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
17struct 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
26static 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 */
48struct 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 */
75struct 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
89struct 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 sync:1;
138 unsigned int references:11; /* 32 bits */
139 unsigned int pin_count;
140};
141
142/*
143 * Initialization, self-test and debugging-output methods:
144 */
145extern void lockdep_init(void);
146extern void lockdep_reset(void);
147extern void lockdep_reset_lock(struct lockdep_map *lock);
148extern void lockdep_free_key_range(void *start, unsigned long size);
149extern asmlinkage void lockdep_sys_exit(void);
150extern void lockdep_set_selftest_task(struct task_struct *task);
151
152extern void lockdep_init_task(struct task_struct *task);
153
154/*
155 * Split the recursion counter in two to readily detect 'off' vs recursion.
156 */
157#define LOCKDEP_RECURSION_BITS 16
158#define LOCKDEP_OFF (1U << LOCKDEP_RECURSION_BITS)
159#define LOCKDEP_RECURSION_MASK (LOCKDEP_OFF - 1)
160
161/*
162 * lockdep_{off,on}() are macros to avoid tracing and kprobes; not inlines due
163 * to header dependencies.
164 */
165
166#define lockdep_off() \
167do { \
168 current->lockdep_recursion += LOCKDEP_OFF; \
169} while (0)
170
171#define lockdep_on() \
172do { \
173 current->lockdep_recursion -= LOCKDEP_OFF; \
174} while (0)
175
176extern void lockdep_register_key(struct lock_class_key *key);
177extern void lockdep_unregister_key(struct lock_class_key *key);
178
179/*
180 * These methods are used by specific locking variants (spinlocks,
181 * rwlocks, mutexes and rwsems) to pass init/acquire/release events
182 * to lockdep:
183 */
184
185extern void lockdep_init_map_type(struct lockdep_map *lock, const char *name,
186 struct lock_class_key *key, int subclass, u8 inner, u8 outer, u8 lock_type);
187
188static inline void
189lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
190 struct lock_class_key *key, int subclass, u8 inner, u8 outer)
191{
192 lockdep_init_map_type(lock, name, key, subclass, inner, outer, lock_type: LD_LOCK_NORMAL);
193}
194
195static inline void
196lockdep_init_map_wait(struct lockdep_map *lock, const char *name,
197 struct lock_class_key *key, int subclass, u8 inner)
198{
199 lockdep_init_map_waits(lock, name, key, subclass, inner, outer: LD_WAIT_INV);
200}
201
202static inline void lockdep_init_map(struct lockdep_map *lock, const char *name,
203 struct lock_class_key *key, int subclass)
204{
205 lockdep_init_map_wait(lock, name, key, subclass, inner: LD_WAIT_INV);
206}
207
208/*
209 * Reinitialize a lock key - for cases where there is special locking or
210 * special initialization of locks so that the validator gets the scope
211 * of dependencies wrong: they are either too broad (they need a class-split)
212 * or they are too narrow (they suffer from a false class-split):
213 */
214#define lockdep_set_class(lock, key) \
215 lockdep_init_map_type(&(lock)->dep_map, #key, key, 0, \
216 (lock)->dep_map.wait_type_inner, \
217 (lock)->dep_map.wait_type_outer, \
218 (lock)->dep_map.lock_type)
219
220#define lockdep_set_class_and_name(lock, key, name) \
221 lockdep_init_map_type(&(lock)->dep_map, name, key, 0, \
222 (lock)->dep_map.wait_type_inner, \
223 (lock)->dep_map.wait_type_outer, \
224 (lock)->dep_map.lock_type)
225
226#define lockdep_set_class_and_subclass(lock, key, sub) \
227 lockdep_init_map_type(&(lock)->dep_map, #key, key, sub, \
228 (lock)->dep_map.wait_type_inner, \
229 (lock)->dep_map.wait_type_outer, \
230 (lock)->dep_map.lock_type)
231
232#define lockdep_set_subclass(lock, sub) \
233 lockdep_init_map_type(&(lock)->dep_map, #lock, (lock)->dep_map.key, sub,\
234 (lock)->dep_map.wait_type_inner, \
235 (lock)->dep_map.wait_type_outer, \
236 (lock)->dep_map.lock_type)
237
238#define lockdep_set_novalidate_class(lock) \
239 lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock)
240
241/*
242 * Compare locking classes
243 */
244#define lockdep_match_class(lock, key) lockdep_match_key(&(lock)->dep_map, key)
245
246static inline int lockdep_match_key(struct lockdep_map *lock,
247 struct lock_class_key *key)
248{
249 return lock->key == key;
250}
251
252/*
253 * Acquire a lock.
254 *
255 * Values for "read":
256 *
257 * 0: exclusive (write) acquire
258 * 1: read-acquire (no recursion allowed)
259 * 2: read-acquire with same-instance recursion allowed
260 *
261 * Values for check:
262 *
263 * 0: simple checks (freeing, held-at-exit-time, etc.)
264 * 1: full validation
265 */
266extern void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
267 int trylock, int read, int check,
268 struct lockdep_map *nest_lock, unsigned long ip);
269
270extern void lock_release(struct lockdep_map *lock, unsigned long ip);
271
272extern void lock_sync(struct lockdep_map *lock, unsigned int subclass,
273 int read, int check, struct lockdep_map *nest_lock,
274 unsigned long ip);
275
276/* lock_is_held_type() returns */
277#define LOCK_STATE_UNKNOWN -1
278#define LOCK_STATE_NOT_HELD 0
279#define LOCK_STATE_HELD 1
280
281/*
282 * Same "read" as for lock_acquire(), except -1 means any.
283 */
284extern int lock_is_held_type(const struct lockdep_map *lock, int read);
285
286static inline int lock_is_held(const struct lockdep_map *lock)
287{
288 return lock_is_held_type(lock, read: -1);
289}
290
291#define lockdep_is_held(lock) lock_is_held(&(lock)->dep_map)
292#define lockdep_is_held_type(lock, r) lock_is_held_type(&(lock)->dep_map, (r))
293
294extern void lock_set_class(struct lockdep_map *lock, const char *name,
295 struct lock_class_key *key, unsigned int subclass,
296 unsigned long ip);
297
298#define lock_set_novalidate_class(l, n, i) \
299 lock_set_class(l, n, &__lockdep_no_validate__, 0, i)
300
301static inline void lock_set_subclass(struct lockdep_map *lock,
302 unsigned int subclass, unsigned long ip)
303{
304 lock_set_class(lock, name: lock->name, key: lock->key, subclass, ip);
305}
306
307extern void lock_downgrade(struct lockdep_map *lock, unsigned long ip);
308
309#define NIL_COOKIE (struct pin_cookie){ .val = 0U, }
310
311extern struct pin_cookie lock_pin_lock(struct lockdep_map *lock);
312extern void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie);
313extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);
314
315#define lockdep_depth(tsk) (debug_locks ? (tsk)->lockdep_depth : 0)
316
317#define lockdep_assert(cond) \
318 do { WARN_ON(debug_locks && !(cond)); } while (0)
319
320#define lockdep_assert_once(cond) \
321 do { WARN_ON_ONCE(debug_locks && !(cond)); } while (0)
322
323#define lockdep_assert_held(l) \
324 lockdep_assert(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
325
326#define lockdep_assert_not_held(l) \
327 lockdep_assert(lockdep_is_held(l) != LOCK_STATE_HELD)
328
329#define lockdep_assert_held_write(l) \
330 lockdep_assert(lockdep_is_held_type(l, 0))
331
332#define lockdep_assert_held_read(l) \
333 lockdep_assert(lockdep_is_held_type(l, 1))
334
335#define lockdep_assert_held_once(l) \
336 lockdep_assert_once(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
337
338#define lockdep_assert_none_held_once() \
339 lockdep_assert_once(!current->lockdep_depth)
340
341#define lockdep_recursing(tsk) ((tsk)->lockdep_recursion)
342
343#define lockdep_pin_lock(l) lock_pin_lock(&(l)->dep_map)
344#define lockdep_repin_lock(l,c) lock_repin_lock(&(l)->dep_map, (c))
345#define lockdep_unpin_lock(l,c) lock_unpin_lock(&(l)->dep_map, (c))
346
347/*
348 * Must use lock_map_aquire_try() with override maps to avoid
349 * lockdep thinking they participate in the block chain.
350 */
351#define DEFINE_WAIT_OVERRIDE_MAP(_name, _wait_type) \
352 struct lockdep_map _name = { \
353 .name = #_name "-wait-type-override", \
354 .wait_type_inner = _wait_type, \
355 .lock_type = LD_LOCK_WAIT_OVERRIDE, }
356
357#else /* !CONFIG_LOCKDEP */
358
359static inline void lockdep_init_task(struct task_struct *task)
360{
361}
362
363static inline void lockdep_off(void)
364{
365}
366
367static inline void lockdep_on(void)
368{
369}
370
371static inline void lockdep_set_selftest_task(struct task_struct *task)
372{
373}
374
375# define lock_acquire(l, s, t, r, c, n, i) do { } while (0)
376# define lock_release(l, i) do { } while (0)
377# define lock_downgrade(l, i) do { } while (0)
378# define lock_set_class(l, n, key, s, i) do { (void)(key); } while (0)
379# define lock_set_novalidate_class(l, n, i) do { } while (0)
380# define lock_set_subclass(l, s, i) do { } while (0)
381# define lockdep_init() do { } while (0)
382# define lockdep_init_map_type(lock, name, key, sub, inner, outer, type) \
383 do { (void)(name); (void)(key); } while (0)
384# define lockdep_init_map_waits(lock, name, key, sub, inner, outer) \
385 do { (void)(name); (void)(key); } while (0)
386# define lockdep_init_map_wait(lock, name, key, sub, inner) \
387 do { (void)(name); (void)(key); } while (0)
388# define lockdep_init_map(lock, name, key, sub) \
389 do { (void)(name); (void)(key); } while (0)
390# define lockdep_set_class(lock, key) do { (void)(key); } while (0)
391# define lockdep_set_class_and_name(lock, key, name) \
392 do { (void)(key); (void)(name); } while (0)
393#define lockdep_set_class_and_subclass(lock, key, sub) \
394 do { (void)(key); } while (0)
395#define lockdep_set_subclass(lock, sub) do { } while (0)
396
397#define lockdep_set_novalidate_class(lock) do { } while (0)
398
399/*
400 * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP
401 * case since the result is not well defined and the caller should rather
402 * #ifdef the call himself.
403 */
404
405# define lockdep_reset() do { debug_locks = 1; } while (0)
406# define lockdep_free_key_range(start, size) do { } while (0)
407# define lockdep_sys_exit() do { } while (0)
408
409static inline void lockdep_register_key(struct lock_class_key *key)
410{
411}
412
413static inline void lockdep_unregister_key(struct lock_class_key *key)
414{
415}
416
417#define lockdep_depth(tsk) (0)
418
419/*
420 * Dummy forward declarations, allow users to write less ifdef-y code
421 * and depend on dead code elimination.
422 */
423extern int lock_is_held(const void *);
424extern int lockdep_is_held(const void *);
425#define lockdep_is_held_type(l, r) (1)
426
427#define lockdep_assert(c) do { } while (0)
428#define lockdep_assert_once(c) do { } while (0)
429
430#define lockdep_assert_held(l) do { (void)(l); } while (0)
431#define lockdep_assert_not_held(l) do { (void)(l); } while (0)
432#define lockdep_assert_held_write(l) do { (void)(l); } while (0)
433#define lockdep_assert_held_read(l) do { (void)(l); } while (0)
434#define lockdep_assert_held_once(l) do { (void)(l); } while (0)
435#define lockdep_assert_none_held_once() do { } while (0)
436
437#define lockdep_recursing(tsk) (0)
438
439#define NIL_COOKIE (struct pin_cookie){ }
440
441#define lockdep_pin_lock(l) ({ struct pin_cookie cookie = { }; cookie; })
442#define lockdep_repin_lock(l, c) do { (void)(l); (void)(c); } while (0)
443#define lockdep_unpin_lock(l, c) do { (void)(l); (void)(c); } while (0)
444
445#define DEFINE_WAIT_OVERRIDE_MAP(_name, _wait_type) \
446 struct lockdep_map __maybe_unused _name = {}
447
448#endif /* !LOCKDEP */
449
450#ifdef CONFIG_PROVE_LOCKING
451void lockdep_set_lock_cmp_fn(struct lockdep_map *, lock_cmp_fn, lock_print_fn);
452
453#define lock_set_cmp_fn(lock, ...) lockdep_set_lock_cmp_fn(&(lock)->dep_map, __VA_ARGS__)
454#else
455#define lock_set_cmp_fn(lock, ...) do { } while (0)
456#endif
457
458enum xhlock_context_t {
459 XHLOCK_HARD,
460 XHLOCK_SOFT,
461 XHLOCK_CTX_NR,
462};
463
464/*
465 * To initialize a lockdep_map statically use this macro.
466 * Note that _name must not be NULL.
467 */
468#define STATIC_LOCKDEP_MAP_INIT(_name, _key) \
469 { .name = (_name), .key = (void *)(_key), }
470
471static inline void lockdep_invariant_state(bool force) {}
472static inline void lockdep_free_task(struct task_struct *task) {}
473
474#ifdef CONFIG_LOCK_STAT
475
476extern void lock_contended(struct lockdep_map *lock, unsigned long ip);
477extern void lock_acquired(struct lockdep_map *lock, unsigned long ip);
478
479#define LOCK_CONTENDED(_lock, try, lock) \
480do { \
481 if (!try(_lock)) { \
482 lock_contended(&(_lock)->dep_map, _RET_IP_); \
483 lock(_lock); \
484 } \
485 lock_acquired(&(_lock)->dep_map, _RET_IP_); \
486} while (0)
487
488#define LOCK_CONTENDED_RETURN(_lock, try, lock) \
489({ \
490 int ____err = 0; \
491 if (!try(_lock)) { \
492 lock_contended(&(_lock)->dep_map, _RET_IP_); \
493 ____err = lock(_lock); \
494 } \
495 if (!____err) \
496 lock_acquired(&(_lock)->dep_map, _RET_IP_); \
497 ____err; \
498})
499
500#else /* CONFIG_LOCK_STAT */
501
502#define lock_contended(lockdep_map, ip) do {} while (0)
503#define lock_acquired(lockdep_map, ip) do {} while (0)
504
505#define LOCK_CONTENDED(_lock, try, lock) \
506 lock(_lock)
507
508#define LOCK_CONTENDED_RETURN(_lock, try, lock) \
509 lock(_lock)
510
511#endif /* CONFIG_LOCK_STAT */
512
513#ifdef CONFIG_PROVE_LOCKING
514extern void print_irqtrace_events(struct task_struct *curr);
515#else
516static inline void print_irqtrace_events(struct task_struct *curr)
517{
518}
519#endif
520
521/* Variable used to make lockdep treat read_lock() as recursive in selftests */
522#ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS
523extern unsigned int force_read_lock_recursive;
524#else /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
525#define force_read_lock_recursive 0
526#endif /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
527
528#ifdef CONFIG_LOCKDEP
529extern bool read_lock_is_recursive(void);
530#else /* CONFIG_LOCKDEP */
531/* If !LOCKDEP, the value is meaningless */
532#define read_lock_is_recursive() 0
533#endif
534
535/*
536 * For trivial one-depth nesting of a lock-class, the following
537 * global define can be used. (Subsystems with multiple levels
538 * of nesting should define their own lock-nesting subclasses.)
539 */
540#define SINGLE_DEPTH_NESTING 1
541
542/*
543 * Map the dependency ops to NOP or to real lockdep ops, depending
544 * on the per lock-class debug mode:
545 */
546
547#define lock_acquire_exclusive(l, s, t, n, i) lock_acquire(l, s, t, 0, 1, n, i)
548#define lock_acquire_shared(l, s, t, n, i) lock_acquire(l, s, t, 1, 1, n, i)
549#define lock_acquire_shared_recursive(l, s, t, n, i) lock_acquire(l, s, t, 2, 1, n, i)
550
551#define spin_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
552#define spin_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i)
553#define spin_release(l, i) lock_release(l, i)
554
555#define rwlock_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
556#define rwlock_acquire_read(l, s, t, i) \
557do { \
558 if (read_lock_is_recursive()) \
559 lock_acquire_shared_recursive(l, s, t, NULL, i); \
560 else \
561 lock_acquire_shared(l, s, t, NULL, i); \
562} while (0)
563
564#define rwlock_release(l, i) lock_release(l, i)
565
566#define seqcount_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
567#define seqcount_acquire_read(l, s, t, i) lock_acquire_shared_recursive(l, s, t, NULL, i)
568#define seqcount_release(l, i) lock_release(l, i)
569
570#define mutex_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
571#define mutex_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i)
572#define mutex_release(l, i) lock_release(l, i)
573
574#define rwsem_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i)
575#define rwsem_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i)
576#define rwsem_acquire_read(l, s, t, i) lock_acquire_shared(l, s, t, NULL, i)
577#define rwsem_release(l, i) lock_release(l, i)
578
579#define lock_map_acquire(l) lock_acquire_exclusive(l, 0, 0, NULL, _THIS_IP_)
580#define lock_map_acquire_try(l) lock_acquire_exclusive(l, 0, 1, NULL, _THIS_IP_)
581#define lock_map_acquire_read(l) lock_acquire_shared_recursive(l, 0, 0, NULL, _THIS_IP_)
582#define lock_map_acquire_tryread(l) lock_acquire_shared_recursive(l, 0, 1, NULL, _THIS_IP_)
583#define lock_map_release(l) lock_release(l, _THIS_IP_)
584#define lock_map_sync(l) lock_sync(l, 0, 0, 1, NULL, _THIS_IP_)
585
586#ifdef CONFIG_PROVE_LOCKING
587# define might_lock(lock) \
588do { \
589 typecheck(struct lockdep_map *, &(lock)->dep_map); \
590 lock_acquire(&(lock)->dep_map, 0, 0, 0, 1, NULL, _THIS_IP_); \
591 lock_release(&(lock)->dep_map, _THIS_IP_); \
592} while (0)
593# define might_lock_read(lock) \
594do { \
595 typecheck(struct lockdep_map *, &(lock)->dep_map); \
596 lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_); \
597 lock_release(&(lock)->dep_map, _THIS_IP_); \
598} while (0)
599# define might_lock_nested(lock, subclass) \
600do { \
601 typecheck(struct lockdep_map *, &(lock)->dep_map); \
602 lock_acquire(&(lock)->dep_map, subclass, 0, 1, 1, NULL, \
603 _THIS_IP_); \
604 lock_release(&(lock)->dep_map, _THIS_IP_); \
605} while (0)
606
607DECLARE_PER_CPU(int, hardirqs_enabled);
608DECLARE_PER_CPU(int, hardirq_context);
609DECLARE_PER_CPU(unsigned int, lockdep_recursion);
610
611#define __lockdep_enabled (debug_locks && !this_cpu_read(lockdep_recursion))
612
613#define lockdep_assert_irqs_enabled() \
614do { \
615 WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirqs_enabled)); \
616} while (0)
617
618#define lockdep_assert_irqs_disabled() \
619do { \
620 WARN_ON_ONCE(__lockdep_enabled && this_cpu_read(hardirqs_enabled)); \
621} while (0)
622
623#define lockdep_assert_in_irq() \
624do { \
625 WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirq_context)); \
626} while (0)
627
628#define lockdep_assert_no_hardirq() \
629do { \
630 WARN_ON_ONCE(__lockdep_enabled && (this_cpu_read(hardirq_context) || \
631 !this_cpu_read(hardirqs_enabled))); \
632} while (0)
633
634#define lockdep_assert_preemption_enabled() \
635do { \
636 WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \
637 __lockdep_enabled && \
638 (preempt_count() != 0 || \
639 !this_cpu_read(hardirqs_enabled))); \
640} while (0)
641
642#define lockdep_assert_preemption_disabled() \
643do { \
644 WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \
645 __lockdep_enabled && \
646 (preempt_count() == 0 && \
647 this_cpu_read(hardirqs_enabled))); \
648} while (0)
649
650/*
651 * Acceptable for protecting per-CPU resources accessed from BH.
652 * Much like in_softirq() - semantics are ambiguous, use carefully.
653 */
654#define lockdep_assert_in_softirq() \
655do { \
656 WARN_ON_ONCE(__lockdep_enabled && \
657 (!in_softirq() || in_irq() || in_nmi())); \
658} while (0)
659
660#else
661# define might_lock(lock) do { } while (0)
662# define might_lock_read(lock) do { } while (0)
663# define might_lock_nested(lock, subclass) do { } while (0)
664
665# define lockdep_assert_irqs_enabled() do { } while (0)
666# define lockdep_assert_irqs_disabled() do { } while (0)
667# define lockdep_assert_in_irq() do { } while (0)
668# define lockdep_assert_no_hardirq() do { } while (0)
669
670# define lockdep_assert_preemption_enabled() do { } while (0)
671# define lockdep_assert_preemption_disabled() do { } while (0)
672# define lockdep_assert_in_softirq() do { } while (0)
673#endif
674
675#ifdef CONFIG_PROVE_RAW_LOCK_NESTING
676
677# define lockdep_assert_RT_in_threaded_ctx() do { \
678 WARN_ONCE(debug_locks && !current->lockdep_recursion && \
679 lockdep_hardirq_context() && \
680 !(current->hardirq_threaded || current->irq_config), \
681 "Not in threaded context on PREEMPT_RT as expected\n"); \
682} while (0)
683
684#else
685
686# define lockdep_assert_RT_in_threaded_ctx() do { } while (0)
687
688#endif
689
690#ifdef CONFIG_LOCKDEP
691void lockdep_rcu_suspicious(const char *file, const int line, const char *s);
692#else
693static inline void
694lockdep_rcu_suspicious(const char *file, const int line, const char *s)
695{
696}
697#endif
698
699#endif /* __LINUX_LOCKDEP_H */
700

source code of linux/include/linux/lockdep.h