1 files changed, 87 insertions, 0 deletions

diff --git a/lib/kunit/kunit-example-test.c b/lib/kunit/kunit-example-test.c
index 6bb5c2ef6696..798924f7cc86 100644
--- a/lib/kunit/kunit-example-test.c
+++ b/lib/kunit/kunit-example-test.c
@@ -169,6 +169,16 @@ static int subtract_one(int i)
 }
 
 /*
+ * If the function to be replaced is static within a module it is
+ * useful to export a pointer to that function instead of having
+ * to change the static function to a non-static exported function.
+ *
+ * This pointer simulates a module exporting a pointer to a static
+ * function.
+ */
+static int (* const add_one_fn_ptr)(int i) = add_one;
+
+/*
  * This test shows the use of static stubs.
  */
 static void example_static_stub_test(struct kunit *test)
@@ -187,6 +197,30 @@ static void example_static_stub_test(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, add_one(1), 2);
 }
 
+/*
+ * This test shows the use of static stubs when the function being
+ * replaced is provided as a pointer-to-function instead of the
+ * actual function. This is useful for providing access to static
+ * functions in a module by exporting a pointer to that function
+ * instead of having to change the static function to a non-static
+ * exported function.
+ */
+static void example_static_stub_using_fn_ptr_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_fn_ptr, 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_fn_ptr);
+	KUNIT_EXPECT_EQ(test, add_one(1), 2);
+}
+
 static const struct example_param {
 	int value;
 } example_params_array[] = {
@@ -222,6 +256,20 @@ static void example_params_test(struct kunit *test)
 }
 
 /*
+ * This test shows the use of test->priv.
+ */
+static void example_priv_test(struct kunit *test)
+{
+	/* unless setup in suite->init(), test->priv is NULL */
+	KUNIT_ASSERT_NULL(test, test->priv);
+
+	/* but can be used to pass arbitrary data to other functions */
+	test->priv = kunit_kzalloc(test, 1, GFP_KERNEL);
+	KUNIT_EXPECT_NOT_NULL(test, test->priv);
+	KUNIT_ASSERT_PTR_EQ(test, test->priv, kunit_get_current_test()->priv);
+}
+
+/*
  * This test should always pass. Can be used to practice filtering attributes.
  */
 static void example_slow_test(struct kunit *test)
@@ -245,6 +293,8 @@ static struct kunit_case example_test_cases[] = {
 	KUNIT_CASE(example_mark_skipped_test),
 	KUNIT_CASE(example_all_expect_macros_test),
 	KUNIT_CASE(example_static_stub_test),
+	KUNIT_CASE(example_static_stub_using_fn_ptr_test),
+	KUNIT_CASE(example_priv_test),
 	KUNIT_CASE_PARAM(example_params_test, example_gen_params),
 	KUNIT_CASE_SLOW(example_slow_test),
 	{}
@@ -287,4 +337,41 @@ static struct kunit_suite example_test_suite = {
  */
 kunit_test_suites(&example_test_suite);
 
+static int __init init_add(int x, int y)
+{
+	return (x + y);
+}
+
+/*
+ * This test should always pass. Can be used to test init suites.
+ */
+static void __init example_init_test(struct kunit *test)
+{
+	KUNIT_EXPECT_EQ(test, init_add(1, 1), 2);
+}
+
+/*
+ * The kunit_case struct cannot be marked as __initdata as this will be
+ * used in debugfs to retrieve results after test has run
+ */
+static struct kunit_case __refdata example_init_test_cases[] = {
+	KUNIT_CASE(example_init_test),
+	{}
+};
+
+/*
+ * The kunit_suite struct cannot be marked as __initdata as this will be
+ * used in debugfs to retrieve results after test has run
+ */
+static struct kunit_suite example_init_test_suite = {
+	.name = "example_init",
+	.test_cases = example_init_test_cases,
+};
+
+/*
+ * This registers the test suite and marks the suite as using init data
+ * and/or functions.
+ */
+kunit_test_init_section_suites(&example_init_test_suite);
+
 MODULE_LICENSE("GPL v2");