[RFC,v2,4/9] kunit: Add ability to filter attributes

diff --git a/include/kunit/attributes.h b/include/kunit/attributes.h
index 9fcd184cce36..bc76a0b786d2 100644
--- a/include/kunit/attributes.h
+++ b/include/kunit/attributes.h
@@ -9,6 +9,20 @@ 
 #ifndef _KUNIT_ATTRIBUTES_H
 #define _KUNIT_ATTRIBUTES_H
 
+/*
+ * struct kunit_attr_filter - representation of attributes filter with the
+ * attribute object and string input
+ */
+struct kunit_attr_filter {
+	struct kunit_attr *attr;
+	char *input;
+};
+
+/*
+ * Returns the name of the filter's attribute.
+ */
+const char *kunit_attr_filter_name(struct kunit_attr_filter filter);
+
 /*
  * Print all test attributes for a test case or suite.
  * Output format for test cases: "# <test_name>.<attribute>: <value>"
@@ -16,4 +30,21 @@ 
  */
 void kunit_print_attr(void *test_or_suite, bool is_test, unsigned int test_level);
 
+/*
+ * Returns the number of fitlers in input.
+ */
+int kunit_get_filter_count(char *input);
+
+/*
+ * Parse attributes filter input and return an objects containing the
+ * attribute object and the string input of the next filter.
+ */
+struct kunit_attr_filter kunit_next_attr_filter(char **filters, int *err);
+
+/*
+ * Returns a copy of the suite containing only tests that pass the filter.
+ */
+struct kunit_suite *kunit_filter_attr_tests(const struct kunit_suite *const suite,
+		struct kunit_attr_filter filter, char *action, int *err);
+
 #endif /* _KUNIT_ATTRIBUTES_H */
diff --git a/lib/kunit/attributes.c b/lib/kunit/attributes.c
index 43dcb5de8b8f..91cbcacafba9 100644
--- a/lib/kunit/attributes.c
+++ b/lib/kunit/attributes.c
@@ -67,6 +67,104 @@  static const char *attr_string_to_string(void *attr, bool *to_free)
 	return (char *) attr;
 }
 
+/* Filter Methods */
+
+static const char op_list[] = "<>!=";
+
+/*
+ * Returns whether the inputted integer value matches the filter given
+ * by the operation string and inputted integer.
+ */
+static int int_filter(long val, const char *op, int input, int *err)
+{
+	if (!strncmp(op, "<=", 2))
+		return (val <= input);
+	else if (!strncmp(op, ">=", 2))
+		return (val >= input);
+	else if (!strncmp(op, "!=", 2))
+		return (val != input);
+	else if (!strncmp(op, ">", 1))
+		return (val > input);
+	else if (!strncmp(op, "<", 1))
+		return (val < input);
+	else if (!strncmp(op, "=", 1))
+		return (val == input);
+	*err = -EINVAL;
+	pr_err("kunit executor: invalid filter operation: %s\n", op);
+	return false;
+}
+
+/*
+ * Returns whether the inputted enum value "attr" matches the filter given
+ * by the input string. Note: the str_list includes the corresponding string
+ * list to the enum values.
+ */
+static int attr_enum_filter(void *attr, const char *input, int *err,
+		const char * const str_list[], int max)
+{
+	int i, j, input_int;
+	long test_val = (long)attr;
+	const char *input_val;
+
+	for (i = 0; input[i]; i++) {
+		if (!strchr(op_list, input[i])) {
+			input_val = input + i;
+			break;
+		}
+	}
+
+	if (!input_val) {
+		*err = -EINVAL;
+		pr_err("kunit executor: filter value not found: %s\n", input);
+		return false;
+	}
+
+	for (j = 0; j <= max; j++) {
+		if (!strcmp(input_val, str_list[j]))
+			input_int = j;
+	}
+
+	if (!input_int) {
+		*err = -EINVAL;
+		pr_err("kunit executor: invalid filter input: %s\n", input);
+		return false;
+	}
+
+	return int_filter(test_val, input, input_int, err);
+}
+
+static int attr_speed_filter(void *attr, const char *input, int *err)
+{
+	return attr_enum_filter(attr, input, err, speed_str_list, KUNIT_SPEED_MAX);
+}
+
+/*
+ * Returns whether the inputted string value (attr) matches the filter given
+ * by the input string.
+ */
+static int attr_string_filter(void *attr, const char *input, int *err)
+{
+	char *str = attr;
+
+	if (!strncmp(input, "<", 1)) {
+		*err = -EINVAL;
+		pr_err("kunit executor: invalid filter input: %s\n", input);
+		return false;
+	} else if (!strncmp(input, ">", 1)) {
+		*err = -EINVAL;
+		pr_err("kunit executor: invalid filter input: %s\n", input);
+		return false;
+	} else if (!strncmp(input, "!=", 2)) {
+		return (strcmp(input + 2, str) != 0);
+	} else if (!strncmp(input, "=", 1)) {
+		return (strcmp(input + 1, str) == 0);
+	}
+	*err = -EINVAL;
+	pr_err("kunit executor: invalid filter operation: %s\n", input);
+	return false;
+}
+
+
 /* Get Attribute Methods */
 
 static void *attr_speed_get(void *test_or_suite, bool is_test)
@@ -98,6 +196,7 @@  static const struct kunit_attr speed_attr = {
 	.name = "speed",
 	.get_attr = attr_speed_get,
 	.to_string = attr_speed_to_string,
+	.filter = attr_speed_filter,
 	.attr_default = (void *)KUNIT_SPEED_NORMAL,
 	.print = PRINT_ALWAYS,
 };
@@ -106,6 +205,7 @@  static const struct kunit_attr module_attr = {
 	.name = "module",
 	.get_attr = attr_module_get,
 	.to_string = attr_string_to_string,
+	.filter = attr_string_filter,
 	.attr_default = (void *)"",
 	.print = PRINT_SUITE,
 };
@@ -116,6 +216,11 @@  static struct kunit_attr kunit_attr_list[] = {speed_attr, module_attr};
 
 /* Helper Functions to Access Attributes */
 
+const char *kunit_attr_filter_name(struct kunit_attr_filter filter)
+{
+	return filter.attr->name;
+}
+
 void kunit_print_attr(void *test_or_suite, bool is_test, unsigned int test_level)
 {
 	int i;
@@ -148,3 +253,154 @@  void kunit_print_attr(void *test_or_suite, bool is_test, unsigned int test_level
 		}
 	}
 }
+
+/* Helper Functions to Filter Attributes */
+
+int kunit_get_filter_count(char *input)
+{
+	int i, comma_index, count = 0;
+
+	for (i = 0; input[i]; i++) {
+		if (input[i] == ',') {
+			if ((i - comma_index) > 1)
+				count++;
+			comma_index = i;
+		}
+	}
+	if ((i - comma_index) > 1)
+		count++;
+	return count;
+}
+
+struct kunit_attr_filter kunit_next_attr_filter(char **filters, int *err)
+{
+	struct kunit_attr_filter filter;
+	int i, j, comma_index, new_start_index;
+	int op_index = -1, attr_index = -1;
+	char op;
+	char *input = *filters;
+
+	/* Parse input until operation */
+	for (i = 0; input[i]; i++) {
+		if (op_index < 0 && strchr(op_list, input[i])) {
+			op_index = i;
+		} else if (!comma_index && input[i] == ',') {
+			comma_index = i;
+		} else if (comma_index && input[i] != ' ') {
+			new_start_index = i;
+			break;
+		}
+	}
+
+	if (op_index <= 0) {
+		*err = -EINVAL;
+		pr_err("kunit executor: filter operation not found: %s\n", input);
+		return filter;
+	}
+
+	/* Temporarily set operator to \0 character. */
+	op = input[op_index];
+	input[op_index] = '\0';
+
+	/* Find associated kunit_attr object */
+	for (j = 0; j < ARRAY_SIZE(kunit_attr_list); j++) {
+		if (!strcmp(input, kunit_attr_list[j].name)) {
+			attr_index = j;
+			break;
+		}
+	}
+
+	input[op_index] = op;
+
+	if (attr_index < 0) {
+		*err = -EINVAL;
+		pr_err("kunit executor: attribute not found: %s\n", input);
+	} else {
+		filter.attr = &kunit_attr_list[attr_index];
+	}
+
+	if (comma_index) {
+		input[comma_index] = '\0';
+		filter.input = input + op_index;
+		input = input + new_start_index;
+	} else {
+		filter.input = input + op_index;
+		input = NULL;
+	}
+
+	*filters = input;
+
+	return filter;
+}
+
+struct kunit_suite *kunit_filter_attr_tests(const struct kunit_suite *const suite,
+		struct kunit_attr_filter filter, char *action, int *err)
+{
+	int n = 0;
+	struct kunit_case *filtered, *test_case;
+	struct kunit_suite *copy;
+	void *suite_val, *test_val;
+	bool suite_result, test_result, default_result, result;
+
+	/* Allocate memory for new copy of suite and list of test cases */
+	copy = kmemdup(suite, sizeof(*copy), GFP_KERNEL);
+	if (!copy)
+		return ERR_PTR(-ENOMEM);
+
+	kunit_suite_for_each_test_case(suite, test_case) { n++; }
+
+	filtered = kcalloc(n + 1, sizeof(*filtered), GFP_KERNEL);
+	if (!filtered) {
+		kfree(copy);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	n = 0;
+
+	/* Save filtering result on default value */
+	default_result = filter.attr->filter(filter.attr->attr_default, filter.input, err);
+
+	/* Save suite attribute value and filtering result on that value */
+	suite_val = filter.attr->get_attr((void *)suite, false);
+	suite_result = filter.attr->filter(suite_val, filter.input, err);
+
+	/* For each test case, save test case if passes filtering. */
+	kunit_suite_for_each_test_case(suite, test_case) {
+		test_val = filter.attr->get_attr((void *) test_case, true);
+		test_result = filter.attr->filter(filter.attr->get_attr(test_case, true),
+				filter.input, err);
+
+		/*
+		 * If attribute value of test case is set, filter on that value.
+		 * If not, filter on suite value if set. If not, filter on
+		 * default value.
+		 */
+		result = false;
+		if (test_val) {
+			if (test_result)
+				result = true;
+		} else if (suite_val) {
+			if (suite_result)
+				result = true;
+		} else if (default_result) {
+			result = true;
+		}
+
+		if (result) {
+			filtered[n++] = *test_case;
+		} else if (action && strcmp(action, "skip") == 0) {
+			test_case->status = KUNIT_SKIPPED;
+			filtered[n++] = *test_case;
+		}
+	}
+
+	if (n == 0) {
+		kfree(copy);
+		kfree(filtered);
+		return NULL;
+	}
+
+	copy->test_cases = filtered;
+
+	return copy;
+}
diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
index 12e38a48a5cc..c286ae47435a 100644
--- a/lib/kunit/executor.c
+++ b/lib/kunit/executor.c
@@ -17,6 +17,9 @@  extern struct kunit_suite * const __kunit_suites_end[];
 
 static char *filter_glob_param;
 static char *action_param;
+static char *filter_param;
+static char *filter_action_param;
+
 
 module_param_named(filter_glob, filter_glob_param, charp, 0);
 MODULE_PARM_DESC(filter_glob,
@@ -27,15 +30,23 @@  MODULE_PARM_DESC(action,
 		 "<none>: run the tests like normal\n"
 		 "'list' to list test names instead of running them.\n"
 		 "'list_attr' to list test names and attributes instead of running them.\n");
+module_param_named(filter, filter_param, charp, 0);
+MODULE_PARM_DESC(filter,
+		"Filter which KUnit test suites/tests run at boot-time using attributes, e.g. speed>slow");
+module_param_named(filter_action, filter_action_param, charp, 0);
+MODULE_PARM_DESC(filter_action,
+		"Changes behavior of filtered tests using attributes, valid values are:\n"
+		"<none>: do not run filtered tests as normal\n"
+		"'skip': skip all filtered tests instead so tests will appear in output\n");
 
 /* glob_match() needs NULL terminated strings, so we need a copy of filter_glob_param. */
-struct kunit_test_filter {
+struct kunit_glob_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,
+static void kunit_parse_glob_filter(struct kunit_glob_filter *parsed,
 				    const char *filter_glob)
 {
 	const int len = strlen(filter_glob);
@@ -57,7 +68,7 @@  static void kunit_parse_filter_glob(struct kunit_test_filter *parsed,
 
 /* Create a copy of suite with only tests that match test_glob. */
 static struct kunit_suite *
-kunit_filter_tests(const struct kunit_suite *const suite, const char *test_glob)
+kunit_filter_glob_tests(const struct kunit_suite *const suite, const char *test_glob)
 {
 	int n = 0;
 	struct kunit_case *filtered, *test_case;
@@ -111,12 +122,15 @@  static void kunit_free_suite_set(struct suite_set suite_set)
 
 static struct suite_set kunit_filter_suites(const struct suite_set *suite_set,
 					    const char *filter_glob,
+						char *filters,
+						char *filter_action,
 					    int *err)
 {
-	int i;
-	struct kunit_suite **copy, *filtered_suite;
+	int i, j, k, filter_count;
+	struct kunit_suite **copy, *filtered_suite, *new_filtered_suite;
 	struct suite_set filtered;
-	struct kunit_test_filter filter;
+	struct kunit_glob_filter parsed_glob;
+	struct kunit_attr_filter *parsed_filters;
 
 	const size_t max = suite_set->end - suite_set->start;
 
@@ -127,17 +141,52 @@  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; &suite_set->start[i] != suite_set->end; i++) {
-		if (!glob_match(filter.suite_glob, suite_set->start[i]->name))
-			continue;
+	if (filter_glob)
+		kunit_parse_glob_filter(&parsed_glob, filter_glob);
 
-		filtered_suite = kunit_filter_tests(suite_set->start[i], filter.test_glob);
-		if (IS_ERR(filtered_suite)) {
-			*err = PTR_ERR(filtered_suite);
+	/* Parse attribute filters */
+	if (filters) {
+		filter_count = kunit_get_filter_count(filters);
+		parsed_filters = kcalloc(filter_count + 1, sizeof(*parsed_filters), GFP_KERNEL);
+		for (j = 0; j < filter_count; j++)
+			parsed_filters[j] = kunit_next_attr_filter(&filters, err);
+		if (*err)
 			return filtered;
+	}
+
+	for (i = 0; &suite_set->start[i] != suite_set->end; i++) {
+		filtered_suite = suite_set->start[i];
+		if (filter_glob) {
+			if (!glob_match(parsed_glob.suite_glob, filtered_suite->name))
+				continue;
+			filtered_suite = kunit_filter_glob_tests(filtered_suite,
+					parsed_glob.test_glob);
+			if (IS_ERR(filtered_suite)) {
+				*err = PTR_ERR(filtered_suite);
+				return filtered;
+			}
+		}
+		if (filter_count) {
+			for (k = 0; k < filter_count; k++) {
+				new_filtered_suite = kunit_filter_attr_tests(filtered_suite,
+						parsed_filters[k], filter_action, err);
+
+				/* Free previous copy of suite */
+				if (k > 0 || filter_glob)
+					kfree(filtered_suite);
+				filtered_suite = new_filtered_suite;
+
+				if (*err)
+					return filtered;
+				if (IS_ERR(filtered_suite)) {
+					*err = PTR_ERR(filtered_suite);
+					return filtered;
+				}
+				if (!filtered_suite)
+					break;
+			}
 		}
+
 		if (!filtered_suite)
 			continue;
 
@@ -145,8 +194,14 @@  static struct suite_set kunit_filter_suites(const struct suite_set *suite_set,
 	}
 	filtered.end = copy;
 
-	kfree(filter.suite_glob);
-	kfree(filter.test_glob);
+	if (filter_glob) {
+		kfree(parsed_glob.suite_glob);
+		kfree(parsed_glob.test_glob);
+	}
+
+	if (filter_count)
+		kfree(parsed_filters);
+
 	return filtered;
 }
 
@@ -206,8 +261,9 @@  int kunit_run_all_tests(void)
 		goto out;
 	}
 
-	if (filter_glob_param) {
-		suite_set = kunit_filter_suites(&suite_set, filter_glob_param, &err);
+	if (filter_glob_param || filter_param) {
+		suite_set = kunit_filter_suites(&suite_set, filter_glob_param,
+				filter_param, filter_action_param, &err);
 		if (err) {
 			pr_err("kunit executor: error filtering suites: %d\n", err);
 			goto out;
@@ -223,7 +279,7 @@  int kunit_run_all_tests(void)
 	else
 		pr_err("kunit executor: unknown action '%s'\n", action_param);
 
-	if (filter_glob_param) { /* a copy was made of each suite */
+	if (filter_glob_param || filter_param) { /* a copy was made of each suite */
 		kunit_free_suite_set(suite_set);
 	}
 
diff --git a/lib/kunit/executor_test.c b/lib/kunit/executor_test.c
index ce6749af374d..d7ab069324b5 100644
--- a/lib/kunit/executor_test.c
+++ b/lib/kunit/executor_test.c
@@ -24,15 +24,15 @@  static struct kunit_case dummy_test_cases[] = {
 
 static void parse_filter_test(struct kunit *test)
 {
-	struct kunit_test_filter filter = {NULL, NULL};
+	struct kunit_glob_filter filter = {NULL, NULL};
 
-	kunit_parse_filter_glob(&filter, "suite");
+	kunit_parse_glob_filter(&filter, "suite");
 	KUNIT_EXPECT_STREQ(test, filter.suite_glob, "suite");
 	KUNIT_EXPECT_FALSE(test, filter.test_glob);
 	kfree(filter.suite_glob);
 	kfree(filter.test_glob);
 
-	kunit_parse_filter_glob(&filter, "suite.test");
+	kunit_parse_glob_filter(&filter, "suite.test");
 	KUNIT_EXPECT_STREQ(test, filter.suite_glob, "suite");
 	KUNIT_EXPECT_STREQ(test, filter.test_glob, "test");
 	kfree(filter.suite_glob);
@@ -50,7 +50,7 @@  static void filter_suites_test(struct kunit *test)
 	subsuite[1] = alloc_fake_suite(test, "suite2", dummy_test_cases);
 
 	/* Want: suite1, suite2, NULL -> suite2, NULL */
-	got = kunit_filter_suites(&suite_set, "suite2", &err);
+	got = kunit_filter_suites(&suite_set, "suite2", NULL, NULL, &err);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, got.start);
 	KUNIT_ASSERT_EQ(test, err, 0);
 	kfree_at_end(test, got.start);
@@ -74,7 +74,7 @@  static void filter_suites_test_glob_test(struct kunit *test)
 	subsuite[1] = alloc_fake_suite(test, "suite2", dummy_test_cases);
 
 	/* Want: suite1, suite2, NULL -> suite2 (just test1), NULL */
-	got = kunit_filter_suites(&suite_set, "suite2.test2", &err);
+	got = kunit_filter_suites(&suite_set, "suite2.test2", NULL, NULL, &err);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, got.start);
 	KUNIT_ASSERT_EQ(test, err, 0);
 	kfree_at_end(test, got.start);
@@ -100,7 +100,7 @@  static void filter_suites_to_empty_test(struct kunit *test)
 	subsuite[0] = alloc_fake_suite(test, "suite1", dummy_test_cases);
 	subsuite[1] = alloc_fake_suite(test, "suite2", dummy_test_cases);
 
-	got = kunit_filter_suites(&suite_set, "not_found", &err);
+	got = kunit_filter_suites(&suite_set, "not_found", NULL, NULL, &err);
 	KUNIT_ASSERT_EQ(test, err, 0);
 	kfree_at_end(test, got.start); /* just in case */
 
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index 9ee55139ecd1..cb9797fa6303 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -613,18 +613,22 @@  int kunit_run_tests(struct kunit_suite *suite)
 	kunit_suite_for_each_test_case(suite, test_case) {
 		struct kunit test = { .param_value = NULL, .param_index = 0 };
 		struct kunit_result_stats param_stats = { 0 };
-		test_case->status = KUNIT_SKIPPED;
 
 		kunit_init_test(&test, test_case->name, test_case->log);
-
-		if (!test_case->generate_params) {
+		if (test_case->status == KUNIT_SKIPPED) {
+			/* Test marked as skip */
+			test.status = KUNIT_SKIPPED;
+			kunit_update_stats(&param_stats, test.status);
+		} else if (!test_case->generate_params) {
 			/* Non-parameterised test. */
+			test_case->status = KUNIT_SKIPPED;
 			kunit_run_case_catch_errors(suite, test_case, &test);
 			kunit_update_stats(&param_stats, test.status);
 		} else {
 			/* Get initial param. */
 			param_desc[0] = '\0';
 			test.param_value = test_case->generate_params(NULL, param_desc);
+			test_case->status = KUNIT_SKIPPED;
 			kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT
 				  "KTAP version 1\n");
 			kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT