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 struct task_struct;
14 struct lockdep_map;
15 
16 /* for sysctl */
17 extern int prove_locking;
18 extern int lock_stat;
19 
20 #define MAX_LOCKDEP_SUBCLASSES		8UL
21 
22 #include <linux/types.h>
23 
24 #ifdef CONFIG_LOCKDEP
25 
26 #include <linux/linkage.h>
27 #include <linux/list.h>
28 #include <linux/debug_locks.h>
29 #include <linux/stacktrace.h>
30 
31 /*
32  * We'd rather not expose kernel/lockdep_states.h this wide, but we do need
33  * the total number of states... :-(
34  */
35 #define XXX_LOCK_USAGE_STATES		(1+2*4)
36 
37 /*
38  * NR_LOCKDEP_CACHING_CLASSES ... Number of classes
39  * cached in the instance of lockdep_map
40  *
41  * Currently main class (subclass == 0) and signle depth subclass
42  * are cached in lockdep_map. This optimization is mainly targeting
43  * on rq->lock. double_rq_lock() acquires this highly competitive with
44  * single depth.
45  */
46 #define NR_LOCKDEP_CACHING_CLASSES	2
47 
48 /*
49  * A lockdep key is associated with each lock object. For static locks we use
50  * the lock address itself as the key. Dynamically allocated lock objects can
51  * have a statically or dynamically allocated key. Dynamically allocated lock
52  * keys must be registered before being used and must be unregistered before
53  * the key memory is freed.
54  */
55 struct lockdep_subclass_key {
56 	char __one_byte;
57 } __attribute__ ((__packed__));
58 
59 /* hash_entry is used to keep track of dynamically allocated keys. */
60 struct lock_class_key {
61 	union {
62 		struct hlist_node		hash_entry;
63 		struct lockdep_subclass_key	subkeys[MAX_LOCKDEP_SUBCLASSES];
64 	};
65 };
66 
67 extern struct lock_class_key __lockdep_no_validate__;
68 
69 struct lock_trace;
70 
71 #define LOCKSTAT_POINTS		4
72 
73 /*
74  * The lock-class itself. The order of the structure members matters.
75  * reinit_class() zeroes the key member and all subsequent members.
76  */
77 struct lock_class {
78 	/*
79 	 * class-hash:
80 	 */
81 	struct hlist_node		hash_entry;
82 
83 	/*
84 	 * Entry in all_lock_classes when in use. Entry in free_lock_classes
85 	 * when not in use. Instances that are being freed are on one of the
86 	 * zapped_classes lists.
87 	 */
88 	struct list_head		lock_entry;
89 
90 	/*
91 	 * These fields represent a directed graph of lock dependencies,
92 	 * to every node we attach a list of "forward" and a list of
93 	 * "backward" graph nodes.
94 	 */
95 	struct list_head		locks_after, locks_before;
96 
97 	const struct lockdep_subclass_key *key;
98 	unsigned int			subclass;
99 	unsigned int			dep_gen_id;
100 
101 	/*
102 	 * IRQ/softirq usage tracking bits:
103 	 */
104 	unsigned long			usage_mask;
105 	const struct lock_trace		*usage_traces[XXX_LOCK_USAGE_STATES];
106 
107 	/*
108 	 * Generation counter, when doing certain classes of graph walking,
109 	 * to ensure that we check one node only once:
110 	 */
111 	int				name_version;
112 	const char			*name;
113 
114 #ifdef CONFIG_LOCK_STAT
115 	unsigned long			contention_point[LOCKSTAT_POINTS];
116 	unsigned long			contending_point[LOCKSTAT_POINTS];
117 #endif
118 } __no_randomize_layout;
119 
120 #ifdef CONFIG_LOCK_STAT
121 struct lock_time {
122 	s64				min;
123 	s64				max;
124 	s64				total;
125 	unsigned long			nr;
126 };
127 
128 enum bounce_type {
129 	bounce_acquired_write,
130 	bounce_acquired_read,
131 	bounce_contended_write,
132 	bounce_contended_read,
133 	nr_bounce_types,
134 
135 	bounce_acquired = bounce_acquired_write,
136 	bounce_contended = bounce_contended_write,
137 };
138 
139 struct lock_class_stats {
140 	unsigned long			contention_point[LOCKSTAT_POINTS];
141 	unsigned long			contending_point[LOCKSTAT_POINTS];
142 	struct lock_time		read_waittime;
143 	struct lock_time		write_waittime;
144 	struct lock_time		read_holdtime;
145 	struct lock_time		write_holdtime;
146 	unsigned long			bounces[nr_bounce_types];
147 };
148 
149 struct lock_class_stats lock_stats(struct lock_class *class);
150 void clear_lock_stats(struct lock_class *class);
151 #endif
152 
153 /*
154  * Map the lock object (the lock instance) to the lock-class object.
155  * This is embedded into specific lock instances:
156  */
157 struct lockdep_map {
158 	struct lock_class_key		*key;
159 	struct lock_class		*class_cache[NR_LOCKDEP_CACHING_CLASSES];
160 	const char			*name;
161 #ifdef CONFIG_LOCK_STAT
162 	int				cpu;
163 	unsigned long			ip;
164 #endif
165 };
166 
lockdep_copy_map(struct lockdep_map * to,struct lockdep_map * from)167 static inline void lockdep_copy_map(struct lockdep_map *to,
168 				    struct lockdep_map *from)
169 {
170 	int i;
171 
172 	*to = *from;
173 	/*
174 	 * Since the class cache can be modified concurrently we could observe
175 	 * half pointers (64bit arch using 32bit copy insns). Therefore clear
176 	 * the caches and take the performance hit.
177 	 *
178 	 * XXX it doesn't work well with lockdep_set_class_and_subclass(), since
179 	 *     that relies on cache abuse.
180 	 */
181 	for (i = 0; i < NR_LOCKDEP_CACHING_CLASSES; i++)
182 		to->class_cache[i] = NULL;
183 }
184 
185 /*
186  * Every lock has a list of other locks that were taken after it.
187  * We only grow the list, never remove from it:
188  */
189 struct lock_list {
190 	struct list_head		entry;
191 	struct lock_class		*class;
192 	struct lock_class		*links_to;
193 	const struct lock_trace		*trace;
194 	int				distance;
195 
196 	/*
197 	 * The parent field is used to implement breadth-first search, and the
198 	 * bit 0 is reused to indicate if the lock has been accessed in BFS.
199 	 */
200 	struct lock_list		*parent;
201 };
202 
203 /**
204  * struct lock_chain - lock dependency chain record
205  *
206  * @irq_context: the same as irq_context in held_lock below
207  * @depth:       the number of held locks in this chain
208  * @base:        the index in chain_hlocks for this chain
209  * @entry:       the collided lock chains in lock_chain hash list
210  * @chain_key:   the hash key of this lock_chain
211  */
212 struct lock_chain {
213 	/* see BUILD_BUG_ON()s in add_chain_cache() */
214 	unsigned int			irq_context :  2,
215 					depth       :  6,
216 					base	    : 24;
217 	/* 4 byte hole */
218 	struct hlist_node		entry;
219 	u64				chain_key;
220 };
221 
222 #define MAX_LOCKDEP_KEYS_BITS		13
223 #define MAX_LOCKDEP_KEYS		(1UL << MAX_LOCKDEP_KEYS_BITS)
224 #define INITIAL_CHAIN_KEY		-1
225 
226 struct held_lock {
227 	/*
228 	 * One-way hash of the dependency chain up to this point. We
229 	 * hash the hashes step by step as the dependency chain grows.
230 	 *
231 	 * We use it for dependency-caching and we skip detection
232 	 * passes and dependency-updates if there is a cache-hit, so
233 	 * it is absolutely critical for 100% coverage of the validator
234 	 * to have a unique key value for every unique dependency path
235 	 * that can occur in the system, to make a unique hash value
236 	 * as likely as possible - hence the 64-bit width.
237 	 *
238 	 * The task struct holds the current hash value (initialized
239 	 * with zero), here we store the previous hash value:
240 	 */
241 	u64				prev_chain_key;
242 	unsigned long			acquire_ip;
243 	struct lockdep_map		*instance;
244 	struct lockdep_map		*nest_lock;
245 #ifdef CONFIG_LOCK_STAT
246 	u64 				waittime_stamp;
247 	u64				holdtime_stamp;
248 #endif
249 	/*
250 	 * class_idx is zero-indexed; it points to the element in
251 	 * lock_classes this held lock instance belongs to. class_idx is in
252 	 * the range from 0 to (MAX_LOCKDEP_KEYS-1) inclusive.
253 	 */
254 	unsigned int			class_idx:MAX_LOCKDEP_KEYS_BITS;
255 	/*
256 	 * The lock-stack is unified in that the lock chains of interrupt
257 	 * contexts nest ontop of process context chains, but we 'separate'
258 	 * the hashes by starting with 0 if we cross into an interrupt
259 	 * context, and we also keep do not add cross-context lock
260 	 * dependencies - the lock usage graph walking covers that area
261 	 * anyway, and we'd just unnecessarily increase the number of
262 	 * dependencies otherwise. [Note: hardirq and softirq contexts
263 	 * are separated from each other too.]
264 	 *
265 	 * The following field is used to detect when we cross into an
266 	 * interrupt context:
267 	 */
268 	unsigned int irq_context:2; /* bit 0 - soft, bit 1 - hard */
269 	unsigned int trylock:1;						/* 16 bits */
270 
271 	unsigned int read:2;        /* see lock_acquire() comment */
272 	unsigned int check:1;       /* see lock_acquire() comment */
273 	unsigned int hardirqs_off:1;
274 	unsigned int references:12;					/* 32 bits */
275 	unsigned int pin_count;
276 };
277 
278 /*
279  * Initialization, self-test and debugging-output methods:
280  */
281 extern void lockdep_init(void);
282 extern void lockdep_reset(void);
283 extern void lockdep_reset_lock(struct lockdep_map *lock);
284 extern void lockdep_free_key_range(void *start, unsigned long size);
285 extern asmlinkage void lockdep_sys_exit(void);
286 extern void lockdep_set_selftest_task(struct task_struct *task);
287 
288 extern void lockdep_init_task(struct task_struct *task);
289 
290 extern void lockdep_off(void);
291 extern void lockdep_on(void);
292 
293 extern void lockdep_register_key(struct lock_class_key *key);
294 extern void lockdep_unregister_key(struct lock_class_key *key);
295 
296 /*
297  * These methods are used by specific locking variants (spinlocks,
298  * rwlocks, mutexes and rwsems) to pass init/acquire/release events
299  * to lockdep:
300  */
301 
302 extern void lockdep_init_map(struct lockdep_map *lock, const char *name,
303 			     struct lock_class_key *key, int subclass);
304 
305 /*
306  * Reinitialize a lock key - for cases where there is special locking or
307  * special initialization of locks so that the validator gets the scope
308  * of dependencies wrong: they are either too broad (they need a class-split)
309  * or they are too narrow (they suffer from a false class-split):
310  */
311 #define lockdep_set_class(lock, key) \
312 		lockdep_init_map(&(lock)->dep_map, #key, key, 0)
313 #define lockdep_set_class_and_name(lock, key, name) \
314 		lockdep_init_map(&(lock)->dep_map, name, key, 0)
315 #define lockdep_set_class_and_subclass(lock, key, sub) \
316 		lockdep_init_map(&(lock)->dep_map, #key, key, sub)
317 #define lockdep_set_subclass(lock, sub)	\
318 		lockdep_init_map(&(lock)->dep_map, #lock, \
319 				 (lock)->dep_map.key, sub)
320 
321 #define lockdep_set_novalidate_class(lock) \
322 	lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock)
323 /*
324  * Compare locking classes
325  */
326 #define lockdep_match_class(lock, key) lockdep_match_key(&(lock)->dep_map, key)
327 
lockdep_match_key(struct lockdep_map * lock,struct lock_class_key * key)328 static inline int lockdep_match_key(struct lockdep_map *lock,
329 				    struct lock_class_key *key)
330 {
331 	return lock->key == key;
332 }
333 
334 /*
335  * Acquire a lock.
336  *
337  * Values for "read":
338  *
339  *   0: exclusive (write) acquire
340  *   1: read-acquire (no recursion allowed)
341  *   2: read-acquire with same-instance recursion allowed
342  *
343  * Values for check:
344  *
345  *   0: simple checks (freeing, held-at-exit-time, etc.)
346  *   1: full validation
347  */
348 extern void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
349 			 int trylock, int read, int check,
350 			 struct lockdep_map *nest_lock, unsigned long ip);
351 
352 extern void lock_release(struct lockdep_map *lock, int nested,
353 			 unsigned long ip);
354 
355 /*
356  * Same "read" as for lock_acquire(), except -1 means any.
357  */
358 extern int lock_is_held_type(const struct lockdep_map *lock, int read);
359 
lock_is_held(const struct lockdep_map * lock)360 static inline int lock_is_held(const struct lockdep_map *lock)
361 {
362 	return lock_is_held_type(lock, -1);
363 }
364 
365 #define lockdep_is_held(lock)		lock_is_held(&(lock)->dep_map)
366 #define lockdep_is_held_type(lock, r)	lock_is_held_type(&(lock)->dep_map, (r))
367 
368 extern void lock_set_class(struct lockdep_map *lock, const char *name,
369 			   struct lock_class_key *key, unsigned int subclass,
370 			   unsigned long ip);
371 
lock_set_subclass(struct lockdep_map * lock,unsigned int subclass,unsigned long ip)372 static inline void lock_set_subclass(struct lockdep_map *lock,
373 		unsigned int subclass, unsigned long ip)
374 {
375 	lock_set_class(lock, lock->name, lock->key, subclass, ip);
376 }
377 
378 extern void lock_downgrade(struct lockdep_map *lock, unsigned long ip);
379 
380 struct pin_cookie { unsigned int val; };
381 
382 #define NIL_COOKIE (struct pin_cookie){ .val = 0U, }
383 
384 extern struct pin_cookie lock_pin_lock(struct lockdep_map *lock);
385 extern void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie);
386 extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);
387 
388 #define lockdep_depth(tsk)	(debug_locks ? (tsk)->lockdep_depth : 0)
389 
390 #define lockdep_assert_held(l)	do {				\
391 		WARN_ON(debug_locks && !lockdep_is_held(l));	\
392 	} while (0)
393 
394 #define lockdep_assert_held_write(l)	do {			\
395 		WARN_ON(debug_locks && !lockdep_is_held_type(l, 0));	\
396 	} while (0)
397 
398 #define lockdep_assert_held_read(l)	do {				\
399 		WARN_ON(debug_locks && !lockdep_is_held_type(l, 1));	\
400 	} while (0)
401 
402 #define lockdep_assert_held_once(l)	do {				\
403 		WARN_ON_ONCE(debug_locks && !lockdep_is_held(l));	\
404 	} while (0)
405 
406 #define lockdep_recursing(tsk)	((tsk)->lockdep_recursion)
407 
408 #define lockdep_pin_lock(l)	lock_pin_lock(&(l)->dep_map)
409 #define lockdep_repin_lock(l,c)	lock_repin_lock(&(l)->dep_map, (c))
410 #define lockdep_unpin_lock(l,c)	lock_unpin_lock(&(l)->dep_map, (c))
411 
412 #else /* !CONFIG_LOCKDEP */
413 
lockdep_init_task(struct task_struct * task)414 static inline void lockdep_init_task(struct task_struct *task)
415 {
416 }
417 
lockdep_off(void)418 static inline void lockdep_off(void)
419 {
420 }
421 
lockdep_on(void)422 static inline void lockdep_on(void)
423 {
424 }
425 
lockdep_set_selftest_task(struct task_struct * task)426 static inline void lockdep_set_selftest_task(struct task_struct *task)
427 {
428 }
429 
430 # define lock_acquire(l, s, t, r, c, n, i)	do { } while (0)
431 # define lock_release(l, n, i)			do { } while (0)
432 # define lock_downgrade(l, i)			do { } while (0)
433 # define lock_set_class(l, n, k, s, i)		do { } while (0)
434 # define lock_set_subclass(l, s, i)		do { } while (0)
435 # define lockdep_init()				do { } while (0)
436 # define lockdep_init_map(lock, name, key, sub) \
437 		do { (void)(name); (void)(key); } while (0)
438 # define lockdep_set_class(lock, key)		do { (void)(key); } while (0)
439 # define lockdep_set_class_and_name(lock, key, name) \
440 		do { (void)(key); (void)(name); } while (0)
441 #define lockdep_set_class_and_subclass(lock, key, sub) \
442 		do { (void)(key); } while (0)
443 #define lockdep_set_subclass(lock, sub)		do { } while (0)
444 
445 #define lockdep_set_novalidate_class(lock) do { } while (0)
446 
447 /*
448  * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP
449  * case since the result is not well defined and the caller should rather
450  * #ifdef the call himself.
451  */
452 
453 # define lockdep_reset()		do { debug_locks = 1; } while (0)
454 # define lockdep_free_key_range(start, size)	do { } while (0)
455 # define lockdep_sys_exit() 			do { } while (0)
456 /*
457  * The class key takes no space if lockdep is disabled:
458  */
459 struct lock_class_key { };
460 
lockdep_register_key(struct lock_class_key * key)461 static inline void lockdep_register_key(struct lock_class_key *key)
462 {
463 }
464 
lockdep_unregister_key(struct lock_class_key * key)465 static inline void lockdep_unregister_key(struct lock_class_key *key)
466 {
467 }
468 
469 /*
470  * The lockdep_map takes no space if lockdep is disabled:
471  */
472 struct lockdep_map { };
473 
474 #define lockdep_depth(tsk)	(0)
475 
476 #define lockdep_is_held_type(l, r)		(1)
477 
478 #define lockdep_assert_held(l)			do { (void)(l); } while (0)
479 #define lockdep_assert_held_write(l)	do { (void)(l); } while (0)
480 #define lockdep_assert_held_read(l)		do { (void)(l); } while (0)
481 #define lockdep_assert_held_once(l)		do { (void)(l); } while (0)
482 
483 #define lockdep_recursing(tsk)			(0)
484 
485 struct pin_cookie { };
486 
487 #define NIL_COOKIE (struct pin_cookie){ }
488 
489 #define lockdep_pin_lock(l)			({ struct pin_cookie cookie = { }; cookie; })
490 #define lockdep_repin_lock(l, c)		do { (void)(l); (void)(c); } while (0)
491 #define lockdep_unpin_lock(l, c)		do { (void)(l); (void)(c); } while (0)
492 
493 #endif /* !LOCKDEP */
494 
495 enum xhlock_context_t {
496 	XHLOCK_HARD,
497 	XHLOCK_SOFT,
498 	XHLOCK_CTX_NR,
499 };
500 
501 #define lockdep_init_map_crosslock(m, n, k, s) do {} while (0)
502 /*
503  * To initialize a lockdep_map statically use this macro.
504  * Note that _name must not be NULL.
505  */
506 #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \
507 	{ .name = (_name), .key = (void *)(_key), }
508 
lockdep_invariant_state(bool force)509 static inline void lockdep_invariant_state(bool force) {}
lockdep_free_task(struct task_struct * task)510 static inline void lockdep_free_task(struct task_struct *task) {}
511 
512 #ifdef CONFIG_LOCK_STAT
513 
514 extern void lock_contended(struct lockdep_map *lock, unsigned long ip);
515 extern void lock_acquired(struct lockdep_map *lock, unsigned long ip);
516 
517 #define LOCK_CONTENDED(_lock, try, lock)			\
518 do {								\
519 	if (!try(_lock)) {					\
520 		lock_contended(&(_lock)->dep_map, _RET_IP_);	\
521 		lock(_lock);					\
522 	}							\
523 	lock_acquired(&(_lock)->dep_map, _RET_IP_);			\
524 } while (0)
525 
526 #define LOCK_CONTENDED_RETURN(_lock, try, lock)			\
527 ({								\
528 	int ____err = 0;					\
529 	if (!try(_lock)) {					\
530 		lock_contended(&(_lock)->dep_map, _RET_IP_);	\
531 		____err = lock(_lock);				\
532 	}							\
533 	if (!____err)						\
534 		lock_acquired(&(_lock)->dep_map, _RET_IP_);	\
535 	____err;						\
536 })
537 
538 #else /* CONFIG_LOCK_STAT */
539 
540 #define lock_contended(lockdep_map, ip) do {} while (0)
541 #define lock_acquired(lockdep_map, ip) do {} while (0)
542 
543 #define LOCK_CONTENDED(_lock, try, lock) \
544 	lock(_lock)
545 
546 #define LOCK_CONTENDED_RETURN(_lock, try, lock) \
547 	lock(_lock)
548 
549 #endif /* CONFIG_LOCK_STAT */
550 
551 #ifdef CONFIG_LOCKDEP
552 
553 /*
554  * On lockdep we dont want the hand-coded irq-enable of
555  * _raw_*_lock_flags() code, because lockdep assumes
556  * that interrupts are not re-enabled during lock-acquire:
557  */
558 #define LOCK_CONTENDED_FLAGS(_lock, try, lock, lockfl, flags) \
559 	LOCK_CONTENDED((_lock), (try), (lock))
560 
561 #else /* CONFIG_LOCKDEP */
562 
563 #define LOCK_CONTENDED_FLAGS(_lock, try, lock, lockfl, flags) \
564 	lockfl((_lock), (flags))
565 
566 #endif /* CONFIG_LOCKDEP */
567 
568 #ifdef CONFIG_PROVE_LOCKING
569 extern void print_irqtrace_events(struct task_struct *curr);
570 #else
print_irqtrace_events(struct task_struct * curr)571 static inline void print_irqtrace_events(struct task_struct *curr)
572 {
573 }
574 #endif
575 
576 /*
577  * For trivial one-depth nesting of a lock-class, the following
578  * global define can be used. (Subsystems with multiple levels
579  * of nesting should define their own lock-nesting subclasses.)
580  */
581 #define SINGLE_DEPTH_NESTING			1
582 
583 /*
584  * Map the dependency ops to NOP or to real lockdep ops, depending
585  * on the per lock-class debug mode:
586  */
587 
588 #define lock_acquire_exclusive(l, s, t, n, i)		lock_acquire(l, s, t, 0, 1, n, i)
589 #define lock_acquire_shared(l, s, t, n, i)		lock_acquire(l, s, t, 1, 1, n, i)
590 #define lock_acquire_shared_recursive(l, s, t, n, i)	lock_acquire(l, s, t, 2, 1, n, i)
591 
592 #define spin_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
593 #define spin_acquire_nest(l, s, t, n, i)	lock_acquire_exclusive(l, s, t, n, i)
594 #define spin_release(l, n, i)			lock_release(l, n, i)
595 
596 #define rwlock_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
597 #define rwlock_acquire_read(l, s, t, i)		lock_acquire_shared_recursive(l, s, t, NULL, i)
598 #define rwlock_release(l, n, i)			lock_release(l, n, i)
599 
600 #define seqcount_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
601 #define seqcount_acquire_read(l, s, t, i)	lock_acquire_shared_recursive(l, s, t, NULL, i)
602 #define seqcount_release(l, n, i)		lock_release(l, n, i)
603 
604 #define mutex_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
605 #define mutex_acquire_nest(l, s, t, n, i)	lock_acquire_exclusive(l, s, t, n, i)
606 #define mutex_release(l, n, i)			lock_release(l, n, i)
607 
608 #define rwsem_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
609 #define rwsem_acquire_nest(l, s, t, n, i)	lock_acquire_exclusive(l, s, t, n, i)
610 #define rwsem_acquire_read(l, s, t, i)		lock_acquire_shared(l, s, t, NULL, i)
611 #define rwsem_release(l, n, i)			lock_release(l, n, i)
612 
613 #define lock_map_acquire(l)			lock_acquire_exclusive(l, 0, 0, NULL, _THIS_IP_)
614 #define lock_map_acquire_read(l)		lock_acquire_shared_recursive(l, 0, 0, NULL, _THIS_IP_)
615 #define lock_map_acquire_tryread(l)		lock_acquire_shared_recursive(l, 0, 1, NULL, _THIS_IP_)
616 #define lock_map_release(l)			lock_release(l, 1, _THIS_IP_)
617 
618 #ifdef CONFIG_PROVE_LOCKING
619 # define might_lock(lock) 						\
620 do {									\
621 	typecheck(struct lockdep_map *, &(lock)->dep_map);		\
622 	lock_acquire(&(lock)->dep_map, 0, 0, 0, 1, NULL, _THIS_IP_);	\
623 	lock_release(&(lock)->dep_map, 0, _THIS_IP_);			\
624 } while (0)
625 # define might_lock_read(lock) 						\
626 do {									\
627 	typecheck(struct lockdep_map *, &(lock)->dep_map);		\
628 	lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_);	\
629 	lock_release(&(lock)->dep_map, 0, _THIS_IP_);			\
630 } while (0)
631 
632 #define lockdep_assert_irqs_enabled()	do {				\
633 		WARN_ONCE(debug_locks && !current->lockdep_recursion &&	\
634 			  !current->hardirqs_enabled,			\
635 			  "IRQs not enabled as expected\n");		\
636 	} while (0)
637 
638 #define lockdep_assert_irqs_disabled()	do {				\
639 		WARN_ONCE(debug_locks && !current->lockdep_recursion &&	\
640 			  current->hardirqs_enabled,			\
641 			  "IRQs not disabled as expected\n");		\
642 	} while (0)
643 
644 #define lockdep_assert_in_irq() do {					\
645 		WARN_ONCE(debug_locks && !current->lockdep_recursion &&	\
646 			  !current->hardirq_context,			\
647 			  "Not in hardirq as expected\n");		\
648 	} while (0)
649 
650 #else
651 # define might_lock(lock) do { } while (0)
652 # define might_lock_read(lock) do { } while (0)
653 # define lockdep_assert_irqs_enabled() do { } while (0)
654 # define lockdep_assert_irqs_disabled() do { } while (0)
655 # define lockdep_assert_in_irq() do { } while (0)
656 #endif
657 
658 #ifdef CONFIG_LOCKDEP
659 void lockdep_rcu_suspicious(const char *file, const int line, const char *s);
660 #else
661 static inline void
lockdep_rcu_suspicious(const char * file,const int line,const char * s)662 lockdep_rcu_suspicious(const char *file, const int line, const char *s)
663 {
664 }
665 #endif
666 
667 #endif /* __LINUX_LOCKDEP_H */
668