1 /* SPDX-License-Identifier: GPL-2.0 */ 1
2 /*
3 * Runtime locking correctness validator
4 *
5 * Copyright (C) 2006,2007 Red Hat, Inc., Ing
6 * Copyright (C) 2007 Red Hat, Inc., Peter Zi
7 *
8 * see Documentation/locking/lockdep-design.rs
9 */
10 #ifndef __LINUX_LOCKDEP_H
11 #define __LINUX_LOCKDEP_H
12
13 #include <linux/lockdep_types.h>
14 #include <linux/smp.h>
15 #include <asm/percpu.h>
16
17 struct task_struct;
18
19 #ifdef CONFIG_LOCKDEP
20
21 #include <linux/linkage.h>
22 #include <linux/list.h>
23 #include <linux/debug_locks.h>
24 #include <linux/stacktrace.h>
25
26 static inline void lockdep_copy_map(struct loc
27 struct loc
28 {
29 int i;
30
31 *to = *from;
32 /*
33 * Since the class cache can be modifi
34 * half pointers (64bit arch using 32b
35 * the caches and take the performance
36 *
37 * XXX it doesn't work well with lockd
38 * that relies on cache abuse.
39 */
40 for (i = 0; i < NR_LOCKDEP_CACHING_CLA
41 to->class_cache[i] = NULL;
42 }
43
44 /*
45 * Every lock has a list of other locks that w
46 * We only grow the list, never remove from it
47 */
48 struct lock_list {
49 struct list_head entry;
50 struct lock_class *class
51 struct lock_class *links
52 const struct lock_trace *trace
53 u16 distan
54 /* bitmap of different dependencies fr
55 u8 dep;
56 /* used by BFS to record whether "prev
57 u8 only_x
58
59 /*
60 * The parent field is used to impleme
61 * bit 0 is reused to indicate if the
62 */
63 struct lock_list *paren
64 };
65
66 /**
67 * struct lock_chain - lock dependency chain r
68 *
69 * @irq_context: the same as irq_context in he
70 * @depth: the number of held locks in t
71 * @base: the index in chain_hlocks for
72 * @entry: the collided lock chains in l
73 * @chain_key: the hash key of this lock_cha
74 */
75 struct lock_chain {
76 /* see BUILD_BUG_ON()s in add_chain_ca
77 unsigned int irq_co
78 depth
79 base
80 /* 4 byte hole */
81 struct hlist_node entry;
82 u64 chain_
83 };
84
85 /*
86 * Initialization, self-test and debugging-out
87 */
88 extern void lockdep_init(void);
89 extern void lockdep_reset(void);
90 extern void lockdep_reset_lock(struct lockdep_
91 extern void lockdep_free_key_range(void *start
92 extern asmlinkage void lockdep_sys_exit(void);
93 extern void lockdep_set_selftest_task(struct t
94
95 extern void lockdep_init_task(struct task_stru
96
97 /*
98 * Split the recursion counter in two to readi
99 */
100 #define LOCKDEP_RECURSION_BITS 16
101 #define LOCKDEP_OFF (1U << LOCKDEP
102 #define LOCKDEP_RECURSION_MASK (LOCKDEP_OFF -
103
104 /*
105 * lockdep_{off,on}() are macros to avoid trac
106 * to header dependencies.
107 */
108
109 #define lockdep_off()
110 do {
111 current->lockdep_recursion += LOCKDEP_
112 } while (0)
113
114 #define lockdep_on()
115 do {
116 current->lockdep_recursion -= LOCKDEP_
117 } while (0)
118
119 extern void lockdep_register_key(struct lock_c
120 extern void lockdep_unregister_key(struct lock
121
122 /*
123 * These methods are used by specific locking
124 * rwlocks, mutexes and rwsems) to pass init/a
125 * to lockdep:
126 */
127
128 extern void lockdep_init_map_type(struct lockd
129 struct lock_class_key *key, int subcla
130
131 static inline void
132 lockdep_init_map_waits(struct lockdep_map *loc
133 struct lock_class_key *
134 {
135 lockdep_init_map_type(lock, name, key,
136 }
137
138 static inline void
139 lockdep_init_map_wait(struct lockdep_map *lock
140 struct lock_class_key *k
141 {
142 lockdep_init_map_waits(lock, name, key
143 }
144
145 static inline void lockdep_init_map(struct loc
146 struct lock_class
147 {
148 lockdep_init_map_wait(lock, name, key,
149 }
150
151 /*
152 * Reinitialize a lock key - for cases where t
153 * special initialization of locks so that the
154 * of dependencies wrong: they are either too
155 * or they are too narrow (they suffer from a
156 */
157 #define lockdep_set_class(lock, key)
158 lockdep_init_map_type(&(lock)->dep_map
159 (lock)->dep_map.
160 (lock)->dep_map.
161 (lock)->dep_map.
162
163 #define lockdep_set_class_and_name(lock, key,
164 lockdep_init_map_type(&(lock)->dep_map
165 (lock)->dep_map.
166 (lock)->dep_map.
167 (lock)->dep_map.
168
169 #define lockdep_set_class_and_subclass(lock, k
170 lockdep_init_map_type(&(lock)->dep_map
171 (lock)->dep_map.
172 (lock)->dep_map.
173 (lock)->dep_map.
174
175 #define lockdep_set_subclass(lock, sub)
176 lockdep_init_map_type(&(lock)->dep_map
177 (lock)->dep_map.
178 (lock)->dep_map.
179 (lock)->dep_map.
180
181 /**
182 * lockdep_set_novalidate_class: disable check
183 * lock
184 * @lock: Lock to mark
185 *
186 * Lockdep will still record that this lock ha
187 * instances when dumping locks
188 */
189 #define lockdep_set_novalidate_class(lock) \
190 lockdep_set_class_and_name(lock, &__lo
191
192 /**
193 * lockdep_set_notrack_class: disable lockdep
194 * @lock: Lock to mark
195 *
196 * Bigger hammer than lockdep_set_novalidate_c
197 * which takes more locks than lockdep is able
198 */
199 #define lockdep_set_notrack_class(lock) \
200 lockdep_set_class_and_name(lock, &__lo
201
202 /*
203 * Compare locking classes
204 */
205 #define lockdep_match_class(lock, key) lockdep
206
207 static inline int lockdep_match_key(struct loc
208 struct loc
209 {
210 return lock->key == key;
211 }
212
213 /*
214 * Acquire a lock.
215 *
216 * Values for "read":
217 *
218 * 0: exclusive (write) acquire
219 * 1: read-acquire (no recursion allowed)
220 * 2: read-acquire with same-instance recurs
221 *
222 * Values for check:
223 *
224 * 0: simple checks (freeing, held-at-exit-t
225 * 1: full validation
226 */
227 extern void lock_acquire(struct lockdep_map *l
228 int trylock, int read
229 struct lockdep_map *n
230
231 extern void lock_release(struct lockdep_map *l
232
233 extern void lock_sync(struct lockdep_map *lock
234 int read, int check, str
235 unsigned long ip);
236
237 /* lock_is_held_type() returns */
238 #define LOCK_STATE_UNKNOWN -1
239 #define LOCK_STATE_NOT_HELD 0
240 #define LOCK_STATE_HELD 1
241
242 /*
243 * Same "read" as for lock_acquire(), except -
244 */
245 extern int lock_is_held_type(const struct lock
246
247 static inline int lock_is_held(const struct lo
248 {
249 return lock_is_held_type(lock, -1);
250 }
251
252 #define lockdep_is_held(lock) lock_i
253 #define lockdep_is_held_type(lock, r) lock_i
254
255 extern void lock_set_class(struct lockdep_map
256 struct lock_class_k
257 unsigned long ip);
258
259 #define lock_set_novalidate_class(l, n, i) \
260 lock_set_class(l, n, &__lockdep_no_val
261
262 static inline void lock_set_subclass(struct lo
263 unsigned int subclass, unsigne
264 {
265 lock_set_class(lock, lock->name, lock-
266 }
267
268 extern void lock_downgrade(struct lockdep_map
269
270 #define NIL_COOKIE (struct pin_cookie){ .val =
271
272 extern struct pin_cookie lock_pin_lock(struct
273 extern void lock_repin_lock(struct lockdep_map
274 extern void lock_unpin_lock(struct lockdep_map
275
276 #define lockdep_depth(tsk) (debug_locks ?
277
278 #define lockdep_assert(cond) \
279 do { WARN_ON(debug_locks && !(cond));
280
281 #define lockdep_assert_once(cond) \
282 do { WARN_ON_ONCE(debug_locks && !(con
283
284 #define lockdep_assert_held(l) \
285 lockdep_assert(lockdep_is_held(l) != L
286
287 #define lockdep_assert_not_held(l) \
288 lockdep_assert(lockdep_is_held(l) != L
289
290 #define lockdep_assert_held_write(l) \
291 lockdep_assert(lockdep_is_held_type(l,
292
293 #define lockdep_assert_held_read(l) \
294 lockdep_assert(lockdep_is_held_type(l,
295
296 #define lockdep_assert_held_once(l)
297 lockdep_assert_once(lockdep_is_held(l)
298
299 #define lockdep_assert_none_held_once()
300 lockdep_assert_once(!current->lockdep_
301
302 #define lockdep_recursing(tsk) ((tsk)->lockde
303
304 #define lockdep_pin_lock(l) lock_pin_lock(
305 #define lockdep_repin_lock(l,c) lock_repin_loc
306 #define lockdep_unpin_lock(l,c) lock_unpin_loc
307
308 /*
309 * Must use lock_map_aquire_try() with overrid
310 * lockdep thinking they participate in the bl
311 */
312 #define DEFINE_WAIT_OVERRIDE_MAP(_name, _wait_
313 struct lockdep_map _name = {
314 .name = #_name "-wait-type-ove
315 .wait_type_inner = _wait_type,
316 .lock_type = LD_LOCK_WAIT_OVER
317
318 #else /* !CONFIG_LOCKDEP */
319
320 static inline void lockdep_init_task(struct ta
321 {
322 }
323
324 static inline void lockdep_off(void)
325 {
326 }
327
328 static inline void lockdep_on(void)
329 {
330 }
331
332 static inline void lockdep_set_selftest_task(s
333 {
334 }
335
336 # define lock_acquire(l, s, t, r, c, n, i)
337 # define lock_release(l, i)
338 # define lock_downgrade(l, i)
339 # define lock_set_class(l, n, key, s, i)
340 # define lock_set_novalidate_class(l, n, i)
341 # define lock_set_subclass(l, s, i)
342 # define lockdep_init()
343 # define lockdep_init_map_type(lock, name, key
344 do { (void)(name); (void)(key)
345 # define lockdep_init_map_waits(lock, name, ke
346 do { (void)(name); (void)(key)
347 # define lockdep_init_map_wait(lock, name, key
348 do { (void)(name); (void)(key)
349 # define lockdep_init_map(lock, name, key, sub
350 do { (void)(name); (void)(key)
351 # define lockdep_set_class(lock, key)
352 # define lockdep_set_class_and_name(lock, key,
353 do { (void)(key); (void)(name)
354 #define lockdep_set_class_and_subclass(lock, k
355 do { (void)(key); } while (0)
356 #define lockdep_set_subclass(lock, sub)
357
358 #define lockdep_set_novalidate_class(lock) do
359 #define lockdep_set_notrack_class(lock) do { }
360
361 /*
362 * We don't define lockdep_match_class() and l
363 * case since the result is not well defined a
364 * #ifdef the call himself.
365 */
366
367 # define lockdep_reset() do { d
368 # define lockdep_free_key_range(start, size)
369 # define lockdep_sys_exit()
370
371 static inline void lockdep_register_key(struct
372 {
373 }
374
375 static inline void lockdep_unregister_key(stru
376 {
377 }
378
379 #define lockdep_depth(tsk) (0)
380
381 /*
382 * Dummy forward declarations, allow users to
383 * and depend on dead code elimination.
384 */
385 extern int lock_is_held(const void *);
386 extern int lockdep_is_held(const void *);
387 #define lockdep_is_held_type(l, r)
388
389 #define lockdep_assert(c)
390 #define lockdep_assert_once(c)
391
392 #define lockdep_assert_held(l)
393 #define lockdep_assert_not_held(l)
394 #define lockdep_assert_held_write(l)
395 #define lockdep_assert_held_read(l)
396 #define lockdep_assert_held_once(l)
397 #define lockdep_assert_none_held_once() do { }
398
399 #define lockdep_recursing(tsk)
400
401 #define NIL_COOKIE (struct pin_cookie){ }
402
403 #define lockdep_pin_lock(l)
404 #define lockdep_repin_lock(l, c)
405 #define lockdep_unpin_lock(l, c)
406
407 #define DEFINE_WAIT_OVERRIDE_MAP(_name, _wait_
408 struct lockdep_map __maybe_unused _nam
409
410 #endif /* !LOCKDEP */
411
412 #ifdef CONFIG_PROVE_LOCKING
413 void lockdep_set_lock_cmp_fn(struct lockdep_ma
414
415 #define lock_set_cmp_fn(lock, ...) lockde
416 #else
417 #define lock_set_cmp_fn(lock, ...) do { }
418 #endif
419
420 enum xhlock_context_t {
421 XHLOCK_HARD,
422 XHLOCK_SOFT,
423 XHLOCK_CTX_NR,
424 };
425
426 /*
427 * To initialize a lockdep_map statically use
428 * Note that _name must not be NULL.
429 */
430 #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \
431 { .name = (_name), .key = (void *)(_ke
432
433 static inline void lockdep_invariant_state(boo
434 static inline void lockdep_free_task(struct ta
435
436 #ifdef CONFIG_LOCK_STAT
437
438 extern void lock_contended(struct lockdep_map
439 extern void lock_acquired(struct lockdep_map *
440
441 #define LOCK_CONTENDED(_lock, try, lock)
442 do {
443 if (!try(_lock)) {
444 lock_contended(&(_lock)->dep_m
445 lock(_lock);
446 }
447 lock_acquired(&(_lock)->dep_map, _RET_
448 } while (0)
449
450 #define LOCK_CONTENDED_RETURN(_lock, try, lock
451 ({
452 int ____err = 0;
453 if (!try(_lock)) {
454 lock_contended(&(_lock)->dep_m
455 ____err = lock(_lock);
456 }
457 if (!____err)
458 lock_acquired(&(_lock)->dep_ma
459 ____err;
460 })
461
462 #else /* CONFIG_LOCK_STAT */
463
464 #define lock_contended(lockdep_map, ip) do {}
465 #define lock_acquired(lockdep_map, ip) do {} w
466
467 #define LOCK_CONTENDED(_lock, try, lock) \
468 lock(_lock)
469
470 #define LOCK_CONTENDED_RETURN(_lock, try, lock
471 lock(_lock)
472
473 #endif /* CONFIG_LOCK_STAT */
474
475 #ifdef CONFIG_PROVE_LOCKING
476 extern void print_irqtrace_events(struct task_
477 #else
478 static inline void print_irqtrace_events(struc
479 {
480 }
481 #endif
482
483 /* Variable used to make lockdep treat read_lo
484 #ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS
485 extern unsigned int force_read_lock_recursive;
486 #else /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
487 #define force_read_lock_recursive 0
488 #endif /* CONFIG_DEBUG_LOCKING_API_SELFTESTS *
489
490 #ifdef CONFIG_LOCKDEP
491 extern bool read_lock_is_recursive(void);
492 #else /* CONFIG_LOCKDEP */
493 /* If !LOCKDEP, the value is meaningless */
494 #define read_lock_is_recursive() 0
495 #endif
496
497 /*
498 * For trivial one-depth nesting of a lock-cla
499 * global define can be used. (Subsystems with
500 * of nesting should define their own lock-nes
501 */
502 #define SINGLE_DEPTH_NESTING
503
504 /*
505 * Map the dependency ops to NOP or to real lo
506 * on the per lock-class debug mode:
507 */
508
509 #define lock_acquire_exclusive(l, s, t, n, i)
510 #define lock_acquire_shared(l, s, t, n, i)
511 #define lock_acquire_shared_recursive(l, s, t,
512
513 #define spin_acquire(l, s, t, i)
514 #define spin_acquire_nest(l, s, t, n, i)
515 #define spin_release(l, i)
516
517 #define rwlock_acquire(l, s, t, i)
518 #define rwlock_acquire_read(l, s, t, i)
519 do {
520 if (read_lock_is_recursive())
521 lock_acquire_shared_recursive(
522 else
523 lock_acquire_shared(l, s, t, N
524 } while (0)
525
526 #define rwlock_release(l, i)
527
528 #define seqcount_acquire(l, s, t, i)
529 #define seqcount_acquire_read(l, s, t, i)
530 #define seqcount_release(l, i)
531
532 #define mutex_acquire(l, s, t, i)
533 #define mutex_acquire_nest(l, s, t, n, i)
534 #define mutex_release(l, i)
535
536 #define rwsem_acquire(l, s, t, i)
537 #define rwsem_acquire_nest(l, s, t, n, i)
538 #define rwsem_acquire_read(l, s, t, i)
539 #define rwsem_release(l, i)
540
541 #define lock_map_acquire(l)
542 #define lock_map_acquire_try(l)
543 #define lock_map_acquire_read(l)
544 #define lock_map_acquire_tryread(l)
545 #define lock_map_release(l)
546 #define lock_map_sync(l)
547
548 #ifdef CONFIG_PROVE_LOCKING
549 # define might_lock(lock)
550 do {
551 typecheck(struct lockdep_map *, &(lock
552 lock_acquire(&(lock)->dep_map, 0, 0, 0
553 lock_release(&(lock)->dep_map, _THIS_I
554 } while (0)
555 # define might_lock_read(lock)
556 do {
557 typecheck(struct lockdep_map *, &(lock
558 lock_acquire(&(lock)->dep_map, 0, 0, 1
559 lock_release(&(lock)->dep_map, _THIS_I
560 } while (0)
561 # define might_lock_nested(lock, subclass)
562 do {
563 typecheck(struct lockdep_map *, &(lock
564 lock_acquire(&(lock)->dep_map, subclas
565 _THIS_IP_);
566 lock_release(&(lock)->dep_map, _THIS_I
567 } while (0)
568
569 DECLARE_PER_CPU(int, hardirqs_enabled);
570 DECLARE_PER_CPU(int, hardirq_context);
571 DECLARE_PER_CPU(unsigned int, lockdep_recursio
572
573 #define __lockdep_enabled (debug_locks &
574
575 #define lockdep_assert_irqs_enabled()
576 do {
577 WARN_ON_ONCE(__lockdep_enabled && !thi
578 } while (0)
579
580 #define lockdep_assert_irqs_disabled()
581 do {
582 WARN_ON_ONCE(__lockdep_enabled && this
583 } while (0)
584
585 #define lockdep_assert_in_irq()
586 do {
587 WARN_ON_ONCE(__lockdep_enabled && !thi
588 } while (0)
589
590 #define lockdep_assert_no_hardirq()
591 do {
592 WARN_ON_ONCE(__lockdep_enabled && (thi
593 !th
594 } while (0)
595
596 #define lockdep_assert_preemption_enabled()
597 do {
598 WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT
599 __lockdep_enabled
600 (preempt_count() != 0
601 !this_cpu_read(hardirqs_
602 } while (0)
603
604 #define lockdep_assert_preemption_disabled()
605 do {
606 WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT
607 __lockdep_enabled
608 (preempt_count() == 0
609 this_cpu_read(hardirqs_e
610 } while (0)
611
612 /*
613 * Acceptable for protecting per-CPU resources
614 * Much like in_softirq() - semantics are ambi
615 */
616 #define lockdep_assert_in_softirq()
617 do {
618 WARN_ON_ONCE(__lockdep_enabled
619 (!in_softirq() || in_irq(
620 } while (0)
621
622 extern void lockdep_assert_in_softirq_func(voi
623
624 #else
625 # define might_lock(lock) do { } while (0)
626 # define might_lock_read(lock) do { } while (0
627 # define might_lock_nested(lock, subclass) do
628
629 # define lockdep_assert_irqs_enabled() do { }
630 # define lockdep_assert_irqs_disabled() do { }
631 # define lockdep_assert_in_irq() do { } while
632 # define lockdep_assert_no_hardirq() do { } wh
633
634 # define lockdep_assert_preemption_enabled() d
635 # define lockdep_assert_preemption_disabled()
636 # define lockdep_assert_in_softirq() do { } wh
637 # define lockdep_assert_in_softirq_func() do {
638 #endif
639
640 #ifdef CONFIG_PROVE_RAW_LOCK_NESTING
641
642 # define lockdep_assert_RT_in_threaded_ctx() d
643 WARN_ONCE(debug_locks && !curr
644 lockdep_hardirq_cont
645 !(current->hardirq_t
646 "Not in threaded con
647 } while (0)
648
649 #else
650
651 # define lockdep_assert_RT_in_threaded_ctx() d
652
653 #endif
654
655 #ifdef CONFIG_LOCKDEP
656 void lockdep_rcu_suspicious(const char *file,
657 #else
658 static inline void
659 lockdep_rcu_suspicious(const char *file, const
660 {
661 }
662 #endif
663
664 #endif /* __LINUX_LOCKDEP_H */
665
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