Initial commit
[cbs-scheduler.git] / lib / locking-selftest.c
blobb0532c5a9e4ecbb69ad2c52d36120f741e93f415
1 /*
2 * lib/locking-selftest.c
4 * Testsuite for various locking APIs: spinlocks, rwlocks,
5 * mutexes and rw-semaphores.
7 * It is checking both false positives and false negatives.
9 * Started by Ingo Molnar:
11 * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
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>
26 * Change this to 1 if you want to see the failure printouts:
28 static unsigned int debug_locks_verbose;
30 static int __init setup_debug_locks_verbose(char *str)
32 get_option(&str, &debug_locks_verbose);
34 return 1;
37 __setup("debug_locks_verbose=", setup_debug_locks_verbose);
39 #define FAILURE 0
40 #define SUCCESS 1
42 #define LOCKTYPE_SPIN 0x1
43 #define LOCKTYPE_RWLOCK 0x2
44 #define LOCKTYPE_MUTEX 0x4
45 #define LOCKTYPE_RWSEM 0x8
48 * Normal standalone locks, for the circular and irq-context
49 * dependency tests:
51 static DEFINE_SPINLOCK(lock_A);
52 static DEFINE_SPINLOCK(lock_B);
53 static DEFINE_SPINLOCK(lock_C);
54 static DEFINE_SPINLOCK(lock_D);
56 static DEFINE_RWLOCK(rwlock_A);
57 static DEFINE_RWLOCK(rwlock_B);
58 static DEFINE_RWLOCK(rwlock_C);
59 static DEFINE_RWLOCK(rwlock_D);
61 static DEFINE_MUTEX(mutex_A);
62 static DEFINE_MUTEX(mutex_B);
63 static DEFINE_MUTEX(mutex_C);
64 static DEFINE_MUTEX(mutex_D);
66 static DECLARE_RWSEM(rwsem_A);
67 static DECLARE_RWSEM(rwsem_B);
68 static DECLARE_RWSEM(rwsem_C);
69 static DECLARE_RWSEM(rwsem_D);
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:
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);
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);
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);
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);
106 * non-inlined runtime initializers, to let separate locks share
107 * the same lock-class:
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) \
114 spin_lock_init(lock); \
115 rwlock_init(rwlock); \
116 mutex_init(mutex); \
117 init_rwsem(rwsem); \
120 INIT_CLASS_FUNC(X)
121 INIT_CLASS_FUNC(Y)
122 INIT_CLASS_FUNC(Z)
124 static void init_shared_classes(void)
126 init_class_X(&lock_X1, &rwlock_X1, &mutex_X1, &rwsem_X1);
127 init_class_X(&lock_X2, &rwlock_X2, &mutex_X2, &rwsem_X2);
129 init_class_Y(&lock_Y1, &rwlock_Y1, &mutex_Y1, &rwsem_Y1);
130 init_class_Y(&lock_Y2, &rwlock_Y2, &mutex_Y2, &rwsem_Y2);
132 init_class_Z(&lock_Z1, &rwlock_Z1, &mutex_Z1, &rwsem_Z1);
133 init_class_Z(&lock_Z2, &rwlock_Z2, &mutex_Z2, &rwsem_Z2);
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:
142 #define HARDIRQ_DISABLE local_irq_disable
143 #define HARDIRQ_ENABLE local_irq_enable
145 #define HARDIRQ_ENTER() \
146 local_irq_disable(); \
147 irq_enter(); \
148 WARN_ON(!in_irq());
150 #define HARDIRQ_EXIT() \
151 __irq_exit(); \
152 local_irq_enable();
154 #define SOFTIRQ_DISABLE local_bh_disable
155 #define SOFTIRQ_ENABLE local_bh_enable
157 #define SOFTIRQ_ENTER() \
158 local_bh_disable(); \
159 local_irq_disable(); \
160 lockdep_softirq_enter(); \
161 /* FIXME: preemptible softirqs. WARN_ON(!in_softirq()); */
163 #define SOFTIRQ_EXIT() \
164 lockdep_softirq_exit(); \
165 local_irq_enable(); \
166 local_bh_enable();
169 * Shortcuts for lock/unlock API variants, to keep
170 * the testcases compact:
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)
177 #define WL(x) write_lock(&rwlock_##x)
178 #define WU(x) write_unlock(&rwlock_##x)
179 #define WLU(x) WL(x); WU(x)
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)
186 #define ML(x) mutex_lock(&mutex_##x)
187 #define MU(x) mutex_unlock(&mutex_##x)
188 #define MI(x) mutex_init(&mutex_##x)
190 #define WSL(x) down_write(&rwsem_##x)
191 #define WSU(x) up_write(&rwsem_##x)
193 #define RSL(x) down_read(&rwsem_##x)
194 #define RSU(x) up_read(&rwsem_##x)
195 #define RWSI(x) init_rwsem(&rwsem_##x)
197 #define LOCK_UNLOCK_2(x,y) LOCK(x); LOCK(y); UNLOCK(y); UNLOCK(x)
200 * Generate different permutations of the same testcase, using
201 * the same basic lock-dependency/state events:
204 #define GENERATE_TESTCASE(name) \
206 static void name(void) { E(); }
208 #define GENERATE_PERMUTATIONS_2_EVENTS(name) \
210 static void name##_12(void) { E1(); E2(); } \
211 static void name##_21(void) { E2(); E1(); }
213 #define GENERATE_PERMUTATIONS_3_EVENTS(name) \
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(); }
223 * AA deadlock:
226 #define E() \
228 LOCK(X1); \
229 LOCK(X2); /* this one should fail */
232 * 6 testcases:
234 #include "locking-selftest-spin.h"
235 GENERATE_TESTCASE(AA_spin)
236 #include "locking-selftest-wlock.h"
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)
247 #undef E
250 * Special-case for read-locking, they are
251 * allowed to recurse on the same lock class:
253 static void rlock_AA1(void)
255 RL(X1);
256 RL(X1); // this one should NOT fail
259 static void rlock_AA1B(void)
261 RL(X1);
262 RL(X2); // this one should NOT fail
265 static void rsem_AA1(void)
267 RSL(X1);
268 RSL(X1); // this one should fail
271 static void rsem_AA1B(void)
273 RSL(X1);
274 RSL(X2); // this one should fail
277 * The mixing of read and write locks is not allowed:
279 static void rlock_AA2(void)
281 RL(X1);
282 WL(X2); // this one should fail
285 static void rsem_AA2(void)
287 RSL(X1);
288 WSL(X2); // this one should fail
291 static void rlock_AA3(void)
293 WL(X1);
294 RL(X2); // this one should fail
297 static void rsem_AA3(void)
299 WSL(X1);
300 RSL(X2); // this one should fail
304 * ABBA deadlock:
307 #define E() \
309 LOCK_UNLOCK_2(A, B); \
310 LOCK_UNLOCK_2(B, A); /* fail */
313 * 6 testcases:
315 #include "locking-selftest-spin.h"
316 GENERATE_TESTCASE(ABBA_spin)
317 #include "locking-selftest-wlock.h"
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)
328 #undef E
331 * AB BC CA deadlock:
334 #define E() \
336 LOCK_UNLOCK_2(A, B); \
337 LOCK_UNLOCK_2(B, C); \
338 LOCK_UNLOCK_2(C, A); /* fail */
341 * 6 testcases:
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)
356 #undef E
359 * AB CA BC deadlock:
362 #define E() \
364 LOCK_UNLOCK_2(A, B); \
365 LOCK_UNLOCK_2(C, A); \
366 LOCK_UNLOCK_2(B, C); /* fail */
369 * 6 testcases:
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)
384 #undef E
387 * AB BC CD DA deadlock:
390 #define E() \
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 */
398 * 6 testcases:
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)
413 #undef E
416 * AB CD BD DA deadlock:
418 #define E() \
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 */
426 * 6 testcases:
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)
441 #undef E
444 * AB CD BC DA deadlock:
446 #define E() \
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 */
454 * 6 testcases:
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)
469 #undef E
472 * Double unlock:
474 #define E() \
476 LOCK(A); \
477 UNLOCK(A); \
478 UNLOCK(A); /* fail */
481 * 6 testcases:
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)
496 #undef E
499 * Bad unlock ordering:
501 #define E() \
503 LOCK(A); \
504 LOCK(B); \
505 UNLOCK(A); /* fail */ \
506 UNLOCK(B);
509 * 6 testcases:
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)
524 #undef E
527 * initializing a held lock:
529 #define E() \
531 LOCK(A); \
532 INIT(A); /* fail */
535 * 6 testcases:
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)
550 #undef E
553 * FIXME: turns these into raw-spinlock tests on -rt
555 #ifndef CONFIG_PREEMPT_RT
558 * locking an irq-safe lock with irqs enabled:
560 #define E1() \
562 IRQ_ENTER(); \
563 LOCK(A); \
564 UNLOCK(A); \
565 IRQ_EXIT();
567 #define E2() \
569 LOCK(A); \
570 UNLOCK(A);
573 * Generate 24 testcases:
575 #include "locking-selftest-spin-hardirq.h"
576 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin)
578 #include "locking-selftest-rlock-hardirq.h"
579 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock)
581 #include "locking-selftest-wlock-hardirq.h"
582 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_wlock)
584 #include "locking-selftest-spin-softirq.h"
585 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_spin)
587 #include "locking-selftest-rlock-softirq.h"
588 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock)
590 #include "locking-selftest-wlock-softirq.h"
591 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock)
593 #undef E1
594 #undef E2
597 * Enabling hardirqs with a softirq-safe lock held:
599 #define E1() \
601 SOFTIRQ_ENTER(); \
602 LOCK(A); \
603 UNLOCK(A); \
604 SOFTIRQ_EXIT();
606 #define E2() \
608 HARDIRQ_DISABLE(); \
609 LOCK(A); \
610 HARDIRQ_ENABLE(); \
611 UNLOCK(A);
614 * Generate 12 testcases:
616 #include "locking-selftest-spin.h"
617 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_spin)
619 #include "locking-selftest-wlock.h"
620 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_wlock)
622 #include "locking-selftest-rlock.h"
623 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)
625 #undef E1
626 #undef E2
629 * Enabling irqs with an irq-safe lock held:
631 #define E1() \
633 IRQ_ENTER(); \
634 LOCK(A); \
635 UNLOCK(A); \
636 IRQ_EXIT();
638 #define E2() \
640 IRQ_DISABLE(); \
641 LOCK(A); \
642 IRQ_ENABLE(); \
643 UNLOCK(A);
646 * Generate 24 testcases:
648 #include "locking-selftest-spin-hardirq.h"
649 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)
651 #include "locking-selftest-rlock-hardirq.h"
652 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)
654 #include "locking-selftest-wlock-hardirq.h"
655 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_wlock)
657 #include "locking-selftest-spin-softirq.h"
658 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_spin)
660 #include "locking-selftest-rlock-softirq.h"
661 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock)
663 #include "locking-selftest-wlock-softirq.h"
664 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)
666 #undef E1
667 #undef E2
670 * Acquiring a irq-unsafe lock while holding an irq-safe-lock:
672 #define E1() \
674 LOCK(A); \
675 LOCK(B); \
676 UNLOCK(B); \
677 UNLOCK(A); \
679 #define E2() \
681 LOCK(B); \
682 UNLOCK(B);
684 #define E3() \
686 IRQ_ENTER(); \
687 LOCK(A); \
688 UNLOCK(A); \
689 IRQ_EXIT();
692 * Generate 36 testcases:
694 #include "locking-selftest-spin-hardirq.h"
695 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)
697 #include "locking-selftest-rlock-hardirq.h"
698 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)
700 #include "locking-selftest-wlock-hardirq.h"
701 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_wlock)
703 #include "locking-selftest-spin-softirq.h"
704 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_spin)
706 #include "locking-selftest-rlock-softirq.h"
707 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock)
709 #include "locking-selftest-wlock-softirq.h"
710 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)
712 #undef E1
713 #undef E2
714 #undef E3
717 * If a lock turns into softirq-safe, but earlier it took
718 * a softirq-unsafe lock:
721 #define E1() \
722 IRQ_DISABLE(); \
723 LOCK(A); \
724 LOCK(B); \
725 UNLOCK(B); \
726 UNLOCK(A); \
727 IRQ_ENABLE();
729 #define E2() \
730 LOCK(B); \
731 UNLOCK(B);
733 #define E3() \
734 IRQ_ENTER(); \
735 LOCK(A); \
736 UNLOCK(A); \
737 IRQ_EXIT();
740 * Generate 36 testcases:
742 #include "locking-selftest-spin-hardirq.h"
743 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)
745 #include "locking-selftest-rlock-hardirq.h"
746 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)
748 #include "locking-selftest-wlock-hardirq.h"
749 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_wlock)
751 #include "locking-selftest-spin-softirq.h"
752 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_spin)
754 #include "locking-selftest-rlock-softirq.h"
755 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock)
757 #include "locking-selftest-wlock-softirq.h"
758 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)
760 #undef E1
761 #undef E2
762 #undef E3
765 * read-lock / write-lock irq inversion.
767 * Deadlock scenario:
769 * CPU#1 is at #1, i.e. it has write-locked A, but has not
770 * taken B yet.
772 * CPU#2 is at #2, i.e. it has locked B.
774 * Hardirq hits CPU#2 at point #2 and is trying to read-lock A.
776 * The deadlock occurs because CPU#1 will spin on B, and CPU#2
777 * will spin on A.
780 #define E1() \
782 IRQ_DISABLE(); \
783 WL(A); \
784 LOCK(B); \
785 UNLOCK(B); \
786 WU(A); \
787 IRQ_ENABLE();
789 #define E2() \
791 LOCK(B); \
792 UNLOCK(B);
794 #define E3() \
796 IRQ_ENTER(); \
797 RL(A); \
798 RU(A); \
799 IRQ_EXIT();
802 * Generate 36 testcases:
804 #include "locking-selftest-spin-hardirq.h"
805 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_spin)
807 #include "locking-selftest-rlock-hardirq.h"
808 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_rlock)
810 #include "locking-selftest-wlock-hardirq.h"
811 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_wlock)
813 #include "locking-selftest-spin-softirq.h"
814 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_spin)
816 #include "locking-selftest-rlock-softirq.h"
817 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_rlock)
819 #include "locking-selftest-wlock-softirq.h"
820 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_wlock)
822 #undef E1
823 #undef E2
824 #undef E3
827 * read-lock / write-lock recursion that is actually safe.
830 #define E1() \
832 IRQ_DISABLE(); \
833 WL(A); \
834 WU(A); \
835 IRQ_ENABLE();
837 #define E2() \
839 RL(A); \
840 RU(A); \
842 #define E3() \
844 IRQ_ENTER(); \
845 RL(A); \
846 L(B); \
847 U(B); \
848 RU(A); \
849 IRQ_EXIT();
852 * Generate 12 testcases:
854 #include "locking-selftest-hardirq.h"
855 GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_hard)
857 #include "locking-selftest-softirq.h"
858 GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
860 #undef E1
861 #undef E2
862 #undef E3
865 * read-lock / write-lock recursion that is unsafe.
868 #define E1() \
870 IRQ_DISABLE(); \
871 L(B); \
872 WL(A); \
873 WU(A); \
874 U(B); \
875 IRQ_ENABLE();
877 #define E2() \
879 RL(A); \
880 RU(A); \
882 #define E3() \
884 IRQ_ENTER(); \
885 L(B); \
886 U(B); \
887 IRQ_EXIT();
890 * Generate 12 testcases:
892 #include "locking-selftest-hardirq.h"
893 // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_hard)
895 #include "locking-selftest-softirq.h"
896 // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_soft)
898 #endif /* !CONFIG_PREEMPT_RT */
900 #ifdef CONFIG_DEBUG_LOCK_ALLOC
901 # define I_SPINLOCK(x) lockdep_reset_lock(&lock_##x.dep_map)
902 # define I_RWLOCK(x) lockdep_reset_lock(&rwlock_##x.dep_map)
903 # define I_MUTEX(x) lockdep_reset_lock(&mutex_##x.dep_map)
904 # define I_RWSEM(x) lockdep_reset_lock(&rwsem_##x.dep_map)
905 #else
906 # define I_SPINLOCK(x)
907 # define I_RWLOCK(x)
908 # define I_MUTEX(x)
909 # define I_RWSEM(x)
910 #endif
912 #define I1(x) \
913 do { \
914 I_SPINLOCK(x); \
915 I_RWLOCK(x); \
916 I_MUTEX(x); \
917 I_RWSEM(x); \
918 } while (0)
920 #define I2(x) \
921 do { \
922 spin_lock_init(&lock_##x); \
923 rwlock_init(&rwlock_##x); \
924 mutex_init(&mutex_##x); \
925 init_rwsem(&rwsem_##x); \
926 } while (0)
928 static void reset_locks(void)
930 local_irq_disable();
931 I1(A); I1(B); I1(C); I1(D);
932 I1(X1); I1(X2); I1(Y1); I1(Y2); I1(Z1); I1(Z2);
933 lockdep_reset();
934 I2(A); I2(B); I2(C); I2(D);
935 init_shared_classes();
936 local_irq_enable();
939 #undef I
941 static int testcase_total;
942 static int testcase_successes;
943 static int expected_testcase_failures;
944 static int unexpected_testcase_failures;
946 static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
948 unsigned long saved_preempt_count = preempt_count();
949 int expected_failure = 0;
950 #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_DEBUG_RT_MUTEXES)
951 long saved_lock_count = atomic_read(&current->lock_count);
952 #endif
954 WARN_ON(irqs_disabled());
956 testcase_fn();
958 * Filter out expected failures:
960 #ifndef CONFIG_PROVE_LOCKING
961 if ((lockclass_mask & LOCKTYPE_SPIN) && debug_locks != expected)
962 expected_failure = 1;
963 if ((lockclass_mask & LOCKTYPE_RWLOCK) && debug_locks != expected)
964 expected_failure = 1;
965 if ((lockclass_mask & LOCKTYPE_MUTEX) && debug_locks != expected)
966 expected_failure = 1;
967 if ((lockclass_mask & LOCKTYPE_RWSEM) && debug_locks != expected)
968 expected_failure = 1;
969 #endif
970 if (debug_locks != expected) {
971 if (expected_failure) {
972 expected_testcase_failures++;
973 printk("failed|");
974 } else {
975 unexpected_testcase_failures++;
977 printk("FAILED|");
978 dump_stack();
980 } else {
981 testcase_successes++;
982 printk(" ok |");
984 testcase_total++;
986 if (debug_locks_verbose)
987 printk(" lockclass mask: %x, debug_locks: %d, expected: %d\n",
988 lockclass_mask, debug_locks, expected);
990 * Some tests (e.g. double-unlock) might corrupt the preemption
991 * count, so restore it:
993 preempt_count() = saved_preempt_count;
994 #ifdef CONFIG_TRACE_IRQFLAGS
995 if (softirq_count())
996 current->softirqs_enabled = 0;
997 else
998 current->softirqs_enabled = 1;
999 #endif
1001 reset_locks();
1002 #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_DEBUG_RT_MUTEXES)
1003 atomic_set(&current->lock_count, saved_lock_count);
1004 #endif
1007 static inline void print_testname(const char *testname)
1009 printk("%33s:", testname);
1012 #define DO_TESTCASE_1(desc, name, nr) \
1013 print_testname(desc"/"#nr); \
1014 dotest(name##_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1015 printk("\n");
1017 #define DO_TESTCASE_1B(desc, name, nr) \
1018 print_testname(desc"/"#nr); \
1019 dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1020 printk("\n");
1022 #define DO_TESTCASE_3(desc, name, nr) \
1023 print_testname(desc"/"#nr); \
1024 dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN); \
1025 dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1026 dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1027 printk("\n");
1029 #define DO_TESTCASE_3RW(desc, name, nr) \
1030 print_testname(desc"/"#nr); \
1031 dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN|LOCKTYPE_RWLOCK);\
1032 dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \
1033 dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \
1034 printk("\n");
1036 #define DO_TESTCASE_6(desc, name) \
1037 print_testname(desc); \
1038 dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \
1039 dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \
1040 dotest(name##_rlock, FAILURE, LOCKTYPE_RWLOCK); \
1041 dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \
1042 dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \
1043 dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \
1044 printk("\n");
1046 #define DO_TESTCASE_6_SUCCESS(desc, name) \
1047 print_testname(desc); \
1048 dotest(name##_spin, SUCCESS, LOCKTYPE_SPIN); \
1049 dotest(name##_wlock, SUCCESS, LOCKTYPE_RWLOCK); \
1050 dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \
1051 dotest(name##_mutex, SUCCESS, LOCKTYPE_MUTEX); \
1052 dotest(name##_wsem, SUCCESS, LOCKTYPE_RWSEM); \
1053 dotest(name##_rsem, SUCCESS, LOCKTYPE_RWSEM); \
1054 printk("\n");
1057 * 'read' variant: rlocks must not trigger.
1059 #define DO_TESTCASE_6R(desc, name) \
1060 print_testname(desc); \
1061 dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \
1062 dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \
1063 dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \
1064 dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \
1065 dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \
1066 dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \
1067 printk("\n");
1069 #define DO_TESTCASE_2I(desc, name, nr) \
1070 DO_TESTCASE_1("hard-"desc, name##_hard, nr); \
1071 DO_TESTCASE_1("soft-"desc, name##_soft, nr);
1073 #define DO_TESTCASE_2IB(desc, name, nr) \
1074 DO_TESTCASE_1B("hard-"desc, name##_hard, nr); \
1075 DO_TESTCASE_1B("soft-"desc, name##_soft, nr);
1077 #define DO_TESTCASE_6I(desc, name, nr) \
1078 DO_TESTCASE_3("hard-"desc, name##_hard, nr); \
1079 DO_TESTCASE_3("soft-"desc, name##_soft, nr);
1081 #define DO_TESTCASE_6IRW(desc, name, nr) \
1082 DO_TESTCASE_3RW("hard-"desc, name##_hard, nr); \
1083 DO_TESTCASE_3RW("soft-"desc, name##_soft, nr);
1085 #define DO_TESTCASE_2x3(desc, name) \
1086 DO_TESTCASE_3(desc, name, 12); \
1087 DO_TESTCASE_3(desc, name, 21);
1089 #define DO_TESTCASE_2x6(desc, name) \
1090 DO_TESTCASE_6I(desc, name, 12); \
1091 DO_TESTCASE_6I(desc, name, 21);
1093 #define DO_TESTCASE_6x2(desc, name) \
1094 DO_TESTCASE_2I(desc, name, 123); \
1095 DO_TESTCASE_2I(desc, name, 132); \
1096 DO_TESTCASE_2I(desc, name, 213); \
1097 DO_TESTCASE_2I(desc, name, 231); \
1098 DO_TESTCASE_2I(desc, name, 312); \
1099 DO_TESTCASE_2I(desc, name, 321);
1101 #define DO_TESTCASE_6x2B(desc, name) \
1102 DO_TESTCASE_2IB(desc, name, 123); \
1103 DO_TESTCASE_2IB(desc, name, 132); \
1104 DO_TESTCASE_2IB(desc, name, 213); \
1105 DO_TESTCASE_2IB(desc, name, 231); \
1106 DO_TESTCASE_2IB(desc, name, 312); \
1107 DO_TESTCASE_2IB(desc, name, 321);
1109 #define DO_TESTCASE_6x6(desc, name) \
1110 DO_TESTCASE_6I(desc, name, 123); \
1111 DO_TESTCASE_6I(desc, name, 132); \
1112 DO_TESTCASE_6I(desc, name, 213); \
1113 DO_TESTCASE_6I(desc, name, 231); \
1114 DO_TESTCASE_6I(desc, name, 312); \
1115 DO_TESTCASE_6I(desc, name, 321);
1117 #define DO_TESTCASE_6x6RW(desc, name) \
1118 DO_TESTCASE_6IRW(desc, name, 123); \
1119 DO_TESTCASE_6IRW(desc, name, 132); \
1120 DO_TESTCASE_6IRW(desc, name, 213); \
1121 DO_TESTCASE_6IRW(desc, name, 231); \
1122 DO_TESTCASE_6IRW(desc, name, 312); \
1123 DO_TESTCASE_6IRW(desc, name, 321);
1126 void locking_selftest(void)
1129 * Got a locking failure before the selftest ran?
1131 if (!debug_locks) {
1132 printk("----------------------------------\n");
1133 printk("| Locking API testsuite disabled |\n");
1134 printk("----------------------------------\n");
1135 return;
1139 * Run the testsuite:
1141 printk("------------------------\n");
1142 printk("| Locking API testsuite:\n");
1143 printk("----------------------------------------------------------------------------\n");
1144 printk(" | spin |wlock |rlock |mutex | wsem | rsem |\n");
1145 printk(" --------------------------------------------------------------------------\n");
1147 init_shared_classes();
1148 debug_locks_silent = !debug_locks_verbose;
1150 DO_TESTCASE_6R("A-A deadlock", AA);
1151 DO_TESTCASE_6R("A-B-B-A deadlock", ABBA);
1152 DO_TESTCASE_6R("A-B-B-C-C-A deadlock", ABBCCA);
1153 DO_TESTCASE_6R("A-B-C-A-B-C deadlock", ABCABC);
1154 DO_TESTCASE_6R("A-B-B-C-C-D-D-A deadlock", ABBCCDDA);
1155 DO_TESTCASE_6R("A-B-C-D-B-D-D-A deadlock", ABCDBDDA);
1156 DO_TESTCASE_6R("A-B-C-D-B-C-D-A deadlock", ABCDBCDA);
1157 DO_TESTCASE_6("double unlock", double_unlock);
1158 DO_TESTCASE_6("initialize held", init_held);
1159 DO_TESTCASE_6_SUCCESS("bad unlock order", bad_unlock_order);
1161 printk(" --------------------------------------------------------------------------\n");
1162 print_testname("recursive read-lock");
1163 printk(" |");
1164 dotest(rlock_AA1, SUCCESS, LOCKTYPE_RWLOCK);
1165 printk(" |");
1166 dotest(rsem_AA1, FAILURE, LOCKTYPE_RWSEM);
1167 printk("\n");
1169 print_testname("recursive read-lock #2");
1170 printk(" |");
1171 dotest(rlock_AA1B, SUCCESS, LOCKTYPE_RWLOCK);
1172 printk(" |");
1173 dotest(rsem_AA1B, FAILURE, LOCKTYPE_RWSEM);
1174 printk("\n");
1176 print_testname("mixed read-write-lock");
1177 printk(" |");
1178 dotest(rlock_AA2, FAILURE, LOCKTYPE_RWLOCK);
1179 printk(" |");
1180 dotest(rsem_AA2, FAILURE, LOCKTYPE_RWSEM);
1181 printk("\n");
1183 print_testname("mixed write-read-lock");
1184 printk(" |");
1185 dotest(rlock_AA3, FAILURE, LOCKTYPE_RWLOCK);
1186 printk(" |");
1187 dotest(rsem_AA3, FAILURE, LOCKTYPE_RWSEM);
1188 printk("\n");
1190 printk(" --------------------------------------------------------------------------\n");
1193 * irq-context testcases:
1195 #ifndef CONFIG_PREEMPT_RT
1196 DO_TESTCASE_2x6("irqs-on + irq-safe-A", irqsafe1);
1197 DO_TESTCASE_2x3("sirq-safe-A => hirqs-on", irqsafe2A);
1198 DO_TESTCASE_2x6("safe-A + irqs-on", irqsafe2B);
1199 DO_TESTCASE_6x6("safe-A + unsafe-B #1", irqsafe3);
1200 DO_TESTCASE_6x6("safe-A + unsafe-B #2", irqsafe4);
1201 DO_TESTCASE_6x6RW("irq lock-inversion", irq_inversion);
1203 DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
1204 // DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);
1205 #endif
1207 if (unexpected_testcase_failures) {
1208 printk("-----------------------------------------------------------------\n");
1209 debug_locks = 0;
1210 printk("BUG: %3d unexpected failures (out of %3d) - debugging disabled! |\n",
1211 unexpected_testcase_failures, testcase_total);
1212 printk("-----------------------------------------------------------------\n");
1213 } else if (expected_testcase_failures && testcase_successes) {
1214 printk("--------------------------------------------------------\n");
1215 printk("%3d out of %3d testcases failed, as expected. |\n",
1216 expected_testcase_failures, testcase_total);
1217 printk("----------------------------------------------------\n");
1218 debug_locks = 1;
1219 } else if (expected_testcase_failures && !testcase_successes) {
1220 printk("--------------------------------------------------------\n");
1221 printk("All %3d testcases failed, as expected. |\n",
1222 expected_testcase_failures);
1223 printk("----------------------------------------\n");
1224 debug_locks = 1;
1225 } else {
1226 printk("-------------------------------------------------------\n");
1227 printk("Good, all %3d testcases passed! |\n",
1228 testcase_successes);
1229 printk("---------------------------------\n");
1230 debug_locks = 1;
1232 debug_locks_silent = 0;