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Diffstat (limited to 'lib/test_linear_ranges.c')
-rw-r--r-- | lib/test_linear_ranges.c | 220 |
1 files changed, 0 insertions, 220 deletions
diff --git a/lib/test_linear_ranges.c b/lib/test_linear_ranges.c deleted file mode 100644 index f482be00f1bc..000000000000 --- a/lib/test_linear_ranges.c +++ /dev/null @@ -1,220 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * KUnit test for the linear_ranges helper. - * - * Copyright (C) 2020, ROHM Semiconductors. - * Author: Matti Vaittinen <matti.vaittien@fi.rohmeurope.com> - */ -#include <kunit/test.h> - -#include <linux/linear_range.h> - -/* First things first. I deeply dislike unit-tests. I have seen all the hell - * breaking loose when people who think the unit tests are "the silver bullet" - * to kill bugs get to decide how a company should implement testing strategy... - * - * Believe me, it may get _really_ ridiculous. It is tempting to think that - * walking through all the possible execution branches will nail down 100% of - * bugs. This may lead to ideas about demands to get certain % of "test - * coverage" - measured as line coverage. And that is one of the worst things - * you can do. - * - * Ask people to provide line coverage and they do. I've seen clever tools - * which generate test cases to test the existing functions - and by default - * these tools expect code to be correct and just generate checks which are - * passing when ran against current code-base. Run this generator and you'll get - * tests that do not test code is correct but just verify nothing changes. - * Problem is that testing working code is pointless. And if it is not - * working, your test must not assume it is working. You won't catch any bugs - * by such tests. What you can do is to generate a huge amount of tests. - * Especially if you were are asked to proivde 100% line-coverage x_x. So what - * does these tests - which are not finding any bugs now - do? - * - * They add inertia to every future development. I think it was Terry Pratchet - * who wrote someone having same impact as thick syrup has to chronometre. - * Excessive amount of unit-tests have this effect to development. If you do - * actually find _any_ bug from code in such environment and try fixing it... - * ...chances are you also need to fix the test cases. In sunny day you fix one - * test. But I've done refactoring which resulted 500+ broken tests (which had - * really zero value other than proving to managers that we do do "quality")... - * - * After this being said - there are situations where UTs can be handy. If you - * have algorithms which take some input and should produce output - then you - * can implement few, carefully selected simple UT-cases which test this. I've - * previously used this for example for netlink and device-tree data parsing - * functions. Feed some data examples to functions and verify the output is as - * expected. I am not covering all the cases but I will see the logic should be - * working. - * - * Here we also do some minor testing. I don't want to go through all branches - * or test more or less obvious things - but I want to see the main logic is - * working. And I definitely don't want to add 500+ test cases that break when - * some simple fix is done x_x. So - let's only add few, well selected tests - * which ensure as much logic is good as possible. - */ - -/* - * Test Range 1: - * selectors: 2 3 4 5 6 - * values (5): 10 20 30 40 50 - * - * Test Range 2: - * selectors: 7 8 9 10 - * values (4): 100 150 200 250 - */ - -#define RANGE1_MIN 10 -#define RANGE1_MIN_SEL 2 -#define RANGE1_STEP 10 - -/* 2, 3, 4, 5, 6 */ -static const unsigned int range1_sels[] = { RANGE1_MIN_SEL, RANGE1_MIN_SEL + 1, - RANGE1_MIN_SEL + 2, - RANGE1_MIN_SEL + 3, - RANGE1_MIN_SEL + 4 }; -/* 10, 20, 30, 40, 50 */ -static const unsigned int range1_vals[] = { RANGE1_MIN, RANGE1_MIN + - RANGE1_STEP, - RANGE1_MIN + RANGE1_STEP * 2, - RANGE1_MIN + RANGE1_STEP * 3, - RANGE1_MIN + RANGE1_STEP * 4 }; - -#define RANGE2_MIN 100 -#define RANGE2_MIN_SEL 7 -#define RANGE2_STEP 50 - -/* 7, 8, 9, 10 */ -static const unsigned int range2_sels[] = { RANGE2_MIN_SEL, RANGE2_MIN_SEL + 1, - RANGE2_MIN_SEL + 2, - RANGE2_MIN_SEL + 3 }; -/* 100, 150, 200, 250 */ -static const unsigned int range2_vals[] = { RANGE2_MIN, RANGE2_MIN + - RANGE2_STEP, - RANGE2_MIN + RANGE2_STEP * 2, - RANGE2_MIN + RANGE2_STEP * 3 }; - -#define RANGE1_NUM_VALS (ARRAY_SIZE(range1_vals)) -#define RANGE2_NUM_VALS (ARRAY_SIZE(range2_vals)) -#define RANGE_NUM_VALS (RANGE1_NUM_VALS + RANGE2_NUM_VALS) - -#define RANGE1_MAX_SEL (RANGE1_MIN_SEL + RANGE1_NUM_VALS - 1) -#define RANGE1_MAX_VAL (range1_vals[RANGE1_NUM_VALS - 1]) - -#define RANGE2_MAX_SEL (RANGE2_MIN_SEL + RANGE2_NUM_VALS - 1) -#define RANGE2_MAX_VAL (range2_vals[RANGE2_NUM_VALS - 1]) - -#define SMALLEST_SEL RANGE1_MIN_SEL -#define SMALLEST_VAL RANGE1_MIN - -static struct linear_range testr[] = { - LINEAR_RANGE(RANGE1_MIN, RANGE1_MIN_SEL, RANGE1_MAX_SEL, RANGE1_STEP), - LINEAR_RANGE(RANGE2_MIN, RANGE2_MIN_SEL, RANGE2_MAX_SEL, RANGE2_STEP), -}; - -static void range_test_get_value(struct kunit *test) -{ - int ret, i; - unsigned int sel, val; - - for (i = 0; i < RANGE1_NUM_VALS; i++) { - sel = range1_sels[i]; - ret = linear_range_get_value_array(&testr[0], 2, sel, &val); - KUNIT_EXPECT_EQ(test, 0, ret); - KUNIT_EXPECT_EQ(test, val, range1_vals[i]); - } - for (i = 0; i < RANGE2_NUM_VALS; i++) { - sel = range2_sels[i]; - ret = linear_range_get_value_array(&testr[0], 2, sel, &val); - KUNIT_EXPECT_EQ(test, 0, ret); - KUNIT_EXPECT_EQ(test, val, range2_vals[i]); - } - ret = linear_range_get_value_array(&testr[0], 2, sel + 1, &val); - KUNIT_EXPECT_NE(test, 0, ret); -} - -static void range_test_get_selector_high(struct kunit *test) -{ - int ret, i; - unsigned int sel; - bool found; - - for (i = 0; i < RANGE1_NUM_VALS; i++) { - ret = linear_range_get_selector_high(&testr[0], range1_vals[i], - &sel, &found); - KUNIT_EXPECT_EQ(test, 0, ret); - KUNIT_EXPECT_EQ(test, sel, range1_sels[i]); - KUNIT_EXPECT_TRUE(test, found); - } - - ret = linear_range_get_selector_high(&testr[0], RANGE1_MAX_VAL + 1, - &sel, &found); - KUNIT_EXPECT_LE(test, ret, 0); - - ret = linear_range_get_selector_high(&testr[0], RANGE1_MIN - 1, - &sel, &found); - KUNIT_EXPECT_EQ(test, 0, ret); - KUNIT_EXPECT_FALSE(test, found); - KUNIT_EXPECT_EQ(test, sel, range1_sels[0]); -} - -static void range_test_get_value_amount(struct kunit *test) -{ - int ret; - - ret = linear_range_values_in_range_array(&testr[0], 2); - KUNIT_EXPECT_EQ(test, (int)RANGE_NUM_VALS, ret); -} - -static void range_test_get_selector_low(struct kunit *test) -{ - int i, ret; - unsigned int sel; - bool found; - - for (i = 0; i < RANGE1_NUM_VALS; i++) { - ret = linear_range_get_selector_low_array(&testr[0], 2, - range1_vals[i], &sel, - &found); - KUNIT_EXPECT_EQ(test, 0, ret); - KUNIT_EXPECT_EQ(test, sel, range1_sels[i]); - KUNIT_EXPECT_TRUE(test, found); - } - for (i = 0; i < RANGE2_NUM_VALS; i++) { - ret = linear_range_get_selector_low_array(&testr[0], 2, - range2_vals[i], &sel, - &found); - KUNIT_EXPECT_EQ(test, 0, ret); - KUNIT_EXPECT_EQ(test, sel, range2_sels[i]); - KUNIT_EXPECT_TRUE(test, found); - } - - /* - * Seek value greater than range max => get_selector_*_low should - * return Ok - but set found to false as value is not in range - */ - ret = linear_range_get_selector_low_array(&testr[0], 2, - range2_vals[RANGE2_NUM_VALS - 1] + 1, - &sel, &found); - - KUNIT_EXPECT_EQ(test, 0, ret); - KUNIT_EXPECT_EQ(test, sel, range2_sels[RANGE2_NUM_VALS - 1]); - KUNIT_EXPECT_FALSE(test, found); -} - -static struct kunit_case range_test_cases[] = { - KUNIT_CASE(range_test_get_value_amount), - KUNIT_CASE(range_test_get_selector_high), - KUNIT_CASE(range_test_get_selector_low), - KUNIT_CASE(range_test_get_value), - {}, -}; - -static struct kunit_suite range_test_module = { - .name = "linear-ranges-test", - .test_cases = range_test_cases, -}; - -kunit_test_suites(&range_test_module); - -MODULE_DESCRIPTION("KUnit test for the linear_ranges helper"); -MODULE_LICENSE("GPL"); |