kunit: add support for kunit_suites that reference init code

Add support for a new kind of kunit_suite registration macro called
kunit_test_init_section_suite(); this new registration macro allows the
registration of kunit_suites that reference functions marked __init and
data marked __initdata.
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Martin Fernandez <martin.fernandez@eclypsium.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

include/kunit/test.h

@@ -308,6 +308,34 @@ static inline int kunit_run_all_tests(void)
 
 #define kunit_test_suite(suite)	kunit_test_suites(&suite)
 
+/**
+ * kunit_test_init_section_suites() - used to register one or more &struct
+ *				      kunit_suite containing init functions or
+ *				      init data.
+ *
+ * @__suites: a statically allocated list of &struct kunit_suite.
+ *
+ * This functions identically as &kunit_test_suites() except that it suppresses
+ * modpost warnings for referencing functions marked __init or data marked
+ * __initdata; this is OK because currently KUnit only runs tests upon boot
+ * during the init phase or upon loading a module during the init phase.
+ *
+ * NOTE TO KUNIT DEVS: If we ever allow KUnit tests to be run after boot, these
+ * tests must be excluded.
+ *
+ * The only thing this macro does that's different from kunit_test_suites is
+ * that it suffixes the array and suite declarations it makes with _probe;
+ * modpost suppresses warnings about referencing init data for symbols named in
+ * this manner.
+ */
+#define kunit_test_init_section_suites(__suites...)			\
+	__kunit_test_suites(CONCATENATE(__UNIQUE_ID(array), _probe),	\
+			    CONCATENATE(__UNIQUE_ID(suites), _probe),	\
+			    ##__suites)
+
+#define kunit_test_init_section_suite(suite)	\
+	kunit_test_init_section_suites(&suite)
+
 #define kunit_suite_for_each_test_case(suite, test_case)		\
 	for (test_case = suite->test_cases; test_case->run_case; test_case++)