include/linux/lockdep.h

   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
  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 /*
  86  * Initialization, self-test and debugging-output methods:
  87  */
  88 extern void lockdep_init(void);
  89 extern void lockdep_reset(void);
  90 extern void lockdep_reset_lock(struct lockdep_map *lock);
  91 extern void lockdep_free_key_range(void *start, unsigned long size);
  92 extern asmlinkage void lockdep_sys_exit(void);
  93 extern void lockdep_set_selftest_task(struct task_struct *task);
  94
  95 extern void lockdep_init_task(struct task_struct *task);
  96
  97 /*
  98  * Split the recursion counter in two to readily detect 'off' vs recursion.
  99  */
 100 #define LOCKDEP_RECURSION_BITS  16
 101 #define LOCKDEP_OFF             (1U << LOCKDEP_RECURSION_BITS)
 102 #define LOCKDEP_RECURSION_MASK  (LOCKDEP_OFF - 1)
 103
 104 /*
 105  * lockdep_{off,on}() are macros to avoid tracing and kprobes; not inlines due
 106  * to header dependencies.
 107  */
 108
 109 #define lockdep_off()                                   \
 110 do {                                                    \
 111         current->lockdep_recursion += LOCKDEP_OFF;      \
 112 } while (0)
 113
 114 #define lockdep_on()                                    \
 115 do {                                                    \
 116         current->lockdep_recursion -= LOCKDEP_OFF;      \
 117 } while (0)
 118
 119 extern void lockdep_register_key(struct lock_class_key *key);
 120 extern void lockdep_unregister_key(struct lock_class_key *key);
 121
 122 /*
 123  * These methods are used by specific locking variants (spinlocks,
 124  * rwlocks, mutexes and rwsems) to pass init/acquire/release events
 125  * to lockdep:
 126  */
 127
 128 extern void lockdep_init_map_type(struct lockdep_map *lock, const char *name,
 129         struct lock_class_key *key, int subclass, u8 inner, u8 outer, u8 lock_type);
 130
 131 static inline void
 132 lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
 133                        struct lock_class_key *key, int subclass, u8 inner, u8 outer)
 134 {
 135         lockdep_init_map_type(lock, name, key, subclass, inner, outer, LD_LOCK_NORMAL);
 136 }
 137
 138 static inline void
 139 lockdep_init_map_wait(struct lockdep_map *lock, const char *name,
 140                       struct lock_class_key *key, int subclass, u8 inner)
 141 {
 142         lockdep_init_map_waits(lock, name, key, subclass, inner, LD_WAIT_INV);
 143 }
 144
 145 static inline void lockdep_init_map(struct lockdep_map *lock, const char *name,
 146                              struct lock_class_key *key, int subclass)
 147 {
 148         lockdep_init_map_wait(lock, name, key, subclass, LD_WAIT_INV);
 149 }
 150
 151 /*
 152  * Reinitialize a lock key - for cases where there is special locking or
 153  * special initialization of locks so that the validator gets the scope
 154  * of dependencies wrong: they are either too broad (they need a class-split)
 155  * or they are too narrow (they suffer from a false class-split):
 156  */
 157 #define lockdep_set_class(lock, key)                            \
 158         lockdep_init_map_type(&(lock)->dep_map, #key, key, 0,   \
 159                               (lock)->dep_map.wait_type_inner,  \
 160                               (lock)->dep_map.wait_type_outer,  \
 161                               (lock)->dep_map.lock_type)
 162
 163 #define lockdep_set_class_and_name(lock, key, name)             \
 164         lockdep_init_map_type(&(lock)->dep_map, name, key, 0,   \
 165                               (lock)->dep_map.wait_type_inner,  \
 166                               (lock)->dep_map.wait_type_outer,  \
 167                               (lock)->dep_map.lock_type)
 168
 169 #define lockdep_set_class_and_subclass(lock, key, sub)          \
 170         lockdep_init_map_type(&(lock)->dep_map, #key, key, sub, \
 171                               (lock)->dep_map.wait_type_inner,  \
 172                               (lock)->dep_map.wait_type_outer,  \
 173                               (lock)->dep_map.lock_type)
 174
 175 #define lockdep_set_subclass(lock, sub)                                 \
 176         lockdep_init_map_type(&(lock)->dep_map, #lock, (lock)->dep_map.key, sub,\
 177                               (lock)->dep_map.wait_type_inner,          \
 178                               (lock)->dep_map.wait_type_outer,          \
 179                               (lock)->dep_map.lock_type)
 180
 181 #define lockdep_set_novalidate_class(lock) \
 182         lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock)
 183
 184 /*
 185  * Compare locking classes
 186  */
 187 #define lockdep_match_class(lock, key) lockdep_match_key(&(lock)->dep_map, key)
 188
 189 static inline int lockdep_match_key(struct lockdep_map *lock,
 190                                     struct lock_class_key *key)
 191 {
 192         return lock->key == key;
 193 }
 194
 195 /*
 196  * Acquire a lock.
 197  *
 198  * Values for "read":
 199  *
 200  *   0: exclusive (write) acquire
 201  *   1: read-acquire (no recursion allowed)
 202  *   2: read-acquire with same-instance recursion allowed
 203  *
 204  * Values for check:
 205  *
 206  *   0: simple checks (freeing, held-at-exit-time, etc.)
 207  *   1: full validation
 208  */
 209 extern void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 210                          int trylock, int read, int check,
 211                          struct lockdep_map *nest_lock, unsigned long ip);
 212
 213 extern void lock_release(struct lockdep_map *lock, unsigned long ip);
 214
 215 extern void lock_sync(struct lockdep_map *lock, unsigned int subclass,
 216                       int read, int check, struct lockdep_map *nest_lock,
 217                       unsigned long ip);
 218
 219 /* lock_is_held_type() returns */
 220 #define LOCK_STATE_UNKNOWN      -1
 221 #define LOCK_STATE_NOT_HELD     0
 222 #define LOCK_STATE_HELD         1
 223
 224 /*
 225  * Same "read" as for lock_acquire(), except -1 means any.
 226  */
 227 extern int lock_is_held_type(const struct lockdep_map *lock, int read);
 228
 229 static inline int lock_is_held(const struct lockdep_map *lock)
 230 {
 231         return lock_is_held_type(lock, -1);
 232 }
 233
 234 #define lockdep_is_held(lock)           lock_is_held(&(lock)->dep_map)
 235 #define lockdep_is_held_type(lock, r)   lock_is_held_type(&(lock)->dep_map, (r))
 236
 237 extern void lock_set_class(struct lockdep_map *lock, const char *name,
 238                            struct lock_class_key *key, unsigned int subclass,
 239                            unsigned long ip);
 240
 241 #define lock_set_novalidate_class(l, n, i) \
 242         lock_set_class(l, n, &__lockdep_no_validate__, 0, i)
 243
 244 static inline void lock_set_subclass(struct lockdep_map *lock,
 245                 unsigned int subclass, unsigned long ip)
 246 {
 247         lock_set_class(lock, lock->name, lock->key, subclass, ip);
 248 }
 249
 250 extern void lock_downgrade(struct lockdep_map *lock, unsigned long ip);
 251
 252 #define NIL_COOKIE (struct pin_cookie){ .val = 0U, }
 253
 254 extern struct pin_cookie lock_pin_lock(struct lockdep_map *lock);
 255 extern void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie);
 256 extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);
 257
 258 #define lockdep_depth(tsk)      (debug_locks ? (tsk)->lockdep_depth : 0)
 259
 260 #define lockdep_assert(cond)            \
 261         do { WARN_ON(debug_locks && !(cond)); } while (0)
 262
 263 #define lockdep_assert_once(cond)       \
 264         do { WARN_ON_ONCE(debug_locks && !(cond)); } while (0)
 265
 266 #define lockdep_assert_held(l)          \
 267         lockdep_assert(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
 268
 269 #define lockdep_assert_not_held(l)      \
 270         lockdep_assert(lockdep_is_held(l) != LOCK_STATE_HELD)
 271
 272 #define lockdep_assert_held_write(l)    \
 273         lockdep_assert(lockdep_is_held_type(l, 0))
 274
 275 #define lockdep_assert_held_read(l)     \
 276         lockdep_assert(lockdep_is_held_type(l, 1))
 277
 278 #define lockdep_assert_held_once(l)             \
 279         lockdep_assert_once(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
 280
 281 #define lockdep_assert_none_held_once()         \
 282         lockdep_assert_once(!current->lockdep_depth)
 283
 284 #define lockdep_recursing(tsk)  ((tsk)->lockdep_recursion)
 285
 286 #define lockdep_pin_lock(l)     lock_pin_lock(&(l)->dep_map)
 287 #define lockdep_repin_lock(l,c) lock_repin_lock(&(l)->dep_map, (c))
 288 #define lockdep_unpin_lock(l,c) lock_unpin_lock(&(l)->dep_map, (c))
 289
 290 /*
 291  * Must use lock_map_aquire_try() with override maps to avoid
 292  * lockdep thinking they participate in the block chain.
 293  */
 294 #define DEFINE_WAIT_OVERRIDE_MAP(_name, _wait_type)     \
 295         struct lockdep_map _name = {                    \
 296                 .name = #_name "-wait-type-override",   \
 297                 .wait_type_inner = _wait_type,          \
 298                 .lock_type = LD_LOCK_WAIT_OVERRIDE, }
 299
 300 #else /* !CONFIG_LOCKDEP */
 301
 302 static inline void lockdep_init_task(struct task_struct *task)
 303 {
 304 }
 305
 306 static inline void lockdep_off(void)
 307 {
 308 }
 309
 310 static inline void lockdep_on(void)
 311 {
 312 }
 313
 314 static inline void lockdep_set_selftest_task(struct task_struct *task)
 315 {
 316 }
 317
 318 # define lock_acquire(l, s, t, r, c, n, i)      do { } while (0)
 319 # define lock_release(l, i)                     do { } while (0)
 320 # define lock_downgrade(l, i)                   do { } while (0)
 321 # define lock_set_class(l, n, key, s, i)        do { (void)(key); } while (0)
 322 # define lock_set_novalidate_class(l, n, i)     do { } while (0)
 323 # define lock_set_subclass(l, s, i)             do { } while (0)
 324 # define lockdep_init()                         do { } while (0)
 325 # define lockdep_init_map_type(lock, name, key, sub, inner, outer, type) \
 326                 do { (void)(name); (void)(key); } while (0)
 327 # define lockdep_init_map_waits(lock, name, key, sub, inner, outer) \
 328                 do { (void)(name); (void)(key); } while (0)
 329 # define lockdep_init_map_wait(lock, name, key, sub, inner) \
 330                 do { (void)(name); (void)(key); } while (0)
 331 # define lockdep_init_map(lock, name, key, sub) \
 332                 do { (void)(name); (void)(key); } while (0)
 333 # define lockdep_set_class(lock, key)           do { (void)(key); } while (0)
 334 # define lockdep_set_class_and_name(lock, key, name) \
 335                 do { (void)(key); (void)(name); } while (0)
 336 #define lockdep_set_class_and_subclass(lock, key, sub) \
 337                 do { (void)(key); } while (0)
 338 #define lockdep_set_subclass(lock, sub)         do { } while (0)
 339
 340 #define lockdep_set_novalidate_class(lock) do { } while (0)
 341
 342 /*
 343  * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP
 344  * case since the result is not well defined and the caller should rather
 345  * #ifdef the call himself.
 346  */
 347
 348 # define lockdep_reset()                do { debug_locks = 1; } while (0)
 349 # define lockdep_free_key_range(start, size)    do { } while (0)
 350 # define lockdep_sys_exit()                     do { } while (0)
 351
 352 static inline void lockdep_register_key(struct lock_class_key *key)
 353 {
 354 }
 355
 356 static inline void lockdep_unregister_key(struct lock_class_key *key)
 357 {
 358 }
 359
 360 #define lockdep_depth(tsk)      (0)
 361
 362 /*
 363  * Dummy forward declarations, allow users to write less ifdef-y code
 364  * and depend on dead code elimination.
 365  */
 366 extern int lock_is_held(const void *);
 367 extern int lockdep_is_held(const void *);
 368 #define lockdep_is_held_type(l, r)              (1)
 369
 370 #define lockdep_assert(c)                       do { } while (0)
 371 #define lockdep_assert_once(c)                  do { } while (0)
 372
 373 #define lockdep_assert_held(l)                  do { (void)(l); } while (0)
 374 #define lockdep_assert_not_held(l)              do { (void)(l); } while (0)
 375 #define lockdep_assert_held_write(l)            do { (void)(l); } while (0)
 376 #define lockdep_assert_held_read(l)             do { (void)(l); } while (0)
 377 #define lockdep_assert_held_once(l)             do { (void)(l); } while (0)
 378 #define lockdep_assert_none_held_once() do { } while (0)
 379
 380 #define lockdep_recursing(tsk)                  (0)
 381
 382 #define NIL_COOKIE (struct pin_cookie){ }
 383
 384 #define lockdep_pin_lock(l)                     ({ struct pin_cookie cookie = { }; cookie; })
 385 #define lockdep_repin_lock(l, c)                do { (void)(l); (void)(c); } while (0)
 386 #define lockdep_unpin_lock(l, c)                do { (void)(l); (void)(c); } while (0)
 387
 388 #define DEFINE_WAIT_OVERRIDE_MAP(_name, _wait_type)     \
 389         struct lockdep_map __maybe_unused _name = {}
 390
 391 #endif /* !LOCKDEP */
 392
 393 #ifdef CONFIG_PROVE_LOCKING
 394 void lockdep_set_lock_cmp_fn(struct lockdep_map *, lock_cmp_fn, lock_print_fn);
 395
 396 #define lock_set_cmp_fn(lock, ...)      lockdep_set_lock_cmp_fn(&(lock)->dep_map, __VA_ARGS__)
 397 #else
 398 #define lock_set_cmp_fn(lock, ...)      do { } while (0)
 399 #endif
 400
 401 enum xhlock_context_t {
 402         XHLOCK_HARD,
 403         XHLOCK_SOFT,
 404         XHLOCK_CTX_NR,
 405 };
 406
 407 /*
 408  * To initialize a lockdep_map statically use this macro.
 409  * Note that _name must not be NULL.
 410  */
 411 #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \
 412         { .name = (_name), .key = (void *)(_key), }
 413
 414 static inline void lockdep_invariant_state(bool force) {}
 415 static inline void lockdep_free_task(struct task_struct *task) {}
 416
 417 #ifdef CONFIG_LOCK_STAT
 418
 419 extern void lock_contended(struct lockdep_map *lock, unsigned long ip);
 420 extern void lock_acquired(struct lockdep_map *lock, unsigned long ip);
 421
 422 #define LOCK_CONTENDED(_lock, try, lock)                        \
 423 do {                                                            \
 424         if (!try(_lock)) {                                      \
 425                 lock_contended(&(_lock)->dep_map, _RET_IP_);    \
 426                 lock(_lock);                                    \
 427         }                                                       \
 428         lock_acquired(&(_lock)->dep_map, _RET_IP_);                     \
 429 } while (0)
 430
 431 #define LOCK_CONTENDED_RETURN(_lock, try, lock)                 \
 432 ({                                                              \
 433         int ____err = 0;                                        \
 434         if (!try(_lock)) {                                      \
 435                 lock_contended(&(_lock)->dep_map, _RET_IP_);    \
 436                 ____err = lock(_lock);                          \
 437         }                                                       \
 438         if (!____err)                                           \
 439                 lock_acquired(&(_lock)->dep_map, _RET_IP_);     \
 440         ____err;                                                \
 441 })
 442
 443 #else /* CONFIG_LOCK_STAT */
 444
 445 #define lock_contended(lockdep_map, ip) do {} while (0)
 446 #define lock_acquired(lockdep_map, ip) do {} while (0)
 447
 448 #define LOCK_CONTENDED(_lock, try, lock) \
 449         lock(_lock)
 450
 451 #define LOCK_CONTENDED_RETURN(_lock, try, lock) \
 452         lock(_lock)
 453
 454 #endif /* CONFIG_LOCK_STAT */
 455
 456 #ifdef CONFIG_PROVE_LOCKING
 457 extern void print_irqtrace_events(struct task_struct *curr);
 458 #else
 459 static inline void print_irqtrace_events(struct task_struct *curr)
 460 {
 461 }
 462 #endif
 463
 464 /* Variable used to make lockdep treat read_lock() as recursive in selftests */
 465 #ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS
 466 extern unsigned int force_read_lock_recursive;
 467 #else /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
 468 #define force_read_lock_recursive 0
 469 #endif /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
 470
 471 #ifdef CONFIG_LOCKDEP
 472 extern bool read_lock_is_recursive(void);
 473 #else /* CONFIG_LOCKDEP */
 474 /* If !LOCKDEP, the value is meaningless */
 475 #define read_lock_is_recursive() 0
 476 #endif
 477
 478 /*
 479  * For trivial one-depth nesting of a lock-class, the following
 480  * global define can be used. (Subsystems with multiple levels
 481  * of nesting should define their own lock-nesting subclasses.)
 482  */
 483 #define SINGLE_DEPTH_NESTING                    1
 484
 485 /*
 486  * Map the dependency ops to NOP or to real lockdep ops, depending
 487  * on the per lock-class debug mode:
 488  */
 489
 490 #define lock_acquire_exclusive(l, s, t, n, i)           lock_acquire(l, s, t, 0, 1, n, i)
 491 #define lock_acquire_shared(l, s, t, n, i)              lock_acquire(l, s, t, 1, 1, n, i)
 492 #define lock_acquire_shared_recursive(l, s, t, n, i)    lock_acquire(l, s, t, 2, 1, n, i)
 493
 494 #define spin_acquire(l, s, t, i)                lock_acquire_exclusive(l, s, t, NULL, i)
 495 #define spin_acquire_nest(l, s, t, n, i)        lock_acquire_exclusive(l, s, t, n, i)
 496 #define spin_release(l, i)                      lock_release(l, i)
 497
 498 #define rwlock_acquire(l, s, t, i)              lock_acquire_exclusive(l, s, t, NULL, i)
 499 #define rwlock_acquire_read(l, s, t, i)                                 \
 500 do {                                                                    \
 501         if (read_lock_is_recursive())                                   \
 502                 lock_acquire_shared_recursive(l, s, t, NULL, i);        \
 503         else                                                            \
 504                 lock_acquire_shared(l, s, t, NULL, i);                  \
 505 } while (0)
 506
 507 #define rwlock_release(l, i)                    lock_release(l, i)
 508
 509 #define seqcount_acquire(l, s, t, i)            lock_acquire_exclusive(l, s, t, NULL, i)
 510 #define seqcount_acquire_read(l, s, t, i)       lock_acquire_shared_recursive(l, s, t, NULL, i)
 511 #define seqcount_release(l, i)                  lock_release(l, i)
 512
 513 #define mutex_acquire(l, s, t, i)               lock_acquire_exclusive(l, s, t, NULL, i)
 514 #define mutex_acquire_nest(l, s, t, n, i)       lock_acquire_exclusive(l, s, t, n, i)
 515 #define mutex_release(l, i)                     lock_release(l, i)
 516
 517 #define rwsem_acquire(l, s, t, i)               lock_acquire_exclusive(l, s, t, NULL, i)
 518 #define rwsem_acquire_nest(l, s, t, n, i)       lock_acquire_exclusive(l, s, t, n, i)
 519 #define rwsem_acquire_read(l, s, t, i)          lock_acquire_shared(l, s, t, NULL, i)
 520 #define rwsem_release(l, i)                     lock_release(l, i)
 521
 522 #define lock_map_acquire(l)                     lock_acquire_exclusive(l, 0, 0, NULL, _THIS_IP_)
 523 #define lock_map_acquire_try(l)                 lock_acquire_exclusive(l, 0, 1, NULL, _THIS_IP_)
 524 #define lock_map_acquire_read(l)                lock_acquire_shared_recursive(l, 0, 0, NULL, _THIS_IP_)
 525 #define lock_map_acquire_tryread(l)             lock_acquire_shared_recursive(l, 0, 1, NULL, _THIS_IP_)
 526 #define lock_map_release(l)                     lock_release(l, _THIS_IP_)
 527 #define lock_map_sync(l)                        lock_sync(l, 0, 0, 1, NULL, _THIS_IP_)
 528
 529 #ifdef CONFIG_PROVE_LOCKING
 530 # define might_lock(lock)                                               \
 531 do {                                                                    \
 532         typecheck(struct lockdep_map *, &(lock)->dep_map);              \
 533         lock_acquire(&(lock)->dep_map, 0, 0, 0, 1, NULL, _THIS_IP_);    \
 534         lock_release(&(lock)->dep_map, _THIS_IP_);                      \
 535 } while (0)
 536 # define might_lock_read(lock)                                          \
 537 do {                                                                    \
 538         typecheck(struct lockdep_map *, &(lock)->dep_map);              \
 539         lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_);    \
 540         lock_release(&(lock)->dep_map, _THIS_IP_);                      \
 541 } while (0)
 542 # define might_lock_nested(lock, subclass)                              \
 543 do {                                                                    \
 544         typecheck(struct lockdep_map *, &(lock)->dep_map);              \
 545         lock_acquire(&(lock)->dep_map, subclass, 0, 1, 1, NULL,         \
 546                      _THIS_IP_);                                        \
 547         lock_release(&(lock)->dep_map, _THIS_IP_);                      \
 548 } while (0)
 549
 550 DECLARE_PER_CPU(int, hardirqs_enabled);
 551 DECLARE_PER_CPU(int, hardirq_context);
 552 DECLARE_PER_CPU(unsigned int, lockdep_recursion);
 553
 554 #define __lockdep_enabled       (debug_locks && !this_cpu_read(lockdep_recursion))
 555
 556 #define lockdep_assert_irqs_enabled()                                   \
 557 do {                                                                    \
 558         WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirqs_enabled)); \
 559 } while (0)
 560
 561 #define lockdep_assert_irqs_disabled()                                  \
 562 do {                                                                    \
 563         WARN_ON_ONCE(__lockdep_enabled && this_cpu_read(hardirqs_enabled)); \
 564 } while (0)
 565
 566 #define lockdep_assert_in_irq()                                         \
 567 do {                                                                    \
 568         WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirq_context)); \
 569 } while (0)
 570
 571 #define lockdep_assert_no_hardirq()                                     \
 572 do {                                                                    \
 573         WARN_ON_ONCE(__lockdep_enabled && (this_cpu_read(hardirq_context) || \
 574                                            !this_cpu_read(hardirqs_enabled))); \
 575 } while (0)
 576
 577 #define lockdep_assert_preemption_enabled()                             \
 578 do {                                                                    \
 579         WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT)   &&              \
 580                      __lockdep_enabled                  &&              \
 581                      (preempt_count() != 0              ||              \
 582                       !this_cpu_read(hardirqs_enabled)));               \
 583 } while (0)
 584
 585 #define lockdep_assert_preemption_disabled()                            \
 586 do {                                                                    \
 587         WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT)   &&              \
 588                      __lockdep_enabled                  &&              \
 589                      (preempt_count() == 0              &&              \
 590                       this_cpu_read(hardirqs_enabled)));                \
 591 } while (0)
 592
 593 /*
 594  * Acceptable for protecting per-CPU resources accessed from BH.
 595  * Much like in_softirq() - semantics are ambiguous, use carefully.
 596  */
 597 #define lockdep_assert_in_softirq()                                     \
 598 do {                                                                    \
 599         WARN_ON_ONCE(__lockdep_enabled                  &&              \
 600                      (!in_softirq() || in_irq() || in_nmi()));          \
 601 } while (0)
 602
 603 #else
 604 # define might_lock(lock) do { } while (0)
 605 # define might_lock_read(lock) do { } while (0)
 606 # define might_lock_nested(lock, subclass) do { } while (0)
 607
 608 # define lockdep_assert_irqs_enabled() do { } while (0)
 609 # define lockdep_assert_irqs_disabled() do { } while (0)
 610 # define lockdep_assert_in_irq() do { } while (0)
 611 # define lockdep_assert_no_hardirq() do { } while (0)
 612
 613 # define lockdep_assert_preemption_enabled() do { } while (0)
 614 # define lockdep_assert_preemption_disabled() do { } while (0)
 615 # define lockdep_assert_in_softirq() do { } while (0)
 616 #endif
 617
 618 #ifdef CONFIG_PROVE_RAW_LOCK_NESTING
 619
 620 # define lockdep_assert_RT_in_threaded_ctx() do {                       \
 621                 WARN_ONCE(debug_locks && !current->lockdep_recursion && \
 622                           lockdep_hardirq_context() &&                  \
 623                           !(current->hardirq_threaded || current->irq_config),  \
 624                           "Not in threaded context on PREEMPT_RT as expected\n");       \
 625 } while (0)
 626
 627 #else
 628
 629 # define lockdep_assert_RT_in_threaded_ctx() do { } while (0)
 630
 631 #endif
 632
 633 #ifdef CONFIG_LOCKDEP
 634 void lockdep_rcu_suspicious(const char *file, const int line, const char *s);
 635 #else
 636 static inline void
 637 lockdep_rcu_suspicious(const char *file, const int line, const char *s)
 638 {
 639 }
 640 #endif
 641
 642 #endif /* __LINUX_LOCKDEP_H */