b/lib/math/tests/Makefile index 6a169123320a..e1a79f093b2d 100644 --- a/lib/math/tests/Makefile +++ b/lib/math/tests/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only

obj-$(CONFIG_INT_POW_TEST) += int_pow_kunit.o +obj-$(CONFIG_INT_SQRT_KUNIT_TEST) += int_sqrt_kunit.o diff --git a/lib/math/tests/int_sqrt_kunit.c b/lib/math/tests/int_sqrt_kunit.c new file mode 100644 index 000000000000..1798e1312eb7 --- /dev/null +++ b/lib/math/tests/int_sqrt_kunit.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <kunit/test.h> +#include <linux/limits.h> +#include <linux/math.h> +#include <linux/module.h> +#include <linux/string.h> + +struct test_case_params { + unsigned long x; + unsigned long expected_result; + const char *name; +}; + +static const struct test_case_params params[] = { + { 0, 0, "edge case: square root of 0" }, + { 1, 1, "perfect square: square root of 1" }, + { 2, 1, "non-perfect square: square root of 2" }, + { 3, 1, "non-perfect square: square root of 3" }, + { 4, 2, "perfect square: square root of 4" }, + { 5, 2, "non-perfect square: square root of 5" }, + { 6, 2, "non-perfect square: square root of 6" }, + { 7, 2, "non-perfect square: square root of 7" }, + { 8, 2, "non-perfect square: square root of 8" }, + { 9, 3, "perfect square: square root of 9" }, + { 15, 3, "non-perfect square: square root of 15 (N-1 from 16)" }, + { 16, 4, "perfect square: square root of 16" }, + { 17, 4, "non-perfect square: square root of 17 (N+1 from 16)" }, + { 80, 8, "non-perfect square: square root of 80 (N-1 from 81)" }, + { 81, 9, "perfect square: square root of 81" }, + { 82, 9, "non-perfect square: square root of 82 (N+1 from 81)" }, + { 255, 15, "non-perfect square: square root of 255 (N-1 from 256)" }, + { 256, 16, "perfect square: square root of 256" }, + { 257, 16, "non-perfect square: square root of 257 (N+1 from 256)" }, + { 2147483648, 46340, "large input: square root of 2147483648" }, + { 4294967295, 65535, "edge case: ULONG_MAX for 32-bit" }, +}; + +static void get_desc(const struct test_case_params *tc, char *desc) +{ + strscpy(desc, tc->name, KUNIT_PARAM_DESC_SIZE); +} + +KUNIT_ARRAY_PARAM(int_sqrt, params, get_desc); + +static void int_sqrt_test(struct kunit *test) +{ + const struct test_case_params *tc = (const struct test_case_params *)test->param_value; + + KUNIT_EXPECT_EQ(test, tc->expected_result, int_sqrt(tc->x)); +} + +static struct kunit_case math_int_sqrt_test_cases[] = { + KUNIT_CASE_PARAM(int_sqrt_test, int_sqrt_gen_params), + {} +}; + +static struct kunit_suite int_sqrt_test_suite = { + .name = "math-int_sqrt", + .test_cases = math_int_sqrt_test_cases, +}; + +kunit_test_suites(&int_sqrt_test_suite); + +MODULE_DESCRIPTION("math.int_sqrt KUnit test suite"); +MODULE_LICENSE("GPL");