Commit 84ec093f authored by Bruno Sobreira França's avatar Bruno Sobreira França Committed by Kees Cook
Browse files

lib/math: Add int_log test suite 



This commit introduces KUnit tests for the intlog2 and intlog10
functions, which compute logarithms in base 2 and base 10, respectively.
The tests cover a range of inputs to ensure the correctness of these
functions across common and edge cases.

Signed-off-by: default avatarBruno Sobreira França <brunofrancadevsec@gmail.com>
Reviewed-by: default avatarDavid Gow <davidgow@google.com>
Reviewed-by: default avatarRae Moar <rmoar@google.com>
Link: https://lore.kernel.org/r/20241202075545.3648096-3-davidgow@google.com


Signed-off-by: default avatarKees Cook <kees@kernel.org>
parent 3e50ba8f

lib/Kconfig.debug

+11 −0
Original line number Diff line number Diff line
@@ -3197,6 +3197,17 @@ config INT_SQRT_KUNIT_TEST 


	  If unsure, say N



config INT_LOG_KUNIT_TEST

        tristate "Integer log (int_log) test" if !KUNIT_ALL_TESTS

        depends on KUNIT

        default KUNIT_ALL_TESTS

        help

          This option enables the KUnit test suite for the int_log library, which

          provides two functions to compute the integer logarithm in base 2 and

          base 10, called respectively as intlog2 and intlog10.



          If unsure, say N



endif # RUNTIME_TESTING_MENU



config ARCH_USE_MEMTEST

lib/math/tests/Makefile

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# SPDX-License-Identifier: GPL-2.0-only



obj-$(CONFIG_INT_LOG_KUNIT_TEST)	+= int_log_kunit.o

obj-$(CONFIG_INT_POW_KUNIT_TEST)	+= int_pow_kunit.o

obj-$(CONFIG_INT_SQRT_KUNIT_TEST)	+= int_sqrt_kunit.o

obj-$(CONFIG_RATIONAL_KUNIT_TEST)	+= rational_kunit.o

lib/math/tests/int_log_kunit.c

0 → 100644
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// SPDX-License-Identifier: GPL-2.0-only

#include <kunit/test.h>

#include <linux/int_log.h>



struct test_case_params {

	u32 value;

	unsigned int expected_result;

	const char *name;

};





/* The expected result takes into account the log error */

static const struct test_case_params intlog2_params[] = {

	{0, 0, "Log base 2 of 0"},

	{1, 0, "Log base 2 of 1"},

	{2, 16777216, "Log base 2 of 2"},

	{3, 26591232, "Log base 2 of 3"},

	{4, 33554432, "Log base 2 of 4"},

	{8, 50331648, "Log base 2 of 8"},

	{16, 67108864, "Log base 2 of 16"},

	{32, 83886080, "Log base 2 of 32"},

	{U32_MAX, 536870911, "Log base 2 of MAX"},

};



static const struct test_case_params intlog10_params[] = {

	{0, 0, "Log base 10 of 0"},

	{1, 0, "Log base 10 of 1"},

	{6, 13055203, "Log base 10 of 6"},

	{10, 16777225, "Log base 10 of 10"},

	{100, 33554450, "Log base 10 of 100"},

	{1000, 50331675, "Log base 10 of 1000"},

	{10000, 67108862, "Log base 10 of 10000"},

	{U32_MAX, 161614247, "Log base 10 of MAX"}

};



static void get_desc(const struct test_case_params *tc, char *desc)

{

	strscpy(desc, tc->name, KUNIT_PARAM_DESC_SIZE);

}





KUNIT_ARRAY_PARAM(intlog2, intlog2_params, get_desc);



static void intlog2_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, intlog2(tc->value));

}



KUNIT_ARRAY_PARAM(intlog10, intlog10_params, get_desc);



static void intlog10_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, intlog10(tc->value));

}



static struct kunit_case math_int_log_test_cases[] = {

	KUNIT_CASE_PARAM(intlog2_test, intlog2_gen_params),

	KUNIT_CASE_PARAM(intlog10_test, intlog10_gen_params),

	{}

};



static struct kunit_suite int_log_test_suite = {

	.name = "math-int_log",

	.test_cases =  math_int_log_test_cases,

};



kunit_test_suites(&int_log_test_suite);



MODULE_DESCRIPTION("math.int_log KUnit test suite");

MODULE_LICENSE("GPL");