1 /*
2 * lib/locking-selftest.c
3 *
4 * Testsuite for various locking APIs: spinlocks, rwlocks,
5 * mutexes and rw-semaphores.
6 *
7 * It is checking both false positives and false negatives.
8 *
9 * Started by Ingo Molnar:
10 *
11 * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
12 */
13 #include <linux/rwsem.h>
14 #include <linux/mutex.h>
15 #include <linux/sched.h>
16 #include <linux/delay.h>
17 #include <linux/lockdep.h>
18 #include <linux/spinlock.h>
19 #include <linux/kallsyms.h>
20 #include <linux/interrupt.h>
21 #include <linux/debug_locks.h>
22 #include <linux/irqflags.h>
23
24 /*
25 * Change this to 1 if you want to see the failure printouts:
26 */
27 static unsigned int debug_locks_verbose;
28
setup_debug_locks_verbose(char * str)29 static int __init setup_debug_locks_verbose(char *str)
30 {
31 get_option(&str, &debug_locks_verbose);
32
33 return 1;
34 }
35
36 __setup("debug_locks_verbose=", setup_debug_locks_verbose);
37
38 #define FAILURE 0
39 #define SUCCESS 1
40
41 #define LOCKTYPE_SPIN 0x1
42 #define LOCKTYPE_RWLOCK 0x2
43 #define LOCKTYPE_MUTEX 0x4
44 #define LOCKTYPE_RWSEM 0x8
45
46 /*
47 * Normal standalone locks, for the circular and irq-context
48 * dependency tests:
49 */
50 static DEFINE_SPINLOCK(lock_A);
51 static DEFINE_SPINLOCK(lock_B);
52 static DEFINE_SPINLOCK(lock_C);
53 static DEFINE_SPINLOCK(lock_D);
54
55 static DEFINE_RWLOCK(rwlock_A);
56 static DEFINE_RWLOCK(rwlock_B);
57 static DEFINE_RWLOCK(rwlock_C);
58 static DEFINE_RWLOCK(rwlock_D);
59
60 static DEFINE_MUTEX(mutex_A);
61 static DEFINE_MUTEX(mutex_B);
62 static DEFINE_MUTEX(mutex_C);
63 static DEFINE_MUTEX(mutex_D);
64
65 static DECLARE_RWSEM(rwsem_A);
66 static DECLARE_RWSEM(rwsem_B);
67 static DECLARE_RWSEM(rwsem_C);
68 static DECLARE_RWSEM(rwsem_D);
69
70 /*
71 * Locks that we initialize dynamically as well so that
72 * e.g. X1 and X2 becomes two instances of the same class,
73 * but X* and Y* are different classes. We do this so that
74 * we do not trigger a real lockup:
75 */
76 static DEFINE_SPINLOCK(lock_X1);
77 static DEFINE_SPINLOCK(lock_X2);
78 static DEFINE_SPINLOCK(lock_Y1);
79 static DEFINE_SPINLOCK(lock_Y2);
80 static DEFINE_SPINLOCK(lock_Z1);
81 static DEFINE_SPINLOCK(lock_Z2);
82
83 static DEFINE_RWLOCK(rwlock_X1);
84 static DEFINE_RWLOCK(rwlock_X2);
85 static DEFINE_RWLOCK(rwlock_Y1);
86 static DEFINE_RWLOCK(rwlock_Y2);
87 static DEFINE_RWLOCK(rwlock_Z1);
88 static DEFINE_RWLOCK(rwlock_Z2);
89
90 static DEFINE_MUTEX(mutex_X1);
91 static DEFINE_MUTEX(mutex_X2);
92 static DEFINE_MUTEX(mutex_Y1);
93 static DEFINE_MUTEX(mutex_Y2);
94 static DEFINE_MUTEX(mutex_Z1);
95 static DEFINE_MUTEX(mutex_Z2);
96
97 static DECLARE_RWSEM(rwsem_X1);
98 static DECLARE_RWSEM(rwsem_X2);
99 static DECLARE_RWSEM(rwsem_Y1);
100 static DECLARE_RWSEM(rwsem_Y2);
101 static DECLARE_RWSEM(rwsem_Z1);
102 static DECLARE_RWSEM(rwsem_Z2);
103
104 /*
105 * non-inlined runtime initializers, to let separate locks share
106 * the same lock-class:
107 */
108 #define INIT_CLASS_FUNC(class) \
109 static noinline void \
110 init_class_##class(spinlock_t *lock, rwlock_t *rwlock, struct mutex *mutex, \
111 struct rw_semaphore *rwsem) \
112 { \
113 spin_lock_init(lock); \
114 rwlock_init(rwlock); \
115 mutex_init(mutex); \
116 init_rwsem(rwsem); \
117 }
118
119 INIT_CLASS_FUNC(X)
INIT_CLASS_FUNC(Y)120 INIT_CLASS_FUNC(Y)
121 INIT_CLASS_FUNC(Z)
122
123 static void init_shared_classes(void)
124 {
125 init_class_X(&lock_X1, &rwlock_X1, &mutex_X1, &rwsem_X1);
126 init_class_X(&lock_X2, &rwlock_X2, &mutex_X2, &rwsem_X2);
127
128 init_class_Y(&lock_Y1, &rwlock_Y1, &mutex_Y1, &rwsem_Y1);
129 init_class_Y(&lock_Y2, &rwlock_Y2, &mutex_Y2, &rwsem_Y2);
130
131 init_class_Z(&lock_Z1, &rwlock_Z1, &mutex_Z1, &rwsem_Z1);
132 init_class_Z(&lock_Z2, &rwlock_Z2, &mutex_Z2, &rwsem_Z2);
133 }
134
135 /*
136 * For spinlocks and rwlocks we also do hardirq-safe / softirq-safe tests.
137 * The following functions use a lock from a simulated hardirq/softirq
138 * context, causing the locks to be marked as hardirq-safe/softirq-safe:
139 */
140
141 #define HARDIRQ_DISABLE local_irq_disable
142 #define HARDIRQ_ENABLE local_irq_enable
143
144 #define HARDIRQ_ENTER() \
145 local_irq_disable(); \
146 __irq_enter(); \
147 WARN_ON(!in_irq());
148
149 #define HARDIRQ_EXIT() \
150 __irq_exit(); \
151 local_irq_enable();
152
153 #define SOFTIRQ_DISABLE local_bh_disable
154 #define SOFTIRQ_ENABLE local_bh_enable
155
156 #define SOFTIRQ_ENTER() \
157 local_bh_disable(); \
158 local_irq_disable(); \
159 lockdep_softirq_enter(); \
160 WARN_ON(!in_softirq());
161
162 #define SOFTIRQ_EXIT() \
163 lockdep_softirq_exit(); \
164 local_irq_enable(); \
165 local_bh_enable();
166
167 /*
168 * Shortcuts for lock/unlock API variants, to keep
169 * the testcases compact:
170 */
171 #define L(x) spin_lock(&lock_##x)
172 #define U(x) spin_unlock(&lock_##x)
173 #define LU(x) L(x); U(x)
174 #define SI(x) spin_lock_init(&lock_##x)
175
176 #define WL(x) write_lock(&rwlock_##x)
177 #define WU(x) write_unlock(&rwlock_##x)
178 #define WLU(x) WL(x); WU(x)
179
180 #define RL(x) read_lock(&rwlock_##x)
181 #define RU(x) read_unlock(&rwlock_##x)
182 #define RLU(x) RL(x); RU(x)
183 #define RWI(x) rwlock_init(&rwlock_##x)
184
185 #define ML(x) mutex_lock(&mutex_##x)
186 #define MU(x) mutex_unlock(&mutex_##x)
187 #define MI(x) mutex_init(&mutex_##x)
188
189 #define WSL(x) down_write(&rwsem_##x)
190 #define WSU(x) up_write(&rwsem_##x)
191
192 #define RSL(x) down_read(&rwsem_##x)
193 #define RSU(x) up_read(&rwsem_##x)
194 #define RWSI(x) init_rwsem(&rwsem_##x)
195
196 #define LOCK_UNLOCK_2(x,y) LOCK(x); LOCK(y); UNLOCK(y); UNLOCK(x)
197
198 /*
199 * Generate different permutations of the same testcase, using
200 * the same basic lock-dependency/state events:
201 */
202
203 #define GENERATE_TESTCASE(name) \
204 \
205 static void name(void) { E(); }
206
207 #define GENERATE_PERMUTATIONS_2_EVENTS(name) \
208 \
209 static void name##_12(void) { E1(); E2(); } \
210 static void name##_21(void) { E2(); E1(); }
211
212 #define GENERATE_PERMUTATIONS_3_EVENTS(name) \
213 \
214 static void name##_123(void) { E1(); E2(); E3(); } \
215 static void name##_132(void) { E1(); E3(); E2(); } \
216 static void name##_213(void) { E2(); E1(); E3(); } \
217 static void name##_231(void) { E2(); E3(); E1(); } \
218 static void name##_312(void) { E3(); E1(); E2(); } \
219 static void name##_321(void) { E3(); E2(); E1(); }
220
221 /*
222 * AA deadlock:
223 */
224
225 #define E() \
226 \
227 LOCK(X1); \
228 LOCK(X2); /* this one should fail */
229
230 /*
231 * 6 testcases:
232 */
233 #include "locking-selftest-spin.h"
234 GENERATE_TESTCASE(AA_spin)
235 #include "locking-selftest-wlock.h"
GENERATE_TESTCASE(AA_wlock)236 GENERATE_TESTCASE(AA_wlock)
237 #include "locking-selftest-rlock.h"
238 GENERATE_TESTCASE(AA_rlock)
239 #include "locking-selftest-mutex.h"
240 GENERATE_TESTCASE(AA_mutex)
241 #include "locking-selftest-wsem.h"
242 GENERATE_TESTCASE(AA_wsem)
243 #include "locking-selftest-rsem.h"
244 GENERATE_TESTCASE(AA_rsem)
245
246 #undef E
247
248 /*
249 * Special-case for read-locking, they are
250 * allowed to recurse on the same lock class:
251 */
252 static void rlock_AA1(void)
253 {
254 RL(X1);
255 RL(X1); // this one should NOT fail
256 }
257
rlock_AA1B(void)258 static void rlock_AA1B(void)
259 {
260 RL(X1);
261 RL(X2); // this one should NOT fail
262 }
263
rsem_AA1(void)264 static void rsem_AA1(void)
265 {
266 RSL(X1);
267 RSL(X1); // this one should fail
268 }
269
rsem_AA1B(void)270 static void rsem_AA1B(void)
271 {
272 RSL(X1);
273 RSL(X2); // this one should fail
274 }
275 /*
276 * The mixing of read and write locks is not allowed:
277 */
rlock_AA2(void)278 static void rlock_AA2(void)
279 {
280 RL(X1);
281 WL(X2); // this one should fail
282 }
283
rsem_AA2(void)284 static void rsem_AA2(void)
285 {
286 RSL(X1);
287 WSL(X2); // this one should fail
288 }
289
rlock_AA3(void)290 static void rlock_AA3(void)
291 {
292 WL(X1);
293 RL(X2); // this one should fail
294 }
295
rsem_AA3(void)296 static void rsem_AA3(void)
297 {
298 WSL(X1);
299 RSL(X2); // this one should fail
300 }
301
302 /*
303 * ABBA deadlock:
304 */
305
306 #define E() \
307 \
308 LOCK_UNLOCK_2(A, B); \
309 LOCK_UNLOCK_2(B, A); /* fail */
310
311 /*
312 * 6 testcases:
313 */
314 #include "locking-selftest-spin.h"
315 GENERATE_TESTCASE(ABBA_spin)
316 #include "locking-selftest-wlock.h"
GENERATE_TESTCASE(ABBA_wlock)317 GENERATE_TESTCASE(ABBA_wlock)
318 #include "locking-selftest-rlock.h"
319 GENERATE_TESTCASE(ABBA_rlock)
320 #include "locking-selftest-mutex.h"
321 GENERATE_TESTCASE(ABBA_mutex)
322 #include "locking-selftest-wsem.h"
323 GENERATE_TESTCASE(ABBA_wsem)
324 #include "locking-selftest-rsem.h"
325 GENERATE_TESTCASE(ABBA_rsem)
326
327 #undef E
328
329 /*
330 * AB BC CA deadlock:
331 */
332
333 #define E() \
334 \
335 LOCK_UNLOCK_2(A, B); \
336 LOCK_UNLOCK_2(B, C); \
337 LOCK_UNLOCK_2(C, A); /* fail */
338
339 /*
340 * 6 testcases:
341 */
342 #include "locking-selftest-spin.h"
343 GENERATE_TESTCASE(ABBCCA_spin)
344 #include "locking-selftest-wlock.h"
345 GENERATE_TESTCASE(ABBCCA_wlock)
346 #include "locking-selftest-rlock.h"
347 GENERATE_TESTCASE(ABBCCA_rlock)
348 #include "locking-selftest-mutex.h"
349 GENERATE_TESTCASE(ABBCCA_mutex)
350 #include "locking-selftest-wsem.h"
351 GENERATE_TESTCASE(ABBCCA_wsem)
352 #include "locking-selftest-rsem.h"
353 GENERATE_TESTCASE(ABBCCA_rsem)
354
355 #undef E
356
357 /*
358 * AB CA BC deadlock:
359 */
360
361 #define E() \
362 \
363 LOCK_UNLOCK_2(A, B); \
364 LOCK_UNLOCK_2(C, A); \
365 LOCK_UNLOCK_2(B, C); /* fail */
366
367 /*
368 * 6 testcases:
369 */
370 #include "locking-selftest-spin.h"
371 GENERATE_TESTCASE(ABCABC_spin)
372 #include "locking-selftest-wlock.h"
373 GENERATE_TESTCASE(ABCABC_wlock)
374 #include "locking-selftest-rlock.h"
375 GENERATE_TESTCASE(ABCABC_rlock)
376 #include "locking-selftest-mutex.h"
377 GENERATE_TESTCASE(ABCABC_mutex)
378 #include "locking-selftest-wsem.h"
379 GENERATE_TESTCASE(ABCABC_wsem)
380 #include "locking-selftest-rsem.h"
381 GENERATE_TESTCASE(ABCABC_rsem)
382
383 #undef E
384
385 /*
386 * AB BC CD DA deadlock:
387 */
388
389 #define E() \
390 \
391 LOCK_UNLOCK_2(A, B); \
392 LOCK_UNLOCK_2(B, C); \
393 LOCK_UNLOCK_2(C, D); \
394 LOCK_UNLOCK_2(D, A); /* fail */
395
396 /*
397 * 6 testcases:
398 */
399 #include "locking-selftest-spin.h"
400 GENERATE_TESTCASE(ABBCCDDA_spin)
401 #include "locking-selftest-wlock.h"
402 GENERATE_TESTCASE(ABBCCDDA_wlock)
403 #include "locking-selftest-rlock.h"
404 GENERATE_TESTCASE(ABBCCDDA_rlock)
405 #include "locking-selftest-mutex.h"
406 GENERATE_TESTCASE(ABBCCDDA_mutex)
407 #include "locking-selftest-wsem.h"
408 GENERATE_TESTCASE(ABBCCDDA_wsem)
409 #include "locking-selftest-rsem.h"
410 GENERATE_TESTCASE(ABBCCDDA_rsem)
411
412 #undef E
413
414 /*
415 * AB CD BD DA deadlock:
416 */
417 #define E() \
418 \
419 LOCK_UNLOCK_2(A, B); \
420 LOCK_UNLOCK_2(C, D); \
421 LOCK_UNLOCK_2(B, D); \
422 LOCK_UNLOCK_2(D, A); /* fail */
423
424 /*
425 * 6 testcases:
426 */
427 #include "locking-selftest-spin.h"
428 GENERATE_TESTCASE(ABCDBDDA_spin)
429 #include "locking-selftest-wlock.h"
430 GENERATE_TESTCASE(ABCDBDDA_wlock)
431 #include "locking-selftest-rlock.h"
432 GENERATE_TESTCASE(ABCDBDDA_rlock)
433 #include "locking-selftest-mutex.h"
434 GENERATE_TESTCASE(ABCDBDDA_mutex)
435 #include "locking-selftest-wsem.h"
436 GENERATE_TESTCASE(ABCDBDDA_wsem)
437 #include "locking-selftest-rsem.h"
438 GENERATE_TESTCASE(ABCDBDDA_rsem)
439
440 #undef E
441
442 /*
443 * AB CD BC DA deadlock:
444 */
445 #define E() \
446 \
447 LOCK_UNLOCK_2(A, B); \
448 LOCK_UNLOCK_2(C, D); \
449 LOCK_UNLOCK_2(B, C); \
450 LOCK_UNLOCK_2(D, A); /* fail */
451
452 /*
453 * 6 testcases:
454 */
455 #include "locking-selftest-spin.h"
456 GENERATE_TESTCASE(ABCDBCDA_spin)
457 #include "locking-selftest-wlock.h"
458 GENERATE_TESTCASE(ABCDBCDA_wlock)
459 #include "locking-selftest-rlock.h"
460 GENERATE_TESTCASE(ABCDBCDA_rlock)
461 #include "locking-selftest-mutex.h"
462 GENERATE_TESTCASE(ABCDBCDA_mutex)
463 #include "locking-selftest-wsem.h"
464 GENERATE_TESTCASE(ABCDBCDA_wsem)
465 #include "locking-selftest-rsem.h"
466 GENERATE_TESTCASE(ABCDBCDA_rsem)
467
468 #undef E
469
470 /*
471 * Double unlock:
472 */
473 #define E() \
474 \
475 LOCK(A); \
476 UNLOCK(A); \
477 UNLOCK(A); /* fail */
478
479 /*
480 * 6 testcases:
481 */
482 #include "locking-selftest-spin.h"
483 GENERATE_TESTCASE(double_unlock_spin)
484 #include "locking-selftest-wlock.h"
485 GENERATE_TESTCASE(double_unlock_wlock)
486 #include "locking-selftest-rlock.h"
487 GENERATE_TESTCASE(double_unlock_rlock)
488 #include "locking-selftest-mutex.h"
489 GENERATE_TESTCASE(double_unlock_mutex)
490 #include "locking-selftest-wsem.h"
491 GENERATE_TESTCASE(double_unlock_wsem)
492 #include "locking-selftest-rsem.h"
493 GENERATE_TESTCASE(double_unlock_rsem)
494
495 #undef E
496
497 /*
498 * Bad unlock ordering:
499 */
500 #define E() \
501 \
502 LOCK(A); \
503 LOCK(B); \
504 UNLOCK(A); /* fail */ \
505 UNLOCK(B);
506
507 /*
508 * 6 testcases:
509 */
510 #include "locking-selftest-spin.h"
511 GENERATE_TESTCASE(bad_unlock_order_spin)
512 #include "locking-selftest-wlock.h"
513 GENERATE_TESTCASE(bad_unlock_order_wlock)
514 #include "locking-selftest-rlock.h"
515 GENERATE_TESTCASE(bad_unlock_order_rlock)
516 #include "locking-selftest-mutex.h"
517 GENERATE_TESTCASE(bad_unlock_order_mutex)
518 #include "locking-selftest-wsem.h"
519 GENERATE_TESTCASE(bad_unlock_order_wsem)
520 #include "locking-selftest-rsem.h"
521 GENERATE_TESTCASE(bad_unlock_order_rsem)
522
523 #undef E
524
525 /*
526 * initializing a held lock:
527 */
528 #define E() \
529 \
530 LOCK(A); \
531 INIT(A); /* fail */
532
533 /*
534 * 6 testcases:
535 */
536 #include "locking-selftest-spin.h"
537 GENERATE_TESTCASE(init_held_spin)
538 #include "locking-selftest-wlock.h"
539 GENERATE_TESTCASE(init_held_wlock)
540 #include "locking-selftest-rlock.h"
541 GENERATE_TESTCASE(init_held_rlock)
542 #include "locking-selftest-mutex.h"
543 GENERATE_TESTCASE(init_held_mutex)
544 #include "locking-selftest-wsem.h"
545 GENERATE_TESTCASE(init_held_wsem)
546 #include "locking-selftest-rsem.h"
547 GENERATE_TESTCASE(init_held_rsem)
548
549 #undef E
550
551 /*
552 * locking an irq-safe lock with irqs enabled:
553 */
554 #define E1() \
555 \
556 IRQ_ENTER(); \
557 LOCK(A); \
558 UNLOCK(A); \
559 IRQ_EXIT();
560
561 #define E2() \
562 \
563 LOCK(A); \
564 UNLOCK(A);
565
566 /*
567 * Generate 24 testcases:
568 */
569 #include "locking-selftest-spin-hardirq.h"
570 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
571
572 #include "locking-selftest-rlock-hardirq.h"
573 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
574
575 #include "locking-selftest-wlock-hardirq.h"
576 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_wlock)
577
578 #include "locking-selftest-spin-softirq.h"
579 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_spin)
580
581 #include "locking-selftest-rlock-softirq.h"
582 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock)
583
584 #include "locking-selftest-wlock-softirq.h"
585 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock)
586
587 #undef E1
588 #undef E2
589
590 /*
591 * Enabling hardirqs with a softirq-safe lock held:
592 */
593 #define E1() \
594 \
595 SOFTIRQ_ENTER(); \
596 LOCK(A); \
597 UNLOCK(A); \
598 SOFTIRQ_EXIT();
599
600 #define E2() \
601 \
602 HARDIRQ_DISABLE(); \
603 LOCK(A); \
604 HARDIRQ_ENABLE(); \
605 UNLOCK(A);
606
607 /*
608 * Generate 12 testcases:
609 */
610 #include "locking-selftest-spin.h"
611 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_spin)
612
613 #include "locking-selftest-wlock.h"
614 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_wlock)
615
616 #include "locking-selftest-rlock.h"
617 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
618
619 #undef E1
620 #undef E2
621
622 /*
623 * Enabling irqs with an irq-safe lock held:
624 */
625 #define E1() \
626 \
627 IRQ_ENTER(); \
628 LOCK(A); \
629 UNLOCK(A); \
630 IRQ_EXIT();
631
632 #define E2() \
633 \
634 IRQ_DISABLE(); \
635 LOCK(A); \
636 IRQ_ENABLE(); \
637 UNLOCK(A);
638
639 /*
640 * Generate 24 testcases:
641 */
642 #include "locking-selftest-spin-hardirq.h"
643 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
644
645 #include "locking-selftest-rlock-hardirq.h"
646 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
647
648 #include "locking-selftest-wlock-hardirq.h"
649 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_wlock)
650
651 #include "locking-selftest-spin-softirq.h"
652 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_spin)
653
654 #include "locking-selftest-rlock-softirq.h"
655 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock)
656
657 #include "locking-selftest-wlock-softirq.h"
658 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
659
660 #undef E1
661 #undef E2
662
663 /*
664 * Acquiring a irq-unsafe lock while holding an irq-safe-lock:
665 */
666 #define E1() \
667 \
668 LOCK(A); \
669 LOCK(B); \
670 UNLOCK(B); \
671 UNLOCK(A); \
672
673 #define E2() \
674 \
675 LOCK(B); \
676 UNLOCK(B);
677
678 #define E3() \
679 \
680 IRQ_ENTER(); \
681 LOCK(A); \
682 UNLOCK(A); \
683 IRQ_EXIT();
684
685 /*
686 * Generate 36 testcases:
687 */
688 #include "locking-selftest-spin-hardirq.h"
689 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
690
691 #include "locking-selftest-rlock-hardirq.h"
692 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
693
694 #include "locking-selftest-wlock-hardirq.h"
695 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_wlock)
696
697 #include "locking-selftest-spin-softirq.h"
698 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_spin)
699
700 #include "locking-selftest-rlock-softirq.h"
701 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock)
702
703 #include "locking-selftest-wlock-softirq.h"
704 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
705
706 #undef E1
707 #undef E2
708 #undef E3
709
710 /*
711 * If a lock turns into softirq-safe, but earlier it took
712 * a softirq-unsafe lock:
713 */
714
715 #define E1() \
716 IRQ_DISABLE(); \
717 LOCK(A); \
718 LOCK(B); \
719 UNLOCK(B); \
720 UNLOCK(A); \
721 IRQ_ENABLE();
722
723 #define E2() \
724 LOCK(B); \
725 UNLOCK(B);
726
727 #define E3() \
728 IRQ_ENTER(); \
729 LOCK(A); \
730 UNLOCK(A); \
731 IRQ_EXIT();
732
733 /*
734 * Generate 36 testcases:
735 */
736 #include "locking-selftest-spin-hardirq.h"
737 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
738
739 #include "locking-selftest-rlock-hardirq.h"
740 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
741
742 #include "locking-selftest-wlock-hardirq.h"
743 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_wlock)
744
745 #include "locking-selftest-spin-softirq.h"
746 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_spin)
747
748 #include "locking-selftest-rlock-softirq.h"
749 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock)
750
751 #include "locking-selftest-wlock-softirq.h"
752 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)
753
754 #undef E1
755 #undef E2
756 #undef E3
757
758 /*
759 * read-lock / write-lock irq inversion.
760 *
761 * Deadlock scenario:
762 *
763 * CPU#1 is at #1, i.e. it has write-locked A, but has not
764 * taken B yet.
765 *
766 * CPU#2 is at #2, i.e. it has locked B.
767 *
768 * Hardirq hits CPU#2 at point #2 and is trying to read-lock A.
769 *
770 * The deadlock occurs because CPU#1 will spin on B, and CPU#2
771 * will spin on A.
772 */
773
774 #define E1() \
775 \
776 IRQ_DISABLE(); \
777 WL(A); \
778 LOCK(B); \
779 UNLOCK(B); \
780 WU(A); \
781 IRQ_ENABLE();
782
783 #define E2() \
784 \
785 LOCK(B); \
786 UNLOCK(B);
787
788 #define E3() \
789 \
790 IRQ_ENTER(); \
791 RL(A); \
792 RU(A); \
793 IRQ_EXIT();
794
795 /*
796 * Generate 36 testcases:
797 */
798 #include "locking-selftest-spin-hardirq.h"
799 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_spin)
800
801 #include "locking-selftest-rlock-hardirq.h"
802 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_rlock)
803
804 #include "locking-selftest-wlock-hardirq.h"
805 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_wlock)
806
807 #include "locking-selftest-spin-softirq.h"
808 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_spin)
809
810 #include "locking-selftest-rlock-softirq.h"
811 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_rlock)
812
813 #include "locking-selftest-wlock-softirq.h"
814 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_wlock)
815
816 #undef E1
817 #undef E2
818 #undef E3
819
820 /*
821 * read-lock / write-lock recursion that is actually safe.
822 */
823
824 #define E1() \
825 \
826 IRQ_DISABLE(); \
827 WL(A); \
828 WU(A); \
829 IRQ_ENABLE();
830
831 #define E2() \
832 \
833 RL(A); \
834 RU(A); \
835
836 #define E3() \
837 \
838 IRQ_ENTER(); \
839 RL(A); \
840 L(B); \
841 U(B); \
842 RU(A); \
843 IRQ_EXIT();
844
845 /*
846 * Generate 12 testcases:
847 */
848 #include "locking-selftest-hardirq.h"
849 GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_hard)
850
851 #include "locking-selftest-softirq.h"
852 GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
853
854 #undef E1
855 #undef E2
856 #undef E3
857
858 /*
859 * read-lock / write-lock recursion that is unsafe.
860 */
861
862 #define E1() \
863 \
864 IRQ_DISABLE(); \
865 L(B); \
866 WL(A); \
867 WU(A); \
868 U(B); \
869 IRQ_ENABLE();
870
871 #define E2() \
872 \
873 RL(A); \
874 RU(A); \
875
876 #define E3() \
877 \
878 IRQ_ENTER(); \
879 L(B); \
880 U(B); \
881 IRQ_EXIT();
882
883 /*
884 * Generate 12 testcases:
885 */
886 #include "locking-selftest-hardirq.h"
887 // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_hard)
888
889 #include "locking-selftest-softirq.h"
890 // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_soft)
891
892 #ifdef CONFIG_DEBUG_LOCK_ALLOC
893 # define I_SPINLOCK(x) lockdep_reset_lock(&lock_##x.dep_map)
894 # define I_RWLOCK(x) lockdep_reset_lock(&rwlock_##x.dep_map)
895 # define I_MUTEX(x) lockdep_reset_lock(&mutex_##x.dep_map)
896 # define I_RWSEM(x) lockdep_reset_lock(&rwsem_##x.dep_map)
897 #else
898 # define I_SPINLOCK(x)
899 # define I_RWLOCK(x)
900 # define I_MUTEX(x)
901 # define I_RWSEM(x)
902 #endif
903
904 #define I1(x) \
905 do { \
906 I_SPINLOCK(x); \
907 I_RWLOCK(x); \
908 I_MUTEX(x); \
909 I_RWSEM(x); \
910 } while (0)
911
912 #define I2(x) \
913 do { \
914 spin_lock_init(&lock_##x); \
915 rwlock_init(&rwlock_##x); \
916 mutex_init(&mutex_##x); \
917 init_rwsem(&rwsem_##x); \
918 } while (0)
919
920 static void reset_locks(void)
921 {
922 local_irq_disable();
923 I1(A); I1(B); I1(C); I1(D);
924 I1(X1); I1(X2); I1(Y1); I1(Y2); I1(Z1); I1(Z2);
925 lockdep_reset();
926 I2(A); I2(B); I2(C); I2(D);
927 init_shared_classes();
928 local_irq_enable();
929 }
930
931 #undef I
932
933 static int testcase_total;
934 static int testcase_successes;
935 static int expected_testcase_failures;
936 static int unexpected_testcase_failures;
937
dotest(void (* testcase_fn)(void),int expected,int lockclass_mask)938 static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
939 {
940 unsigned long saved_preempt_count = preempt_count();
941 int expected_failure = 0;
942
943 WARN_ON(irqs_disabled());
944
945 testcase_fn();
946 /*
947 * Filter out expected failures:
948 */
949 #ifndef CONFIG_PROVE_LOCKING
950 if ((lockclass_mask & LOCKTYPE_SPIN) && debug_locks != expected)
951 expected_failure = 1;
952 if ((lockclass_mask & LOCKTYPE_RWLOCK) && debug_locks != expected)
953 expected_failure = 1;
954 if ((lockclass_mask & LOCKTYPE_MUTEX) && debug_locks != expected)
955 expected_failure = 1;
956 if ((lockclass_mask & LOCKTYPE_RWSEM) && debug_locks != expected)
957 expected_failure = 1;
958 #endif
959 if (debug_locks != expected) {
960 if (expected_failure) {
961 expected_testcase_failures++;
962 printk("failed|");
963 } else {
964 unexpected_testcase_failures++;
965
966 printk("FAILED|");
967 dump_stack();
968 }
969 } else {
970 testcase_successes++;
971 printk(" ok |");
972 }
973 testcase_total++;
974
975 if (debug_locks_verbose)
976 printk(" lockclass mask: %x, debug_locks: %d, expected: %d\n",
977 lockclass_mask, debug_locks, expected);
978 /*
979 * Some tests (e.g. double-unlock) might corrupt the preemption
980 * count, so restore it:
981 */
982 preempt_count() = saved_preempt_count;
983 #ifdef CONFIG_TRACE_IRQFLAGS
984 if (softirq_count())
985 current->softirqs_enabled = 0;
986 else
987 current->softirqs_enabled = 1;
988 #endif
989
990 reset_locks();
991 }
992
print_testname(const char * testname)993 static inline void print_testname(const char *testname)
994 {
995 printk("%33s:", testname);
996 }
997
998 #define DO_TESTCASE_1(desc, name, nr) \
999 print_testname(desc"/"#nr); \
1000 dotest(name##_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1001 printk("\n");
1002
1003 #define DO_TESTCASE_1B(desc, name, nr) \
1004 print_testname(desc"/"#nr); \
1005 dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1006 printk("\n");
1007
1008 #define DO_TESTCASE_3(desc, name, nr) \
1009 print_testname(desc"/"#nr); \
1010 dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN); \
1011 dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1012 dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1013 printk("\n");
1014
1015 #define DO_TESTCASE_3RW(desc, name, nr) \
1016 print_testname(desc"/"#nr); \
1017 dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN|LOCKTYPE_RWLOCK);\
1018 dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1019 dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1020 printk("\n");
1021
1022 #define DO_TESTCASE_6(desc, name) \
1023 print_testname(desc); \
1024 dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \
1025 dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \
1026 dotest(name##_rlock, FAILURE, LOCKTYPE_RWLOCK); \
1027 dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \
1028 dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \
1029 dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \
1030 printk("\n");
1031
1032 #define DO_TESTCASE_6_SUCCESS(desc, name) \
1033 print_testname(desc); \
1034 dotest(name##_spin, SUCCESS, LOCKTYPE_SPIN); \
1035 dotest(name##_wlock, SUCCESS, LOCKTYPE_RWLOCK); \
1036 dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \
1037 dotest(name##_mutex, SUCCESS, LOCKTYPE_MUTEX); \
1038 dotest(name##_wsem, SUCCESS, LOCKTYPE_RWSEM); \
1039 dotest(name##_rsem, SUCCESS, LOCKTYPE_RWSEM); \
1040 printk("\n");
1041
1042 /*
1043 * 'read' variant: rlocks must not trigger.
1044 */
1045 #define DO_TESTCASE_6R(desc, name) \
1046 print_testname(desc); \
1047 dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \
1048 dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \
1049 dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \
1050 dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \
1051 dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \
1052 dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \
1053 printk("\n");
1054
1055 #define DO_TESTCASE_2I(desc, name, nr) \
1056 DO_TESTCASE_1("hard-"desc, name##_hard, nr); \
1057 DO_TESTCASE_1("soft-"desc, name##_soft, nr);
1058
1059 #define DO_TESTCASE_2IB(desc, name, nr) \
1060 DO_TESTCASE_1B("hard-"desc, name##_hard, nr); \
1061 DO_TESTCASE_1B("soft-"desc, name##_soft, nr);
1062
1063 #define DO_TESTCASE_6I(desc, name, nr) \
1064 DO_TESTCASE_3("hard-"desc, name##_hard, nr); \
1065 DO_TESTCASE_3("soft-"desc, name##_soft, nr);
1066
1067 #define DO_TESTCASE_6IRW(desc, name, nr) \
1068 DO_TESTCASE_3RW("hard-"desc, name##_hard, nr); \
1069 DO_TESTCASE_3RW("soft-"desc, name##_soft, nr);
1070
1071 #define DO_TESTCASE_2x3(desc, name) \
1072 DO_TESTCASE_3(desc, name, 12); \
1073 DO_TESTCASE_3(desc, name, 21);
1074
1075 #define DO_TESTCASE_2x6(desc, name) \
1076 DO_TESTCASE_6I(desc, name, 12); \
1077 DO_TESTCASE_6I(desc, name, 21);
1078
1079 #define DO_TESTCASE_6x2(desc, name) \
1080 DO_TESTCASE_2I(desc, name, 123); \
1081 DO_TESTCASE_2I(desc, name, 132); \
1082 DO_TESTCASE_2I(desc, name, 213); \
1083 DO_TESTCASE_2I(desc, name, 231); \
1084 DO_TESTCASE_2I(desc, name, 312); \
1085 DO_TESTCASE_2I(desc, name, 321);
1086
1087 #define DO_TESTCASE_6x2B(desc, name) \
1088 DO_TESTCASE_2IB(desc, name, 123); \
1089 DO_TESTCASE_2IB(desc, name, 132); \
1090 DO_TESTCASE_2IB(desc, name, 213); \
1091 DO_TESTCASE_2IB(desc, name, 231); \
1092 DO_TESTCASE_2IB(desc, name, 312); \
1093 DO_TESTCASE_2IB(desc, name, 321);
1094
1095 #define DO_TESTCASE_6x6(desc, name) \
1096 DO_TESTCASE_6I(desc, name, 123); \
1097 DO_TESTCASE_6I(desc, name, 132); \
1098 DO_TESTCASE_6I(desc, name, 213); \
1099 DO_TESTCASE_6I(desc, name, 231); \
1100 DO_TESTCASE_6I(desc, name, 312); \
1101 DO_TESTCASE_6I(desc, name, 321);
1102
1103 #define DO_TESTCASE_6x6RW(desc, name) \
1104 DO_TESTCASE_6IRW(desc, name, 123); \
1105 DO_TESTCASE_6IRW(desc, name, 132); \
1106 DO_TESTCASE_6IRW(desc, name, 213); \
1107 DO_TESTCASE_6IRW(desc, name, 231); \
1108 DO_TESTCASE_6IRW(desc, name, 312); \
1109 DO_TESTCASE_6IRW(desc, name, 321);
1110
1111
locking_selftest(void)1112 void locking_selftest(void)
1113 {
1114 /*
1115 * Got a locking failure before the selftest ran?
1116 */
1117 if (!debug_locks) {
1118 printk("----------------------------------\n");
1119 printk("| Locking API testsuite disabled |\n");
1120 printk("----------------------------------\n");
1121 return;
1122 }
1123
1124 /*
1125 * Run the testsuite:
1126 */
1127 printk("------------------------\n");
1128 printk("| Locking API testsuite:\n");
1129 printk("----------------------------------------------------------------------------\n");
1130 printk(" | spin |wlock |rlock |mutex | wsem | rsem |\n");
1131 printk(" --------------------------------------------------------------------------\n");
1132
1133 init_shared_classes();
1134 debug_locks_silent = !debug_locks_verbose;
1135
1136 DO_TESTCASE_6R("A-A deadlock", AA);
1137 DO_TESTCASE_6R("A-B-B-A deadlock", ABBA);
1138 DO_TESTCASE_6R("A-B-B-C-C-A deadlock", ABBCCA);
1139 DO_TESTCASE_6R("A-B-C-A-B-C deadlock", ABCABC);
1140 DO_TESTCASE_6R("A-B-B-C-C-D-D-A deadlock", ABBCCDDA);
1141 DO_TESTCASE_6R("A-B-C-D-B-D-D-A deadlock", ABCDBDDA);
1142 DO_TESTCASE_6R("A-B-C-D-B-C-D-A deadlock", ABCDBCDA);
1143 DO_TESTCASE_6("double unlock", double_unlock);
1144 DO_TESTCASE_6("initialize held", init_held);
1145 DO_TESTCASE_6_SUCCESS("bad unlock order", bad_unlock_order);
1146
1147 printk(" --------------------------------------------------------------------------\n");
1148 print_testname("recursive read-lock");
1149 printk(" |");
1150 dotest(rlock_AA1, SUCCESS, LOCKTYPE_RWLOCK);
1151 printk(" |");
1152 dotest(rsem_AA1, FAILURE, LOCKTYPE_RWSEM);
1153 printk("\n");
1154
1155 print_testname("recursive read-lock #2");
1156 printk(" |");
1157 dotest(rlock_AA1B, SUCCESS, LOCKTYPE_RWLOCK);
1158 printk(" |");
1159 dotest(rsem_AA1B, FAILURE, LOCKTYPE_RWSEM);
1160 printk("\n");
1161
1162 print_testname("mixed read-write-lock");
1163 printk(" |");
1164 dotest(rlock_AA2, FAILURE, LOCKTYPE_RWLOCK);
1165 printk(" |");
1166 dotest(rsem_AA2, FAILURE, LOCKTYPE_RWSEM);
1167 printk("\n");
1168
1169 print_testname("mixed write-read-lock");
1170 printk(" |");
1171 dotest(rlock_AA3, FAILURE, LOCKTYPE_RWLOCK);
1172 printk(" |");
1173 dotest(rsem_AA3, FAILURE, LOCKTYPE_RWSEM);
1174 printk("\n");
1175
1176 printk(" --------------------------------------------------------------------------\n");
1177
1178 /*
1179 * irq-context testcases:
1180 */
1181 DO_TESTCASE_2x6("irqs-on + irq-safe-A", irqsafe1);
1182 DO_TESTCASE_2x3("sirq-safe-A => hirqs-on", irqsafe2A);
1183 DO_TESTCASE_2x6("safe-A + irqs-on", irqsafe2B);
1184 DO_TESTCASE_6x6("safe-A + unsafe-B #1", irqsafe3);
1185 DO_TESTCASE_6x6("safe-A + unsafe-B #2", irqsafe4);
1186 DO_TESTCASE_6x6RW("irq lock-inversion", irq_inversion);
1187
1188 DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
1189 // DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);
1190
1191 if (unexpected_testcase_failures) {
1192 printk("-----------------------------------------------------------------\n");
1193 debug_locks = 0;
1194 printk("BUG: %3d unexpected failures (out of %3d) - debugging disabled! |\n",
1195 unexpected_testcase_failures, testcase_total);
1196 printk("-----------------------------------------------------------------\n");
1197 } else if (expected_testcase_failures && testcase_successes) {
1198 printk("--------------------------------------------------------\n");
1199 printk("%3d out of %3d testcases failed, as expected. |\n",
1200 expected_testcase_failures, testcase_total);
1201 printk("----------------------------------------------------\n");
1202 debug_locks = 1;
1203 } else if (expected_testcase_failures && !testcase_successes) {
1204 printk("--------------------------------------------------------\n");
1205 printk("All %3d testcases failed, as expected. |\n",
1206 expected_testcase_failures);
1207 printk("----------------------------------------\n");
1208 debug_locks = 1;
1209 } else {
1210 printk("-------------------------------------------------------\n");
1211 printk("Good, all %3d testcases passed! |\n",
1212 testcase_successes);
1213 printk("---------------------------------\n");
1214 debug_locks = 1;
1215 }
1216 debug_locks_silent = 0;
1217 }
1218