summaryrefslogtreecommitdiff
path: root/lib/kunit
diff options
context:
space:
mode:
Diffstat (limited to 'lib/kunit')
-rw-r--r--lib/kunit/Makefile4
-rw-r--r--lib/kunit/hooks-impl.h31
-rw-r--r--lib/kunit/hooks.c21
-rw-r--r--lib/kunit/kunit-example-test.c38
-rw-r--r--lib/kunit/static_stub.c123
-rw-r--r--lib/kunit/test.c15
6 files changed, 224 insertions, 8 deletions
diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile
index 29aff6562b42..da665cd4ea12 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.
+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..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