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/module.h>
18 #include <linux/lockdep.h>
19 #include <linux/spinlock.h>
20 #include <linux/kallsyms.h>
21 #include <linux/interrupt.h>
22 #include <linux/debug_locks.h>
23 #include <linux/irqflags.h>
24
25 /*
26 * Change this to 1 if you want to see the failure printouts:
27 */
28 static unsigned int debug_locks_verbose;
29
setup_debug_locks_verbose(char * str)30 static int __init setup_debug_locks_verbose(char *str)
31 {
32 get_option(&str, &debug_locks_verbose);
33
34 return 1;
35 }
36
37 __setup("debug_locks_verbose=", setup_debug_locks_verbose);
38
39 #define FAILURE 0
40 #define SUCCESS 1
41
42 #define LOCKTYPE_SPIN 0x1
43 #define LOCKTYPE_RWLOCK 0x2
44 #define LOCKTYPE_MUTEX 0x4
45 #define LOCKTYPE_RWSEM 0x8
46
47 /*
48 * Normal standalone locks, for the circular and irq-context
49 * dependency tests:
50 */
51 static DEFINE_SPINLOCK(lock_A);
52 static DEFINE_SPINLOCK(lock_B);
53 static DEFINE_SPINLOCK(lock_C);
54 static DEFINE_SPINLOCK(lock_D);
55
56 static DEFINE_RWLOCK(rwlock_A);
57 static DEFINE_RWLOCK(rwlock_B);
58 static DEFINE_RWLOCK(rwlock_C);
59 static DEFINE_RWLOCK(rwlock_D);
60
61 static DEFINE_MUTEX(mutex_A);
62 static DEFINE_MUTEX(mutex_B);
63 static DEFINE_MUTEX(mutex_C);
64 static DEFINE_MUTEX(mutex_D);
65
66 static DECLARE_RWSEM(rwsem_A);
67 static DECLARE_RWSEM(rwsem_B);
68 static DECLARE_RWSEM(rwsem_C);
69 static DECLARE_RWSEM(rwsem_D);
70
71 /*
72 * Locks that we initialize dynamically as well so that
73 * e.g. X1 and X2 becomes two instances of the same class,
74 * but X* and Y* are different classes. We do this so that
75 * we do not trigger a real lockup:
76 */
77 static DEFINE_SPINLOCK(lock_X1);
78 static DEFINE_SPINLOCK(lock_X2);
79 static DEFINE_SPINLOCK(lock_Y1);
80 static DEFINE_SPINLOCK(lock_Y2);
81 static DEFINE_SPINLOCK(lock_Z1);
82 static DEFINE_SPINLOCK(lock_Z2);
83
84 static DEFINE_RWLOCK(rwlock_X1);
85 static DEFINE_RWLOCK(rwlock_X2);
86 static DEFINE_RWLOCK(rwlock_Y1);
87 static DEFINE_RWLOCK(rwlock_Y2);
88 static DEFINE_RWLOCK(rwlock_Z1);
89 static DEFINE_RWLOCK(rwlock_Z2);
90
91 static DEFINE_MUTEX(mutex_X1);
92 static DEFINE_MUTEX(mutex_X2);
93 static DEFINE_MUTEX(mutex_Y1);
94 static DEFINE_MUTEX(mutex_Y2);
95 static DEFINE_MUTEX(mutex_Z1);
96 static DEFINE_MUTEX(mutex_Z2);
97
98 static DECLARE_RWSEM(rwsem_X1);
99 static DECLARE_RWSEM(rwsem_X2);
100 static DECLARE_RWSEM(rwsem_Y1);
101 static DECLARE_RWSEM(rwsem_Y2);
102 static DECLARE_RWSEM(rwsem_Z1);
103 static DECLARE_RWSEM(rwsem_Z2);
104
105 /*
106 * non-inlined runtime initializers, to let separate locks share
107 * the same lock-class:
108 */
109 #define INIT_CLASS_FUNC(class) \
110 static noinline void \
111 init_class_##class(spinlock_t *lock, rwlock_t *rwlock, struct mutex *mutex, \
112 struct rw_semaphore *rwsem) \
113 { \
114 spin_lock_init(lock); \
115 rwlock_init(rwlock); \
116 mutex_init(mutex); \
117 init_rwsem(rwsem); \
118 }
119
120 INIT_CLASS_FUNC(X)
INIT_CLASS_FUNC(Y)121 INIT_CLASS_FUNC(Y)
122 INIT_CLASS_FUNC(Z)
123
124 static void init_shared_classes(void)
125 {
126 init_class_X(&lock_X1, &rwlock_X1, &mutex_X1, &rwsem_X1);
127 init_class_X(&lock_X2, &rwlock_X2, &mutex_X2, &rwsem_X2);
128
129 init_class_Y(&lock_Y1, &rwlock_Y1, &mutex_Y1, &rwsem_Y1);
130 init_class_Y(&lock_Y2, &rwlock_Y2, &mutex_Y2, &rwsem_Y2);
131
132 init_class_Z(&lock_Z1, &rwlock_Z1, &mutex_Z1, &rwsem_Z1);
133 init_class_Z(&lock_Z2, &rwlock_Z2, &mutex_Z2, &rwsem_Z2);
134 }
135
136 /*
137 * For spinlocks and rwlocks we also do hardirq-safe / softirq-safe tests.
138 * The following functions use a lock from a simulated hardirq/softirq
139 * context, causing the locks to be marked as hardirq-safe/softirq-safe:
140 */
141
142 #define HARDIRQ_DISABLE local_irq_disable
143 #define HARDIRQ_ENABLE local_irq_enable
144
145 #define HARDIRQ_ENTER() \
146 local_irq_disable(); \
147 irq_enter(); \
148 WARN_ON(!in_irq());
149
150 #define HARDIRQ_EXIT() \
151 __irq_exit(); \
152 local_irq_enable();
153
154 #define SOFTIRQ_DISABLE local_bh_disable
155 #define SOFTIRQ_ENABLE local_bh_enable
156
157 #define SOFTIRQ_ENTER() \
158 local_bh_disable(); \
159 local_irq_disable(); \
160 trace_softirq_enter(); \
161 WARN_ON(!in_softirq());
162
163 #define SOFTIRQ_EXIT() \
164 trace_softirq_exit(); \
165 local_irq_enable(); \
166 local_bh_enable();
167
168 /*
169 * Shortcuts for lock/unlock API variants, to keep
170 * the testcases compact:
171 */
172 #define L(x) spin_lock(&lock_##x)
173 #define U(x) spin_unlock(&lock_##x)
174 #define LU(x) L(x); U(x)
175 #define SI(x) spin_lock_init(&lock_##x)
176
177 #define WL(x) write_lock(&rwlock_##x)
178 #define WU(x) write_unlock(&rwlock_##x)
179 #define WLU(x) WL(x); WU(x)
180
181 #define RL(x) read_lock(&rwlock_##x)
182 #define RU(x) read_unlock(&rwlock_##x)
183 #define RLU(x) RL(x); RU(x)
184 #define RWI(x) rwlock_init(&rwlock_##x)
185
186 #define ML(x) mutex_lock(&mutex_##x)
187 #define MU(x) mutex_unlock(&mutex_##x)
188 #define MI(x) mutex_init(&mutex_##x)
189
190 #define WSL(x) down_write(&rwsem_##x)
191 #define WSU(x) up_write(&rwsem_##x)
192
193 #define RSL(x) down_read(&rwsem_##x)
194 #define RSU(x) up_read(&rwsem_##x)
195 #define RWSI(x) init_rwsem(&rwsem_##x)
196
197 #define LOCK_UNLOCK_2(x,y) LOCK(x); LOCK(y); UNLOCK(y); UNLOCK(x)
198
199 /*
200 * Generate different permutations of the same testcase, using
201 * the same basic lock-dependency/state events:
202 */
203
204 #define GENERATE_TESTCASE(name) \
205 \
206 static void name(void) { E(); }
207
208 #define GENERATE_PERMUTATIONS_2_EVENTS(name) \
209 \
210 static void name##_12(void) { E1(); E2(); } \
211 static void name##_21(void) { E2(); E1(); }
212
213 #define GENERATE_PERMUTATIONS_3_EVENTS(name) \
214 \
215 static void name##_123(void) { E1(); E2(); E3(); } \
216 static void name##_132(void) { E1(); E3(); E2(); } \
217 static void name##_213(void) { E2(); E1(); E3(); } \
218 static void name##_231(void) { E2(); E3(); E1(); } \
219 static void name##_312(void) { E3(); E1(); E2(); } \
220 static void name##_321(void) { E3(); E2(); E1(); }
221
222 /*
223 * AA deadlock:
224 */
225
226 #define E() \
227 \
228 LOCK(X1); \
229 LOCK(X2); /* this one should fail */
230
231 /*
232 * 6 testcases:
233 */
234 #include "locking-selftest-spin.h"
235 GENERATE_TESTCASE(AA_spin)
236 #include "locking-selftest-wlock.h"
GENERATE_TESTCASE(AA_wlock)237 GENERATE_TESTCASE(AA_wlock)
238 #include "locking-selftest-rlock.h"
239 GENERATE_TESTCASE(AA_rlock)
240 #include "locking-selftest-mutex.h"
241 GENERATE_TESTCASE(AA_mutex)
242 #include "locking-selftest-wsem.h"
243 GENERATE_TESTCASE(AA_wsem)
244 #include "locking-selftest-rsem.h"
245 GENERATE_TESTCASE(AA_rsem)
246
247 #undef E
248
249 /*
250 * Special-case for read-locking, they are
251 * allowed to recurse on the same lock class:
252 */
253 static void rlock_AA1(void)
254 {
255 RL(X1);
256 RL(X1); // this one should NOT fail
257 }
258
rlock_AA1B(void)259 static void rlock_AA1B(void)
260 {
261 RL(X1);
262 RL(X2); // this one should NOT fail
263 }
264
rsem_AA1(void)265 static void rsem_AA1(void)
266 {
267 RSL(X1);
268 RSL(X1); // this one should fail
269 }
270
rsem_AA1B(void)271 static void rsem_AA1B(void)
272 {
273 RSL(X1);
274 RSL(X2); // this one should fail
275 }
276 /*
277 * The mixing of read and write locks is not allowed:
278 */
rlock_AA2(void)279 static void rlock_AA2(void)
280 {
281 RL(X1);
282 WL(X2); // this one should fail
283 }
284
rsem_AA2(void)285 static void rsem_AA2(void)
286 {
287 RSL(X1);
288 WSL(X2); // this one should fail
289 }
290
rlock_AA3(void)291 static void rlock_AA3(void)
292 {
293 WL(X1);
294 RL(X2); // this one should fail
295 }
296
rsem_AA3(void)297 static void rsem_AA3(void)
298 {
299 WSL(X1);
300 RSL(X2); // this one should fail
301 }
302
303 /*
304 * ABBA deadlock:
305 */
306
307 #define E() \
308 \
309 LOCK_UNLOCK_2(A, B); \
310 LOCK_UNLOCK_2(B, A); /* fail */
311
312 /*
313 * 6 testcases:
314 */
315 #include "locking-selftest-spin.h"
316 GENERATE_TESTCASE(ABBA_spin)
317 #include "locking-selftest-wlock.h"
GENERATE_TESTCASE(ABBA_wlock)318 GENERATE_TESTCASE(ABBA_wlock)
319 #include "locking-selftest-rlock.h"
320 GENERATE_TESTCASE(ABBA_rlock)
321 #include "locking-selftest-mutex.h"
322 GENERATE_TESTCASE(ABBA_mutex)
323 #include "locking-selftest-wsem.h"
324 GENERATE_TESTCASE(ABBA_wsem)
325 #include "locking-selftest-rsem.h"
326 GENERATE_TESTCASE(ABBA_rsem)
327
328 #undef E
329
330 /*
331 * AB BC CA deadlock:
332 */
333
334 #define E() \
335 \
336 LOCK_UNLOCK_2(A, B); \
337 LOCK_UNLOCK_2(B, C); \
338 LOCK_UNLOCK_2(C, A); /* fail */
339
340 /*
341 * 6 testcases:
342 */
343 #include "locking-selftest-spin.h"
344 GENERATE_TESTCASE(ABBCCA_spin)
345 #include "locking-selftest-wlock.h"
346 GENERATE_TESTCASE(ABBCCA_wlock)
347 #include "locking-selftest-rlock.h"
348 GENERATE_TESTCASE(ABBCCA_rlock)
349 #include "locking-selftest-mutex.h"
350 GENERATE_TESTCASE(ABBCCA_mutex)
351 #include "locking-selftest-wsem.h"
352 GENERATE_TESTCASE(ABBCCA_wsem)
353 #include "locking-selftest-rsem.h"
354 GENERATE_TESTCASE(ABBCCA_rsem)
355
356 #undef E
357
358 /*
359 * AB CA BC deadlock:
360 */
361
362 #define E() \
363 \
364 LOCK_UNLOCK_2(A, B); \
365 LOCK_UNLOCK_2(C, A); \
366 LOCK_UNLOCK_2(B, C); /* fail */
367
368 /*
369 * 6 testcases:
370 */
371 #include "locking-selftest-spin.h"
372 GENERATE_TESTCASE(ABCABC_spin)
373 #include "locking-selftest-wlock.h"
374 GENERATE_TESTCASE(ABCABC_wlock)
375 #include "locking-selftest-rlock.h"
376 GENERATE_TESTCASE(ABCABC_rlock)
377 #include "locking-selftest-mutex.h"
378 GENERATE_TESTCASE(ABCABC_mutex)
379 #include "locking-selftest-wsem.h"
380 GENERATE_TESTCASE(ABCABC_wsem)
381 #include "locking-selftest-rsem.h"
382 GENERATE_TESTCASE(ABCABC_rsem)
383
384 #undef E
385
386 /*
387 * AB BC CD DA deadlock:
388 */
389
390 #define E() \
391 \
392 LOCK_UNLOCK_2(A, B); \
393 LOCK_UNLOCK_2(B, C); \
394 LOCK_UNLOCK_2(C, D); \
395 LOCK_UNLOCK_2(D, A); /* fail */
396
397 /*
398 * 6 testcases:
399 */
400 #include "locking-selftest-spin.h"
401 GENERATE_TESTCASE(ABBCCDDA_spin)
402 #include "locking-selftest-wlock.h"
403 GENERATE_TESTCASE(ABBCCDDA_wlock)
404 #include "locking-selftest-rlock.h"
405 GENERATE_TESTCASE(ABBCCDDA_rlock)
406 #include "locking-selftest-mutex.h"
407 GENERATE_TESTCASE(ABBCCDDA_mutex)
408 #include "locking-selftest-wsem.h"
409 GENERATE_TESTCASE(ABBCCDDA_wsem)
410 #include "locking-selftest-rsem.h"
411 GENERATE_TESTCASE(ABBCCDDA_rsem)
412
413 #undef E
414
415 /*
416 * AB CD BD DA deadlock:
417 */
418 #define E() \
419 \
420 LOCK_UNLOCK_2(A, B); \
421 LOCK_UNLOCK_2(C, D); \
422 LOCK_UNLOCK_2(B, D); \
423 LOCK_UNLOCK_2(D, A); /* fail */
424
425 /*
426 * 6 testcases:
427 */
428 #include "locking-selftest-spin.h"
429 GENERATE_TESTCASE(ABCDBDDA_spin)
430 #include "locking-selftest-wlock.h"
431 GENERATE_TESTCASE(ABCDBDDA_wlock)
432 #include "locking-selftest-rlock.h"
433 GENERATE_TESTCASE(ABCDBDDA_rlock)
434 #include "locking-selftest-mutex.h"
435 GENERATE_TESTCASE(ABCDBDDA_mutex)
436 #include "locking-selftest-wsem.h"
437 GENERATE_TESTCASE(ABCDBDDA_wsem)
438 #include "locking-selftest-rsem.h"
439 GENERATE_TESTCASE(ABCDBDDA_rsem)
440
441 #undef E
442
443 /*
444 * AB CD BC DA deadlock:
445 */
446 #define E() \
447 \
448 LOCK_UNLOCK_2(A, B); \
449 LOCK_UNLOCK_2(C, D); \
450 LOCK_UNLOCK_2(B, C); \
451 LOCK_UNLOCK_2(D, A); /* fail */
452
453 /*
454 * 6 testcases:
455 */
456 #include "locking-selftest-spin.h"
457 GENERATE_TESTCASE(ABCDBCDA_spin)
458 #include "locking-selftest-wlock.h"
459 GENERATE_TESTCASE(ABCDBCDA_wlock)
460 #include "locking-selftest-rlock.h"
461 GENERATE_TESTCASE(ABCDBCDA_rlock)
462 #include "locking-selftest-mutex.h"
463 GENERATE_TESTCASE(ABCDBCDA_mutex)
464 #include "locking-selftest-wsem.h"
465 GENERATE_TESTCASE(ABCDBCDA_wsem)
466 #include "locking-selftest-rsem.h"
467 GENERATE_TESTCASE(ABCDBCDA_rsem)
468
469 #undef E
470
471 /*
472 * Double unlock:
473 */
474 #define E() \
475 \
476 LOCK(A); \
477 UNLOCK(A); \
478 UNLOCK(A); /* fail */
479
480 /*
481 * 6 testcases:
482 */
483 #include "locking-selftest-spin.h"
484 GENERATE_TESTCASE(double_unlock_spin)
485 #include "locking-selftest-wlock.h"
486 GENERATE_TESTCASE(double_unlock_wlock)
487 #include "locking-selftest-rlock.h"
488 GENERATE_TESTCASE(double_unlock_rlock)
489 #include "locking-selftest-mutex.h"
490 GENERATE_TESTCASE(double_unlock_mutex)
491 #include "locking-selftest-wsem.h"
492 GENERATE_TESTCASE(double_unlock_wsem)
493 #include "locking-selftest-rsem.h"
494 GENERATE_TESTCASE(double_unlock_rsem)
495
496 #undef E
497
498 /*
499 * Bad unlock ordering:
500 */
501 #define E() \
502 \
503 LOCK(A); \
504 LOCK(B); \
505 UNLOCK(A); /* fail */ \
506 UNLOCK(B);
507
508 /*
509 * 6 testcases:
510 */
511 #include "locking-selftest-spin.h"
512 GENERATE_TESTCASE(bad_unlock_order_spin)
513 #include "locking-selftest-wlock.h"
514 GENERATE_TESTCASE(bad_unlock_order_wlock)
515 #include "locking-selftest-rlock.h"
516 GENERATE_TESTCASE(bad_unlock_order_rlock)
517 #include "locking-selftest-mutex.h"
518 GENERATE_TESTCASE(bad_unlock_order_mutex)
519 #include "locking-selftest-wsem.h"
520 GENERATE_TESTCASE(bad_unlock_order_wsem)
521 #include "locking-selftest-rsem.h"
522 GENERATE_TESTCASE(bad_unlock_order_rsem)
523
524 #undef E
525
526 /*
527 * initializing a held lock:
528 */
529 #define E() \
530 \
531 LOCK(A); \
532 INIT(A); /* fail */
533
534 /*
535 * 6 testcases:
536 */
537 #include "locking-selftest-spin.h"
538 GENERATE_TESTCASE(init_held_spin)
539 #include "locking-selftest-wlock.h"
540 GENERATE_TESTCASE(init_held_wlock)
541 #include "locking-selftest-rlock.h"
542 GENERATE_TESTCASE(init_held_rlock)
543 #include "locking-selftest-mutex.h"
544 GENERATE_TESTCASE(init_held_mutex)
545 #include "locking-selftest-wsem.h"
546 GENERATE_TESTCASE(init_held_wsem)
547 #include "locking-selftest-rsem.h"
548 GENERATE_TESTCASE(init_held_rsem)
549
550 #undef E
551
552 /*
553 * locking an irq-safe lock with irqs enabled:
554 */
555 #define E1() \
556 \
557 IRQ_ENTER(); \
558 LOCK(A); \
559 UNLOCK(A); \
560 IRQ_EXIT();
561
562 #define E2() \
563 \
564 LOCK(A); \
565 UNLOCK(A);
566
567 /*
568 * Generate 24 testcases:
569 */
570 #include "locking-selftest-spin-hardirq.h"
571 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
572
573 #include "locking-selftest-rlock-hardirq.h"
574 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
575
576 #include "locking-selftest-wlock-hardirq.h"
577 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_wlock)
578
579 #include "locking-selftest-spin-softirq.h"
580 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_spin)
581
582 #include "locking-selftest-rlock-softirq.h"
583 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock)
584
585 #include "locking-selftest-wlock-softirq.h"
586 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock)
587
588 #undef E1
589 #undef E2
590
591 /*
592 * Enabling hardirqs with a softirq-safe lock held:
593 */
594 #define E1() \
595 \
596 SOFTIRQ_ENTER(); \
597 LOCK(A); \
598 UNLOCK(A); \
599 SOFTIRQ_EXIT();
600
601 #define E2() \
602 \
603 HARDIRQ_DISABLE(); \
604 LOCK(A); \
605 HARDIRQ_ENABLE(); \
606 UNLOCK(A);
607
608 /*
609 * Generate 12 testcases:
610 */
611 #include "locking-selftest-spin.h"
612 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_spin)
613
614 #include "locking-selftest-wlock.h"
615 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_wlock)
616
617 #include "locking-selftest-rlock.h"
618 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
619
620 #undef E1
621 #undef E2
622
623 /*
624 * Enabling irqs with an irq-safe lock held:
625 */
626 #define E1() \
627 \
628 IRQ_ENTER(); \
629 LOCK(A); \
630 UNLOCK(A); \
631 IRQ_EXIT();
632
633 #define E2() \
634 \
635 IRQ_DISABLE(); \
636 LOCK(A); \
637 IRQ_ENABLE(); \
638 UNLOCK(A);
639
640 /*
641 * Generate 24 testcases:
642 */
643 #include "locking-selftest-spin-hardirq.h"
644 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
645
646 #include "locking-selftest-rlock-hardirq.h"
647 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
648
649 #include "locking-selftest-wlock-hardirq.h"
650 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_wlock)
651
652 #include "locking-selftest-spin-softirq.h"
653 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_spin)
654
655 #include "locking-selftest-rlock-softirq.h"
656 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock)
657
658 #include "locking-selftest-wlock-softirq.h"
659 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
660
661 #undef E1
662 #undef E2
663
664 /*
665 * Acquiring a irq-unsafe lock while holding an irq-safe-lock:
666 */
667 #define E1() \
668 \
669 LOCK(A); \
670 LOCK(B); \
671 UNLOCK(B); \
672 UNLOCK(A); \
673
674 #define E2() \
675 \
676 LOCK(B); \
677 UNLOCK(B);
678
679 #define E3() \
680 \
681 IRQ_ENTER(); \
682 LOCK(A); \
683 UNLOCK(A); \
684 IRQ_EXIT();
685
686 /*
687 * Generate 36 testcases:
688 */
689 #include "locking-selftest-spin-hardirq.h"
690 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
691
692 #include "locking-selftest-rlock-hardirq.h"
693 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
694
695 #include "locking-selftest-wlock-hardirq.h"
696 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_wlock)
697
698 #include "locking-selftest-spin-softirq.h"
699 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_spin)
700
701 #include "locking-selftest-rlock-softirq.h"
702 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock)
703
704 #include "locking-selftest-wlock-softirq.h"
705 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
706
707 #undef E1
708 #undef E2
709 #undef E3
710
711 /*
712 * If a lock turns into softirq-safe, but earlier it took
713 * a softirq-unsafe lock:
714 */
715
716 #define E1() \
717 IRQ_DISABLE(); \
718 LOCK(A); \
719 LOCK(B); \
720 UNLOCK(B); \
721 UNLOCK(A); \
722 IRQ_ENABLE();
723
724 #define E2() \
725 LOCK(B); \
726 UNLOCK(B);
727
728 #define E3() \
729 IRQ_ENTER(); \
730 LOCK(A); \
731 UNLOCK(A); \
732 IRQ_EXIT();
733
734 /*
735 * Generate 36 testcases:
736 */
737 #include "locking-selftest-spin-hardirq.h"
738 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
739
740 #include "locking-selftest-rlock-hardirq.h"
741 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
742
743 #include "locking-selftest-wlock-hardirq.h"
744 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_wlock)
745
746 #include "locking-selftest-spin-softirq.h"
747 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_spin)
748
749 #include "locking-selftest-rlock-softirq.h"
750 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock)
751
752 #include "locking-selftest-wlock-softirq.h"
753 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)
754
755 #undef E1
756 #undef E2
757 #undef E3
758
759 /*
760 * read-lock / write-lock irq inversion.
761 *
762 * Deadlock scenario:
763 *
764 * CPU#1 is at #1, i.e. it has write-locked A, but has not
765 * taken B yet.
766 *
767 * CPU#2 is at #2, i.e. it has locked B.
768 *
769 * Hardirq hits CPU#2 at point #2 and is trying to read-lock A.
770 *
771 * The deadlock occurs because CPU#1 will spin on B, and CPU#2
772 * will spin on A.
773 */
774
775 #define E1() \
776 \
777 IRQ_DISABLE(); \
778 WL(A); \
779 LOCK(B); \
780 UNLOCK(B); \
781 WU(A); \
782 IRQ_ENABLE();
783
784 #define E2() \
785 \
786 LOCK(B); \
787 UNLOCK(B);
788
789 #define E3() \
790 \
791 IRQ_ENTER(); \
792 RL(A); \
793 RU(A); \
794 IRQ_EXIT();
795
796 /*
797 * Generate 36 testcases:
798 */
799 #include "locking-selftest-spin-hardirq.h"
800 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_spin)
801
802 #include "locking-selftest-rlock-hardirq.h"
803 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_rlock)
804
805 #include "locking-selftest-wlock-hardirq.h"
806 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_wlock)
807
808 #include "locking-selftest-spin-softirq.h"
809 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_spin)
810
811 #include "locking-selftest-rlock-softirq.h"
812 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_rlock)
813
814 #include "locking-selftest-wlock-softirq.h"
815 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_wlock)
816
817 #undef E1
818 #undef E2
819 #undef E3
820
821 /*
822 * read-lock / write-lock recursion that is actually safe.
823 */
824
825 #define E1() \
826 \
827 IRQ_DISABLE(); \
828 WL(A); \
829 WU(A); \
830 IRQ_ENABLE();
831
832 #define E2() \
833 \
834 RL(A); \
835 RU(A); \
836
837 #define E3() \
838 \
839 IRQ_ENTER(); \
840 RL(A); \
841 L(B); \
842 U(B); \
843 RU(A); \
844 IRQ_EXIT();
845
846 /*
847 * Generate 12 testcases:
848 */
849 #include "locking-selftest-hardirq.h"
850 GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_hard)
851
852 #include "locking-selftest-softirq.h"
853 GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
854
855 #undef E1
856 #undef E2
857 #undef E3
858
859 /*
860 * read-lock / write-lock recursion that is unsafe.
861 */
862
863 #define E1() \
864 \
865 IRQ_DISABLE(); \
866 L(B); \
867 WL(A); \
868 WU(A); \
869 U(B); \
870 IRQ_ENABLE();
871
872 #define E2() \
873 \
874 RL(A); \
875 RU(A); \
876
877 #define E3() \
878 \
879 IRQ_ENTER(); \
880 L(B); \
881 U(B); \
882 IRQ_EXIT();
883
884 /*
885 * Generate 12 testcases:
886 */
887 #include "locking-selftest-hardirq.h"
888 // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_hard)
889
890 #include "locking-selftest-softirq.h"
891 // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_soft)
892
893 #ifdef CONFIG_DEBUG_LOCK_ALLOC
894 # define I_SPINLOCK(x) lockdep_reset_lock(&lock_##x.dep_map)
895 # define I_RWLOCK(x) lockdep_reset_lock(&rwlock_##x.dep_map)
896 # define I_MUTEX(x) lockdep_reset_lock(&mutex_##x.dep_map)
897 # define I_RWSEM(x) lockdep_reset_lock(&rwsem_##x.dep_map)
898 #else
899 # define I_SPINLOCK(x)
900 # define I_RWLOCK(x)
901 # define I_MUTEX(x)
902 # define I_RWSEM(x)
903 #endif
904
905 #define I1(x) \
906 do { \
907 I_SPINLOCK(x); \
908 I_RWLOCK(x); \
909 I_MUTEX(x); \
910 I_RWSEM(x); \
911 } while (0)
912
913 #define I2(x) \
914 do { \
915 spin_lock_init(&lock_##x); \
916 rwlock_init(&rwlock_##x); \
917 mutex_init(&mutex_##x); \
918 init_rwsem(&rwsem_##x); \
919 } while (0)
920
921 static void reset_locks(void)
922 {
923 local_irq_disable();
924 I1(A); I1(B); I1(C); I1(D);
925 I1(X1); I1(X2); I1(Y1); I1(Y2); I1(Z1); I1(Z2);
926 lockdep_reset();
927 I2(A); I2(B); I2(C); I2(D);
928 init_shared_classes();
929 local_irq_enable();
930 }
931
932 #undef I
933
934 static int testcase_total;
935 static int testcase_successes;
936 static int expected_testcase_failures;
937 static int unexpected_testcase_failures;
938
dotest(void (* testcase_fn)(void),int expected,int lockclass_mask)939 static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
940 {
941 unsigned long saved_preempt_count = preempt_count();
942 int expected_failure = 0;
943
944 WARN_ON(irqs_disabled());
945
946 testcase_fn();
947 /*
948 * Filter out expected failures:
949 */
950 #ifndef CONFIG_PROVE_LOCKING
951 if ((lockclass_mask & LOCKTYPE_SPIN) && debug_locks != expected)
952 expected_failure = 1;
953 if ((lockclass_mask & LOCKTYPE_RWLOCK) && debug_locks != expected)
954 expected_failure = 1;
955 if ((lockclass_mask & LOCKTYPE_MUTEX) && debug_locks != expected)
956 expected_failure = 1;
957 if ((lockclass_mask & LOCKTYPE_RWSEM) && debug_locks != expected)
958 expected_failure = 1;
959 #endif
960 if (debug_locks != expected) {
961 if (expected_failure) {
962 expected_testcase_failures++;
963 printk("failed|");
964 } else {
965 unexpected_testcase_failures++;
966
967 printk("FAILED|");
968 dump_stack();
969 }
970 } else {
971 testcase_successes++;
972 printk(" ok |");
973 }
974 testcase_total++;
975
976 if (debug_locks_verbose)
977 printk(" lockclass mask: %x, debug_locks: %d, expected: %d\n",
978 lockclass_mask, debug_locks, expected);
979 /*
980 * Some tests (e.g. double-unlock) might corrupt the preemption
981 * count, so restore it:
982 */
983 preempt_count() = saved_preempt_count;
984 #ifdef CONFIG_TRACE_IRQFLAGS
985 if (softirq_count())
986 current->softirqs_enabled = 0;
987 else
988 current->softirqs_enabled = 1;
989 #endif
990
991 reset_locks();
992 }
993
print_testname(const char * testname)994 static inline void print_testname(const char *testname)
995 {
996 printk("%33s:", testname);
997 }
998
999 #define DO_TESTCASE_1(desc, name, nr) \
1000 print_testname(desc"/"#nr); \
1001 dotest(name##_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1002 printk("\n");
1003
1004 #define DO_TESTCASE_1B(desc, name, nr) \
1005 print_testname(desc"/"#nr); \
1006 dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1007 printk("\n");
1008
1009 #define DO_TESTCASE_3(desc, name, nr) \
1010 print_testname(desc"/"#nr); \
1011 dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN); \
1012 dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1013 dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1014 printk("\n");
1015
1016 #define DO_TESTCASE_3RW(desc, name, nr) \
1017 print_testname(desc"/"#nr); \
1018 dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN|LOCKTYPE_RWLOCK);\
1019 dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1020 dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1021 printk("\n");
1022
1023 #define DO_TESTCASE_6(desc, name) \
1024 print_testname(desc); \
1025 dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \
1026 dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \
1027 dotest(name##_rlock, FAILURE, LOCKTYPE_RWLOCK); \
1028 dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \
1029 dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \
1030 dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \
1031 printk("\n");
1032
1033 #define DO_TESTCASE_6_SUCCESS(desc, name) \
1034 print_testname(desc); \
1035 dotest(name##_spin, SUCCESS, LOCKTYPE_SPIN); \
1036 dotest(name##_wlock, SUCCESS, LOCKTYPE_RWLOCK); \
1037 dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \
1038 dotest(name##_mutex, SUCCESS, LOCKTYPE_MUTEX); \
1039 dotest(name##_wsem, SUCCESS, LOCKTYPE_RWSEM); \
1040 dotest(name##_rsem, SUCCESS, LOCKTYPE_RWSEM); \
1041 printk("\n");
1042
1043 /*
1044 * 'read' variant: rlocks must not trigger.
1045 */
1046 #define DO_TESTCASE_6R(desc, name) \
1047 print_testname(desc); \
1048 dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \
1049 dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \
1050 dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \
1051 dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \
1052 dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \
1053 dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \
1054 printk("\n");
1055
1056 #define DO_TESTCASE_2I(desc, name, nr) \
1057 DO_TESTCASE_1("hard-"desc, name##_hard, nr); \
1058 DO_TESTCASE_1("soft-"desc, name##_soft, nr);
1059
1060 #define DO_TESTCASE_2IB(desc, name, nr) \
1061 DO_TESTCASE_1B("hard-"desc, name##_hard, nr); \
1062 DO_TESTCASE_1B("soft-"desc, name##_soft, nr);
1063
1064 #define DO_TESTCASE_6I(desc, name, nr) \
1065 DO_TESTCASE_3("hard-"desc, name##_hard, nr); \
1066 DO_TESTCASE_3("soft-"desc, name##_soft, nr);
1067
1068 #define DO_TESTCASE_6IRW(desc, name, nr) \
1069 DO_TESTCASE_3RW("hard-"desc, name##_hard, nr); \
1070 DO_TESTCASE_3RW("soft-"desc, name##_soft, nr);
1071
1072 #define DO_TESTCASE_2x3(desc, name) \
1073 DO_TESTCASE_3(desc, name, 12); \
1074 DO_TESTCASE_3(desc, name, 21);
1075
1076 #define DO_TESTCASE_2x6(desc, name) \
1077 DO_TESTCASE_6I(desc, name, 12); \
1078 DO_TESTCASE_6I(desc, name, 21);
1079
1080 #define DO_TESTCASE_6x2(desc, name) \
1081 DO_TESTCASE_2I(desc, name, 123); \
1082 DO_TESTCASE_2I(desc, name, 132); \
1083 DO_TESTCASE_2I(desc, name, 213); \
1084 DO_TESTCASE_2I(desc, name, 231); \
1085 DO_TESTCASE_2I(desc, name, 312); \
1086 DO_TESTCASE_2I(desc, name, 321);
1087
1088 #define DO_TESTCASE_6x2B(desc, name) \
1089 DO_TESTCASE_2IB(desc, name, 123); \
1090 DO_TESTCASE_2IB(desc, name, 132); \
1091 DO_TESTCASE_2IB(desc, name, 213); \
1092 DO_TESTCASE_2IB(desc, name, 231); \
1093 DO_TESTCASE_2IB(desc, name, 312); \
1094 DO_TESTCASE_2IB(desc, name, 321);
1095
1096 #define DO_TESTCASE_6x6(desc, name) \
1097 DO_TESTCASE_6I(desc, name, 123); \
1098 DO_TESTCASE_6I(desc, name, 132); \
1099 DO_TESTCASE_6I(desc, name, 213); \
1100 DO_TESTCASE_6I(desc, name, 231); \
1101 DO_TESTCASE_6I(desc, name, 312); \
1102 DO_TESTCASE_6I(desc, name, 321);
1103
1104 #define DO_TESTCASE_6x6RW(desc, name) \
1105 DO_TESTCASE_6IRW(desc, name, 123); \
1106 DO_TESTCASE_6IRW(desc, name, 132); \
1107 DO_TESTCASE_6IRW(desc, name, 213); \
1108 DO_TESTCASE_6IRW(desc, name, 231); \
1109 DO_TESTCASE_6IRW(desc, name, 312); \
1110 DO_TESTCASE_6IRW(desc, name, 321);
1111
1112
locking_selftest(void)1113 void locking_selftest(void)
1114 {
1115 /*
1116 * Got a locking failure before the selftest ran?
1117 */
1118 if (!debug_locks) {
1119 printk("----------------------------------\n");
1120 printk("| Locking API testsuite disabled |\n");
1121 printk("----------------------------------\n");
1122 return;
1123 }
1124
1125 /*
1126 * Run the testsuite:
1127 */
1128 printk("------------------------\n");
1129 printk("| Locking API testsuite:\n");
1130 printk("----------------------------------------------------------------------------\n");
1131 printk(" | spin |wlock |rlock |mutex | wsem | rsem |\n");
1132 printk(" --------------------------------------------------------------------------\n");
1133
1134 init_shared_classes();
1135 debug_locks_silent = !debug_locks_verbose;
1136
1137 DO_TESTCASE_6R("A-A deadlock", AA);
1138 DO_TESTCASE_6R("A-B-B-A deadlock", ABBA);
1139 DO_TESTCASE_6R("A-B-B-C-C-A deadlock", ABBCCA);
1140 DO_TESTCASE_6R("A-B-C-A-B-C deadlock", ABCABC);
1141 DO_TESTCASE_6R("A-B-B-C-C-D-D-A deadlock", ABBCCDDA);
1142 DO_TESTCASE_6R("A-B-C-D-B-D-D-A deadlock", ABCDBDDA);
1143 DO_TESTCASE_6R("A-B-C-D-B-C-D-A deadlock", ABCDBCDA);
1144 DO_TESTCASE_6("double unlock", double_unlock);
1145 DO_TESTCASE_6("initialize held", init_held);
1146 DO_TESTCASE_6_SUCCESS("bad unlock order", bad_unlock_order);
1147
1148 printk(" --------------------------------------------------------------------------\n");
1149 print_testname("recursive read-lock");
1150 printk(" |");
1151 dotest(rlock_AA1, SUCCESS, LOCKTYPE_RWLOCK);
1152 printk(" |");
1153 dotest(rsem_AA1, FAILURE, LOCKTYPE_RWSEM);
1154 printk("\n");
1155
1156 print_testname("recursive read-lock #2");
1157 printk(" |");
1158 dotest(rlock_AA1B, SUCCESS, LOCKTYPE_RWLOCK);
1159 printk(" |");
1160 dotest(rsem_AA1B, FAILURE, LOCKTYPE_RWSEM);
1161 printk("\n");
1162
1163 print_testname("mixed read-write-lock");
1164 printk(" |");
1165 dotest(rlock_AA2, FAILURE, LOCKTYPE_RWLOCK);
1166 printk(" |");
1167 dotest(rsem_AA2, FAILURE, LOCKTYPE_RWSEM);
1168 printk("\n");
1169
1170 print_testname("mixed write-read-lock");
1171 printk(" |");
1172 dotest(rlock_AA3, FAILURE, LOCKTYPE_RWLOCK);
1173 printk(" |");
1174 dotest(rsem_AA3, FAILURE, LOCKTYPE_RWSEM);
1175 printk("\n");
1176
1177 printk(" --------------------------------------------------------------------------\n");
1178
1179 /*
1180 * irq-context testcases:
1181 */
1182 DO_TESTCASE_2x6("irqs-on + irq-safe-A", irqsafe1);
1183 DO_TESTCASE_2x3("sirq-safe-A => hirqs-on", irqsafe2A);
1184 DO_TESTCASE_2x6("safe-A + irqs-on", irqsafe2B);
1185 DO_TESTCASE_6x6("safe-A + unsafe-B #1", irqsafe3);
1186 DO_TESTCASE_6x6("safe-A + unsafe-B #2", irqsafe4);
1187 DO_TESTCASE_6x6RW("irq lock-inversion", irq_inversion);
1188
1189 DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
1190 // DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);
1191
1192 if (unexpected_testcase_failures) {
1193 printk("-----------------------------------------------------------------\n");
1194 debug_locks = 0;
1195 printk("BUG: %3d unexpected failures (out of %3d) - debugging disabled! |\n",
1196 unexpected_testcase_failures, testcase_total);
1197 printk("-----------------------------------------------------------------\n");
1198 } else if (expected_testcase_failures && testcase_successes) {
1199 printk("--------------------------------------------------------\n");
1200 printk("%3d out of %3d testcases failed, as expected. |\n",
1201 expected_testcase_failures, testcase_total);
1202 printk("----------------------------------------------------\n");
1203 debug_locks = 1;
1204 } else if (expected_testcase_failures && !testcase_successes) {
1205 printk("--------------------------------------------------------\n");
1206 printk("All %3d testcases failed, as expected. |\n",
1207 expected_testcase_failures);
1208 printk("----------------------------------------\n");
1209 debug_locks = 1;
1210 } else {
1211 printk("-------------------------------------------------------\n");
1212 printk("Good, all %3d testcases passed! |\n",
1213 testcase_successes);
1214 printk("---------------------------------\n");
1215 debug_locks = 1;
1216 }
1217 debug_locks_silent = 0;
1218 }
1219