Add basic test coverage for files that don't require any config options: * gcd.c * lcm.c * int_sqrt.c * reciprocal_div.c (Ignored int_pow.c since it's a simple textbook algorithm.)
These tests aren't particularly interesting, but * they're chosen as easy to understand examples of how to write tests * provides a place to add tests for any new files in this dir * written so adding new test cases to cover edge cases should be easy
Signed-off-by: Daniel Latypov dlatypov@google.com --- lib/math/Kconfig | 5 ++ lib/math/Makefile | 2 + lib/math/math_test.c | 197 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 204 insertions(+) create mode 100644 lib/math/math_test.c
diff --git a/lib/math/Kconfig b/lib/math/Kconfig index f19bc9734fa7..6ba8680439c1 100644 --- a/lib/math/Kconfig +++ b/lib/math/Kconfig @@ -15,3 +15,8 @@ config PRIME_NUMBERS
config RATIONAL bool + +config MATH_KUNIT_TEST + tristate "KUnit test for lib/math" if !KUNIT_ALL_TESTS + default KUNIT_ALL_TESTS + depends on KUNIT diff --git a/lib/math/Makefile b/lib/math/Makefile index be6909e943bd..fba6fe90f50b 100644 --- a/lib/math/Makefile +++ b/lib/math/Makefile @@ -4,3 +4,5 @@ obj-y += div64.o gcd.o lcm.o int_pow.o int_sqrt.o reciprocal_div.o obj-$(CONFIG_CORDIC) += cordic.o obj-$(CONFIG_PRIME_NUMBERS) += prime_numbers.o obj-$(CONFIG_RATIONAL) += rational.o + +obj-$(CONFIG_MATH_KUNIT_TEST) += math_test.o diff --git a/lib/math/math_test.c b/lib/math/math_test.c new file mode 100644 index 000000000000..6f4681ea7c72 --- /dev/null +++ b/lib/math/math_test.c @@ -0,0 +1,197 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Simple KUnit suite for math helper funcs that are always enabled. + * + * Copyright (C) 2020, Google LLC. + * Author: Daniel Latypov dlatypov@google.com + */ + +#include <kunit/test.h> +#include <linux/gcd.h> +#include <linux/kernel.h> +#include <linux/lcm.h> +#include <linux/reciprocal_div.h> + +/* Generic test case for unsigned long inputs. */ +struct test_case { + unsigned long a, b; + unsigned long result; +}; + +static void gcd_test(struct kunit *test) +{ + const char *message_fmt = "gcd(%lu, %lu)"; + int i; + + struct test_case test_cases[] = { + { + .a = 0, .b = 1, + .result = 1, + }, + { + .a = 2, .b = 2, + .result = 2, + }, + { + .a = 2, .b = 4, + .result = 2, + }, + { + .a = 3, .b = 5, + .result = 1, + }, + { + .a = 3*9, .b = 3*5, + .result = 3, + }, + { + .a = 3*5*7, .b = 3*5*11, + .result = 15, + }, + { + .a = (1 << 21) - 1, + .b = (1 << 22) - 1, + .result = 1, + }, + }; + + for (i = 0; i < ARRAY_SIZE(test_cases); ++i) { + KUNIT_EXPECT_EQ_MSG(test, test_cases[i].result, + gcd(test_cases[i].a, test_cases[i].b), + message_fmt, test_cases[i].a, + test_cases[i].b); + + /* gcd(a,b) == gcd(b,a) */ + KUNIT_EXPECT_EQ_MSG(test, test_cases[i].result, + gcd(test_cases[i].b, test_cases[i].a), + message_fmt, test_cases[i].b, + test_cases[i].a); + } +} + +static void lcm_test(struct kunit *test) +{ + const char *message_fmt = "lcm(%lu, %lu)"; + int i; + + struct test_case test_cases[] = { + { + .a = 0, .b = 1, + .result = 0, + }, + { + .a = 1, .b = 2, + .result = 2, + }, + { + .a = 2, .b = 2, + .result = 2, + }, + { + .a = 3*5, .b = 3*7, + .result = 3*5*7, + }, + }; + + for (i = 0; i < ARRAY_SIZE(test_cases); ++i) { + KUNIT_EXPECT_EQ_MSG(test, test_cases[i].result, + lcm(test_cases[i].a, test_cases[i].b), + message_fmt, test_cases[i].a, + test_cases[i].b); + + /* lcm(a,b) == lcm(b,a) */ + KUNIT_EXPECT_EQ_MSG(test, test_cases[i].result, + lcm(test_cases[i].b, test_cases[i].a), + message_fmt, test_cases[i].b, + test_cases[i].a); + } +} + +static void int_sqrt_test(struct kunit *test) +{ + const char *message_fmt = "sqrt(%lu)"; + int i; + + struct test_case test_cases[] = { + { + .a = 0, + .result = 0, + }, + { + .a = 1, + .result = 1, + }, + { + .a = 4, + .result = 2, + }, + { + .a = 5, + .result = 2, + }, + { + .a = 8, + .result = 2, + }, + { + .a = 1UL >> 32, + .result = 1UL >> 16, + }, + }; + + for (i = 0; i < ARRAY_SIZE(test_cases); ++i) { + KUNIT_EXPECT_EQ_MSG(test, int_sqrt(test_cases[i].a), + test_cases[i].result, message_fmt, + test_cases[i].a); + } +} + +struct reciprocal_test_case { + u32 a, b; + u32 result; +}; + +static void reciprocal_div_test(struct kunit *test) +{ + int i; + struct reciprocal_value rv; + struct reciprocal_test_case test_cases[] = { + { + .a = 0, .b = 1, + .result = 0, + }, + { + .a = 42, .b = 20, + .result = 2, + }, + { + .a = (1<<16), .b = (1<<14), + .result = 1<<2, + }, + }; + + for (i = 0; i < ARRAY_SIZE(test_cases); ++i) { + rv = reciprocal_value(test_cases[i].b); + KUNIT_EXPECT_EQ_MSG(test, test_cases[i].result, + reciprocal_divide(test_cases[i].a, rv), + "reciprocal_divide(%u, %u)", + test_cases[i].a, test_cases[i].b); + } +} + +static struct kunit_case math_test_cases[] = { + KUNIT_CASE(gcd_test), + KUNIT_CASE(lcm_test), + KUNIT_CASE(int_sqrt_test), + KUNIT_CASE(reciprocal_div_test), + {} +}; + +static struct kunit_suite math_test_suite = { + .name = "lib-math", + .test_cases = math_test_cases, +}; + +kunit_test_suites(&math_test_suite); + +MODULE_LICENSE("GPL v2");
base-commit: 7cf726a59435301046250c42131554d9ccc566b8