From: Trent Piepho <tpiepho@xxxxxxxxx> Subject: lib/math/rational: add Kunit test cases Adds a number of test cases that cover a range of possible code paths. [akpm@xxxxxxxxxxxxxxxxxxxx: remove non-ascii characters, fix whitespace] [colin.king@xxxxxxxxxxxxx: fix spelling mistake "demominator" -> "denominator"] Link: https://lkml.kernel.org/r/20210526085049.6393-1-colin.king@xxxxxxxxxxxxx Link: https://lkml.kernel.org/r/20210525144250.214670-2-tpiepho@xxxxxxxxx Signed-off-by: Trent Piepho <tpiepho@xxxxxxxxx> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Cc: Daniel Latypov <dlatypov@xxxxxxxxxx> Cc: Oskar Schirmer <oskar@xxxxxxxxx> Cc: Yiyuan Guo <yguoaz@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/Kconfig.debug | 12 +++++++ lib/math/Makefile | 1 lib/math/rational-test.c | 56 +++++++++++++++++++++++++++++++++++++ 3 files changed, 69 insertions(+) --- a/lib/Kconfig.debug~lib-math-rational-add-kunit-test-cases +++ a/lib/Kconfig.debug @@ -2444,6 +2444,18 @@ config SLUB_KUNIT_TEST If unsure, say N. +config RATIONAL_KUNIT_TEST + tristate "KUnit test for rational.c" if !KUNIT_ALL_TESTS + depends on KUNIT + select RATIONAL + default KUNIT_ALL_TESTS + help + This builds the rational math unit test. + 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 TEST_UDELAY tristate "udelay test driver" help --- a/lib/math/Makefile~lib-math-rational-add-kunit-test-cases +++ a/lib/math/Makefile @@ -6,3 +6,4 @@ obj-$(CONFIG_PRIME_NUMBERS) += prime_num obj-$(CONFIG_RATIONAL) += rational.o obj-$(CONFIG_TEST_DIV64) += test_div64.o +obj-$(CONFIG_RATIONAL_KUNIT_TEST) += rational-test.o --- /dev/null +++ a/lib/math/rational-test.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <kunit/test.h> + +#include <linux/rational.h> + +struct rational_test_param { + unsigned long num, den; + unsigned long max_num, max_den; + unsigned long exp_num, exp_den; + + const char *name; +}; + +static const struct rational_test_param test_parameters[] = { + { 1230, 10, 100, 20, 100, 1, "Exceeds bounds, semi-convergent term > 1/2 last term" }, + { 34567,100, 120, 20, 120, 1, "Exceeds bounds, semi-convergent term < 1/2 last term" }, + { 1, 30, 100, 10, 0, 1, "Closest to zero" }, + { 1, 19, 100, 10, 1, 10, "Closest to smallest non-zero" }, + { 27,32, 16, 16, 11, 13, "Use convergent" }, + { 1155, 7735, 255, 255, 33, 221, "Exact answer" }, + { 87, 32, 70, 32, 68, 25, "Semiconvergent, numerator limit" }, + { 14533, 4626, 15000, 2400, 7433, 2366, "Semiconvergent, denominator limit" }, +}; + +static void get_desc(const struct rational_test_param *param, char *desc) +{ + strscpy(desc, param->name, KUNIT_PARAM_DESC_SIZE); +} + +/* Creates function rational_gen_params */ +KUNIT_ARRAY_PARAM(rational, test_parameters, get_desc); + +static void rational_test(struct kunit *test) +{ + const struct rational_test_param *param = (const struct rational_test_param *)test->param_value; + unsigned long n = 0, d = 0; + + rational_best_approximation(param->num, param->den, param->max_num, param->max_den, &n, &d); + KUNIT_EXPECT_EQ(test, n, param->exp_num); + KUNIT_EXPECT_EQ(test, d, param->exp_den); +} + +static struct kunit_case rational_test_cases[] = { + KUNIT_CASE_PARAM(rational_test, rational_gen_params), + {} +}; + +static struct kunit_suite rational_test_suite = { + .name = "rational", + .test_cases = rational_test_cases, +}; + +kunit_test_suites(&rational_test_suite); + +MODULE_LICENSE("GPL v2"); _