1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Runtime locking correctness validator
4 *
5 * Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
6 * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
7 *
8 * see Documentation/locking/lockdep-design.rst for more details.
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
lockdep_copy_map(struct lockdep_map * to,struct lockdep_map * from)26 static inline void lockdep_copy_map(struct lockdep_map *to,
27 struct lockdep_map *from)
28 {
29 int i;
30
31 *to = *from;
32 /*
33 * Since the class cache can be modified concurrently we could observe
34 * half pointers (64bit arch using 32bit copy insns). Therefore clear
35 * the caches and take the performance hit.
36 *
37 * XXX it doesn't work well with lockdep_set_class_and_subclass(), since
38 * that relies on cache abuse.
39 */
40 for (i = 0; i < NR_LOCKDEP_CACHING_CLASSES; i++)
41 to->class_cache[i] = NULL;
42 }
43
44 /*
45 * Every lock has a list of other locks that were taken after it.
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_to;
52 const struct lock_trace *trace;
53 u16 distance;
54 /* bitmap of different dependencies from head to this */
55 u8 dep;
56 /* used by BFS to record whether "prev -> this" only has -(*R)-> */
57 u8 only_xr;
58
59 /*
60 * The parent field is used to implement breadth-first search, and the
61 * bit 0 is reused to indicate if the lock has been accessed in BFS.
62 */
63 struct lock_list *parent;
64 };
65
66 /**
67 * struct lock_chain - lock dependency chain record
68 *
69 * @irq_context: the same as irq_context in held_lock below
70 * @depth: the number of held locks in this chain
71 * @base: the index in chain_hlocks for this chain
72 * @entry: the collided lock chains in lock_chain hash list
73 * @chain_key: the hash key of this lock_chain
74 */
75 struct lock_chain {
76 /* see BUILD_BUG_ON()s in add_chain_cache() */
77 unsigned int irq_context : 2,
78 depth : 6,
79 base : 24;
80 /* 4 byte hole */
81 struct hlist_node entry;
82 u64 chain_key;
83 };
84
85 #define MAX_LOCKDEP_KEYS_BITS 13
86 #define MAX_LOCKDEP_KEYS (1UL << MAX_LOCKDEP_KEYS_BITS)
87 #define INITIAL_CHAIN_KEY -1
88
89 struct held_lock {
90 /*
91 * One-way hash of the dependency chain up to this point. We
92 * hash the hashes step by step as the dependency chain grows.
93 *
94 * We use it for dependency-caching and we skip detection
95 * passes and dependency-updates if there is a cache-hit, so
96 * it is absolutely critical for 100% coverage of the validator
97 * to have a unique key value for every unique dependency path
98 * that can occur in the system, to make a unique hash value
99 * as likely as possible - hence the 64-bit width.
100 *
101 * The task struct holds the current hash value (initialized
102 * with zero), here we store the previous hash value:
103 */
104 u64 prev_chain_key;
105 unsigned long acquire_ip;
106 struct lockdep_map *instance;
107 struct lockdep_map *nest_lock;
108 #ifdef CONFIG_LOCK_STAT
109 u64 waittime_stamp;
110 u64 holdtime_stamp;
111 #endif
112 /*
113 * class_idx is zero-indexed; it points to the element in
114 * lock_classes this held lock instance belongs to. class_idx is in
115 * the range from 0 to (MAX_LOCKDEP_KEYS-1) inclusive.
116 */
117 unsigned int class_idx:MAX_LOCKDEP_KEYS_BITS;
118 /*
119 * The lock-stack is unified in that the lock chains of interrupt
120 * contexts nest ontop of process context chains, but we 'separate'
121 * the hashes by starting with 0 if we cross into an interrupt
122 * context, and we also keep do not add cross-context lock
123 * dependencies - the lock usage graph walking covers that area
124 * anyway, and we'd just unnecessarily increase the number of
125 * dependencies otherwise. [Note: hardirq and softirq contexts
126 * are separated from each other too.]
127 *
128 * The following field is used to detect when we cross into an
129 * interrupt context:
130 */
131 unsigned int irq_context:2; /* bit 0 - soft, bit 1 - hard */
132 unsigned int trylock:1; /* 16 bits */
133
134 unsigned int read:2; /* see lock_acquire() comment */
135 unsigned int check:1; /* see lock_acquire() comment */
136 unsigned int hardirqs_off:1;
137 unsigned int references:12; /* 32 bits */
138 unsigned int pin_count;
139 };
140
141 /*
142 * Initialization, self-test and debugging-output methods:
143 */
144 extern void lockdep_init(void);
145 extern void lockdep_reset(void);
146 extern void lockdep_reset_lock(struct lockdep_map *lock);
147 extern void lockdep_free_key_range(void *start, unsigned long size);
148 extern asmlinkage void lockdep_sys_exit(void);
149 extern void lockdep_set_selftest_task(struct task_struct *task);
150
151 extern void lockdep_init_task(struct task_struct *task);
152
153 /*
154 * Split the recursion counter in two to readily detect 'off' vs recursion.
155 */
156 #define LOCKDEP_RECURSION_BITS 16
157 #define LOCKDEP_OFF (1U << LOCKDEP_RECURSION_BITS)
158 #define LOCKDEP_RECURSION_MASK (LOCKDEP_OFF - 1)
159
160 /*
161 * lockdep_{off,on}() are macros to avoid tracing and kprobes; not inlines due
162 * to header dependencies.
163 */
164
165 #define lockdep_off() \
166 do { \
167 current->lockdep_recursion += LOCKDEP_OFF; \
168 } while (0)
169
170 #define lockdep_on() \
171 do { \
172 current->lockdep_recursion -= LOCKDEP_OFF; \
173 } while (0)
174
175 extern void lockdep_register_key(struct lock_class_key *key);
176 extern void lockdep_unregister_key(struct lock_class_key *key);
177
178 /*
179 * These methods are used by specific locking variants (spinlocks,
180 * rwlocks, mutexes and rwsems) to pass init/acquire/release events
181 * to lockdep:
182 */
183
184 extern void lockdep_init_map_type(struct lockdep_map *lock, const char *name,
185 struct lock_class_key *key, int subclass, u8 inner, u8 outer, u8 lock_type);
186
187 static inline void
lockdep_init_map_waits(struct lockdep_map * lock,const char * name,struct lock_class_key * key,int subclass,u8 inner,u8 outer)188 lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
189 struct lock_class_key *key, int subclass, u8 inner, u8 outer)
190 {
191 lockdep_init_map_type(lock, name, key, subclass, inner, outer, LD_LOCK_NORMAL);
192 }
193
194 static inline void
lockdep_init_map_wait(struct lockdep_map * lock,const char * name,struct lock_class_key * key,int subclass,u8 inner)195 lockdep_init_map_wait(struct lockdep_map *lock, const char *name,
196 struct lock_class_key *key, int subclass, u8 inner)
197 {
198 lockdep_init_map_waits(lock, name, key, subclass, inner, LD_WAIT_INV);
199 }
200
lockdep_init_map(struct lockdep_map * lock,const char * name,struct lock_class_key * key,int subclass)201 static inline void lockdep_init_map(struct lockdep_map *lock, const char *name,
202 struct lock_class_key *key, int subclass)
203 {
204 lockdep_init_map_wait(lock, name, key, subclass, LD_WAIT_INV);
205 }
206
207 /*
208 * Reinitialize a lock key - for cases where there is special locking or
209 * special initialization of locks so that the validator gets the scope
210 * of dependencies wrong: they are either too broad (they need a class-split)
211 * or they are too narrow (they suffer from a false class-split):
212 */
213 #define lockdep_set_class(lock, key) \
214 lockdep_init_map_type(&(lock)->dep_map, #key, key, 0, \
215 (lock)->dep_map.wait_type_inner, \
216 (lock)->dep_map.wait_type_outer, \
217 (lock)->dep_map.lock_type)
218
219 #define lockdep_set_class_and_name(lock, key, name) \
220 lockdep_init_map_type(&(lock)->dep_map, name, key, 0, \
221 (lock)->dep_map.wait_type_inner, \
222 (lock)->dep_map.wait_type_outer, \
223 (lock)->dep_map.lock_type)
224
225 #define lockdep_set_class_and_subclass(lock, key, sub) \
226 lockdep_init_map_type(&(lock)->dep_map, #key, key, sub, \
227 (lock)->dep_map.wait_type_inner, \
228 (lock)->dep_map.wait_type_outer, \
229 (lock)->dep_map.lock_type)
230
231 #define lockdep_set_subclass(lock, sub) \
232 lockdep_init_map_type(&(lock)->dep_map, #lock, (lock)->dep_map.key, sub,\
233 (lock)->dep_map.wait_type_inner, \
234 (lock)->dep_map.wait_type_outer, \
235 (lock)->dep_map.lock_type)
236
237 #define lockdep_set_novalidate_class(lock) \
238 lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock)
239
240 /*
241 * Compare locking classes
242 */
243 #define lockdep_match_class(lock, key) lockdep_match_key(&(lock)->dep_map, key)
244
lockdep_match_key(struct lockdep_map * lock,struct lock_class_key * key)245 static inline int lockdep_match_key(struct lockdep_map *lock,
246 struct lock_class_key *key)
247 {
248 return lock->key == key;
249 }
250
251 /*
252 * Acquire a lock.
253 *
254 * Values for "read":
255 *
256 * 0: exclusive (write) acquire
257 * 1: read-acquire (no recursion allowed)
258 * 2: read-acquire with same-instance recursion allowed
259 *
260 * Values for check:
261 *
262 * 0: simple checks (freeing, held-at-exit-time, etc.)
263 * 1: full validation
264 */
265 extern void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
266 int trylock, int read, int check,
267 struct lockdep_map *nest_lock, unsigned long ip);
268
269 extern void lock_release(struct lockdep_map *lock, unsigned long ip);
270
271 /* lock_is_held_type() returns */
272 #define LOCK_STATE_UNKNOWN -1
273 #define LOCK_STATE_NOT_HELD 0
274 #define LOCK_STATE_HELD 1
275
276 /*
277 * Same "read" as for lock_acquire(), except -1 means any.
278 */
279 extern int lock_is_held_type(const struct lockdep_map *lock, int read);
280
lock_is_held(const struct lockdep_map * lock)281 static inline int lock_is_held(const struct lockdep_map *lock)
282 {
283 return lock_is_held_type(lock, -1);
284 }
285
286 #define lockdep_is_held(lock) lock_is_held(&(lock)->dep_map)
287 #define lockdep_is_held_type(lock, r) lock_is_held_type(&(lock)->dep_map, (r))
288
289 extern void lock_set_class(struct lockdep_map *lock, const char *name,
290 struct lock_class_key *key, unsigned int subclass,
291 unsigned long ip);
292
293 #define lock_set_novalidate_class(l, n, i) \
294 lock_set_class(l, n, &__lockdep_no_validate__, 0, i)
295
lock_set_subclass(struct lockdep_map * lock,unsigned int subclass,unsigned long ip)296 static inline void lock_set_subclass(struct lockdep_map *lock,
297 unsigned int subclass, unsigned long ip)
298 {
299 lock_set_class(lock, lock->name, lock->key, subclass, ip);
300 }
301
302 extern void lock_downgrade(struct lockdep_map *lock, unsigned long ip);
303
304 #define NIL_COOKIE (struct pin_cookie){ .val = 0U, }
305
306 extern struct pin_cookie lock_pin_lock(struct lockdep_map *lock);
307 extern void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie);
308 extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);
309
310 #define lockdep_depth(tsk) (debug_locks ? (tsk)->lockdep_depth : 0)
311
312 #define lockdep_assert(cond) \
313 do { WARN_ON(debug_locks && !(cond)); } while (0)
314
315 #define lockdep_assert_once(cond) \
316 do { WARN_ON_ONCE(debug_locks && !(cond)); } while (0)
317
318 #define lockdep_assert_held(l) \
319 lockdep_assert(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
320
321 #define lockdep_assert_not_held(l) \
322 lockdep_assert(lockdep_is_held(l) != LOCK_STATE_HELD)
323
324 #define lockdep_assert_held_write(l) \
325 lockdep_assert(lockdep_is_held_type(l, 0))
326
327 #define lockdep_assert_held_read(l) \
328 lockdep_assert(lockdep_is_held_type(l, 1))
329
330 #define lockdep_assert_held_once(l) \
331 lockdep_assert_once(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
332
333 #define lockdep_assert_none_held_once() \
334 lockdep_assert_once(!current->lockdep_depth)
335
336 #define lockdep_recursing(tsk) ((tsk)->lockdep_recursion)
337
338 #define lockdep_pin_lock(l) lock_pin_lock(&(l)->dep_map)
339 #define lockdep_repin_lock(l,c) lock_repin_lock(&(l)->dep_map, (c))
340 #define lockdep_unpin_lock(l,c) lock_unpin_lock(&(l)->dep_map, (c))
341
342 #else /* !CONFIG_LOCKDEP */
343
lockdep_init_task(struct task_struct * task)344 static inline void lockdep_init_task(struct task_struct *task)
345 {
346 }
347
lockdep_off(void)348 static inline void lockdep_off(void)
349 {
350 }
351
lockdep_on(void)352 static inline void lockdep_on(void)
353 {
354 }
355
lockdep_set_selftest_task(struct task_struct * task)356 static inline void lockdep_set_selftest_task(struct task_struct *task)
357 {
358 }
359
360 # define lock_acquire(l, s, t, r, c, n, i) do { } while (0)
361 # define lock_release(l, i) do { } while (0)
362 # define lock_downgrade(l, i) do { } while (0)
363 # define lock_set_class(l, n, key, s, i) do { (void)(key); } while (0)
364 # define lock_set_novalidate_class(l, n, i) do { } while (0)
365 # define lock_set_subclass(l, s, i) do { } while (0)
366 # define lockdep_init() do { } while (0)
367 # define lockdep_init_map_type(lock, name, key, sub, inner, outer, type) \
368 do { (void)(name); (void)(key); } while (0)
369 # define lockdep_init_map_waits(lock, name, key, sub, inner, outer) \
370 do { (void)(name); (void)(key); } while (0)
371 # define lockdep_init_map_wait(lock, name, key, sub, inner) \
372 do { (void)(name); (void)(key); } while (0)
373 # define lockdep_init_map(lock, name, key, sub) \
374 do { (void)(name); (void)(key); } while (0)
375 # define lockdep_set_class(lock, key) do { (void)(key); } while (0)
376 # define lockdep_set_class_and_name(lock, key, name) \
377 do { (void)(key); (void)(name); } while (0)
378 #define lockdep_set_class_and_subclass(lock, key, sub) \
379 do { (void)(key); } while (0)
380 #define lockdep_set_subclass(lock, sub) do { } while (0)
381
382 #define lockdep_set_novalidate_class(lock) do { } while (0)
383
384 /*
385 * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP
386 * case since the result is not well defined and the caller should rather
387 * #ifdef the call himself.
388 */
389
390 # define lockdep_reset() do { debug_locks = 1; } while (0)
391 # define lockdep_free_key_range(start, size) do { } while (0)
392 # define lockdep_sys_exit() do { } while (0)
393
lockdep_register_key(struct lock_class_key * key)394 static inline void lockdep_register_key(struct lock_class_key *key)
395 {
396 }
397
lockdep_unregister_key(struct lock_class_key * key)398 static inline void lockdep_unregister_key(struct lock_class_key *key)
399 {
400 }
401
402 #define lockdep_depth(tsk) (0)
403
404 /*
405 * Dummy forward declarations, allow users to write less ifdef-y code
406 * and depend on dead code elimination.
407 */
408 extern int lock_is_held(const void *);
409 extern int lockdep_is_held(const void *);
410 #define lockdep_is_held_type(l, r) (1)
411
412 #define lockdep_assert(c) do { } while (0)
413 #define lockdep_assert_once(c) do { } while (0)
414
415 #define lockdep_assert_held(l) do { (void)(l); } while (0)
416 #define lockdep_assert_not_held(l) do { (void)(l); } while (0)
417 #define lockdep_assert_held_write(l) do { (void)(l); } while (0)
418 #define lockdep_assert_held_read(l) do { (void)(l); } while (0)
419 #define lockdep_assert_held_once(l) do { (void)(l); } while (0)
420 #define lockdep_assert_none_held_once() do { } while (0)
421
422 #define lockdep_recursing(tsk) (0)
423
424 #define NIL_COOKIE (struct pin_cookie){ }
425
426 #define lockdep_pin_lock(l) ({ struct pin_cookie cookie = { }; cookie; })
427 #define lockdep_repin_lock(l, c) do { (void)(l); (void)(c); } while (0)
428 #define lockdep_unpin_lock(l, c) do { (void)(l); (void)(c); } while (0)
429
430 #endif /* !LOCKDEP */
431
432 enum xhlock_context_t {
433 XHLOCK_HARD,
434 XHLOCK_SOFT,
435 XHLOCK_CTX_NR,
436 };
437
438 #define lockdep_init_map_crosslock(m, n, k, s) do {} while (0)
439 /*
440 * To initialize a lockdep_map statically use this macro.
441 * Note that _name must not be NULL.
442 */
443 #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \
444 { .name = (_name), .key = (void *)(_key), }
445
lockdep_invariant_state(bool force)446 static inline void lockdep_invariant_state(bool force) {}
lockdep_free_task(struct task_struct * task)447 static inline void lockdep_free_task(struct task_struct *task) {}
448
449 #ifdef CONFIG_LOCK_STAT
450
451 extern void lock_contended(struct lockdep_map *lock, unsigned long ip);
452 extern void lock_acquired(struct lockdep_map *lock, unsigned long ip);
453
454 #define LOCK_CONTENDED(_lock, try, lock) \
455 do { \
456 if (!try(_lock)) { \
457 lock_contended(&(_lock)->dep_map, _RET_IP_); \
458 lock(_lock); \
459 } \
460 lock_acquired(&(_lock)->dep_map, _RET_IP_); \
461 } while (0)
462
463 #define LOCK_CONTENDED_RETURN(_lock, try, lock) \
464 ({ \
465 int ____err = 0; \
466 if (!try(_lock)) { \
467 lock_contended(&(_lock)->dep_map, _RET_IP_); \
468 ____err = lock(_lock); \
469 } \
470 if (!____err) \
471 lock_acquired(&(_lock)->dep_map, _RET_IP_); \
472 ____err; \
473 })
474
475 #else /* CONFIG_LOCK_STAT */
476
477 #define lock_contended(lockdep_map, ip) do {} while (0)
478 #define lock_acquired(lockdep_map, ip) do {} while (0)
479
480 #define LOCK_CONTENDED(_lock, try, lock) \
481 lock(_lock)
482
483 #define LOCK_CONTENDED_RETURN(_lock, try, lock) \
484 lock(_lock)
485
486 #endif /* CONFIG_LOCK_STAT */
487
488 #ifdef CONFIG_PROVE_LOCKING
489 extern void print_irqtrace_events(struct task_struct *curr);
490 #else
print_irqtrace_events(struct task_struct * curr)491 static inline void print_irqtrace_events(struct task_struct *curr)
492 {
493 }
494 #endif
495
496 /* Variable used to make lockdep treat read_lock() as recursive in selftests */
497 #ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS
498 extern unsigned int force_read_lock_recursive;
499 #else /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
500 #define force_read_lock_recursive 0
501 #endif /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
502
503 #ifdef CONFIG_LOCKDEP
504 extern bool read_lock_is_recursive(void);
505 #else /* CONFIG_LOCKDEP */
506 /* If !LOCKDEP, the value is meaningless */
507 #define read_lock_is_recursive() 0
508 #endif
509
510 /*
511 * For trivial one-depth nesting of a lock-class, the following
512 * global define can be used. (Subsystems with multiple levels
513 * of nesting should define their own lock-nesting subclasses.)
514 */
515 #define SINGLE_DEPTH_NESTING 1
516
517 /*
518 * Map the dependency ops to NOP or to real lockdep ops, depending
519 * on the per lock-class debug mode:
520 */
521
522 #define lock_acquire_exclusive(l, s, t, n, i) lock_acquire(l, s, t, 0, 1, n, i)
523 #define lock_acquire_shared(l, s, t, n, i) lock_acquire(l, s, t, 1, 1, n, i)
524 #define lock_acquire_shared_recursive(l, s, t, n, i) lock_acquire(l, s, t, 2, 1, n, i)
525
526 #define spin_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
527 #define spin_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i)
528 #define spin_release(l, i) lock_release(l, i)
529
530 #define rwlock_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
531 #define rwlock_acquire_read(l, s, t, i) \
532 do { \
533 if (read_lock_is_recursive()) \
534 lock_acquire_shared_recursive(l, s, t, NULL, i); \
535 else \
536 lock_acquire_shared(l, s, t, NULL, i); \
537 } while (0)
538
539 #define rwlock_release(l, i) lock_release(l, i)
540
541 #define seqcount_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
542 #define seqcount_acquire_read(l, s, t, i) lock_acquire_shared_recursive(l, s, t, NULL, i)
543 #define seqcount_release(l, i) lock_release(l, i)
544
545 #define mutex_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
546 #define mutex_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i)
547 #define mutex_release(l, i) lock_release(l, i)
548
549 #define rwsem_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
550 #define rwsem_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i)
551 #define rwsem_acquire_read(l, s, t, i) lock_acquire_shared(l, s, t, NULL, i)
552 #define rwsem_release(l, i) lock_release(l, i)
553
554 #define lock_map_acquire(l) lock_acquire_exclusive(l, 0, 0, NULL, _THIS_IP_)
555 #define lock_map_acquire_read(l) lock_acquire_shared_recursive(l, 0, 0, NULL, _THIS_IP_)
556 #define lock_map_acquire_tryread(l) lock_acquire_shared_recursive(l, 0, 1, NULL, _THIS_IP_)
557 #define lock_map_release(l) lock_release(l, _THIS_IP_)
558
559 #ifdef CONFIG_PROVE_LOCKING
560 # define might_lock(lock) \
561 do { \
562 typecheck(struct lockdep_map *, &(lock)->dep_map); \
563 lock_acquire(&(lock)->dep_map, 0, 0, 0, 1, NULL, _THIS_IP_); \
564 lock_release(&(lock)->dep_map, _THIS_IP_); \
565 } while (0)
566 # define might_lock_read(lock) \
567 do { \
568 typecheck(struct lockdep_map *, &(lock)->dep_map); \
569 lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_); \
570 lock_release(&(lock)->dep_map, _THIS_IP_); \
571 } while (0)
572 # define might_lock_nested(lock, subclass) \
573 do { \
574 typecheck(struct lockdep_map *, &(lock)->dep_map); \
575 lock_acquire(&(lock)->dep_map, subclass, 0, 1, 1, NULL, \
576 _THIS_IP_); \
577 lock_release(&(lock)->dep_map, _THIS_IP_); \
578 } while (0)
579
580 DECLARE_PER_CPU(int, hardirqs_enabled);
581 DECLARE_PER_CPU(int, hardirq_context);
582 DECLARE_PER_CPU(unsigned int, lockdep_recursion);
583
584 #define __lockdep_enabled (debug_locks && !this_cpu_read(lockdep_recursion))
585
586 #define lockdep_assert_irqs_enabled() \
587 do { \
588 WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirqs_enabled)); \
589 } while (0)
590
591 #define lockdep_assert_irqs_disabled() \
592 do { \
593 WARN_ON_ONCE(__lockdep_enabled && this_cpu_read(hardirqs_enabled)); \
594 } while (0)
595
596 #define lockdep_assert_in_irq() \
597 do { \
598 WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirq_context)); \
599 } while (0)
600
601 #define lockdep_assert_preemption_enabled() \
602 do { \
603 WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \
604 __lockdep_enabled && \
605 (preempt_count() != 0 || \
606 !this_cpu_read(hardirqs_enabled))); \
607 } while (0)
608
609 #define lockdep_assert_preemption_disabled() \
610 do { \
611 WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \
612 __lockdep_enabled && \
613 (preempt_count() == 0 && \
614 this_cpu_read(hardirqs_enabled))); \
615 } while (0)
616
617 /*
618 * Acceptable for protecting per-CPU resources accessed from BH.
619 * Much like in_softirq() - semantics are ambiguous, use carefully.
620 */
621 #define lockdep_assert_in_softirq() \
622 do { \
623 WARN_ON_ONCE(__lockdep_enabled && \
624 (!in_softirq() || in_irq() || in_nmi())); \
625 } while (0)
626
627 #else
628 # define might_lock(lock) do { } while (0)
629 # define might_lock_read(lock) do { } while (0)
630 # define might_lock_nested(lock, subclass) do { } while (0)
631
632 # define lockdep_assert_irqs_enabled() do { } while (0)
633 # define lockdep_assert_irqs_disabled() do { } while (0)
634 # define lockdep_assert_in_irq() do { } while (0)
635
636 # define lockdep_assert_preemption_enabled() do { } while (0)
637 # define lockdep_assert_preemption_disabled() do { } while (0)
638 # define lockdep_assert_in_softirq() do { } while (0)
639 #endif
640
641 #ifdef CONFIG_PROVE_RAW_LOCK_NESTING
642
643 # define lockdep_assert_RT_in_threaded_ctx() do { \
644 WARN_ONCE(debug_locks && !current->lockdep_recursion && \
645 lockdep_hardirq_context() && \
646 !(current->hardirq_threaded || current->irq_config), \
647 "Not in threaded context on PREEMPT_RT as expected\n"); \
648 } while (0)
649
650 #else
651
652 # define lockdep_assert_RT_in_threaded_ctx() do { } while (0)
653
654 #endif
655
656 #ifdef CONFIG_LOCKDEP
657 void lockdep_rcu_suspicious(const char *file, const int line, const char *s);
658 #else
659 static inline void
lockdep_rcu_suspicious(const char * file,const int line,const char * s)660 lockdep_rcu_suspicious(const char *file, const int line, const char *s)
661 {
662 }
663 #endif
664
665 #endif /* __LINUX_LOCKDEP_H */
666