Add KUnit tests for the kfifo data structure. They test the vast majority of macros defined in the kfifo header (include/linux/kfifo.h).

These are inspired by the existing tests for the 'list' doubly linked in lib/list-test.c [1].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/lib/...

Signed-off-by: Diego Vieira diego.daniel.professional@gmail.com --- lib/Kconfig.debug | 14 +++ lib/Makefile | 1 + lib/kfifo-test.c | 222 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 237 insertions(+) create mode 100644 lib/kfifo-test.c

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 59b6765d86b8..d7a4b996d731 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2646,6 +2646,20 @@ config SYSCTL_KUNIT_TEST

If unsure, say N.

+config KFIFO_KUNIT_TEST + tristate "KUnit Test for the generic kernel FIFO implementation" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds the generic FIFO implementation KUnit test suite. + It tests that the API and basic functionality of the kfifo type + and associated macros. + + 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 LIST_KUNIT_TEST tristate "KUnit Test for Kernel Linked-list structures" if !KUNIT_ALL_TESTS depends on KUNIT diff --git a/lib/Makefile b/lib/Makefile index 3b1769045651..db8dc4cb1b47 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -370,6 +370,7 @@ obj-$(CONFIG_PLDMFW) += pldmfw/ CFLAGS_bitfield_kunit.o := $(DISABLE_STRUCTLEAK_PLUGIN) obj-$(CONFIG_BITFIELD_KUNIT) += bitfield_kunit.o obj-$(CONFIG_CHECKSUM_KUNIT) += checksum_kunit.o +obj-$(CONFIG_KFIFO_KUNIT_TEST) += kfifo-test.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 diff --git a/lib/kfifo-test.c b/lib/kfifo-test.c new file mode 100644 index 000000000000..5ea41d22b6b5 --- /dev/null +++ b/lib/kfifo-test.c @@ -0,0 +1,222 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit test for the generic kernel FIFO implementation. + * + * Copyright (C) 2024 Diego Vieira diego.daniel.professional@gmail.com + */ +#include <kunit/test.h> + +#include <linux/kfifo.h> + +#define KFIFO_SIZE 32 +#define N_ELEMENTS 5 + +static void kfifo_test_reset_should_clear_the_fifo(struct kunit *test) +{ + DEFINE_KFIFO(my_fifo, u8, KFIFO_SIZE); + + kfifo_put(&my_fifo, 1); + kfifo_put(&my_fifo, 2); + kfifo_put(&my_fifo, 3); + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), 3); + + kfifo_reset(&my_fifo); + + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), 0); + KUNIT_EXPECT_TRUE(test, kfifo_is_empty(&my_fifo)); +} + +static void kfifo_test_define_should_define_an_empty_fifo(struct kunit *test) +{ + DEFINE_KFIFO(my_fifo, u8, KFIFO_SIZE); + + KUNIT_EXPECT_TRUE(test, kfifo_initialized(&my_fifo)); + KUNIT_EXPECT_TRUE(test, kfifo_is_empty(&my_fifo)); + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), 0); +} + +static void kfifo_test_len_should_ret_n_of_stored_elements(struct kunit *test) +{ + u8 buffer1[N_ELEMENTS]; + + for (int i = 0; i < N_ELEMENTS; i++) + buffer1[i] = i + 1; + + DEFINE_KFIFO(my_fifo, u8, KFIFO_SIZE); + + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), 0); + + kfifo_in(&my_fifo, buffer1, N_ELEMENTS); + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), N_ELEMENTS); + + kfifo_in(&my_fifo, buffer1, N_ELEMENTS); + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), N_ELEMENTS * 2); + + kfifo_reset(&my_fifo); + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), 0); +} + +static void kfifo_test_put_should_insert_and_get_should_pop(struct kunit *test) +{ + u8 out_data = 0; + int processed_elements; + u8 elements[] = { 3, 5, 11 }; + + DEFINE_KFIFO(my_fifo, u8, KFIFO_SIZE); + + // If the fifo is empty, get returns 0 + processed_elements = kfifo_get(&my_fifo, &out_data); + KUNIT_EXPECT_EQ(test, processed_elements, 0); + KUNIT_EXPECT_EQ(test, out_data, 0); + + for (int i = 0; i < 3; i++) + kfifo_put(&my_fifo, elements[i]); + + for (int i = 0; i < 3; i++) { + processed_elements = kfifo_get(&my_fifo, &out_data); + KUNIT_EXPECT_EQ(test, processed_elements, 1); + KUNIT_EXPECT_EQ(test, out_data, elements[i]); + } +} + +static void kfifo_test_in_should_insert_multiple_elements(struct kunit *test) +{ + u8 in_buffer[] = { 11, 25, 65 }; + u8 out_data; + int processed_elements; + + DEFINE_KFIFO(my_fifo, u8, KFIFO_SIZE); + + kfifo_in(&my_fifo, in_buffer, 3); + + for (int i = 0; i < 3; i++) { + processed_elements = kfifo_get(&my_fifo, &out_data); + KUNIT_EXPECT_EQ(test, processed_elements, 1); + KUNIT_EXPECT_EQ(test, out_data, in_buffer[i]); + } +} + +static void kfifo_test_out_should_pop_multiple_elements(struct kunit *test) +{ + u8 in_buffer[] = { 11, 25, 65 }; + u8 out_buffer[3]; + int copied_elements; + + DEFINE_KFIFO(my_fifo, u8, KFIFO_SIZE); + + for (int i = 0; i < 3; i++) + kfifo_put(&my_fifo, in_buffer[i]); + + copied_elements = kfifo_out(&my_fifo, out_buffer, 3); + KUNIT_EXPECT_EQ(test, copied_elements, 3); + + for (int i = 0; i < 3; i++) + KUNIT_EXPECT_EQ(test, out_buffer[i], in_buffer[i]); + KUNIT_EXPECT_TRUE(test, kfifo_is_empty(&my_fifo)); +} + +static void kfifo_test_dec_init_should_define_an_empty_fifo(struct kunit *test) +{ + DECLARE_KFIFO(my_fifo, u8, KFIFO_SIZE); + + INIT_KFIFO(my_fifo); + + // my_fifo is a struct with an inplace buffer + KUNIT_EXPECT_FALSE(test, __is_kfifo_ptr(&my_fifo)); + + KUNIT_EXPECT_TRUE(test, kfifo_initialized(&my_fifo)); +} + +static void kfifo_test_define_should_equal_declare_init(struct kunit *test) +{ + // declare a variable my_fifo of type struct kfifo of u8 + DECLARE_KFIFO(my_fifo1, u8, KFIFO_SIZE); + // initialize the my_fifo variable + INIT_KFIFO(my_fifo1); + + // DEFINE_KFIFO declares the variable with the initial value + // essentially the same as calling DECLARE_KFIFO and INIT_KFIFO + DEFINE_KFIFO(my_fifo2, u8, KFIFO_SIZE); + + // my_fifo1 and my_fifo2 have the same size + KUNIT_EXPECT_EQ(test, sizeof(my_fifo1), sizeof(my_fifo2)); + KUNIT_EXPECT_EQ(test, kfifo_initialized(&my_fifo1), + kfifo_initialized(&my_fifo2)); + KUNIT_EXPECT_EQ(test, kfifo_is_empty(&my_fifo1), + kfifo_is_empty(&my_fifo2)); +} + +static void kfifo_test_alloc_should_initiliaze_a_ptr_fifo(struct kunit *test) +{ + int ret; + DECLARE_KFIFO_PTR(my_fifo, u8); + + INIT_KFIFO(my_fifo); + + // kfifo_initialized returns false signaling the buffer pointer is NULL + KUNIT_EXPECT_FALSE(test, kfifo_initialized(&my_fifo)); + + // kfifo_alloc allocates the buffer + ret = kfifo_alloc(&my_fifo, KFIFO_SIZE, GFP_KERNEL); + KUNIT_EXPECT_EQ_MSG(test, ret, 0, "Memory allocation should succeed"); + KUNIT_EXPECT_TRUE(test, kfifo_initialized(&my_fifo)); + + // kfifo_free frees the buffer + kfifo_free(&my_fifo); +} + +static void kfifo_test_peek_should_not_remove_elements(struct kunit *test) +{ + u8 out_data; + int processed_elements; + + DEFINE_KFIFO(my_fifo, u8, KFIFO_SIZE); + + // If the fifo is empty, peek returns 0 + processed_elements = kfifo_peek(&my_fifo, &out_data); + KUNIT_EXPECT_EQ(test, processed_elements, 0); + + kfifo_put(&my_fifo, 3); + kfifo_put(&my_fifo, 5); + kfifo_put(&my_fifo, 11); + + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), 3); + + processed_elements = kfifo_peek(&my_fifo, &out_data); + KUNIT_EXPECT_EQ(test, processed_elements, 1); + KUNIT_EXPECT_EQ(test, out_data, 3); + + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), 3); + + // Using peek doesn't remove the element + // so the read element and the fifo length + // remains the same + processed_elements = kfifo_peek(&my_fifo, &out_data); + KUNIT_EXPECT_EQ(test, processed_elements, 1); + KUNIT_EXPECT_EQ(test, out_data, 3); + + KUNIT_EXPECT_EQ(test, kfifo_len(&my_fifo), 3); +} + +static struct kunit_case kfifo_test_cases[] = { + KUNIT_CASE(kfifo_test_reset_should_clear_the_fifo), + KUNIT_CASE(kfifo_test_define_should_define_an_empty_fifo), + KUNIT_CASE(kfifo_test_len_should_ret_n_of_stored_elements), + KUNIT_CASE(kfifo_test_put_should_insert_and_get_should_pop), + KUNIT_CASE(kfifo_test_in_should_insert_multiple_elements), + KUNIT_CASE(kfifo_test_out_should_pop_multiple_elements), + KUNIT_CASE(kfifo_test_dec_init_should_define_an_empty_fifo), + KUNIT_CASE(kfifo_test_define_should_equal_declare_init), + KUNIT_CASE(kfifo_test_alloc_should_initiliaze_a_ptr_fifo), + KUNIT_CASE(kfifo_test_peek_should_not_remove_elements), + {}, +}; + +static struct kunit_suite kfifo_test_module = { + .name = "kfifo", + .test_cases = kfifo_test_cases, +}; + +kunit_test_suites(&kfifo_test_module); + +MODULE_LICENSE("GPL");