kunit: tool: allow filtering test cases via glob

Commit 1d71307a6f94 ("kunit: add unit test for filtering suites by
names") introduced the ability to filter which suites we run via glob.

This change extends it so we can also filter individual test cases
inside of suites as well.

This is quite useful when, e.g.
* trying to run just the tests cases you've just added or are working on
* trying to debug issues with test hermeticity

Examples:
$ ./tools/testing/kunit/kunit.py run --kunitconfig=lib/kunit '*exec*.parse*'
...
============================================================
======== [PASSED] kunit_executor_test ========
[PASSED] parse_filter_test
============================================================
Testing complete. 1 tests run. 0 failed. 0 crashed.

$ ./tools/testing/kunit/kunit.py run --kunitconfig=lib/kunit '*.no_matching_tests'
...
[ERROR] no tests run!

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

1 files changed, 96 insertions, 11 deletions

diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
index acd1de436f59..bab3ab940acc 100644
--- a/lib/kunit/executor.c
+++ b/lib/kunit/executor.c
@@ -17,21 +17,80 @@ extern struct kunit_suite * const * const __kunit_suites_end[];
 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*");
+		"Filter which KUnit test suites/tests run at boot-time, e.g. list* or list*.*del_test");
+
+/* glob_match() needs NULL terminated strings, so we need a copy of filter_glob_param. */
+struct kunit_test_filter {
+	char *suite_glob;
+	char *test_glob;
+};
+
+/* Split "suite_glob.test_glob" into two. Assumes filter_glob is not empty. */
+static void kunit_parse_filter_glob(struct kunit_test_filter *parsed,
+				    const char *filter_glob)
+{
+	const int len = strlen(filter_glob);
+	const char *period = strchr(filter_glob, '.');
+
+	if (!period) {
+		parsed->suite_glob = kmalloc(len, GFP_KERNEL);
+		parsed->test_glob = NULL;
+		strcpy(parsed->suite_glob, filter_glob);
+		return;
+	}
+
+	parsed->suite_glob = kzalloc(period - filter_glob + 1, GFP_KERNEL);
+	parsed->test_glob = kzalloc(len - (period - filter_glob) + 1, GFP_KERNEL);
+
+	strncpy(parsed->suite_glob, filter_glob, period - filter_glob);
+	strncpy(parsed->test_glob, period + 1, len - (period - filter_glob));
+}
+
+/* Create a copy of suite with only tests that match test_glob. */
+static struct kunit_suite *
+kunit_filter_tests(struct kunit_suite *const suite, const char *test_glob)
+{
+	int n = 0;
+	struct kunit_case *filtered, *test_case;
+	struct kunit_suite *copy;
+
+	kunit_suite_for_each_test_case(suite, test_case) {
+		if (!test_glob || glob_match(test_glob, test_case->name))
+			++n;
+	}
+
+	if (n == 0)
+		return NULL;
+
+	/* Use memcpy to workaround copy->name being const. */
+	copy = kmalloc(sizeof(*copy), GFP_KERNEL);
+	memcpy(copy, suite, sizeof(*copy));
+
+	filtered = kcalloc(n + 1, sizeof(*filtered), GFP_KERNEL);
+
+	n = 0;
+	kunit_suite_for_each_test_case(suite, test_case) {
+		if (!test_glob || glob_match(test_glob, test_case->name))
+			filtered[n++] = *test_case;
+	}
+
+	copy->test_cases = filtered;
+	return copy;
+}
 
 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,
-			const char *filter_glob)
+		      struct kunit_test_filter *filter)
 {
 	int i, n = 0;
-	struct kunit_suite **filtered;
+	struct kunit_suite **filtered, *filtered_suite;
 
 	n = 0;
-	for (i = 0; subsuite[i] != NULL; ++i) {
-		if (glob_match(filter_glob, subsuite[i]->name))
+	for (i = 0; subsuite[i]; ++i) {
+		if (glob_match(filter->suite_glob, subsuite[i]->name))
 			++n;
 	}
 
@@ -44,8 +103,11 @@ kunit_filter_subsuite(struct kunit_suite * const * const subsuite,
 
 	n = 0;
 	for (i = 0; subsuite[i] != NULL; ++i) {
-		if (glob_match(filter_glob, subsuite[i]->name))
-			filtered[n++] = subsuite[i];
+		if (!glob_match(filter->suite_glob, subsuite[i]->name))
+			continue;
+		filtered_suite = kunit_filter_tests(subsuite[i], filter->test_glob);
+		if (filtered_suite)
+			filtered[n++] = filtered_suite;
 	}
 	filtered[n] = NULL;
 
@@ -57,12 +119,32 @@ struct suite_set {
 	struct kunit_suite * const * const *end;
 };
 
+static void kunit_free_subsuite(struct kunit_suite * const *subsuite)
+{
+	unsigned int i;
+
+	for (i = 0; subsuite[i]; i++)
+		kfree(subsuite[i]);
+
+	kfree(subsuite);
+}
+
+static void kunit_free_suite_set(struct suite_set suite_set)
+{
+	struct kunit_suite * const * const *suites;
+
+	for (suites = suite_set.start; suites < suite_set.end; suites++)
+		kunit_free_subsuite(*suites);
+	kfree(suite_set.start);
+}
+
 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;
+	struct kunit_test_filter filter;
 
 	const size_t max = suite_set->end - suite_set->start;
 
@@ -73,12 +155,17 @@ static struct suite_set kunit_filter_suites(const struct suite_set *suite_set,
 		return filtered;
 	}
 
+	kunit_parse_filter_glob(&filter, filter_glob);
+
 	for (i = 0; i < max; ++i) {
-		filtered_subsuite = kunit_filter_subsuite(suite_set->start[i], filter_glob);
+		filtered_subsuite = kunit_filter_subsuite(suite_set->start[i], &filter);
 		if (filtered_subsuite)
 			*copy++ = filtered_subsuite;
 	}
 	filtered.end = copy;
+
+	kfree(filter.suite_glob);
+	kfree(filter.test_glob);
 	return filtered;
 }
 
@@ -126,9 +213,7 @@ int kunit_run_all_tests(void)
 		__kunit_test_suites_init(*suites);
 
 	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);
+		kunit_free_suite_set(suite_set);
 	}
 
 	kunit_handle_shutdown();