Add core facilities for defining unit tests; this provides a common way to define test cases, functions that execute code which is under test and determine whether the code under test behaves as expected; this also provides a way to group together related test cases in test suites (here we call them test_modules).
Just define test cases and how to execute them for now; setting expectations on code will be defined later.
Signed-off-by: Brendan Higgins brendanhiggins@google.com --- include/kunit/test.h | 165 ++++++++++++++++++++++++++++++++++++++++++ kunit/Kconfig | 16 +++++ kunit/Makefile | 1 + kunit/test.c | 168 +++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 350 insertions(+) create mode 100644 include/kunit/test.h create mode 100644 kunit/Kconfig create mode 100644 kunit/Makefile create mode 100644 kunit/test.c
diff --git a/include/kunit/test.h b/include/kunit/test.h new file mode 100644 index 0000000000000..23c2ebedd6dd9 --- /dev/null +++ b/include/kunit/test.h @@ -0,0 +1,165 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Base unit test (KUnit) API. + * + * Copyright (C) 2019, Google LLC. + * Author: Brendan Higgins brendanhiggins@google.com + */ + +#ifndef _KUNIT_TEST_H +#define _KUNIT_TEST_H + +#include <linux/types.h> +#include <linux/slab.h> + +struct kunit; + +/** + * struct kunit_case - represents an individual test case. + * @run_case: the function representing the actual test case. + * @name: the name of the test case. + * + * A test case is a function with the signature, ``void (*)(struct kunit *)`` + * that makes expectations (see KUNIT_EXPECT_TRUE()) about code under test. Each + * test case is associated with a &struct kunit_module and will be run after the + * module's init function and followed by the module's exit function. + * + * A test case should be static and should only be created with the KUNIT_CASE() + * macro; additionally, every array of test cases should be terminated with an + * empty test case. + * + * Example: + * + * .. code-block:: c + * + * void add_test_basic(struct kunit *test) + * { + * KUNIT_EXPECT_EQ(test, 1, add(1, 0)); + * KUNIT_EXPECT_EQ(test, 2, add(1, 1)); + * KUNIT_EXPECT_EQ(test, 0, add(-1, 1)); + * KUNIT_EXPECT_EQ(test, INT_MAX, add(0, INT_MAX)); + * KUNIT_EXPECT_EQ(test, -1, add(INT_MAX, INT_MIN)); + * } + * + * static struct kunit_case example_test_cases[] = { + * KUNIT_CASE(add_test_basic), + * {}, + * }; + * + */ +struct kunit_case { + void (*run_case)(struct kunit *test); + const char name[256]; + + /* private: internal use only. */ + bool success; +}; + +/** + * KUNIT_CASE - A helper for creating a &struct kunit_case + * @test_name: a reference to a test case function. + * + * Takes a symbol for a function representing a test case and creates a + * &struct kunit_case object from it. See the documentation for + * &struct kunit_case for an example on how to use it. + */ +#define KUNIT_CASE(test_name) { .run_case = test_name, .name = #test_name } + +/** + * struct kunit_module - describes a related collection of &struct kunit_case s. + * @name: the name of the test. Purely informational. + * @init: called before every test case. + * @exit: called after every test case. + * @test_cases: a null terminated array of test cases. + * + * A kunit_module is a collection of related &struct kunit_case s, such that + * @init is called before every test case and @exit is called after every test + * case, similar to the notion of a *test fixture* or a *test class* in other + * unit testing frameworks like JUnit or Googletest. + * + * Every &struct kunit_case must be associated with a kunit_module for KUnit to + * run it. + */ +struct kunit_module { + const char name[256]; + int (*init)(struct kunit *test); + void (*exit)(struct kunit *test); + struct kunit_case *test_cases; +}; + +/** + * struct kunit - represents a running instance of a test. + * @priv: for user to store arbitrary data. Commonly used to pass data created + * in the init function (see &struct kunit_module). + * + * Used to store information about the current context under which the test is + * running. Most of this data is private and should only be accessed indirectly + * via public functions; the one exception is @priv which can be used by the + * test writer to store arbitrary data. + */ +struct kunit { + void *priv; + + /* private: internal use only. */ + const char *name; /* Read only after initialization! */ + spinlock_t lock; /* Gaurds all mutable test state. */ + bool success; /* Protected by lock. */ + void (*vprintk)(const struct kunit *test, + const char *level, + struct va_format *vaf); +}; + +int kunit_init_test(struct kunit *test, const char *name); + +int kunit_run_tests(struct kunit_module *module); + +/** + * module_test() - used to register a &struct kunit_module with KUnit. + * @module: a statically allocated &struct kunit_module. + * + * Registers @module with the test framework. See &struct kunit_module for more + * information. + */ +#define module_test(module) \ + static int module_kunit_init##module(void) \ + { \ + return kunit_run_tests(&module); \ + } \ + late_initcall(module_kunit_init##module) + +void __printf(3, 4) kunit_printk(const char *level, + const struct kunit *test, + const char *fmt, ...); + +/** + * kunit_info() - Prints an INFO level message associated with the current test. + * @test: The test context object. + * @fmt: A printk() style format string. + * + * Prints an info level message associated with the test module being run. Takes + * a variable number of format parameters just like printk(). + */ +#define kunit_info(test, fmt, ...) \ + kunit_printk(KERN_INFO, test, fmt, ##__VA_ARGS__) + +/** + * kunit_warn() - Prints a WARN level message associated with the current test. + * @test: The test context object. + * @fmt: A printk() style format string. + * + * See kunit_info(). + */ +#define kunit_warn(test, fmt, ...) \ + kunit_printk(KERN_WARNING, test, fmt, ##__VA_ARGS__) + +/** + * kunit_err() - Prints an ERROR level message associated with the current test. + * @test: The test context object. + * @fmt: A printk() style format string. + * + * See kunit_info(). + */ +#define kunit_err(test, fmt, ...) \ + kunit_printk(KERN_ERR, test, fmt, ##__VA_ARGS__) + +#endif /* _KUNIT_TEST_H */ diff --git a/kunit/Kconfig b/kunit/Kconfig new file mode 100644 index 0000000000000..64480092b2c24 --- /dev/null +++ b/kunit/Kconfig @@ -0,0 +1,16 @@ +# +# KUnit base configuration +# + +menu "KUnit support" + +config KUNIT + bool "Enable support for unit tests (KUnit)" + help + Enables support for kernel unit tests (KUnit), a lightweight unit + testing and mocking framework for the Linux kernel. These tests are + able to be run locally on a developer's workstation without a VM or + special hardware. For more information, please see + Documentation/kunit/ + +endmenu diff --git a/kunit/Makefile b/kunit/Makefile new file mode 100644 index 0000000000000..5efdc4dea2c08 --- /dev/null +++ b/kunit/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_KUNIT) += test.o diff --git a/kunit/test.c b/kunit/test.c new file mode 100644 index 0000000000000..5bf97e2935579 --- /dev/null +++ b/kunit/test.c @@ -0,0 +1,168 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Base unit test (KUnit) API. + * + * Copyright (C) 2019, Google LLC. + * Author: Brendan Higgins brendanhiggins@google.com + */ + +#include <linux/sched.h> +#include <linux/sched/debug.h> +#include <os.h> +#include <kunit/test.h> + +static bool kunit_get_success(struct kunit *test) +{ + unsigned long flags; + bool success; + + spin_lock_irqsave(&test->lock, flags); + success = test->success; + spin_unlock_irqrestore(&test->lock, flags); + + return success; +} + +static void kunit_set_success(struct kunit *test, bool success) +{ + unsigned long flags; + + spin_lock_irqsave(&test->lock, flags); + test->success = success; + spin_unlock_irqrestore(&test->lock, flags); +} + +static int kunit_vprintk_emit(const struct kunit *test, + int level, + const char *fmt, + va_list args) +{ + return vprintk_emit(0, level, NULL, 0, fmt, args); +} + +static int kunit_printk_emit(const struct kunit *test, + int level, + const char *fmt, ...) +{ + va_list args; + int ret; + + va_start(args, fmt); + ret = kunit_vprintk_emit(test, level, fmt, args); + va_end(args); + + return ret; +} + +static void kunit_vprintk(const struct kunit *test, + const char *level, + struct va_format *vaf) +{ + kunit_printk_emit(test, + level[1] - '0', + "kunit %s: %pV", test->name, vaf); +} + +int kunit_init_test(struct kunit *test, const char *name) +{ + spin_lock_init(&test->lock); + test->name = name; + test->vprintk = kunit_vprintk; + + return 0; +} + +/* + * Initializes and runs test case. Does not clean up or do post validations. + */ +static void kunit_run_case_internal(struct kunit *test, + struct kunit_module *module, + struct kunit_case *test_case) +{ + int ret; + + if (module->init) { + ret = module->init(test); + if (ret) { + kunit_err(test, "failed to initialize: %d\n", ret); + kunit_set_success(test, false); + return; + } + } + + test_case->run_case(test); +} + +/* + * Performs post validations and cleanup after a test case was run. + * XXX: Should ONLY BE CALLED AFTER kunit_run_case_internal! + */ +static void kunit_run_case_cleanup(struct kunit *test, + struct kunit_module *module, + struct kunit_case *test_case) +{ + if (module->exit) + module->exit(test); +} + +/* + * Performs all logic to run a test case. + */ +static bool kunit_run_case(struct kunit *test, + struct kunit_module *module, + struct kunit_case *test_case) +{ + kunit_set_success(test, true); + + kunit_run_case_internal(test, module, test_case); + kunit_run_case_cleanup(test, module, test_case); + + return kunit_get_success(test); +} + +int kunit_run_tests(struct kunit_module *module) +{ + bool all_passed = true, success; + struct kunit_case *test_case; + struct kunit test; + int ret; + + ret = kunit_init_test(&test, module->name); + if (ret) + return ret; + + for (test_case = module->test_cases; test_case->run_case; test_case++) { + success = kunit_run_case(&test, module, test_case); + if (!success) + all_passed = false; + + kunit_info(&test, + "%s %s\n", + test_case->name, + success ? "passed" : "failed"); + } + + if (all_passed) + kunit_info(&test, "all tests passed\n"); + else + kunit_info(&test, "one or more tests failed\n"); + + return 0; +} + +void kunit_printk(const char *level, + const struct kunit *test, + const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + test->vprintk(test, level, &vaf); + + va_end(args); +}