Commit 4d557cb4 authored by Diego Vieira's avatar Diego Vieira Committed by Kees Cook
Browse files

lib/tests/kfifo_kunit.c: add tests for the kfifo structure 

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 doubly
linked list in lib/tests/list-test.c (previously at lib/list-test.c) [1].

Note that this patch depends on the patch that moves the KUnit tests on
lib/ into lib/tests/ [2].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/lib/list-test.c?h=v6.11-rc6
[2] https://lore.kernel.org/all/20240720181025.work.002-kees@kernel.org/



Signed-off-by: default avatarDiego Vieira <diego.daniel.professional@gmail.com>
Reviewed-by: default avatarDavid Gow <davidgow@google.com>
Reviewed-by: default avatarRae Moar <rmoar@google.com>
Link: https://lore.kernel.org/r/20241202075545.3648096-5-davidgow@google.com


Signed-off-by: default avatarKees Cook <kees@kernel.org>
parent db6fe4d6

lib/Kconfig.debug

+14 −0
Original line number Diff line number Diff line
@@ -2691,6 +2691,20 @@ 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

lib/tests/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ obj-$(CONFIG_TEST_IOV_ITER) += kunit_iov_iter.o 
obj-$(CONFIG_IS_SIGNED_TYPE_KUNIT_TEST) += is_signed_type_kunit.o

obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o

obj-$(CONFIG_LIST_KUNIT_TEST) += list-test.o

obj-$(CONFIG_KFIFO_KUNIT_TEST) += kfifo_kunit.o

obj-$(CONFIG_TEST_LIST_SORT) += test_list_sort.o

obj-$(CONFIG_LINEAR_RANGES_TEST) += test_linear_ranges.o

obj-$(CONFIG_MEMCPY_KUNIT_TEST) += memcpy_kunit.o

lib/tests/kfifo_kunit.c

0 → 100644
+224 −0
Original line number Diff line number Diff line 
// 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");

MODULE_AUTHOR("Diego Vieira <diego.daniel.professional@gmail.com>");

MODULE_DESCRIPTION("KUnit test for the kernel FIFO");