diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst index 48f8196d5aad..9faf2b4153fc 100644 --- a/Documentation/dev-tools/kunit/usage.rst +++ b/Documentation/dev-tools/kunit/usage.rst @@ -648,10 +648,9 @@ We can do this via the ``kunit_test`` field in ``task_struct``, which we can access using the ``kunit_get_current_test()`` function in ``kunit/test-bug.h``. ``kunit_get_current_test()`` is safe to call even if KUnit is not enabled. If -KUnit is not enabled, was built as a module (``CONFIG_KUNIT=m``), or no test is -running in the current task, it will return ``NULL``. This compiles down to -either a no-op or a static key check, so will have a negligible performance -impact when no test is running. +KUnit is not enabled, or if no test is running in the current task, it will +return ``NULL``. This compiles down to either a no-op or a static key check, +so will have a negligible performance impact when no test is running. The example below uses this to implement a "mock" implementation of a function, ``foo``: @@ -726,8 +725,6 @@ structures as shown below: #endif ``kunit_fail_current_test()`` is safe to call even if KUnit is not enabled. If -KUnit is not enabled, was built as a module (``CONFIG_KUNIT=m``), or no test is -running in the current task, it will do nothing. This compiles down to either a -no-op or a static key check, so will have a negligible performance impact when -no test is running. - +KUnit is not enabled, or if no test is running in the current task, it will do +nothing. This compiles down to either a no-op or a static key check, so will +have a negligible performance impact when no test is running. diff --git a/include/kunit/test-bug.h b/include/kunit/test-bug.h index c1b2e14eab64..2b505a95b641 100644 --- a/include/kunit/test-bug.h +++ b/include/kunit/test-bug.h @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* - * KUnit API allowing dynamic analysis tools to interact with KUnit tests + * KUnit API providing hooks for non-test code to interact with tests. * * Copyright (C) 2020, Google LLC. * Author: Uriel Guajardo @@ -9,7 +9,7 @@ #ifndef _KUNIT_TEST_BUG_H #define _KUNIT_TEST_BUG_H -#if IS_BUILTIN(CONFIG_KUNIT) +#if IS_ENABLED(CONFIG_KUNIT) #include /* For static branch */ #include @@ -17,6 +17,11 @@ /* Static key if KUnit is running any tests. */ DECLARE_STATIC_KEY_FALSE(kunit_running); +/* Hooks table: a table of function pointers filled in when kunit loads */ +extern struct kunit_hooks_table { + __printf(3, 4) void (*fail_current_test)(const char*, int, const char*, ...); +} kunit_hooks; + /** * kunit_get_current_test() - Return a pointer to the currently running * KUnit test. @@ -43,33 +48,20 @@ static inline struct kunit *kunit_get_current_test(void) * kunit_fail_current_test() - If a KUnit test is running, fail it. * * If a KUnit test is running in the current task, mark that test as failed. - * - * This macro will only work if KUnit is built-in (though the tests - * themselves can be modules). Otherwise, it compiles down to nothing. */ #define kunit_fail_current_test(fmt, ...) do { \ if (static_branch_unlikely(&kunit_running)) { \ - __kunit_fail_current_test(__FILE__, __LINE__, \ + /* Guaranteed to be non-NULL when kunit_running true*/ \ + kunit_hooks.fail_current_test(__FILE__, __LINE__, \ fmt, ##__VA_ARGS__); \ } \ } while (0) - -extern __printf(3, 4) void __kunit_fail_current_test(const char *file, int line, - const char *fmt, ...); - #else static inline struct kunit *kunit_get_current_test(void) { return NULL; } -/* We define this with an empty helper function so format string warnings work */ -#define kunit_fail_current_test(fmt, ...) \ - __kunit_fail_current_test(__FILE__, __LINE__, fmt, ##__VA_ARGS__) - -static inline __printf(3, 4) void __kunit_fail_current_test(const char *file, int line, - const char *fmt, ...) -{ -} +#define kunit_fail_current_test(fmt, ...) do {} while (0) #endif diff --git a/lib/Makefile b/lib/Makefile index 4d9461bfea42..55fd04a7d0fb 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -126,6 +126,14 @@ CFLAGS_test_fpu.o += $(FPU_CFLAGS) obj-$(CONFIG_TEST_LIVEPATCH) += livepatch/ obj-$(CONFIG_KUNIT) += kunit/ +# Include the KUnit hooks unconditionally. They'll compile to nothing if +# CONFIG_KUNIT=n, otherwise will be a small table of static data (static key, +# function pointers) which need to be built-in even when KUnit is a module. +ifeq ($(CONFIG_KUNIT), m) +obj-y += kunit/hooks.o +else +obj-$(CONFIG_KUNIT) += kunit/hooks.o +endif ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile index 29aff6562b42..deeb46cc879b 100644 --- a/lib/kunit/Makefile +++ b/lib/kunit/Makefile @@ -11,6 +11,9 @@ ifeq ($(CONFIG_KUNIT_DEBUGFS),y) kunit-objs += debugfs.o endif +# KUnit 'hooks' are built-in even when KUnit is built as a module. +lib-y += hooks.o + obj-$(CONFIG_KUNIT_TEST) += kunit-test.o # string-stream-test compiles built-in only. diff --git a/lib/kunit/hooks-impl.h b/lib/kunit/hooks-impl.h new file mode 100644 index 000000000000..d911f40f76db --- /dev/null +++ b/lib/kunit/hooks-impl.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Declarations for hook implementations. + * + * These will be set as the function pointers in struct kunit_hook_table, + * found in include/kunit/test-bug.h. + * + * Copyright (C) 2023, Google LLC. + * Author: David Gow + */ + +#ifndef _KUNIT_HOOKS_IMPL_H +#define _KUNIT_HOOKS_IMPL_H + +#include + +/* List of declarations. */ +void __kunit_fail_current_test_impl(const char *file, int line, const char *fmt, ...); + +/* Code to set all of the function pointers. */ +static inline void kunit_install_hooks(void) +{ + /* Install the KUnit hook functions. */ + kunit_hooks.fail_current_test = __kunit_fail_current_test_impl; +} + +#endif /* _KUNIT_HOOKS_IMPL_H */ diff --git a/lib/kunit/hooks.c b/lib/kunit/hooks.c new file mode 100644 index 000000000000..365d98d4953c --- /dev/null +++ b/lib/kunit/hooks.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit 'Hooks' implementation. + * + * This file contains code / structures which should be built-in even when + * KUnit itself is built as a module. + * + * Copyright (C) 2022, Google LLC. + * Author: David Gow + */ + + +#include + +DEFINE_STATIC_KEY_FALSE(kunit_running); +EXPORT_SYMBOL(kunit_running); + +/* Function pointers for hooks. */ +struct kunit_hooks_table kunit_hooks; +EXPORT_SYMBOL(kunit_hooks); + diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 890ba5b3a981..51cae59d8aae 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -17,17 +17,14 @@ #include #include "debugfs.h" +#include "hooks-impl.h" #include "string-stream.h" #include "try-catch-impl.h" -DEFINE_STATIC_KEY_FALSE(kunit_running); -EXPORT_SYMBOL_GPL(kunit_running); - -#if IS_BUILTIN(CONFIG_KUNIT) /* - * Fail the current test and print an error message to the log. + * Hook to fail the current test and print an error message to the log. */ -void __kunit_fail_current_test(const char *file, int line, const char *fmt, ...) +void __kunit_fail_current_test_impl(const char *file, int line, const char *fmt, ...) { va_list args; int len; @@ -54,8 +51,6 @@ void __kunit_fail_current_test(const char *file, int line, const char *fmt, ...) kunit_err(current->kunit_test, "%s:%d: %s", file, line, buffer); kunit_kfree(current->kunit_test, buffer); } -EXPORT_SYMBOL_GPL(__kunit_fail_current_test); -#endif /* * Enable KUnit tests to run. @@ -778,6 +773,9 @@ EXPORT_SYMBOL_GPL(kunit_cleanup); static int __init kunit_init(void) { + /* Install the KUnit hook functions. */ + kunit_install_hooks(); + kunit_debugfs_init(); #ifdef CONFIG_MODULES return register_module_notifier(&kunit_mod_nb); @@ -789,6 +787,7 @@ late_initcall(kunit_init); static void __exit kunit_exit(void) { + memset(&kunit_hooks, 0, sizeof(kunit_hooks)); #ifdef CONFIG_MODULES unregister_module_notifier(&kunit_mod_nb); #endif