Le 05/06/2026 à 12:28 AM, Vaibhav Jain a écrit :

Currently, KUnit provides mechanisms to skip individual test cases, but
there is no way to skip an entire test suite based on runtime conditions
checked during suite initialization. This limitation forces test suites
to either fail or skip tests individually when certain prerequisites are
not available.

To address this limitation, the patch adds a 'status' field to struct
kunit_suite that allows suite_init callbacks to mark the entire suite as
KUNIT_SKIPPED. When a suite is marked as skipped, all test cases within
that suite are bypassed without execution.

The patch proposes changes to kunit_suite_has_succeeded() to check suite
status before evaluating individual test case results. Also
kunit_run_tests() is updated to skip suite execution if 'kunit_suite.status'
is set to KUNIT_SKIPPED, thats either set before suite_init or by the
suite_init callback itself.

This enables test suites to perform runtime capability checks in their
'suite_init' callback and gracefully skip all tests when prerequisites are
not met, rather than reporting failures or requiring each test case to
perform redundant checks.

Signed-off-by: Vaibhav Jain <redacted>
---

Thanks — this is great! There are a few cases it's not handling
properly, though, particularly with respect to the debugfs support.

I think we need to:
- Reset suite->status to KUNIT_SUCCESS in kunit_init_suite(), so that a
suite which is re-run via debugfs isn't automatically skipped again.
- Fix the result handling in debugfs to handle skipped suites.
- (Optional) Maybe we could get rid of kunit_suite::suite_init_err now
that there's a specific status value. That'd have to be done carefully
to preserve all of the semantics, though.

Here's a quick (and slightly hacky) patch to fix the first couple of issues:
---

diff --git a/lib/kunit/debugfs.c b/lib/kunit/debugfs.c
index 9c326f1837bd..23d34bfdba95 100644
--- a/lib/kunit/debugfs.c
+++ b/lib/kunit/debugfs.c

@@ -58,6 +58,22 @@ static void debugfs_print_result(struct seq_file

*seq, struct string_stream *log
 	spin_unlock(&log->lock);
 }

+/* Print the result line for a suite. */
+static void debugfs_print_ok_not_ok(struct seq_file *seq,
+				    enum kunit_status status,
+				    size_t test_number,
+				    const char *description,
+				    const char *directive)
+{
+	const char *directive_header = (status == KUNIT_SKIPPED) ? " # SKIP "
: "";
+	const char *directive_body = (status == KUNIT_SKIPPED) ? directive : "";
+
+	seq_printf(seq, "%s %zd %s%s%s\n",
+		   kunit_status_to_ok_not_ok(status),
+		   test_number, description, directive_header,
+		   directive_body);
+}
+
 /*
  * /sys/kernel/debug/kunit/<testsuite>/results shows all results for
testsuite.
  */

@@ -77,17 +93,17 @@ static int debugfs_print_results(struct seq_file

*seq, void *v)
 	seq_puts(seq, "1..1\n");

 	/* Print suite header because it is not stored in the test logs. */
-	seq_puts(seq, KUNIT_SUBTEST_INDENT "KTAP version 1\n");
-	seq_printf(seq, KUNIT_SUBTEST_INDENT "# Subtest: %s\n", suite->name);
-	seq_printf(seq, KUNIT_SUBTEST_INDENT "1..%zd\n",
kunit_suite_num_test_cases(suite));
-
-	kunit_suite_for_each_test_case(suite, test_case)
-		debugfs_print_result(seq, test_case->log);
+	if (suite->status != KUNIT_SKIPPED) {
+		seq_puts(seq, KUNIT_SUBTEST_INDENT "KTAP version 1\n");
+		seq_printf(seq, KUNIT_SUBTEST_INDENT "# Subtest: %s\n", suite->name);
+		seq_printf(seq, KUNIT_SUBTEST_INDENT "1..%zd\n",
kunit_suite_num_test_cases(suite));

+		kunit_suite_for_each_test_case(suite, test_case)
+			debugfs_print_result(seq, test_case->log);
+	}
 	debugfs_print_result(seq, suite->log);

-	seq_printf(seq, "%s %d %s\n",
-		   kunit_status_to_ok_not_ok(success), 1, suite->name);
+	debugfs_print_ok_not_ok(seq, success, 1, suite->name,
suite->status_comment);
 	return 0;
 }

diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index c0ae45a22b2c..2ff145796450 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c

@@ -798,9 +798,6 @@ int kunit_run_tests(struct kunit_suite *suite)
 	/* Taint the kernel so we know we've run tests. */
 	add_taint(TAINT_TEST, LOCKDEP_STILL_OK);

-	if (suite->status == KUNIT_SKIPPED)
-		goto suite_end;
-
 	if (suite->suite_init) {
 		suite->suite_init_err = suite->suite_init(suite);
 		if (suite->suite_init_err) {

@@ -836,6 +833,7 @@ static void kunit_init_suite(struct kunit_suite *suite)
 	kunit_debugfs_create_suite(suite);
 	suite->status_comment[0] = '\0';
 	suite->suite_init_err = 0;
+	suite->status = KUNIT_SUCCESS;

 	if (suite->log)
 		string_stream_clear(suite->log);
---

Do we want this? If a test is run more than once, we probably want to
re-run suite_init so that we can tell if we should still skip it.

While I don't think it's likely that a test which was previously skipped
will suddenly become available, it's not impossible with, e.g., CPU hotplug.

 	if (suite->suite_init) {
 		suite->suite_init_err = suite->suite_init(suite);
 		if (suite->suite_init_err) {
+			suite->status = KUNIT_FAILURE;
 			kunit_err(suite, KUNIT_SUBTEST_INDENT
 				  "# failed to initialize (%d)", suite->suite_init_err);
 			goto suite_end;
+
+		} else if (suite->status == KUNIT_SKIPPED) {
+			/* Skip this kunit suite */
+			goto suite_end;
 		}
 	}
 

Cheers,
-- David