net: l2tp_eth: fix kernel panic on rmmod l2tp_eth
[pandora-kernel.git] / lib / locking-selftest.c
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
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)
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"
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
258 static void rlock_AA1B(void)
259 {
260         RL(X1);
261         RL(X2); // this one should NOT fail
262 }
263
264 static void rsem_AA1(void)
265 {
266         RSL(X1);
267         RSL(X1); // this one should fail
268 }
269
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  */
278 static void rlock_AA2(void)
279 {
280         RL(X1);
281         WL(X2); // this one should fail
282 }
283
284 static void rsem_AA2(void)
285 {
286         RSL(X1);
287         WSL(X2); // this one should fail
288 }
289
290 static void rlock_AA3(void)
291 {
292         WL(X1);
293         RL(X2); // this one should fail
294 }
295
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"
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
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
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
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 }