[PATCH v6 2/5] kunit: test: create a single centralized executor for all tests

From: Brendan Higgins
Date: Tue Aug 04 2020 - 16:48:23 EST


From: Alan Maguire <alan.maguire@xxxxxxxxxx>

Add a centralized executor to dispatch tests rather than relying on
late_initcall to schedule each test suite separately. Centralized
execution is for built-in tests only; modules will execute tests when
loaded.

Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
Co-developed-by: Iurii Zaikin <yzaikin@xxxxxxxxxx>
Signed-off-by: Iurii Zaikin <yzaikin@xxxxxxxxxx>
Co-developed-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
Signed-off-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
Reviewed-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
include/kunit/test.h | 67 +++++++++++++++++++++++++++++---------------
lib/kunit/Makefile | 3 +-
lib/kunit/executor.c | 28 ++++++++++++++++++
lib/kunit/test.c | 2 +-
4 files changed, 76 insertions(+), 24 deletions(-)
create mode 100644 lib/kunit/executor.c

diff --git a/include/kunit/test.h b/include/kunit/test.h
index 47e61e1d53370..f3e86c3953a2b 100644
--- a/include/kunit/test.h
+++ b/include/kunit/test.h
@@ -224,7 +224,7 @@ size_t kunit_suite_num_test_cases(struct kunit_suite *suite);
unsigned int kunit_test_case_num(struct kunit_suite *suite,
struct kunit_case *test_case);

-int __kunit_test_suites_init(struct kunit_suite **suites);
+int __kunit_test_suites_init(struct kunit_suite * const * const suites);

void __kunit_test_suites_exit(struct kunit_suite **suites);

@@ -237,34 +237,57 @@ void __kunit_test_suites_exit(struct kunit_suite **suites);
* Registers @suites_list with the test framework. See &struct kunit_suite for
* more information.
*
- * When builtin, KUnit tests are all run as late_initcalls; this means
- * that they cannot test anything where tests must run at a different init
- * phase. One significant restriction resulting from this is that KUnit
- * cannot reliably test anything that is initialize in the late_init phase;
- * another is that KUnit is useless to test things that need to be run in
- * an earlier init phase.
- *
- * An alternative is to build the tests as a module. Because modules
- * do not support multiple late_initcall()s, we need to initialize an
- * array of suites for a module.
- *
- * TODO(brendanhiggins@xxxxxxxxxx): Don't run all KUnit tests as
- * late_initcalls. I have some future work planned to dispatch all KUnit
- * tests from the same place, and at the very least to do so after
- * everything else is definitely initialized.
+ * If a test suite is built-in, module_init() gets translated into
+ * an initcall which we don't want as the idea is that for builtins
+ * the executor will manage execution. So ensure we do not define
+ * module_{init|exit} functions for the builtin case when registering
+ * suites via kunit_test_suites() below.
*/
-#define kunit_test_suites(suites_list...) \
- static struct kunit_suite *suites[] = {suites_list, NULL}; \
- static int kunit_test_suites_init(void) \
+#ifdef MODULE
+#define kunit_test_suites_for_module(__suites) \
+ static int __init kunit_test_suites_init(void) \
{ \
- return __kunit_test_suites_init(suites); \
+ return __kunit_test_suites_init(__suites); \
} \
- late_initcall(kunit_test_suites_init); \
+ module_init(kunit_test_suites_init); \
+ \
static void __exit kunit_test_suites_exit(void) \
{ \
- return __kunit_test_suites_exit(suites); \
+ return __kunit_test_suites_exit(__suites); \
} \
module_exit(kunit_test_suites_exit)
+#else
+#define kunit_test_suites_for_module(__suites)
+#endif /* MODULE */
+
+#define __kunit_test_suites(unique_array, unique_suites, ...) \
+ static struct kunit_suite *unique_array[] = { __VA_ARGS__, NULL }; \
+ kunit_test_suites_for_module(unique_array); \
+ static struct kunit_suite **unique_suites \
+ __used __section(.kunit_test_suites) = unique_array
+
+/**
+ * kunit_test_suites() - used to register one or more &struct kunit_suite
+ * with KUnit.
+ *
+ * @suites: a statically allocated list of &struct kunit_suite.
+ *
+ * Registers @suites with the test framework. See &struct kunit_suite for
+ * more information.
+ *
+ * When builtin, KUnit tests are all run via executor; this is done
+ * by placing the array of struct kunit_suite * in the .kunit_test_suites
+ * ELF section.
+ *
+ * An alternative is to build the tests as a module. Because modules do not
+ * support multiple initcall()s, we need to initialize an array of suites for a
+ * module.
+ *
+ */
+#define kunit_test_suites(...) \
+ __kunit_test_suites(__UNIQUE_ID(array), \
+ __UNIQUE_ID(suites), \
+ __VA_ARGS__)

#define kunit_test_suite(suite) kunit_test_suites(&suite)

diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile
index 724b94311ca36..c49f4ffb6273a 100644
--- a/lib/kunit/Makefile
+++ b/lib/kunit/Makefile
@@ -3,7 +3,8 @@ obj-$(CONFIG_KUNIT) += kunit.o
kunit-objs += test.o \
string-stream.o \
assert.o \
- try-catch.o
+ try-catch.o \
+ executor.o

ifeq ($(CONFIG_KUNIT_DEBUGFS),y)
kunit-objs += debugfs.o
diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
new file mode 100644
index 0000000000000..7015e7328dce7
--- /dev/null
+++ b/lib/kunit/executor.c
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <kunit/test.h>
+
+/*
+ * These symbols point to the .kunit_test_suites section and are defined in
+ * include/asm-generic/vmlinux.lds.h, and consequently must be extern.
+ */
+extern struct kunit_suite * const * const __kunit_suites_start[];
+extern struct kunit_suite * const * const __kunit_suites_end[];
+
+#if IS_BUILTIN(CONFIG_KUNIT)
+
+static int kunit_run_all_tests(void)
+{
+ struct kunit_suite * const * const *suites;
+
+ for (suites = __kunit_suites_start;
+ suites < __kunit_suites_end;
+ suites++)
+ __kunit_test_suites_init(*suites);
+
+ return 0;
+}
+
+late_initcall(kunit_run_all_tests);
+
+#endif /* IS_BUILTIN(CONFIG_KUNIT) */
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index ccb2ffad8dcfa..918dff400a9d7 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -380,7 +380,7 @@ static void kunit_init_suite(struct kunit_suite *suite)
kunit_debugfs_create_suite(suite);
}

-int __kunit_test_suites_init(struct kunit_suite **suites)
+int __kunit_test_suites_init(struct kunit_suite * const * const suites)
{
unsigned int i;

--
2.28.0.163.g6104cc2f0b6-goog