xref: /openbmc/linux/include/linux/lockdep.h (revision 85cfe884)
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 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  */
145 extern void lockdep_init(void);
146 extern void lockdep_reset(void);
147 extern void lockdep_reset_lock(struct lockdep_map *lock);
148 extern void lockdep_free_key_range(void *start, unsigned long size);
149 extern asmlinkage void lockdep_sys_exit(void);
150 extern void lockdep_set_selftest_task(struct task_struct *task);
151 
152 extern 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()					\
167 do {							\
168 	current->lockdep_recursion += LOCKDEP_OFF;	\
169 } while (0)
170 
171 #define lockdep_on()					\
172 do {							\
173 	current->lockdep_recursion -= LOCKDEP_OFF;	\
174 } while (0)
175 
176 extern void lockdep_register_key(struct lock_class_key *key);
177 extern 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 
185 extern 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 
188 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)189 lockdep_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, LD_LOCK_NORMAL);
193 }
194 
195 static inline void
lockdep_init_map_wait(struct lockdep_map * lock,const char * name,struct lock_class_key * key,int subclass,u8 inner)196 lockdep_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, LD_WAIT_INV);
200 }
201 
lockdep_init_map(struct lockdep_map * lock,const char * name,struct lock_class_key * key,int subclass)202 static 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, 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)->dep_map.name, (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 
lockdep_match_key(struct lockdep_map * lock,struct lock_class_key * key)246 static 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  */
266 extern 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 
270 extern void lock_release(struct lockdep_map *lock, unsigned long ip);
271 
272 extern 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  */
284 extern int lock_is_held_type(const struct lockdep_map *lock, int read);
285 
lock_is_held(const struct lockdep_map * lock)286 static inline int lock_is_held(const struct lockdep_map *lock)
287 {
288 	return lock_is_held_type(lock, -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 
294 extern 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 
lock_set_subclass(struct lockdep_map * lock,unsigned int subclass,unsigned long ip)301 static inline void lock_set_subclass(struct lockdep_map *lock,
302 		unsigned int subclass, unsigned long ip)
303 {
304 	lock_set_class(lock, lock->name, lock->key, subclass, ip);
305 }
306 
307 extern void lock_downgrade(struct lockdep_map *lock, unsigned long ip);
308 
309 #define NIL_COOKIE (struct pin_cookie){ .val = 0U, }
310 
311 extern struct pin_cookie lock_pin_lock(struct lockdep_map *lock);
312 extern void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie);
313 extern 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 
lockdep_init_task(struct task_struct * task)359 static inline void lockdep_init_task(struct task_struct *task)
360 {
361 }
362 
lockdep_off(void)363 static inline void lockdep_off(void)
364 {
365 }
366 
lockdep_on(void)367 static inline void lockdep_on(void)
368 {
369 }
370 
lockdep_set_selftest_task(struct task_struct * task)371 static 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 
lockdep_register_key(struct lock_class_key * key)409 static inline void lockdep_register_key(struct lock_class_key *key)
410 {
411 }
412 
lockdep_unregister_key(struct lock_class_key * key)413 static 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  */
423 extern int lock_is_held(const void *);
424 extern 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
451 void 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 
458 enum 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 
lockdep_invariant_state(bool force)471 static inline void lockdep_invariant_state(bool force) {}
lockdep_free_task(struct task_struct * task)472 static inline void lockdep_free_task(struct task_struct *task) {}
473 
474 #ifdef CONFIG_LOCK_STAT
475 
476 extern void lock_contended(struct lockdep_map *lock, unsigned long ip);
477 extern void lock_acquired(struct lockdep_map *lock, unsigned long ip);
478 
479 #define LOCK_CONTENDED(_lock, try, lock)			\
480 do {								\
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
514 extern void print_irqtrace_events(struct task_struct *curr);
515 #else
print_irqtrace_events(struct task_struct * curr)516 static 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
523 extern 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
529 extern 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)					\
557 do {									\
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)						\
588 do {									\
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)						\
594 do {									\
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)				\
600 do {									\
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 
607 DECLARE_PER_CPU(int, hardirqs_enabled);
608 DECLARE_PER_CPU(int, hardirq_context);
609 DECLARE_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()					\
614 do {									\
615 	WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirqs_enabled)); \
616 } while (0)
617 
618 #define lockdep_assert_irqs_disabled()					\
619 do {									\
620 	WARN_ON_ONCE(__lockdep_enabled && this_cpu_read(hardirqs_enabled)); \
621 } while (0)
622 
623 #define lockdep_assert_in_irq()						\
624 do {									\
625 	WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirq_context)); \
626 } while (0)
627 
628 #define lockdep_assert_no_hardirq()					\
629 do {									\
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()				\
635 do {									\
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()				\
643 do {									\
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()					\
655 do {									\
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
691 void lockdep_rcu_suspicious(const char *file, const int line, const char *s);
692 #else
693 static inline void
lockdep_rcu_suspicious(const char * file,const int line,const char * s)694 lockdep_rcu_suspicious(const char *file, const int line, const char *s)
695 {
696 }
697 #endif
698 
699 #endif /* __LINUX_LOCKDEP_H */
700