[RFC 0/7] selftests: kselftest_harness: use common result printing helper

[RFC 0/7] selftests: kselftest_harness: use common result printing helper

[Jakub Kicinski]

Add a common result printing helper and always include test name
in the result line. Previously when SKIP or XPASS would happen
we printed:

  ok 1 # SKIP unknown

without the test name. Now we'll print:

  ok 1 global.no_pad # SKIP unknown

This appears to be more inline with:
https://docs.kernel.org/dev-tools/ktap.html
and makes parsing results easier.

First 3 patches rearrange kselftest_harness to use exit code
as an enum rather than separate passed/skip/xfail members.

Rest of the series builds a ksft_test_result_code() helper.

This series is on top of:
https://lore.kernel.org/all/20240216002619.1999225-1-kuba@kernel.org/

Jakub Kicinski (7):
  selftests: kselftest_harness: generate test name once
  selftests: kselftest_harness: save full exit code in metadata
  selftests: kselftest_harness: use exit code to store skip and xfail
  selftests: kselftest: add ksft_test_result_code(), handling all exit
    codes
  selftests: kselftest_harness: print test name for SKIP and XFAIL
  selftests: kselftest_harness: let ksft_test_result_code() handle line
    termination
  selftests: kselftest_harness: let PASS / FAIL provide diagnostic

 tools/testing/selftests/kselftest.h         | 45 ++++++++++
 tools/testing/selftests/kselftest_harness.h | 96 ++++++++++-----------
 tools/testing/selftests/net/tls.c           |  2 +-
 3 files changed, 91 insertions(+), 52 deletions(-)

-- 
2.43.0

[RFC 1/7] selftests: kselftest_harness: generate test name once

[Jakub Kicinski]

Since we added variant support generating full test case
name takes 4 string arguments. We're about to need it
in another two places. Stop the duplication and print
once into a temporary buffer.

Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/kselftest_harness.h | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 04177813930b..b271cb721b81 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -56,6 +56,7 @@
 #include <asm/types.h>
 #include <ctype.h>
 #include <errno.h>
+#include <limits.h>
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
@@ -1140,6 +1141,8 @@ void __run_test(struct __fixture_metadata *f,
 		struct __fixture_variant_metadata *variant,
 		struct __test_metadata *t)
 {
+	char test_name[LINE_MAX];
+
 	/* reset test struct */
 	t->passed = 1;
 	t->skip = 0;
@@ -1149,8 +1152,10 @@ void __run_test(struct __fixture_metadata *f,
 	memset(t->results->reason, 0, sizeof(t->results->reason));
 	t->results->step = 1;
 
-	ksft_print_msg(" RUN           %s%s%s.%s ...\n",
-	       f->name, variant->name[0] ? "." : "", variant->name, t->name);
+	snprintf(test_name, sizeof(test_name), "%s%s%s.%s",
+		 f->name, variant->name[0] ? "." : "", variant->name, t->name);
+
+	ksft_print_msg(" RUN           %s ...\n", test_name);
 
 	/* Make sure output buffers are flushed before fork */
 	fflush(stdout);
@@ -1174,8 +1179,8 @@ void __run_test(struct __fixture_metadata *f,
 	} else {
 		__wait_for_test(t);
 	}
-	ksft_print_msg("         %4s  %s%s%s.%s\n", t->passed ? "OK" : "FAIL",
-	       f->name, variant->name[0] ? "." : "", variant->name, t->name);
+	ksft_print_msg("         %4s  %s\n",
+		       t->passed ? "OK" : "FAIL", test_name);
 
 	if (t->skip)
 		ksft_test_result_skip("%s\n", t->results->reason[0] ?
@@ -1184,8 +1189,7 @@ void __run_test(struct __fixture_metadata *f,
 		ksft_test_result_xfail("%s\n", t->results->reason[0] ?
 				       t->results->reason : "unknown");
 	else
-		ksft_test_result(t->passed, "%s%s%s.%s\n",
-			f->name, variant->name[0] ? "." : "", variant->name, t->name);
+		ksft_test_result(t->passed, "%s\n", test_name);
 }
 
 static int test_harness_run(int argc, char **argv)
-- 
2.43.0

[RFC 2/7] selftests: kselftest_harness: save full exit code in metadata

[Jakub Kicinski]

Instead of tracking passed = 0/1 rename the field to exit_code
and invert the values so that they match the KSFT_* exit codes.
This will allow us to fold SKIP / XFAIL into the same value.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/kselftest_harness.h | 52 ++++++++++++---------
 tools/testing/selftests/net/tls.c           |  2 +-
 2 files changed, 30 insertions(+), 24 deletions(-)

diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index b271cb721b81..70366864ffd9 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -136,7 +136,7 @@
 		fprintf(TH_LOG_STREAM, "#      SKIP      %s\n", \
 			_metadata->results->reason); \
 	} \
-	_metadata->passed = 1; \
+	_metadata->exit_code = KSFT_PASS; \
 	_metadata->skip = 1; \
 	_metadata->trigger = 0; \
 	statement; \
@@ -163,7 +163,7 @@
 		fprintf(TH_LOG_STREAM, "#      XFAIL     %s\n", \
 			_metadata->results->reason); \
 	} \
-	_metadata->passed = 1; \
+	_metadata->exit_code = KSFT_PASS; \
 	_metadata->xfail = 1; \
 	_metadata->trigger = 0; \
 	statement; \
@@ -416,7 +416,7 @@
 		if (setjmp(_metadata->env) == 0) { \
 			fixture_name##_setup(_metadata, &self, variant->data); \
 			/* Let setup failure terminate early. */ \
-                       if (!_metadata->passed || _metadata->skip) \
+			if (!__test_passed(_metadata) || _metadata->skip) \
 				return; \
 			_metadata->setup_completed = true; \
 			fixture_name##_##test_name(_metadata, &self, variant->data); \
@@ -723,7 +723,7 @@
 			__bail(_assert, _metadata))
 
 #define __INC_STEP(_metadata) \
-	if (_metadata->passed) \
+	if (__test_passed(_metadata))	\
 		_metadata->results->step++;
 
 #define is_signed_type(var)       (!!(((__typeof__(var))(-1)) < (__typeof__(var))1))
@@ -769,7 +769,7 @@
 			break; \
 			} \
 		} \
-		_metadata->passed = 0; \
+		_metadata->exit_code = KSFT_FAIL; \
 		/* Ensure the optional handler is triggered */ \
 		_metadata->trigger = 1; \
 	} \
@@ -781,7 +781,7 @@
 	if (_assert) __INC_STEP(_metadata); \
 	if (!(strcmp(__exp, __seen) _t 0))  { \
 		__TH_LOG("Expected '%s' %s '%s'.", __exp, #_t, __seen); \
-		_metadata->passed = 0; \
+		_metadata->exit_code = KSFT_FAIL; \
 		_metadata->trigger = 1; \
 	} \
 } while (0); OPTIONAL_HANDLER(_assert)
@@ -860,7 +860,7 @@ struct __test_metadata {
 	pid_t pid;	/* pid of test when being run */
 	struct __fixture_metadata *fixture;
 	int termsig;
-	int passed;
+	int exit_code;
 	int skip;	/* did SKIP get used? */
 	int xfail;	/* did XFAIL get used? */
 	int trigger; /* extra handler after the evaluation */
@@ -874,6 +874,12 @@ struct __test_metadata {
 	struct __test_metadata *prev, *next;
 };
 
+static inline bool __test_passed(struct __test_metadata *metadata)
+{
+	return metadata->exit_code != KSFT_FAIL &&
+	       metadata->exit_code <= KSFT_SKIP;
+}
+
 /*
  * Since constructors are called in reverse order, reverse the test
  * list so tests are run in source declaration order.
@@ -941,7 +947,7 @@ void __wait_for_test(struct __test_metadata *t)
 	int status;
 
 	if (sigaction(SIGALRM, &action, &saved_action)) {
-		t->passed = 0;
+		t->exit_code = KSFT_FAIL;
 		fprintf(TH_LOG_STREAM,
 			"# %s: unable to install SIGALRM handler\n",
 			t->name);
@@ -953,7 +959,7 @@ void __wait_for_test(struct __test_metadata *t)
 	waitpid(t->pid, &status, 0);
 	alarm(0);
 	if (sigaction(SIGALRM, &saved_action, NULL)) {
-		t->passed = 0;
+		t->exit_code = KSFT_FAIL;
 		fprintf(TH_LOG_STREAM,
 			"# %s: unable to uninstall SIGALRM handler\n",
 			t->name);
@@ -962,19 +968,19 @@ void __wait_for_test(struct __test_metadata *t)
 	__active_test = NULL;
 
 	if (t->timed_out) {
-		t->passed = 0;
+		t->exit_code = KSFT_FAIL;
 		fprintf(TH_LOG_STREAM,
 			"# %s: Test terminated by timeout\n", t->name);
 	} else if (WIFEXITED(status)) {
 		if (WEXITSTATUS(status) == KSFT_SKIP) {
 			/* SKIP */
-			t->passed = 1;
+			t->exit_code = KSFT_PASS;
 			t->skip = 1;
 		} else if (WEXITSTATUS(status) == KSFT_XFAIL) {
-			t->passed = 1;
+			t->exit_code = KSFT_PASS;
 			t->xfail = 1;
 		} else if (t->termsig != -1) {
-			t->passed = 0;
+			t->exit_code = KSFT_FAIL;
 			fprintf(TH_LOG_STREAM,
 				"# %s: Test exited normally instead of by signal (code: %d)\n",
 				t->name,
@@ -983,11 +989,11 @@ void __wait_for_test(struct __test_metadata *t)
 			switch (WEXITSTATUS(status)) {
 			/* Success */
 			case KSFT_PASS:
-				t->passed = 1;
+				t->exit_code = KSFT_PASS;
 				break;
 			/* Other failure, assume step report. */
 			default:
-				t->passed = 0;
+				t->exit_code = KSFT_FAIL;
 				fprintf(TH_LOG_STREAM,
 					"# %s: Test failed at step #%d\n",
 					t->name,
@@ -995,13 +1001,13 @@ void __wait_for_test(struct __test_metadata *t)
 			}
 		}
 	} else if (WIFSIGNALED(status)) {
-		t->passed = 0;
+		t->exit_code = KSFT_FAIL;
 		if (WTERMSIG(status) == SIGABRT) {
 			fprintf(TH_LOG_STREAM,
 				"# %s: Test terminated by assertion\n",
 				t->name);
 		} else if (WTERMSIG(status) == t->termsig) {
-			t->passed = 1;
+			t->exit_code = KSFT_PASS;
 		} else {
 			fprintf(TH_LOG_STREAM,
 				"# %s: Test terminated unexpectedly by signal %d\n",
@@ -1144,7 +1150,7 @@ void __run_test(struct __fixture_metadata *f,
 	char test_name[LINE_MAX];
 
 	/* reset test struct */
-	t->passed = 1;
+	t->exit_code = KSFT_PASS;
 	t->skip = 0;
 	t->xfail = 0;
 	t->trigger = 0;
@@ -1164,7 +1170,7 @@ void __run_test(struct __fixture_metadata *f,
 	t->pid = fork();
 	if (t->pid < 0) {
 		ksft_print_msg("ERROR SPAWNING TEST CHILD\n");
-		t->passed = 0;
+		t->exit_code = KSFT_FAIL;
 	} else if (t->pid == 0) {
 		setpgrp();
 		t->fn(t, variant);
@@ -1172,7 +1178,7 @@ void __run_test(struct __fixture_metadata *f,
 			_exit(KSFT_SKIP);
 		if (t->xfail)
 			_exit(KSFT_XFAIL);
-		if (t->passed)
+		if (__test_passed(t))
 			_exit(KSFT_PASS);
 		/* Something else happened. */
 		_exit(KSFT_FAIL);
@@ -1180,7 +1186,7 @@ void __run_test(struct __fixture_metadata *f,
 		__wait_for_test(t);
 	}
 	ksft_print_msg("         %4s  %s\n",
-		       t->passed ? "OK" : "FAIL", test_name);
+		       __test_passed(t) ? "OK" : "FAIL", test_name);
 
 	if (t->skip)
 		ksft_test_result_skip("%s\n", t->results->reason[0] ?
@@ -1189,7 +1195,7 @@ void __run_test(struct __fixture_metadata *f,
 		ksft_test_result_xfail("%s\n", t->results->reason[0] ?
 				       t->results->reason : "unknown");
 	else
-		ksft_test_result(t->passed, "%s\n", test_name);
+		ksft_test_result(__test_passed(t), "%s\n", test_name);
 }
 
 static int test_harness_run(int argc, char **argv)
@@ -1237,7 +1243,7 @@ static int test_harness_run(int argc, char **argv)
 				t->results = results;
 				__run_test(f, v, t);
 				t->results = NULL;
-				if (t->passed)
+				if (__test_passed(t))
 					pass_count++;
 				else
 					ret = 1;
diff --git a/tools/testing/selftests/net/tls.c b/tools/testing/selftests/net/tls.c
index 49c84602707f..046d1ccedcf3 100644
--- a/tools/testing/selftests/net/tls.c
+++ b/tools/testing/selftests/net/tls.c
@@ -1882,7 +1882,7 @@ TEST_F(tls_err, poll_partial_rec_async)
 		pfd.events = POLLIN;
 		EXPECT_EQ(poll(&pfd, 1, 20), 1);
 
-		exit(!_metadata->passed);
+		exit(!__test_passed(_metadata));
 	}
 }
 
-- 
2.43.0

[RFC 3/7] selftests: kselftest_harness: use exit code to store skip and xfail

[Jakub Kicinski]

We always use skip / xfail with combination of exit_code being 0
(KSFT_PASS). This are just basic KSFT / KTAP semantics.
Store the right KSFT_* code in exit_code directly.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/kselftest_harness.h | 35 ++++++---------------
 1 file changed, 9 insertions(+), 26 deletions(-)

diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 70366864ffd9..6923cd7060fc 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -136,8 +136,7 @@
 		fprintf(TH_LOG_STREAM, "#      SKIP      %s\n", \
 			_metadata->results->reason); \
 	} \
-	_metadata->exit_code = KSFT_PASS; \
-	_metadata->skip = 1; \
+	_metadata->exit_code = KSFT_SKIP; \
 	_metadata->trigger = 0; \
 	statement; \
 } while (0)
@@ -163,8 +162,7 @@
 		fprintf(TH_LOG_STREAM, "#      XFAIL     %s\n", \
 			_metadata->results->reason); \
 	} \
-	_metadata->exit_code = KSFT_PASS; \
-	_metadata->xfail = 1; \
+	_metadata->exit_code = KSFT_XFAIL; \
 	_metadata->trigger = 0; \
 	statement; \
 } while (0)
@@ -416,7 +414,7 @@
 		if (setjmp(_metadata->env) == 0) { \
 			fixture_name##_setup(_metadata, &self, variant->data); \
 			/* Let setup failure terminate early. */ \
-			if (!__test_passed(_metadata) || _metadata->skip) \
+			if (_metadata->exit_code) \
 				return; \
 			_metadata->setup_completed = true; \
 			fixture_name##_##test_name(_metadata, &self, variant->data); \
@@ -861,8 +859,6 @@ struct __test_metadata {
 	struct __fixture_metadata *fixture;
 	int termsig;
 	int exit_code;
-	int skip;	/* did SKIP get used? */
-	int xfail;	/* did XFAIL get used? */
 	int trigger; /* extra handler after the evaluation */
 	int timeout;	/* seconds to wait for test timeout */
 	bool timed_out;	/* did this test timeout instead of exiting? */
@@ -972,13 +968,9 @@ void __wait_for_test(struct __test_metadata *t)
 		fprintf(TH_LOG_STREAM,
 			"# %s: Test terminated by timeout\n", t->name);
 	} else if (WIFEXITED(status)) {
-		if (WEXITSTATUS(status) == KSFT_SKIP) {
-			/* SKIP */
-			t->exit_code = KSFT_PASS;
-			t->skip = 1;
-		} else if (WEXITSTATUS(status) == KSFT_XFAIL) {
-			t->exit_code = KSFT_PASS;
-			t->xfail = 1;
+		if (WEXITSTATUS(status) == KSFT_SKIP ||
+		    WEXITSTATUS(status) == KSFT_XFAIL) {
+			t->exit_code = WEXITSTATUS(status);
 		} else if (t->termsig != -1) {
 			t->exit_code = KSFT_FAIL;
 			fprintf(TH_LOG_STREAM,
@@ -1151,8 +1143,6 @@ void __run_test(struct __fixture_metadata *f,
 
 	/* reset test struct */
 	t->exit_code = KSFT_PASS;
-	t->skip = 0;
-	t->xfail = 0;
 	t->trigger = 0;
 	t->no_print = 0;
 	memset(t->results->reason, 0, sizeof(t->results->reason));
@@ -1174,24 +1164,17 @@ void __run_test(struct __fixture_metadata *f,
 	} else if (t->pid == 0) {
 		setpgrp();
 		t->fn(t, variant);
-		if (t->skip)
-			_exit(KSFT_SKIP);
-		if (t->xfail)
-			_exit(KSFT_XFAIL);
-		if (__test_passed(t))
-			_exit(KSFT_PASS);
-		/* Something else happened. */
-		_exit(KSFT_FAIL);
+		_exit(t->exit_code);
 	} else {
 		__wait_for_test(t);
 	}
 	ksft_print_msg("         %4s  %s\n",
 		       __test_passed(t) ? "OK" : "FAIL", test_name);
 
-	if (t->skip)
+	if (t->exit_code == KSFT_SKIP)
 		ksft_test_result_skip("%s\n", t->results->reason[0] ?
 					t->results->reason : "unknown");
-	else if (t->xfail)
+	else if (t->exit_code == KSFT_XFAIL)
 		ksft_test_result_xfail("%s\n", t->results->reason[0] ?
 				       t->results->reason : "unknown");
 	else
-- 
2.43.0

[RFC 4/7] selftests: kselftest: add ksft_test_result_code(), handling all exit codes

[Jakub Kicinski]

For generic test harness code it's more useful to deal with exit
codes directly, rather than having to switch on them and call
the right ksft_test_result_*() helper. Add such function to kselftest.h.

Note that "directive" and "diagnostic" are what ktap docs call
those parts of the message.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/kselftest.h         | 39 +++++++++++++++++++++
 tools/testing/selftests/kselftest_harness.h | 14 ++++----
 2 files changed, 47 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/kselftest.h b/tools/testing/selftests/kselftest.h
index a781e6311810..12ad7f8dfe3a 100644
--- a/tools/testing/selftests/kselftest.h
+++ b/tools/testing/selftests/kselftest.h
@@ -25,6 +25,7 @@
  *     ksft_test_result_skip(fmt, ...);
  *     ksft_test_result_xfail(fmt, ...);
  *     ksft_test_result_error(fmt, ...);
+ *     ksft_test_result_code(exit_code, test_name, fmt, ...);
  *
  * When all tests are finished, clean up and exit the program with one of:
  *
@@ -254,6 +255,44 @@ static inline __printf(1, 2) void ksft_test_result_error(const char *msg, ...)
 	va_end(args);
 }
 
+static inline __printf(2, 3)
+void ksft_test_result_code(int exit_code, const char *msg, ...)
+{
+	const char *tap_code = "ok";
+	const char *directive = "";
+	int saved_errno = errno;
+	va_list args;
+
+	switch (exit_code) {
+	case KSFT_PASS:
+		ksft_cnt.ksft_pass++;
+		break;
+	case KSFT_XFAIL:
+		directive = " # XFAIL ";
+		ksft_cnt.ksft_xfail++;
+		break;
+	case KSFT_XPASS:
+		directive = " # XPASS ";
+		ksft_cnt.ksft_xpass++;
+		break;
+	case KSFT_SKIP:
+		directive = " # SKIP ";
+		ksft_cnt.ksft_xskip++;
+		break;
+	case KSFT_FAIL:
+	default:
+		tap_code = "not ok";
+		ksft_cnt.ksft_fail++;
+		break;
+	}
+
+	va_start(args, msg);
+	printf("%s %u%s", tap_code, ksft_test_num(), directive);
+	errno = saved_errno;
+	vprintf(msg, args);
+	va_end(args);
+}
+
 static inline int ksft_exit_pass(void)
 {
 	ksft_print_cnts();
diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 6923cd7060fc..79a3fec0cefa 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -1140,6 +1140,7 @@ void __run_test(struct __fixture_metadata *f,
 		struct __test_metadata *t)
 {
 	char test_name[LINE_MAX];
+	const char *diagnostic;
 
 	/* reset test struct */
 	t->exit_code = KSFT_PASS;
@@ -1171,12 +1172,13 @@ void __run_test(struct __fixture_metadata *f,
 	ksft_print_msg("         %4s  %s\n",
 		       __test_passed(t) ? "OK" : "FAIL", test_name);
 
-	if (t->exit_code == KSFT_SKIP)
-		ksft_test_result_skip("%s\n", t->results->reason[0] ?
-					t->results->reason : "unknown");
-	else if (t->exit_code == KSFT_XFAIL)
-		ksft_test_result_xfail("%s\n", t->results->reason[0] ?
-				       t->results->reason : "unknown");
+	if (t->results->reason[0])
+		diagnostic = t->results->reason;
+	else
+		diagnostic = "unknown";
+
+	if (t->exit_code == KSFT_SKIP || t->exit_code == KSFT_XFAIL)
+		ksft_test_result_code(t->exit_code, "%s\n", diagnostic);
 	else
 		ksft_test_result(__test_passed(t), "%s\n", test_name);
 }
-- 
2.43.0

[RFC 5/7] selftests: kselftest_harness: print test name for SKIP and XFAIL

[Jakub Kicinski]

Jakub points out that for parsers it's rather useful to always
have the test name on the result line. Currently if we SKIP
or XFAIL, we will print:

ok 17 # SKIP SCTP doesn't support IP_BIND_ADDRESS_NO_PORT

     ^
     no test name

Always print the test name.
KTAP format seems to allow or even call for it, per:
https://docs.kernel.org/dev-tools/ktap.html

Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/all/87jzn6lnou.fsf@cloudflare.com/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/kselftest.h         | 7 ++++---
 tools/testing/selftests/kselftest_harness.h | 3 ++-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kselftest.h b/tools/testing/selftests/kselftest.h
index 12ad7f8dfe3a..25e29626566e 100644
--- a/tools/testing/selftests/kselftest.h
+++ b/tools/testing/selftests/kselftest.h
@@ -255,8 +255,9 @@ static inline __printf(1, 2) void ksft_test_result_error(const char *msg, ...)
 	va_end(args);
 }
 
-static inline __printf(2, 3)
-void ksft_test_result_code(int exit_code, const char *msg, ...)
+static inline __printf(3, 4)
+void ksft_test_result_code(int exit_code, const char *test_name,
+			   const char *msg, ...)
 {
 	const char *tap_code = "ok";
 	const char *directive = "";
@@ -287,7 +288,7 @@ void ksft_test_result_code(int exit_code, const char *msg, ...)
 	}
 
 	va_start(args, msg);
-	printf("%s %u%s", tap_code, ksft_test_num(), directive);
+	printf("%s %u %s%s", tap_code, ksft_test_num(), test_name, directive);
 	errno = saved_errno;
 	vprintf(msg, args);
 	va_end(args);
diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 79a3fec0cefa..beae50fd5ac3 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -1178,7 +1178,8 @@ void __run_test(struct __fixture_metadata *f,
 		diagnostic = "unknown";
 
 	if (t->exit_code == KSFT_SKIP || t->exit_code == KSFT_XFAIL)
-		ksft_test_result_code(t->exit_code, "%s\n", diagnostic);
+		ksft_test_result_code(t->exit_code, test_name,
+				      "%s\n", diagnostic);
 	else
 		ksft_test_result(__test_passed(t), "%s\n", test_name);
 }
-- 
2.43.0

[RFC 6/7] selftests: kselftest_harness: let ksft_test_result_code() handle line termination

[Jakub Kicinski]

According to the spec we should always print a # if we add
a diagnostic message. Having the caller pass in the new line
as part of diagnostic message makes handling this a bit
counter-intuitive.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/kselftest.h         | 5 +++++
 tools/testing/selftests/kselftest_harness.h | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kselftest.h b/tools/testing/selftests/kselftest.h
index 25e29626566e..541bf192e30e 100644
--- a/tools/testing/selftests/kselftest.h
+++ b/tools/testing/selftests/kselftest.h
@@ -287,10 +287,15 @@ void ksft_test_result_code(int exit_code, const char *test_name,
 		break;
 	}
 
+	/* Docs seem to call for double space if directive is absent */
+	if (!directive[0] && msg[0])
+		directive = " #  ";
+
 	va_start(args, msg);
 	printf("%s %u %s%s", tap_code, ksft_test_num(), test_name, directive);
 	errno = saved_errno;
 	vprintf(msg, args);
+	printf("\n");
 	va_end(args);
 }
 
diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index beae50fd5ac3..5fca75e180b8 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -1179,7 +1179,7 @@ void __run_test(struct __fixture_metadata *f,
 
 	if (t->exit_code == KSFT_SKIP || t->exit_code == KSFT_XFAIL)
 		ksft_test_result_code(t->exit_code, test_name,
-				      "%s\n", diagnostic);
+				      "%s", diagnostic);
 	else
 		ksft_test_result(__test_passed(t), "%s\n", test_name);
 }
-- 
2.43.0

[RFC 7/7] selftests: kselftest_harness: let PASS / FAIL provide diagnostic

[Jakub Kicinski]

Switch to printing KTAP line for PASS / FAIL with ksft_test_result_code(),
this gives us the ability to report diagnostic messages for free.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/kselftest_harness.h | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 5fca75e180b8..202f599c1462 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -1174,14 +1174,12 @@ void __run_test(struct __fixture_metadata *f,
 
 	if (t->results->reason[0])
 		diagnostic = t->results->reason;
+	else if (t->exit_code == KSFT_PASS || t->exit_code == KSFT_FAIL)
+		diagnostic = "";
 	else
 		diagnostic = "unknown";
 
-	if (t->exit_code == KSFT_SKIP || t->exit_code == KSFT_XFAIL)
-		ksft_test_result_code(t->exit_code, test_name,
-				      "%s", diagnostic);
-	else
-		ksft_test_result(__test_passed(t), "%s\n", test_name);
+	ksft_test_result_code(t->exit_code, test_name, "%s", diagnostic);
 }
 
 static int test_harness_run(int argc, char **argv)
-- 
2.43.0

Re: [RFC 1/7] selftests: kselftest_harness: generate test name once

[Kees Cook]

On Thu, Feb 15, 2024 at 04:41:16PM -0800, Jakub Kicinski wrote:
> Since we added variant support generating full test case
> name takes 4 string arguments. We're about to need it
> in another two places. Stop the duplication and print
> once into a temporary buffer.
> 
> Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Clean refactoring -- makes this much more readable.

Acked-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook

Re: [RFC 0/7] selftests: kselftest_harness: use common result printing helper

[Kees Cook]

On Thu, Feb 15, 2024 at 04:41:15PM -0800, Jakub Kicinski wrote:
> First 3 patches rearrange kselftest_harness to use exit code
> as an enum rather than separate passed/skip/xfail members.

One thought I was having here while porting other stuff to use XFAIL was
that in the strictest sense, XFAIL isn't like SKIP, which can be used to
avoid running a test entirely. XFAIL is about the expected outcome,
which means that if we're going to support XFAIL correctly, we need to
distinguish when a test was marked XFAIL but it _didn't_ fail.

The implicit expectation is that a test outcome should be "pass". If
something is marked "xfail", we're saying a successful test is that it
fails. If it _passes_ instead of failing, this is unexpected and should
be reported as well. (i.e. an XPASS -- unexpected pass)

I think if we mix intent with result code, we're going to lose the
ability to make this distinction in the future. (Right now the harness
doesn't do it either -- it treats XFAIL as a special SKIP.)

-- 
Kees Cook

Re: [RFC 0/7] selftests: kselftest_harness: use common result printing helper

[Jakub Kicinski]

On Fri, 16 Feb 2024 13:32:12 -0800 Kees Cook wrote:
> On Thu, Feb 15, 2024 at 04:41:15PM -0800, Jakub Kicinski wrote:
> > First 3 patches rearrange kselftest_harness to use exit code
> > as an enum rather than separate passed/skip/xfail members.  
> 
> One thought I was having here while porting other stuff to use XFAIL was
> that in the strictest sense, XFAIL isn't like SKIP, which can be used to
> avoid running a test entirely. XFAIL is about the expected outcome,
> which means that if we're going to support XFAIL correctly, we need to
> distinguish when a test was marked XFAIL but it _didn't_ fail.
> 
> The implicit expectation is that a test outcome should be "pass". If
> something is marked "xfail", we're saying a successful test is that it
> fails. If it _passes_ instead of failing, this is unexpected and should
> be reported as well. (i.e. an XPASS -- unexpected pass)
> 
> I think if we mix intent with result code, we're going to lose the
> ability to make this distinction in the future. (Right now the harness
> doesn't do it either -- it treats XFAIL as a special SKIP.)

Hm.

Let's call "case" the combination of fixture + variant + test.
Currently nothing identifies a single "case" in the harness.
We just recursively walk dimensions.

We can add a new registration list and let user register expected
failures. It should work nicely as long as the exceptions are very
rare. Which is hopefully the case.

Let's see if I can code this up in 30 min. While I do that can you 
ELI5 what XPASS is for?! We'll never going to use it, right?

Re: [RFC 0/7] selftests: kselftest_harness: use common result printing helper

[Jakub Kicinski]

On Fri, 16 Feb 2024 16:31:19 -0800 Jakub Kicinski wrote:
> Let's see if I can code this up in 30 min. While I do that can you 
> ELI5 what XPASS is for?! We'll never going to use it, right?

Oh, it's UNexpected pass. Okay. So if we have a case on a list of
expected failures and it passes we should throw xpass.

Re: [RFC 0/7] selftests: kselftest_harness: use common result printing helper

[Jakub Kicinski]

On Fri, 16 Feb 2024 16:33:04 -0800 Jakub Kicinski wrote:
> On Fri, 16 Feb 2024 16:31:19 -0800 Jakub Kicinski wrote:
> > Let's see if I can code this up in 30 min. While I do that can you 
> > ELI5 what XPASS is for?! We'll never going to use it, right?  
> 
> Oh, it's UNexpected pass. Okay. So if we have a case on a list of
> expected failures and it passes we should throw xpass.

I got distracted from this distraction :S
Is this along the lines of what you had in mind?
Both my series need to be rejigged to change the paradigm 
but as a PoC on top of them:

diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 202f599c1462..399a200a1160 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -826,6 +826,27 @@ struct __fixture_metadata {
 	.prev = &_fixture_global,
 };
 
+struct __test_xfail {
+	struct __fixture_metadata *fixture;
+	struct __fixture_variant_metadata *variant;
+	struct __test_metadata *test;
+	struct __test_xfail *prev, *next;
+};
+
+#define XFAIL_ADD(fixture_name, variant_name, test_name)    \
+	\
+	static struct __test_xfail \
+		_##fixture_name##_##variant_name##_##test_name##_xfail = \
+		{ .fixture = &_##fixture_name##_fixture_object, \
+		  .variant = &_##fixture_name##_##variant_name##_object, \
+		  .test = &_##fixture_name##_##test_name##_object,	\
+		  };\
+	static void __attribute__((constructor))		\
+		_register_##fixture_name##_##variant_name##_##test_name##_xfail(void) \
+	{ \
+		__register_xfail(&_##fixture_name##_##variant_name##_##test_name##_xfail);	\
+	}
+
 static struct __fixture_metadata *__fixture_list = &_fixture_global;
 static int __constructor_order;
 
@@ -840,6 +861,7 @@ static inline void __register_fixture(struct __fixture_metadata *f)
 struct __fixture_variant_metadata {
 	const char *name;
 	const void *data;
+	struct __test_xfail *xfails;
 	struct __fixture_variant_metadata *prev, *next;
 };
 
@@ -890,6 +912,11 @@ static inline void __register_test(struct __test_metadata *t)
 	__LIST_APPEND(t->fixture->tests, t);
 }
 
+static inline void __register_xfail(struct __test_xfail *xf)
+{
+	__LIST_APPEND(xf->variant->xfails, xf);
+}
+
 static inline int __bail(int for_realz, struct __test_metadata *t)
 {
 	/* if this is ASSERT, return immediately. */
@@ -1139,6 +1166,7 @@ void __run_test(struct __fixture_metadata *f,
 		struct __fixture_variant_metadata *variant,
 		struct __test_metadata *t)
 {
+	struct __test_xfail *xfail;
 	char test_name[LINE_MAX];
 	const char *diagnostic;
 
@@ -1172,6 +1200,14 @@ void __run_test(struct __fixture_metadata *f,
 	ksft_print_msg("         %4s  %s\n",
 		       __test_passed(t) ? "OK" : "FAIL", test_name);
 
+	/* Check if we're expecting this test to fail */
+	for (xfail = variant->xfails; xfail; xfail = xfail->next)
+		if (xfail->test == t)
+			break;
+	if (xfail)
+		t->exit_code = __test_passed(t) ? KSFT_XPASS : KSFT_XFAIL;
+
+
 	if (t->results->reason[0])
 		diagnostic = t->results->reason;
 	else if (t->exit_code == KSFT_PASS || t->exit_code == KSFT_FAIL)
diff --git a/tools/testing/selftests/net/ip_local_port_range.c b/tools/testing/selftests/net/ip_local_port_range.c
index d4f789f524e5..242ff7de1b12 100644
--- a/tools/testing/selftests/net/ip_local_port_range.c
+++ b/tools/testing/selftests/net/ip_local_port_range.c
@@ -414,6 +414,9 @@ TEST_F(ip_local_port_range, late_bind)
 	ASSERT_TRUE(!err) TH_LOG("close failed");
 }
 
+XFAIL_ADD(ip_local_port_range, ip4_stcp, late_bind);
+XFAIL_ADD(ip_local_port_range, ip6_stcp, late_bind);
+
 TEST_F(ip_local_port_range, get_port_range)
 {
 	__u16 lo, hi;

Re: [RFC 0/7] selftests: kselftest_harness: use common result printing helper

[Kees Cook]

On February 16, 2024 5:26:21 PM PST, Jakub Kicinski <kuba@kernel.org> wrote:
>On Fri, 16 Feb 2024 16:33:04 -0800 Jakub Kicinski wrote:
>> On Fri, 16 Feb 2024 16:31:19 -0800 Jakub Kicinski wrote:
>> > Let's see if I can code this up in 30 min. While I do that can you 
>> > ELI5 what XPASS is for?! We'll never going to use it, right?  
>> 
>> Oh, it's UNexpected pass. Okay. So if we have a case on a list of
>> expected failures and it passes we should throw xpass.

Right: it's still "ok" but it identifies something worth looking at ("why did this start passing?")

>
>I got distracted from this distraction :S
>Is this along the lines of what you had in mind?
>Both my series need to be rejigged to change the paradigm 
>but as a PoC on top of them:

Oh yeah! This looks good. I will give it a spin tomorrow.

-Kees

-- 
Kees Cook