xref: /linux/lib/kunit/test.c (revision 83439a0f1ce6a592f95e41338320b5f01b98a356)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Base unit test (KUnit) API.
4  *
5  * Copyright (C) 2019, Google LLC.
6  * Author: Brendan Higgins <brendanhiggins@google.com>
7  */
8 
9 #include <kunit/resource.h>
10 #include <kunit/test.h>
11 #include <kunit/test-bug.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/panic.h>
16 #include <linux/sched/debug.h>
17 #include <linux/sched.h>
18 
19 #include "debugfs.h"
20 #include "string-stream.h"
21 #include "try-catch-impl.h"
22 
23 #if IS_BUILTIN(CONFIG_KUNIT)
24 /*
25  * Fail the current test and print an error message to the log.
26  */
27 void __kunit_fail_current_test(const char *file, int line, const char *fmt, ...)
28 {
29 	va_list args;
30 	int len;
31 	char *buffer;
32 
33 	if (!current->kunit_test)
34 		return;
35 
36 	kunit_set_failure(current->kunit_test);
37 
38 	/* kunit_err() only accepts literals, so evaluate the args first. */
39 	va_start(args, fmt);
40 	len = vsnprintf(NULL, 0, fmt, args) + 1;
41 	va_end(args);
42 
43 	buffer = kunit_kmalloc(current->kunit_test, len, GFP_KERNEL);
44 	if (!buffer)
45 		return;
46 
47 	va_start(args, fmt);
48 	vsnprintf(buffer, len, fmt, args);
49 	va_end(args);
50 
51 	kunit_err(current->kunit_test, "%s:%d: %s", file, line, buffer);
52 	kunit_kfree(current->kunit_test, buffer);
53 }
54 EXPORT_SYMBOL_GPL(__kunit_fail_current_test);
55 #endif
56 
57 /*
58  * Enable KUnit tests to run.
59  */
60 #ifdef CONFIG_KUNIT_DEFAULT_ENABLED
61 static bool enable_param = true;
62 #else
63 static bool enable_param;
64 #endif
65 module_param_named(enable, enable_param, bool, 0);
66 MODULE_PARM_DESC(enable, "Enable KUnit tests");
67 
68 /*
69  * KUnit statistic mode:
70  * 0 - disabled
71  * 1 - only when there is more than one subtest
72  * 2 - enabled
73  */
74 static int kunit_stats_enabled = 1;
75 module_param_named(stats_enabled, kunit_stats_enabled, int, 0644);
76 MODULE_PARM_DESC(stats_enabled,
77 		  "Print test stats: never (0), only for multiple subtests (1), or always (2)");
78 
79 struct kunit_result_stats {
80 	unsigned long passed;
81 	unsigned long skipped;
82 	unsigned long failed;
83 	unsigned long total;
84 };
85 
86 static bool kunit_should_print_stats(struct kunit_result_stats stats)
87 {
88 	if (kunit_stats_enabled == 0)
89 		return false;
90 
91 	if (kunit_stats_enabled == 2)
92 		return true;
93 
94 	return (stats.total > 1);
95 }
96 
97 static void kunit_print_test_stats(struct kunit *test,
98 				   struct kunit_result_stats stats)
99 {
100 	if (!kunit_should_print_stats(stats))
101 		return;
102 
103 	kunit_log(KERN_INFO, test,
104 		  KUNIT_SUBTEST_INDENT
105 		  "# %s: pass:%lu fail:%lu skip:%lu total:%lu",
106 		  test->name,
107 		  stats.passed,
108 		  stats.failed,
109 		  stats.skipped,
110 		  stats.total);
111 }
112 
113 /*
114  * Append formatted message to log, size of which is limited to
115  * KUNIT_LOG_SIZE bytes (including null terminating byte).
116  */
117 void kunit_log_append(char *log, const char *fmt, ...)
118 {
119 	char line[KUNIT_LOG_SIZE];
120 	va_list args;
121 	int len_left;
122 
123 	if (!log)
124 		return;
125 
126 	len_left = KUNIT_LOG_SIZE - strlen(log) - 1;
127 	if (len_left <= 0)
128 		return;
129 
130 	va_start(args, fmt);
131 	vsnprintf(line, sizeof(line), fmt, args);
132 	va_end(args);
133 
134 	strncat(log, line, len_left);
135 }
136 EXPORT_SYMBOL_GPL(kunit_log_append);
137 
138 size_t kunit_suite_num_test_cases(struct kunit_suite *suite)
139 {
140 	struct kunit_case *test_case;
141 	size_t len = 0;
142 
143 	kunit_suite_for_each_test_case(suite, test_case)
144 		len++;
145 
146 	return len;
147 }
148 EXPORT_SYMBOL_GPL(kunit_suite_num_test_cases);
149 
150 static void kunit_print_suite_start(struct kunit_suite *suite)
151 {
152 	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "# Subtest: %s",
153 		  suite->name);
154 	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "1..%zd",
155 		  kunit_suite_num_test_cases(suite));
156 }
157 
158 static void kunit_print_ok_not_ok(void *test_or_suite,
159 				  bool is_test,
160 				  enum kunit_status status,
161 				  size_t test_number,
162 				  const char *description,
163 				  const char *directive)
164 {
165 	struct kunit_suite *suite = is_test ? NULL : test_or_suite;
166 	struct kunit *test = is_test ? test_or_suite : NULL;
167 	const char *directive_header = (status == KUNIT_SKIPPED) ? " # SKIP " : "";
168 
169 	/*
170 	 * We do not log the test suite results as doing so would
171 	 * mean debugfs display would consist of the test suite
172 	 * description and status prior to individual test results.
173 	 * Hence directly printk the suite status, and we will
174 	 * separately seq_printf() the suite status for the debugfs
175 	 * representation.
176 	 */
177 	if (suite)
178 		pr_info("%s %zd - %s%s%s\n",
179 			kunit_status_to_ok_not_ok(status),
180 			test_number, description, directive_header,
181 			(status == KUNIT_SKIPPED) ? directive : "");
182 	else
183 		kunit_log(KERN_INFO, test,
184 			  KUNIT_SUBTEST_INDENT "%s %zd - %s%s%s",
185 			  kunit_status_to_ok_not_ok(status),
186 			  test_number, description, directive_header,
187 			  (status == KUNIT_SKIPPED) ? directive : "");
188 }
189 
190 enum kunit_status kunit_suite_has_succeeded(struct kunit_suite *suite)
191 {
192 	const struct kunit_case *test_case;
193 	enum kunit_status status = KUNIT_SKIPPED;
194 
195 	if (suite->suite_init_err)
196 		return KUNIT_FAILURE;
197 
198 	kunit_suite_for_each_test_case(suite, test_case) {
199 		if (test_case->status == KUNIT_FAILURE)
200 			return KUNIT_FAILURE;
201 		else if (test_case->status == KUNIT_SUCCESS)
202 			status = KUNIT_SUCCESS;
203 	}
204 
205 	return status;
206 }
207 EXPORT_SYMBOL_GPL(kunit_suite_has_succeeded);
208 
209 static size_t kunit_suite_counter = 1;
210 
211 static void kunit_print_suite_end(struct kunit_suite *suite)
212 {
213 	kunit_print_ok_not_ok((void *)suite, false,
214 			      kunit_suite_has_succeeded(suite),
215 			      kunit_suite_counter++,
216 			      suite->name,
217 			      suite->status_comment);
218 }
219 
220 unsigned int kunit_test_case_num(struct kunit_suite *suite,
221 				 struct kunit_case *test_case)
222 {
223 	struct kunit_case *tc;
224 	unsigned int i = 1;
225 
226 	kunit_suite_for_each_test_case(suite, tc) {
227 		if (tc == test_case)
228 			return i;
229 		i++;
230 	}
231 
232 	return 0;
233 }
234 EXPORT_SYMBOL_GPL(kunit_test_case_num);
235 
236 static void kunit_print_string_stream(struct kunit *test,
237 				      struct string_stream *stream)
238 {
239 	struct string_stream_fragment *fragment;
240 	char *buf;
241 
242 	if (string_stream_is_empty(stream))
243 		return;
244 
245 	buf = string_stream_get_string(stream);
246 	if (!buf) {
247 		kunit_err(test,
248 			  "Could not allocate buffer, dumping stream:\n");
249 		list_for_each_entry(fragment, &stream->fragments, node) {
250 			kunit_err(test, "%s", fragment->fragment);
251 		}
252 		kunit_err(test, "\n");
253 	} else {
254 		kunit_err(test, "%s", buf);
255 		kunit_kfree(test, buf);
256 	}
257 }
258 
259 static void kunit_fail(struct kunit *test, const struct kunit_loc *loc,
260 		       enum kunit_assert_type type, const struct kunit_assert *assert,
261 		       const struct va_format *message)
262 {
263 	struct string_stream *stream;
264 
265 	kunit_set_failure(test);
266 
267 	stream = alloc_string_stream(test, GFP_KERNEL);
268 	if (!stream) {
269 		WARN(true,
270 		     "Could not allocate stream to print failed assertion in %s:%d\n",
271 		     loc->file,
272 		     loc->line);
273 		return;
274 	}
275 
276 	kunit_assert_prologue(loc, type, stream);
277 	assert->format(assert, message, stream);
278 
279 	kunit_print_string_stream(test, stream);
280 
281 	WARN_ON(string_stream_destroy(stream));
282 }
283 
284 static void __noreturn kunit_abort(struct kunit *test)
285 {
286 	kunit_try_catch_throw(&test->try_catch); /* Does not return. */
287 
288 	/*
289 	 * Throw could not abort from test.
290 	 *
291 	 * XXX: we should never reach this line! As kunit_try_catch_throw is
292 	 * marked __noreturn.
293 	 */
294 	WARN_ONCE(true, "Throw could not abort from test!\n");
295 }
296 
297 void kunit_do_failed_assertion(struct kunit *test,
298 			       const struct kunit_loc *loc,
299 			       enum kunit_assert_type type,
300 			       const struct kunit_assert *assert,
301 			       const char *fmt, ...)
302 {
303 	va_list args;
304 	struct va_format message;
305 	va_start(args, fmt);
306 
307 	message.fmt = fmt;
308 	message.va = &args;
309 
310 	kunit_fail(test, loc, type, assert, &message);
311 
312 	va_end(args);
313 
314 	if (type == KUNIT_ASSERTION)
315 		kunit_abort(test);
316 }
317 EXPORT_SYMBOL_GPL(kunit_do_failed_assertion);
318 
319 void kunit_init_test(struct kunit *test, const char *name, char *log)
320 {
321 	spin_lock_init(&test->lock);
322 	INIT_LIST_HEAD(&test->resources);
323 	test->name = name;
324 	test->log = log;
325 	if (test->log)
326 		test->log[0] = '\0';
327 	test->status = KUNIT_SUCCESS;
328 	test->status_comment[0] = '\0';
329 }
330 EXPORT_SYMBOL_GPL(kunit_init_test);
331 
332 /*
333  * Initializes and runs test case. Does not clean up or do post validations.
334  */
335 static void kunit_run_case_internal(struct kunit *test,
336 				    struct kunit_suite *suite,
337 				    struct kunit_case *test_case)
338 {
339 	if (suite->init) {
340 		int ret;
341 
342 		ret = suite->init(test);
343 		if (ret) {
344 			kunit_err(test, "failed to initialize: %d\n", ret);
345 			kunit_set_failure(test);
346 			return;
347 		}
348 	}
349 
350 	test_case->run_case(test);
351 }
352 
353 static void kunit_case_internal_cleanup(struct kunit *test)
354 {
355 	kunit_cleanup(test);
356 }
357 
358 /*
359  * Performs post validations and cleanup after a test case was run.
360  * XXX: Should ONLY BE CALLED AFTER kunit_run_case_internal!
361  */
362 static void kunit_run_case_cleanup(struct kunit *test,
363 				   struct kunit_suite *suite)
364 {
365 	if (suite->exit)
366 		suite->exit(test);
367 
368 	kunit_case_internal_cleanup(test);
369 }
370 
371 struct kunit_try_catch_context {
372 	struct kunit *test;
373 	struct kunit_suite *suite;
374 	struct kunit_case *test_case;
375 };
376 
377 static void kunit_try_run_case(void *data)
378 {
379 	struct kunit_try_catch_context *ctx = data;
380 	struct kunit *test = ctx->test;
381 	struct kunit_suite *suite = ctx->suite;
382 	struct kunit_case *test_case = ctx->test_case;
383 
384 	current->kunit_test = test;
385 
386 	/*
387 	 * kunit_run_case_internal may encounter a fatal error; if it does,
388 	 * abort will be called, this thread will exit, and finally the parent
389 	 * thread will resume control and handle any necessary clean up.
390 	 */
391 	kunit_run_case_internal(test, suite, test_case);
392 	/* This line may never be reached. */
393 	kunit_run_case_cleanup(test, suite);
394 }
395 
396 static void kunit_catch_run_case(void *data)
397 {
398 	struct kunit_try_catch_context *ctx = data;
399 	struct kunit *test = ctx->test;
400 	struct kunit_suite *suite = ctx->suite;
401 	int try_exit_code = kunit_try_catch_get_result(&test->try_catch);
402 
403 	if (try_exit_code) {
404 		kunit_set_failure(test);
405 		/*
406 		 * Test case could not finish, we have no idea what state it is
407 		 * in, so don't do clean up.
408 		 */
409 		if (try_exit_code == -ETIMEDOUT) {
410 			kunit_err(test, "test case timed out\n");
411 		/*
412 		 * Unknown internal error occurred preventing test case from
413 		 * running, so there is nothing to clean up.
414 		 */
415 		} else {
416 			kunit_err(test, "internal error occurred preventing test case from running: %d\n",
417 				  try_exit_code);
418 		}
419 		return;
420 	}
421 
422 	/*
423 	 * Test case was run, but aborted. It is the test case's business as to
424 	 * whether it failed or not, we just need to clean up.
425 	 */
426 	kunit_run_case_cleanup(test, suite);
427 }
428 
429 /*
430  * Performs all logic to run a test case. It also catches most errors that
431  * occur in a test case and reports them as failures.
432  */
433 static void kunit_run_case_catch_errors(struct kunit_suite *suite,
434 					struct kunit_case *test_case,
435 					struct kunit *test)
436 {
437 	struct kunit_try_catch_context context;
438 	struct kunit_try_catch *try_catch;
439 
440 	kunit_init_test(test, test_case->name, test_case->log);
441 	try_catch = &test->try_catch;
442 
443 	kunit_try_catch_init(try_catch,
444 			     test,
445 			     kunit_try_run_case,
446 			     kunit_catch_run_case);
447 	context.test = test;
448 	context.suite = suite;
449 	context.test_case = test_case;
450 	kunit_try_catch_run(try_catch, &context);
451 
452 	/* Propagate the parameter result to the test case. */
453 	if (test->status == KUNIT_FAILURE)
454 		test_case->status = KUNIT_FAILURE;
455 	else if (test_case->status != KUNIT_FAILURE && test->status == KUNIT_SUCCESS)
456 		test_case->status = KUNIT_SUCCESS;
457 }
458 
459 static void kunit_print_suite_stats(struct kunit_suite *suite,
460 				    struct kunit_result_stats suite_stats,
461 				    struct kunit_result_stats param_stats)
462 {
463 	if (kunit_should_print_stats(suite_stats)) {
464 		kunit_log(KERN_INFO, suite,
465 			  "# %s: pass:%lu fail:%lu skip:%lu total:%lu",
466 			  suite->name,
467 			  suite_stats.passed,
468 			  suite_stats.failed,
469 			  suite_stats.skipped,
470 			  suite_stats.total);
471 	}
472 
473 	if (kunit_should_print_stats(param_stats)) {
474 		kunit_log(KERN_INFO, suite,
475 			  "# Totals: pass:%lu fail:%lu skip:%lu total:%lu",
476 			  param_stats.passed,
477 			  param_stats.failed,
478 			  param_stats.skipped,
479 			  param_stats.total);
480 	}
481 }
482 
483 static void kunit_update_stats(struct kunit_result_stats *stats,
484 			       enum kunit_status status)
485 {
486 	switch (status) {
487 	case KUNIT_SUCCESS:
488 		stats->passed++;
489 		break;
490 	case KUNIT_SKIPPED:
491 		stats->skipped++;
492 		break;
493 	case KUNIT_FAILURE:
494 		stats->failed++;
495 		break;
496 	}
497 
498 	stats->total++;
499 }
500 
501 static void kunit_accumulate_stats(struct kunit_result_stats *total,
502 				   struct kunit_result_stats add)
503 {
504 	total->passed += add.passed;
505 	total->skipped += add.skipped;
506 	total->failed += add.failed;
507 	total->total += add.total;
508 }
509 
510 int kunit_run_tests(struct kunit_suite *suite)
511 {
512 	char param_desc[KUNIT_PARAM_DESC_SIZE];
513 	struct kunit_case *test_case;
514 	struct kunit_result_stats suite_stats = { 0 };
515 	struct kunit_result_stats total_stats = { 0 };
516 
517 	/* Taint the kernel so we know we've run tests. */
518 	add_taint(TAINT_TEST, LOCKDEP_STILL_OK);
519 
520 	if (suite->suite_init) {
521 		suite->suite_init_err = suite->suite_init(suite);
522 		if (suite->suite_init_err) {
523 			kunit_err(suite, KUNIT_SUBTEST_INDENT
524 				  "# failed to initialize (%d)", suite->suite_init_err);
525 			goto suite_end;
526 		}
527 	}
528 
529 	kunit_print_suite_start(suite);
530 
531 	kunit_suite_for_each_test_case(suite, test_case) {
532 		struct kunit test = { .param_value = NULL, .param_index = 0 };
533 		struct kunit_result_stats param_stats = { 0 };
534 		test_case->status = KUNIT_SKIPPED;
535 
536 		if (!test_case->generate_params) {
537 			/* Non-parameterised test. */
538 			kunit_run_case_catch_errors(suite, test_case, &test);
539 			kunit_update_stats(&param_stats, test.status);
540 		} else {
541 			/* Get initial param. */
542 			param_desc[0] = '\0';
543 			test.param_value = test_case->generate_params(NULL, param_desc);
544 			kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT
545 				  "# Subtest: %s", test_case->name);
546 
547 			while (test.param_value) {
548 				kunit_run_case_catch_errors(suite, test_case, &test);
549 
550 				if (param_desc[0] == '\0') {
551 					snprintf(param_desc, sizeof(param_desc),
552 						 "param-%d", test.param_index);
553 				}
554 
555 				kunit_log(KERN_INFO, &test,
556 					  KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT
557 					  "%s %d - %s",
558 					  kunit_status_to_ok_not_ok(test.status),
559 					  test.param_index + 1, param_desc);
560 
561 				/* Get next param. */
562 				param_desc[0] = '\0';
563 				test.param_value = test_case->generate_params(test.param_value, param_desc);
564 				test.param_index++;
565 
566 				kunit_update_stats(&param_stats, test.status);
567 			}
568 		}
569 
570 
571 		kunit_print_test_stats(&test, param_stats);
572 
573 		kunit_print_ok_not_ok(&test, true, test_case->status,
574 				      kunit_test_case_num(suite, test_case),
575 				      test_case->name,
576 				      test.status_comment);
577 
578 		kunit_update_stats(&suite_stats, test_case->status);
579 		kunit_accumulate_stats(&total_stats, param_stats);
580 	}
581 
582 	if (suite->suite_exit)
583 		suite->suite_exit(suite);
584 
585 	kunit_print_suite_stats(suite, suite_stats, total_stats);
586 suite_end:
587 	kunit_print_suite_end(suite);
588 
589 	return 0;
590 }
591 EXPORT_SYMBOL_GPL(kunit_run_tests);
592 
593 static void kunit_init_suite(struct kunit_suite *suite)
594 {
595 	kunit_debugfs_create_suite(suite);
596 	suite->status_comment[0] = '\0';
597 	suite->suite_init_err = 0;
598 }
599 
600 bool kunit_enabled(void)
601 {
602 	return enable_param;
603 }
604 
605 int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_suites)
606 {
607 	unsigned int i;
608 
609 	if (!kunit_enabled() && num_suites > 0) {
610 		pr_info("kunit: disabled\n");
611 		return 0;
612 	}
613 
614 	for (i = 0; i < num_suites; i++) {
615 		kunit_init_suite(suites[i]);
616 		kunit_run_tests(suites[i]);
617 	}
618 	return 0;
619 }
620 EXPORT_SYMBOL_GPL(__kunit_test_suites_init);
621 
622 static void kunit_exit_suite(struct kunit_suite *suite)
623 {
624 	kunit_debugfs_destroy_suite(suite);
625 }
626 
627 void __kunit_test_suites_exit(struct kunit_suite **suites, int num_suites)
628 {
629 	unsigned int i;
630 
631 	if (!kunit_enabled())
632 		return;
633 
634 	for (i = 0; i < num_suites; i++)
635 		kunit_exit_suite(suites[i]);
636 
637 	kunit_suite_counter = 1;
638 }
639 EXPORT_SYMBOL_GPL(__kunit_test_suites_exit);
640 
641 #ifdef CONFIG_MODULES
642 static void kunit_module_init(struct module *mod)
643 {
644 	__kunit_test_suites_init(mod->kunit_suites, mod->num_kunit_suites);
645 }
646 
647 static void kunit_module_exit(struct module *mod)
648 {
649 	__kunit_test_suites_exit(mod->kunit_suites, mod->num_kunit_suites);
650 }
651 
652 static int kunit_module_notify(struct notifier_block *nb, unsigned long val,
653 			       void *data)
654 {
655 	struct module *mod = data;
656 
657 	switch (val) {
658 	case MODULE_STATE_LIVE:
659 		kunit_module_init(mod);
660 		break;
661 	case MODULE_STATE_GOING:
662 		kunit_module_exit(mod);
663 		break;
664 	case MODULE_STATE_COMING:
665 	case MODULE_STATE_UNFORMED:
666 		break;
667 	}
668 
669 	return 0;
670 }
671 
672 static struct notifier_block kunit_mod_nb = {
673 	.notifier_call = kunit_module_notify,
674 	.priority = 0,
675 };
676 #endif
677 
678 struct kunit_kmalloc_array_params {
679 	size_t n;
680 	size_t size;
681 	gfp_t gfp;
682 };
683 
684 static int kunit_kmalloc_array_init(struct kunit_resource *res, void *context)
685 {
686 	struct kunit_kmalloc_array_params *params = context;
687 
688 	res->data = kmalloc_array(params->n, params->size, params->gfp);
689 	if (!res->data)
690 		return -ENOMEM;
691 
692 	return 0;
693 }
694 
695 static void kunit_kmalloc_array_free(struct kunit_resource *res)
696 {
697 	kfree(res->data);
698 }
699 
700 void *kunit_kmalloc_array(struct kunit *test, size_t n, size_t size, gfp_t gfp)
701 {
702 	struct kunit_kmalloc_array_params params = {
703 		.size = size,
704 		.n = n,
705 		.gfp = gfp
706 	};
707 
708 	return kunit_alloc_resource(test,
709 				    kunit_kmalloc_array_init,
710 				    kunit_kmalloc_array_free,
711 				    gfp,
712 				    &params);
713 }
714 EXPORT_SYMBOL_GPL(kunit_kmalloc_array);
715 
716 void kunit_kfree(struct kunit *test, const void *ptr)
717 {
718 	struct kunit_resource *res;
719 
720 	res = kunit_find_resource(test, kunit_resource_instance_match,
721 				  (void *)ptr);
722 
723 	/*
724 	 * Removing the resource from the list of resources drops the
725 	 * reference count to 1; the final put will trigger the free.
726 	 */
727 	kunit_remove_resource(test, res);
728 
729 	kunit_put_resource(res);
730 
731 }
732 EXPORT_SYMBOL_GPL(kunit_kfree);
733 
734 void kunit_cleanup(struct kunit *test)
735 {
736 	struct kunit_resource *res;
737 	unsigned long flags;
738 
739 	/*
740 	 * test->resources is a stack - each allocation must be freed in the
741 	 * reverse order from which it was added since one resource may depend
742 	 * on another for its entire lifetime.
743 	 * Also, we cannot use the normal list_for_each constructs, even the
744 	 * safe ones because *arbitrary* nodes may be deleted when
745 	 * kunit_resource_free is called; the list_for_each_safe variants only
746 	 * protect against the current node being deleted, not the next.
747 	 */
748 	while (true) {
749 		spin_lock_irqsave(&test->lock, flags);
750 		if (list_empty(&test->resources)) {
751 			spin_unlock_irqrestore(&test->lock, flags);
752 			break;
753 		}
754 		res = list_last_entry(&test->resources,
755 				      struct kunit_resource,
756 				      node);
757 		/*
758 		 * Need to unlock here as a resource may remove another
759 		 * resource, and this can't happen if the test->lock
760 		 * is held.
761 		 */
762 		spin_unlock_irqrestore(&test->lock, flags);
763 		kunit_remove_resource(test, res);
764 	}
765 	current->kunit_test = NULL;
766 }
767 EXPORT_SYMBOL_GPL(kunit_cleanup);
768 
769 static int __init kunit_init(void)
770 {
771 	kunit_debugfs_init();
772 #ifdef CONFIG_MODULES
773 	return register_module_notifier(&kunit_mod_nb);
774 #else
775 	return 0;
776 #endif
777 }
778 late_initcall(kunit_init);
779 
780 static void __exit kunit_exit(void)
781 {
782 #ifdef CONFIG_MODULES
783 	unregister_module_notifier(&kunit_mod_nb);
784 #endif
785 	kunit_debugfs_cleanup();
786 }
787 module_exit(kunit_exit);
788 
789 MODULE_LICENSE("GPL v2");
790