Add a KUnit test for the kernel hashtable implementation in include/linux/hashtable.h. Note that this version does not yet test each of the rcu alternative versions of functions. Signed-off-by: Rae Moar <rmoar@xxxxxxxxxx> Reviewed-by: David Gow <davidgow@xxxxxxxxxx> --- Changes since v2: - Remove extraneous hash_init() calls when using DEFINE_HASHTABLE. - Change up the size of the hashtables in different tests. - Change formatting to group lines regarding the same hashtable_test_entry. - Use KUNIT_ASSERT_LEQ() and KUNIT_ASSERT_GEQ() instead of a few if statements. Changes since v1: - Change Kconfig.debug message to be more succinct. - Directly increment current element's visited field rather than looking up corresponding element. - Use KUNIT_ASSERT_... statements to check the keys are within range rather than using if statements. - Change hash_for_each_possible test to check buckets using a hash_for_each method instead of calculating the bucket number using hash_min. Note: The check patch script is outputting open brace errors on lines 152, 185, 239 of lib/hashtable_test.c. However, I think these errors are a mistake as the format of the braces on those lines is consistent with the Linux Kernel style guide. As David Gow commented on the last version, "This is a known issue with checkpatch and function names with "for_each" in them. It was discussed here, and we ultimately decided just to ignore the warnings: https://lore.kernel.org/all/CABVgOSmCHbGjZBjeWSbPEZbJw22SaBQnoO77xxNzN_ugAwzNiQ@xxxxxxxxxxxxxx/."; lib/Kconfig.debug | 13 ++ lib/Makefile | 1 + lib/hashtable_test.c | 317 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 331 insertions(+) create mode 100644 lib/hashtable_test.c diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 881c3f84e88a..69b1452a3eeb 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2496,6 +2496,19 @@ config LIST_KUNIT_TEST If unsure, say N. +config HASHTABLE_KUNIT_TEST + tristate "KUnit Test for Kernel Hashtable structures" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds the hashtable KUnit test suite. + It tests the basic functionality of the API defined in + include/linux/hashtable.h. 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 LINEAR_RANGES_TEST tristate "KUnit test for linear_ranges" depends on KUNIT diff --git a/lib/Makefile b/lib/Makefile index 4d9461bfea42..5f8efbe8e97f 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -369,6 +369,7 @@ obj-$(CONFIG_PLDMFW) += pldmfw/ CFLAGS_bitfield_kunit.o := $(DISABLE_STRUCTLEAK_PLUGIN) obj-$(CONFIG_BITFIELD_KUNIT) += bitfield_kunit.o obj-$(CONFIG_LIST_KUNIT_TEST) += list-test.o +obj-$(CONFIG_HASHTABLE_KUNIT_TEST) += hashtable_test.o obj-$(CONFIG_LINEAR_RANGES_TEST) += test_linear_ranges.o obj-$(CONFIG_BITS_TEST) += test_bits.o obj-$(CONFIG_CMDLINE_KUNIT_TEST) += cmdline_kunit.o diff --git a/lib/hashtable_test.c b/lib/hashtable_test.c new file mode 100644 index 000000000000..1d1b3288dee2 --- /dev/null +++ b/lib/hashtable_test.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit test for the Kernel Hashtable structures. + * + * Copyright (C) 2022, Google LLC. + * Author: Rae Moar <rmoar@xxxxxxxxxx> + */ +#include <kunit/test.h> + +#include <linux/hashtable.h> + +struct hashtable_test_entry { + int key; + int data; + struct hlist_node node; + int visited; +}; + +static void hashtable_test_hash_init(struct kunit *test) +{ + /* Test the different ways of initialising a hashtable. */ + DEFINE_HASHTABLE(hash1, 2); + DECLARE_HASHTABLE(hash2, 3); + + /* When using DECLARE_HASHTABLE, must use hash_init to + * initialize the hashtable. + */ + hash_init(hash2); + + KUNIT_EXPECT_TRUE(test, hash_empty(hash1)); + KUNIT_EXPECT_TRUE(test, hash_empty(hash2)); +} + +static void hashtable_test_hash_empty(struct kunit *test) +{ + struct hashtable_test_entry a; + DEFINE_HASHTABLE(hash, 1); + + KUNIT_EXPECT_TRUE(test, hash_empty(hash)); + + a.key = 1; + a.data = 13; + hash_add(hash, &a.node, a.key); + + /* Hashtable should no longer be empty. */ + KUNIT_EXPECT_FALSE(test, hash_empty(hash)); +} + +static void hashtable_test_hash_hashed(struct kunit *test) +{ + struct hashtable_test_entry a, b; + DEFINE_HASHTABLE(hash, 4); + + a.key = 1; + a.data = 13; + hash_add(hash, &a.node, a.key); + b.key = 1; + b.data = 2; + hash_add(hash, &b.node, b.key); + + KUNIT_EXPECT_TRUE(test, hash_hashed(&a.node)); + KUNIT_EXPECT_TRUE(test, hash_hashed(&b.node)); +} + +static void hashtable_test_hash_add(struct kunit *test) +{ + struct hashtable_test_entry a, b, *x; + int bkt; + DEFINE_HASHTABLE(hash, 3); + + a.key = 1; + a.data = 13; + a.visited = 0; + hash_add(hash, &a.node, a.key); + b.key = 2; + b.data = 10; + b.visited = 0; + hash_add(hash, &b.node, b.key); + + hash_for_each(hash, bkt, x, node) { + x->visited++; + if (x->key == a.key) + KUNIT_EXPECT_EQ(test, x->data, 13); + else if (x->key == b.key) + KUNIT_EXPECT_EQ(test, x->data, 10); + else + KUNIT_FAIL(test, "Unexpected key in hashtable."); + } + + /* Both entries should have been visited exactly once. */ + KUNIT_EXPECT_EQ(test, a.visited, 1); + KUNIT_EXPECT_EQ(test, b.visited, 1); +} + +static void hashtable_test_hash_del(struct kunit *test) +{ + struct hashtable_test_entry a, b, *x; + DEFINE_HASHTABLE(hash, 6); + + a.key = 1; + a.data = 13; + hash_add(hash, &a.node, a.key); + b.key = 2; + b.data = 10; + b.visited = 0; + hash_add(hash, &b.node, b.key); + + hash_del(&b.node); + hash_for_each_possible(hash, x, node, b.key) { + x->visited++; + KUNIT_EXPECT_NE(test, x->key, b.key); + } + + /* The deleted entry should not have been visited. */ + KUNIT_EXPECT_EQ(test, b.visited, 0); + + hash_del(&a.node); + + /* The hashtable should be empty. */ + KUNIT_EXPECT_TRUE(test, hash_empty(hash)); +} + +static void hashtable_test_hash_for_each(struct kunit *test) +{ + struct hashtable_test_entry entries[3]; + struct hashtable_test_entry *x; + int bkt, i, j, count; + DEFINE_HASHTABLE(hash, 3); + + /* Add three entries to the hashtable. */ + for (i = 0; i < 3; i++) { + entries[i].key = i; + entries[i].data = i + 10; + entries[i].visited = 0; + hash_add(hash, &entries[i].node, entries[i].key); + } + + count = 0; + hash_for_each(hash, bkt, x, node) { + x->visited += 1; + KUNIT_ASSERT_GE_MSG(test, x->key, 0, "Unexpected key in hashtable."); + KUNIT_ASSERT_LT_MSG(test, x->key, 3, "Unexpected key in hashtable."); + count++; + } + + /* Should have visited each entry exactly once. */ + KUNIT_EXPECT_EQ(test, count, 3); + for (j = 0; j < 3; j++) + KUNIT_EXPECT_EQ(test, entries[j].visited, 1); +} + +static void hashtable_test_hash_for_each_safe(struct kunit *test) +{ + struct hashtable_test_entry entries[3]; + struct hashtable_test_entry *x; + struct hlist_node *tmp; + int bkt, i, j, count; + DEFINE_HASHTABLE(hash, 3); + + /* Add three entries to the hashtable. */ + for (i = 0; i < 3; i++) { + entries[i].key = i; + entries[i].data = i + 10; + entries[i].visited = 0; + hash_add(hash, &entries[i].node, entries[i].key); + } + + count = 0; + hash_for_each_safe(hash, bkt, tmp, x, node) { + x->visited += 1; + KUNIT_ASSERT_GE_MSG(test, x->key, 0, "Unexpected key in hashtable."); + KUNIT_ASSERT_LT_MSG(test, x->key, 3, "Unexpected key in hashtable."); + count++; + + /* Delete entry during loop. */ + hash_del(&x->node); + } + + /* Should have visited each entry exactly once. */ + KUNIT_EXPECT_EQ(test, count, 3); + for (j = 0; j < 3; j++) + KUNIT_EXPECT_EQ(test, entries[j].visited, 1); +} + +static void hashtable_test_hash_for_each_possible(struct kunit *test) +{ + struct hashtable_test_entry entries[4]; + struct hashtable_test_entry *x, *y; + int buckets[2]; + int bkt, i, j, count; + DEFINE_HASHTABLE(hash, 5); + + /* Add three entries with key = 0 to the hashtable. */ + for (i = 0; i < 3; i++) { + entries[i].key = 0; + entries[i].data = i; + entries[i].visited = 0; + hash_add(hash, &entries[i].node, entries[i].key); + } + + /* Add an entry with key = 1. */ + entries[3].key = 1; + entries[3].data = 3; + entries[3].visited = 0; + hash_add(hash, &entries[3].node, entries[3].key); + + count = 0; + hash_for_each_possible(hash, x, node, 0) { + x->visited += 1; + KUNIT_ASSERT_GE_MSG(test, x->data, 0, "Unexpected data in hashtable."); + KUNIT_ASSERT_LT_MSG(test, x->data, 4, "Unexpected data in hashtable."); + count++; + } + + /* Should have visited each entry with key = 0 exactly once. */ + for (j = 0; j < 3; j++) + KUNIT_EXPECT_EQ(test, entries[j].visited, 1); + + /* Save the buckets for the different keys. */ + hash_for_each(hash, bkt, y, node) { + KUNIT_ASSERT_GE_MSG(test, y->key, 0, "Unexpected key in hashtable."); + KUNIT_ASSERT_LE_MSG(test, y->key, 1, "Unexpected key in hashtable."); + buckets[y->key] = bkt; + } + + /* If entry with key = 1 is in the same bucket as the entries with + * key = 0, check it was visited. Otherwise ensure that only three + * entries were visited. + */ + if (buckets[0] == buckets[1]) { + KUNIT_EXPECT_EQ(test, count, 4); + KUNIT_EXPECT_EQ(test, entries[3].visited, 1); + } else { + KUNIT_EXPECT_EQ(test, count, 3); + KUNIT_EXPECT_EQ(test, entries[3].visited, 0); + } +} + +static void hashtable_test_hash_for_each_possible_safe(struct kunit *test) +{ + struct hashtable_test_entry entries[4]; + struct hashtable_test_entry *x, *y; + struct hlist_node *tmp; + int buckets[2]; + int bkt, i, j, count; + DEFINE_HASHTABLE(hash, 5); + + /* Add three entries with key = 0 to the hashtable. */ + for (i = 0; i < 3; i++) { + entries[i].key = 0; + entries[i].data = i; + entries[i].visited = 0; + hash_add(hash, &entries[i].node, entries[i].key); + } + + /* Add an entry with key = 1. */ + entries[3].key = 1; + entries[3].data = 3; + entries[3].visited = 0; + hash_add(hash, &entries[3].node, entries[3].key); + + count = 0; + hash_for_each_possible_safe(hash, x, tmp, node, 0) { + x->visited += 1; + KUNIT_ASSERT_GE_MSG(test, x->data, 0, "Unexpected data in hashtable."); + KUNIT_ASSERT_LT_MSG(test, x->data, 4, "Unexpected data in hashtable."); + count++; + + /* Delete entry during loop. */ + hash_del(&x->node); + } + + /* Should have visited each entry with key = 0 exactly once. */ + for (j = 0; j < 3; j++) + KUNIT_EXPECT_EQ(test, entries[j].visited, 1); + + /* Save the buckets for the different keys. */ + hash_for_each(hash, bkt, y, node) { + KUNIT_ASSERT_GE_MSG(test, y->key, 0, "Unexpected key in hashtable."); + KUNIT_ASSERT_LE_MSG(test, y->key, 1, "Unexpected key in hashtable."); + buckets[y->key] = bkt; + } + + /* If entry with key = 1 is in the same bucket as the entries with + * key = 0, check it was visited. Otherwise ensure that only three + * entries were visited. + */ + if (buckets[0] == buckets[1]) { + KUNIT_EXPECT_EQ(test, count, 4); + KUNIT_EXPECT_EQ(test, entries[3].visited, 1); + } else { + KUNIT_EXPECT_EQ(test, count, 3); + KUNIT_EXPECT_EQ(test, entries[3].visited, 0); + } +} + +static struct kunit_case hashtable_test_cases[] = { + KUNIT_CASE(hashtable_test_hash_init), + KUNIT_CASE(hashtable_test_hash_empty), + KUNIT_CASE(hashtable_test_hash_hashed), + KUNIT_CASE(hashtable_test_hash_add), + KUNIT_CASE(hashtable_test_hash_del), + KUNIT_CASE(hashtable_test_hash_for_each), + KUNIT_CASE(hashtable_test_hash_for_each_safe), + KUNIT_CASE(hashtable_test_hash_for_each_possible), + KUNIT_CASE(hashtable_test_hash_for_each_possible_safe), + {}, +}; + +static struct kunit_suite hashtable_test_module = { + .name = "hashtable", + .test_cases = hashtable_test_cases, +}; + +kunit_test_suites(&hashtable_test_module); + +MODULE_LICENSE("GPL"); base-commit: 5835ffc27381c2d32c3f0d7b575cb3397555ab47 -- 2.39.1.456.gfc5497dd1b-goog
