kunit: add unit test for filtering suites by names

This adds unit tests for kunit_filter_subsuite() and
kunit_filter_suites().

Note: what the executor means by "subsuite" is the array of suites
corresponding to each test file.

This patch lightly refactors executor.c to avoid the use of global
variables to make it testable.
It also includes a clever `kfree_at_end()` helper that makes this test
easier to write than it otherwise would have been.

Tested by running just the new tests using itself
$ ./tools/testing/kunit/kunit.py run '*exec*'

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

1 files changed, 19 insertions, 14 deletions

diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
index 7db619624437..acd1de436f59 100644
--- a/lib/kunit/executor.c
+++ b/lib/kunit/executor.c
@@ -14,8 +14,8 @@ extern struct kunit_suite * const * const __kunit_suites_end[];
 
 #if IS_BUILTIN(CONFIG_KUNIT)
 
-static char *filter_glob;
-module_param(filter_glob, charp, 0);
+static char *filter_glob_param;
+module_param_named(filter_glob, filter_glob_param, charp, 0);
 MODULE_PARM_DESC(filter_glob,
 		"Filter which KUnit test suites run at boot-time, e.g. list*");
 
@@ -23,7 +23,8 @@ static char *kunit_shutdown;
 core_param(kunit_shutdown, kunit_shutdown, charp, 0644);
 
 static struct kunit_suite * const *
-kunit_filter_subsuite(struct kunit_suite * const * const subsuite)
+kunit_filter_subsuite(struct kunit_suite * const * const subsuite,
+			const char *filter_glob)
 {
 	int i, n = 0;
 	struct kunit_suite **filtered;
@@ -56,19 +57,14 @@ struct suite_set {
 	struct kunit_suite * const * const *end;
 };
 
-static struct suite_set kunit_filter_suites(void)
+static struct suite_set kunit_filter_suites(const struct suite_set *suite_set,
+					    const char *filter_glob)
 {
 	int i;
 	struct kunit_suite * const **copy, * const *filtered_subsuite;
 	struct suite_set filtered;
 
-	const size_t max = __kunit_suites_end - __kunit_suites_start;
-
-	if (!filter_glob) {
-		filtered.start = __kunit_suites_start;
-		filtered.end = __kunit_suites_end;
-		return filtered;
-	}
+	const size_t max = suite_set->end - suite_set->start;
 
 	copy = kmalloc_array(max, sizeof(*filtered.start), GFP_KERNEL);
 	filtered.start = copy;
@@ -78,7 +74,7 @@ static struct suite_set kunit_filter_suites(void)
 	}
 
 	for (i = 0; i < max; ++i) {
-		filtered_subsuite = kunit_filter_subsuite(__kunit_suites_start[i]);
+		filtered_subsuite = kunit_filter_subsuite(suite_set->start[i], filter_glob);
 		if (filtered_subsuite)
 			*copy++ = filtered_subsuite;
 	}
@@ -116,15 +112,20 @@ static void kunit_print_tap_header(struct suite_set *suite_set)
 int kunit_run_all_tests(void)
 {
 	struct kunit_suite * const * const *suites;
+	struct suite_set suite_set = {
+		.start = __kunit_suites_start,
+		.end = __kunit_suites_end,
+	};
 
-	struct suite_set suite_set = kunit_filter_suites();
+	if (filter_glob_param)
+		suite_set = kunit_filter_suites(&suite_set, filter_glob_param);
 
 	kunit_print_tap_header(&suite_set);
 
 	for (suites = suite_set.start; suites < suite_set.end; suites++)
 		__kunit_test_suites_init(*suites);
 
-	if (filter_glob) { /* a copy was made of each array */
+	if (filter_glob_param) { /* a copy was made of each array */
 		for (suites = suite_set.start; suites < suite_set.end; suites++)
 			kfree(*suites);
 		kfree(suite_set.start);
@@ -135,4 +136,8 @@ int kunit_run_all_tests(void)
 	return 0;
 }
 
+#if IS_BUILTIN(CONFIG_KUNIT_TEST)
+#include "executor_test.c"
+#endif
+
 #endif /* IS_BUILTIN(CONFIG_KUNIT) */