xref: /openbmc/linux/lib/kunit/test.c (revision b9ddb2500e7e544410f38476ab928fc2fe01e381)
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/test.h>
10  #include <linux/kernel.h>
11  #include <linux/kref.h>
12  #include <linux/sched/debug.h>
13  #include <linux/sched.h>
14  
15  #include "debugfs.h"
16  #include "string-stream.h"
17  #include "try-catch-impl.h"
18  
19  /*
20   * Append formatted message to log, size of which is limited to
21   * KUNIT_LOG_SIZE bytes (including null terminating byte).
22   */
23  void kunit_log_append(char *log, const char *fmt, ...)
24  {
25  	char line[KUNIT_LOG_SIZE];
26  	va_list args;
27  	int len_left;
28  
29  	if (!log)
30  		return;
31  
32  	len_left = KUNIT_LOG_SIZE - strlen(log) - 1;
33  	if (len_left <= 0)
34  		return;
35  
36  	va_start(args, fmt);
37  	vsnprintf(line, sizeof(line), fmt, args);
38  	va_end(args);
39  
40  	strncat(log, line, len_left);
41  }
42  EXPORT_SYMBOL_GPL(kunit_log_append);
43  
44  size_t kunit_suite_num_test_cases(struct kunit_suite *suite)
45  {
46  	struct kunit_case *test_case;
47  	size_t len = 0;
48  
49  	kunit_suite_for_each_test_case(suite, test_case)
50  		len++;
51  
52  	return len;
53  }
54  EXPORT_SYMBOL_GPL(kunit_suite_num_test_cases);
55  
56  static void kunit_print_subtest_start(struct kunit_suite *suite)
57  {
58  	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "# Subtest: %s",
59  		  suite->name);
60  	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "1..%zd",
61  		  kunit_suite_num_test_cases(suite));
62  }
63  
64  static void kunit_print_ok_not_ok(void *test_or_suite,
65  				  bool is_test,
66  				  bool is_ok,
67  				  size_t test_number,
68  				  const char *description)
69  {
70  	struct kunit_suite *suite = is_test ? NULL : test_or_suite;
71  	struct kunit *test = is_test ? test_or_suite : NULL;
72  
73  	/*
74  	 * We do not log the test suite results as doing so would
75  	 * mean debugfs display would consist of the test suite
76  	 * description and status prior to individual test results.
77  	 * Hence directly printk the suite status, and we will
78  	 * separately seq_printf() the suite status for the debugfs
79  	 * representation.
80  	 */
81  	if (suite)
82  		pr_info("%s %zd - %s\n",
83  			kunit_status_to_string(is_ok),
84  			test_number, description);
85  	else
86  		kunit_log(KERN_INFO, test, KUNIT_SUBTEST_INDENT "%s %zd - %s",
87  			  kunit_status_to_string(is_ok),
88  			  test_number, description);
89  }
90  
91  bool kunit_suite_has_succeeded(struct kunit_suite *suite)
92  {
93  	const struct kunit_case *test_case;
94  
95  	kunit_suite_for_each_test_case(suite, test_case) {
96  		if (!test_case->success)
97  			return false;
98  	}
99  
100  	return true;
101  }
102  EXPORT_SYMBOL_GPL(kunit_suite_has_succeeded);
103  
104  static void kunit_print_subtest_end(struct kunit_suite *suite)
105  {
106  	static size_t kunit_suite_counter = 1;
107  
108  	kunit_print_ok_not_ok((void *)suite, false,
109  			      kunit_suite_has_succeeded(suite),
110  			      kunit_suite_counter++,
111  			      suite->name);
112  }
113  
114  unsigned int kunit_test_case_num(struct kunit_suite *suite,
115  				 struct kunit_case *test_case)
116  {
117  	struct kunit_case *tc;
118  	unsigned int i = 1;
119  
120  	kunit_suite_for_each_test_case(suite, tc) {
121  		if (tc == test_case)
122  			return i;
123  		i++;
124  	}
125  
126  	return 0;
127  }
128  EXPORT_SYMBOL_GPL(kunit_test_case_num);
129  
130  static void kunit_print_string_stream(struct kunit *test,
131  				      struct string_stream *stream)
132  {
133  	struct string_stream_fragment *fragment;
134  	char *buf;
135  
136  	if (string_stream_is_empty(stream))
137  		return;
138  
139  	buf = string_stream_get_string(stream);
140  	if (!buf) {
141  		kunit_err(test,
142  			  "Could not allocate buffer, dumping stream:\n");
143  		list_for_each_entry(fragment, &stream->fragments, node) {
144  			kunit_err(test, "%s", fragment->fragment);
145  		}
146  		kunit_err(test, "\n");
147  	} else {
148  		kunit_err(test, "%s", buf);
149  		kunit_kfree(test, buf);
150  	}
151  }
152  
153  static void kunit_fail(struct kunit *test, struct kunit_assert *assert)
154  {
155  	struct string_stream *stream;
156  
157  	kunit_set_failure(test);
158  
159  	stream = alloc_string_stream(test, GFP_KERNEL);
160  	if (!stream) {
161  		WARN(true,
162  		     "Could not allocate stream to print failed assertion in %s:%d\n",
163  		     assert->file,
164  		     assert->line);
165  		return;
166  	}
167  
168  	assert->format(assert, stream);
169  
170  	kunit_print_string_stream(test, stream);
171  
172  	WARN_ON(string_stream_destroy(stream));
173  }
174  
175  static void __noreturn kunit_abort(struct kunit *test)
176  {
177  	kunit_try_catch_throw(&test->try_catch); /* Does not return. */
178  
179  	/*
180  	 * Throw could not abort from test.
181  	 *
182  	 * XXX: we should never reach this line! As kunit_try_catch_throw is
183  	 * marked __noreturn.
184  	 */
185  	WARN_ONCE(true, "Throw could not abort from test!\n");
186  }
187  
188  void kunit_do_assertion(struct kunit *test,
189  			struct kunit_assert *assert,
190  			bool pass,
191  			const char *fmt, ...)
192  {
193  	va_list args;
194  
195  	if (pass)
196  		return;
197  
198  	va_start(args, fmt);
199  
200  	assert->message.fmt = fmt;
201  	assert->message.va = &args;
202  
203  	kunit_fail(test, assert);
204  
205  	va_end(args);
206  
207  	if (assert->type == KUNIT_ASSERTION)
208  		kunit_abort(test);
209  }
210  EXPORT_SYMBOL_GPL(kunit_do_assertion);
211  
212  void kunit_init_test(struct kunit *test, const char *name, char *log)
213  {
214  	spin_lock_init(&test->lock);
215  	INIT_LIST_HEAD(&test->resources);
216  	test->name = name;
217  	test->log = log;
218  	if (test->log)
219  		test->log[0] = '\0';
220  	test->success = true;
221  }
222  EXPORT_SYMBOL_GPL(kunit_init_test);
223  
224  /*
225   * Initializes and runs test case. Does not clean up or do post validations.
226   */
227  static void kunit_run_case_internal(struct kunit *test,
228  				    struct kunit_suite *suite,
229  				    struct kunit_case *test_case)
230  {
231  	if (suite->init) {
232  		int ret;
233  
234  		ret = suite->init(test);
235  		if (ret) {
236  			kunit_err(test, "failed to initialize: %d\n", ret);
237  			kunit_set_failure(test);
238  			return;
239  		}
240  	}
241  
242  	test_case->run_case(test);
243  }
244  
245  static void kunit_case_internal_cleanup(struct kunit *test)
246  {
247  	kunit_cleanup(test);
248  }
249  
250  /*
251   * Performs post validations and cleanup after a test case was run.
252   * XXX: Should ONLY BE CALLED AFTER kunit_run_case_internal!
253   */
254  static void kunit_run_case_cleanup(struct kunit *test,
255  				   struct kunit_suite *suite)
256  {
257  	if (suite->exit)
258  		suite->exit(test);
259  
260  	kunit_case_internal_cleanup(test);
261  }
262  
263  struct kunit_try_catch_context {
264  	struct kunit *test;
265  	struct kunit_suite *suite;
266  	struct kunit_case *test_case;
267  };
268  
269  static void kunit_try_run_case(void *data)
270  {
271  	struct kunit_try_catch_context *ctx = data;
272  	struct kunit *test = ctx->test;
273  	struct kunit_suite *suite = ctx->suite;
274  	struct kunit_case *test_case = ctx->test_case;
275  
276  #if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT))
277  	current->kunit_test = test;
278  #endif /* IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT) */
279  
280  	/*
281  	 * kunit_run_case_internal may encounter a fatal error; if it does,
282  	 * abort will be called, this thread will exit, and finally the parent
283  	 * thread will resume control and handle any necessary clean up.
284  	 */
285  	kunit_run_case_internal(test, suite, test_case);
286  	/* This line may never be reached. */
287  	kunit_run_case_cleanup(test, suite);
288  }
289  
290  static void kunit_catch_run_case(void *data)
291  {
292  	struct kunit_try_catch_context *ctx = data;
293  	struct kunit *test = ctx->test;
294  	struct kunit_suite *suite = ctx->suite;
295  	int try_exit_code = kunit_try_catch_get_result(&test->try_catch);
296  
297  	if (try_exit_code) {
298  		kunit_set_failure(test);
299  		/*
300  		 * Test case could not finish, we have no idea what state it is
301  		 * in, so don't do clean up.
302  		 */
303  		if (try_exit_code == -ETIMEDOUT) {
304  			kunit_err(test, "test case timed out\n");
305  		/*
306  		 * Unknown internal error occurred preventing test case from
307  		 * running, so there is nothing to clean up.
308  		 */
309  		} else {
310  			kunit_err(test, "internal error occurred preventing test case from running: %d\n",
311  				  try_exit_code);
312  		}
313  		return;
314  	}
315  
316  	/*
317  	 * Test case was run, but aborted. It is the test case's business as to
318  	 * whether it failed or not, we just need to clean up.
319  	 */
320  	kunit_run_case_cleanup(test, suite);
321  }
322  
323  /*
324   * Performs all logic to run a test case. It also catches most errors that
325   * occur in a test case and reports them as failures.
326   */
327  static void kunit_run_case_catch_errors(struct kunit_suite *suite,
328  					struct kunit_case *test_case,
329  					struct kunit *test)
330  {
331  	struct kunit_try_catch_context context;
332  	struct kunit_try_catch *try_catch;
333  
334  	kunit_init_test(test, test_case->name, test_case->log);
335  	try_catch = &test->try_catch;
336  
337  	kunit_try_catch_init(try_catch,
338  			     test,
339  			     kunit_try_run_case,
340  			     kunit_catch_run_case);
341  	context.test = test;
342  	context.suite = suite;
343  	context.test_case = test_case;
344  	kunit_try_catch_run(try_catch, &context);
345  
346  	test_case->success = test->success;
347  }
348  
349  int kunit_run_tests(struct kunit_suite *suite)
350  {
351  	char param_desc[KUNIT_PARAM_DESC_SIZE];
352  	struct kunit_case *test_case;
353  
354  	kunit_print_subtest_start(suite);
355  
356  	kunit_suite_for_each_test_case(suite, test_case) {
357  		struct kunit test = { .param_value = NULL, .param_index = 0 };
358  		bool test_success = true;
359  
360  		if (test_case->generate_params) {
361  			/* Get initial param. */
362  			param_desc[0] = '\0';
363  			test.param_value = test_case->generate_params(NULL, param_desc);
364  		}
365  
366  		do {
367  			kunit_run_case_catch_errors(suite, test_case, &test);
368  			test_success &= test_case->success;
369  
370  			if (test_case->generate_params) {
371  				if (param_desc[0] == '\0') {
372  					snprintf(param_desc, sizeof(param_desc),
373  						 "param-%d", test.param_index);
374  				}
375  
376  				kunit_log(KERN_INFO, &test,
377  					  KUNIT_SUBTEST_INDENT
378  					  "# %s: %s %d - %s",
379  					  test_case->name,
380  					  kunit_status_to_string(test.success),
381  					  test.param_index + 1, param_desc);
382  
383  				/* Get next param. */
384  				param_desc[0] = '\0';
385  				test.param_value = test_case->generate_params(test.param_value, param_desc);
386  				test.param_index++;
387  			}
388  		} while (test.param_value);
389  
390  		kunit_print_ok_not_ok(&test, true, test_success,
391  				      kunit_test_case_num(suite, test_case),
392  				      test_case->name);
393  	}
394  
395  	kunit_print_subtest_end(suite);
396  
397  	return 0;
398  }
399  EXPORT_SYMBOL_GPL(kunit_run_tests);
400  
401  static void kunit_init_suite(struct kunit_suite *suite)
402  {
403  	kunit_debugfs_create_suite(suite);
404  }
405  
406  int __kunit_test_suites_init(struct kunit_suite * const * const suites)
407  {
408  	unsigned int i;
409  
410  	for (i = 0; suites[i] != NULL; i++) {
411  		kunit_init_suite(suites[i]);
412  		kunit_run_tests(suites[i]);
413  	}
414  	return 0;
415  }
416  EXPORT_SYMBOL_GPL(__kunit_test_suites_init);
417  
418  static void kunit_exit_suite(struct kunit_suite *suite)
419  {
420  	kunit_debugfs_destroy_suite(suite);
421  }
422  
423  void __kunit_test_suites_exit(struct kunit_suite **suites)
424  {
425  	unsigned int i;
426  
427  	for (i = 0; suites[i] != NULL; i++)
428  		kunit_exit_suite(suites[i]);
429  }
430  EXPORT_SYMBOL_GPL(__kunit_test_suites_exit);
431  
432  /*
433   * Used for static resources and when a kunit_resource * has been created by
434   * kunit_alloc_resource().  When an init function is supplied, @data is passed
435   * into the init function; otherwise, we simply set the resource data field to
436   * the data value passed in.
437   */
438  int kunit_add_resource(struct kunit *test,
439  		       kunit_resource_init_t init,
440  		       kunit_resource_free_t free,
441  		       struct kunit_resource *res,
442  		       void *data)
443  {
444  	int ret = 0;
445  
446  	res->free = free;
447  	kref_init(&res->refcount);
448  
449  	if (init) {
450  		ret = init(res, data);
451  		if (ret)
452  			return ret;
453  	} else {
454  		res->data = data;
455  	}
456  
457  	spin_lock(&test->lock);
458  	list_add_tail(&res->node, &test->resources);
459  	/* refcount for list is established by kref_init() */
460  	spin_unlock(&test->lock);
461  
462  	return ret;
463  }
464  EXPORT_SYMBOL_GPL(kunit_add_resource);
465  
466  int kunit_add_named_resource(struct kunit *test,
467  			     kunit_resource_init_t init,
468  			     kunit_resource_free_t free,
469  			     struct kunit_resource *res,
470  			     const char *name,
471  			     void *data)
472  {
473  	struct kunit_resource *existing;
474  
475  	if (!name)
476  		return -EINVAL;
477  
478  	existing = kunit_find_named_resource(test, name);
479  	if (existing) {
480  		kunit_put_resource(existing);
481  		return -EEXIST;
482  	}
483  
484  	res->name = name;
485  
486  	return kunit_add_resource(test, init, free, res, data);
487  }
488  EXPORT_SYMBOL_GPL(kunit_add_named_resource);
489  
490  struct kunit_resource *kunit_alloc_and_get_resource(struct kunit *test,
491  						    kunit_resource_init_t init,
492  						    kunit_resource_free_t free,
493  						    gfp_t internal_gfp,
494  						    void *data)
495  {
496  	struct kunit_resource *res;
497  	int ret;
498  
499  	res = kzalloc(sizeof(*res), internal_gfp);
500  	if (!res)
501  		return NULL;
502  
503  	ret = kunit_add_resource(test, init, free, res, data);
504  	if (!ret) {
505  		/*
506  		 * bump refcount for get; kunit_resource_put() should be called
507  		 * when done.
508  		 */
509  		kunit_get_resource(res);
510  		return res;
511  	}
512  	return NULL;
513  }
514  EXPORT_SYMBOL_GPL(kunit_alloc_and_get_resource);
515  
516  void kunit_remove_resource(struct kunit *test, struct kunit_resource *res)
517  {
518  	spin_lock(&test->lock);
519  	list_del(&res->node);
520  	spin_unlock(&test->lock);
521  	kunit_put_resource(res);
522  }
523  EXPORT_SYMBOL_GPL(kunit_remove_resource);
524  
525  int kunit_destroy_resource(struct kunit *test, kunit_resource_match_t match,
526  			   void *match_data)
527  {
528  	struct kunit_resource *res = kunit_find_resource(test, match,
529  							 match_data);
530  
531  	if (!res)
532  		return -ENOENT;
533  
534  	kunit_remove_resource(test, res);
535  
536  	/* We have a reference also via _find(); drop it. */
537  	kunit_put_resource(res);
538  
539  	return 0;
540  }
541  EXPORT_SYMBOL_GPL(kunit_destroy_resource);
542  
543  struct kunit_kmalloc_params {
544  	size_t size;
545  	gfp_t gfp;
546  };
547  
548  static int kunit_kmalloc_init(struct kunit_resource *res, void *context)
549  {
550  	struct kunit_kmalloc_params *params = context;
551  
552  	res->data = kmalloc(params->size, params->gfp);
553  	if (!res->data)
554  		return -ENOMEM;
555  
556  	return 0;
557  }
558  
559  static void kunit_kmalloc_free(struct kunit_resource *res)
560  {
561  	kfree(res->data);
562  }
563  
564  void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp)
565  {
566  	struct kunit_kmalloc_params params = {
567  		.size = size,
568  		.gfp = gfp
569  	};
570  
571  	return kunit_alloc_resource(test,
572  				    kunit_kmalloc_init,
573  				    kunit_kmalloc_free,
574  				    gfp,
575  				    &params);
576  }
577  EXPORT_SYMBOL_GPL(kunit_kmalloc);
578  
579  void kunit_kfree(struct kunit *test, const void *ptr)
580  {
581  	struct kunit_resource *res;
582  
583  	res = kunit_find_resource(test, kunit_resource_instance_match,
584  				  (void *)ptr);
585  
586  	/*
587  	 * Removing the resource from the list of resources drops the
588  	 * reference count to 1; the final put will trigger the free.
589  	 */
590  	kunit_remove_resource(test, res);
591  
592  	kunit_put_resource(res);
593  
594  }
595  EXPORT_SYMBOL_GPL(kunit_kfree);
596  
597  void kunit_cleanup(struct kunit *test)
598  {
599  	struct kunit_resource *res;
600  
601  	/*
602  	 * test->resources is a stack - each allocation must be freed in the
603  	 * reverse order from which it was added since one resource may depend
604  	 * on another for its entire lifetime.
605  	 * Also, we cannot use the normal list_for_each constructs, even the
606  	 * safe ones because *arbitrary* nodes may be deleted when
607  	 * kunit_resource_free is called; the list_for_each_safe variants only
608  	 * protect against the current node being deleted, not the next.
609  	 */
610  	while (true) {
611  		spin_lock(&test->lock);
612  		if (list_empty(&test->resources)) {
613  			spin_unlock(&test->lock);
614  			break;
615  		}
616  		res = list_last_entry(&test->resources,
617  				      struct kunit_resource,
618  				      node);
619  		/*
620  		 * Need to unlock here as a resource may remove another
621  		 * resource, and this can't happen if the test->lock
622  		 * is held.
623  		 */
624  		spin_unlock(&test->lock);
625  		kunit_remove_resource(test, res);
626  	}
627  #if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT))
628  	current->kunit_test = NULL;
629  #endif /* IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT)*/
630  }
631  EXPORT_SYMBOL_GPL(kunit_cleanup);
632  
633  static int __init kunit_init(void)
634  {
635  	kunit_debugfs_init();
636  
637  	return 0;
638  }
639  late_initcall(kunit_init);
640  
641  static void __exit kunit_exit(void)
642  {
643  	kunit_debugfs_cleanup();
644  }
645  module_exit(kunit_exit);
646  
647  MODULE_LICENSE("GPL v2");
648