diff options
Diffstat (limited to 'lib/kunit')
-rw-r--r-- | lib/kunit/Makefile | 4 | ||||
-rw-r--r-- | lib/kunit/hooks-impl.h | 31 | ||||
-rw-r--r-- | lib/kunit/hooks.c | 21 | ||||
-rw-r--r-- | lib/kunit/kunit-example-test.c | 38 | ||||
-rw-r--r-- | lib/kunit/static_stub.c | 123 | ||||
-rw-r--r-- | lib/kunit/test.c | 15 |
6 files changed, 224 insertions, 8 deletions
diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile index 29aff6562b42..cb417f504996 100644 --- a/lib/kunit/Makefile +++ b/lib/kunit/Makefile @@ -2,6 +2,7 @@ obj-$(CONFIG_KUNIT) += kunit.o kunit-objs += test.o \ resource.o \ + static_stub.o \ string-stream.o \ assert.o \ try-catch.o \ @@ -11,6 +12,9 @@ ifeq ($(CONFIG_KUNIT_DEBUGFS),y) kunit-objs += debugfs.o endif +# KUnit 'hooks' are built-in even when KUnit is built as a module. +obj-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..4e71b2d0143b --- /dev/null +++ b/lib/kunit/hooks-impl.h @@ -0,0 +1,31 @@ +/* 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 <davidgow@google.com> + */ + +#ifndef _KUNIT_HOOKS_IMPL_H +#define _KUNIT_HOOKS_IMPL_H + +#include <kunit/test-bug.h> + +/* List of declarations. */ +void __printf(3, 4) __kunit_fail_current_test_impl(const char *file, + int line, + const char *fmt, ...); +void *__kunit_get_static_stub_address_impl(struct kunit *test, void *real_fn_addr); + +/* 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; + kunit_hooks.get_static_stub_address = __kunit_get_static_stub_address_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 <davidgow@google.com> + */ + + +#include <kunit/test-bug.h> + +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/kunit-example-test.c b/lib/kunit/kunit-example-test.c index 66cc4e2365ec..cd8b7e51d02b 100644 --- a/lib/kunit/kunit-example-test.c +++ b/lib/kunit/kunit-example-test.c @@ -7,6 +7,7 @@ */ #include <kunit/test.h> +#include <kunit/static_stub.h> /* * This is the most fundamental element of KUnit, the test case. A test case @@ -130,6 +131,42 @@ static void example_all_expect_macros_test(struct kunit *test) KUNIT_ASSERT_GT_MSG(test, sizeof(int), 0, "Your ints are 0-bit?!"); } +/* This is a function we'll replace with static stubs. */ +static int add_one(int i) +{ + /* This will trigger the stub if active. */ + KUNIT_STATIC_STUB_REDIRECT(add_one, i); + + return i + 1; +} + +/* This is used as a replacement for the above function. */ +static int subtract_one(int i) +{ + /* We don't need to trigger the stub from the replacement. */ + + return i - 1; +} + +/* + * This test shows the use of static stubs. + */ +static void example_static_stub_test(struct kunit *test) +{ + /* By default, function is not stubbed. */ + KUNIT_EXPECT_EQ(test, add_one(1), 2); + + /* Replace add_one() with subtract_one(). */ + kunit_activate_static_stub(test, add_one, subtract_one); + + /* add_one() is now replaced. */ + KUNIT_EXPECT_EQ(test, add_one(1), 0); + + /* Return add_one() to normal. */ + kunit_deactivate_static_stub(test, add_one); + KUNIT_EXPECT_EQ(test, add_one(1), 2); +} + /* * Here we make a list of all the test cases we want to add to the test suite * below. @@ -145,6 +182,7 @@ static struct kunit_case example_test_cases[] = { KUNIT_CASE(example_skip_test), KUNIT_CASE(example_mark_skipped_test), KUNIT_CASE(example_all_expect_macros_test), + KUNIT_CASE(example_static_stub_test), {} }; diff --git a/lib/kunit/static_stub.c b/lib/kunit/static_stub.c new file mode 100644 index 000000000000..92b2cccd5e76 --- /dev/null +++ b/lib/kunit/static_stub.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit function redirection (static stubbing) API. + * + * Copyright (C) 2022, Google LLC. + * Author: David Gow <davidgow@google.com> + */ + +#include <kunit/test.h> +#include <kunit/static_stub.h> +#include "hooks-impl.h" + + +/* Context for a static stub. This is stored in the resource data. */ +struct kunit_static_stub_ctx { + void *real_fn_addr; + void *replacement_addr; +}; + +static void __kunit_static_stub_resource_free(struct kunit_resource *res) +{ + kfree(res->data); +} + +/* Matching function for kunit_find_resource(). match_data is real_fn_addr. */ +static bool __kunit_static_stub_resource_match(struct kunit *test, + struct kunit_resource *res, + void *match_real_fn_addr) +{ + /* This pointer is only valid if res is a static stub resource. */ + struct kunit_static_stub_ctx *ctx = res->data; + + /* Make sure the resource is a static stub resource. */ + if (res->free != &__kunit_static_stub_resource_free) + return false; + + return ctx->real_fn_addr == match_real_fn_addr; +} + +/* Hook to return the address of the replacement function. */ +void *__kunit_get_static_stub_address_impl(struct kunit *test, void *real_fn_addr) +{ + struct kunit_resource *res; + struct kunit_static_stub_ctx *ctx; + void *replacement_addr; + + res = kunit_find_resource(test, + __kunit_static_stub_resource_match, + real_fn_addr); + + if (!res) + return NULL; + + ctx = res->data; + replacement_addr = ctx->replacement_addr; + kunit_put_resource(res); + return replacement_addr; +} + +void kunit_deactivate_static_stub(struct kunit *test, void *real_fn_addr) +{ + struct kunit_resource *res; + + KUNIT_ASSERT_PTR_NE_MSG(test, real_fn_addr, NULL, + "Tried to deactivate a NULL stub."); + + /* Look up the existing stub for this function. */ + res = kunit_find_resource(test, + __kunit_static_stub_resource_match, + real_fn_addr); + + /* Error out if the stub doesn't exist. */ + KUNIT_ASSERT_PTR_NE_MSG(test, res, NULL, + "Tried to deactivate a nonexistent stub."); + + /* Free the stub. We 'put' twice, as we got a reference + * from kunit_find_resource() + */ + kunit_remove_resource(test, res); + kunit_put_resource(res); +} +EXPORT_SYMBOL_GPL(kunit_deactivate_static_stub); + +/* Helper function for kunit_activate_static_stub(). The macro does + * typechecking, so use it instead. + */ +void __kunit_activate_static_stub(struct kunit *test, + void *real_fn_addr, + void *replacement_addr) +{ + struct kunit_static_stub_ctx *ctx; + struct kunit_resource *res; + + KUNIT_ASSERT_PTR_NE_MSG(test, real_fn_addr, NULL, + "Tried to activate a stub for function NULL"); + + /* If the replacement address is NULL, deactivate the stub. */ + if (!replacement_addr) { + kunit_deactivate_static_stub(test, replacement_addr); + return; + } + + /* Look up any existing stubs for this function, and replace them. */ + res = kunit_find_resource(test, + __kunit_static_stub_resource_match, + real_fn_addr); + if (res) { + ctx = res->data; + ctx->replacement_addr = replacement_addr; + + /* We got an extra reference from find_resource(), so put it. */ + kunit_put_resource(res); + } else { + ctx = kmalloc(sizeof(*ctx), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx); + ctx->real_fn_addr = real_fn_addr; + ctx->replacement_addr = replacement_addr; + res = kunit_alloc_resource(test, NULL, + &__kunit_static_stub_resource_free, + GFP_KERNEL, ctx); + } +} +EXPORT_SYMBOL_GPL(__kunit_activate_static_stub); diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 890ba5b3a981..c9e15bb60058 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -17,17 +17,14 @@ #include <linux/sched.h> #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 __printf(3, 4) __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 |