1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Runtime locking correctness validator 4 * 5 * Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <[email protected]> 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 #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 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 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 } 201 202 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, (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) 245 246 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); 285 286 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) 300 301 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 #else /* !CONFIG_LOCKDEP */ 348 349 static inline void lockdep_init_task(struct task_struct *task) 350 { 351 } 352 353 static inline void lockdep_off(void) 354 { 355 } 356 357 static inline void lockdep_on(void) 358 { 359 } 360 361 static inline void lockdep_set_selftest_task(struct task_struct *task) 362 { 363 } 364 365 # define lock_acquire(l, s, t, r, c, n, i) do { } while (0) 366 # define lock_release(l, i) do { } while (0) 367 # define lock_downgrade(l, i) do { } while (0) 368 # define lock_set_class(l, n, key, s, i) do { (void)(key); } while (0) 369 # define lock_set_novalidate_class(l, n, i) do { } while (0) 370 # define lock_set_subclass(l, s, i) do { } while (0) 371 # define lockdep_init() do { } while (0) 372 # define lockdep_init_map_type(lock, name, key, sub, inner, outer, type) \ 373 do { (void)(name); (void)(key); } while (0) 374 # define lockdep_init_map_waits(lock, name, key, sub, inner, outer) \ 375 do { (void)(name); (void)(key); } while (0) 376 # define lockdep_init_map_wait(lock, name, key, sub, inner) \ 377 do { (void)(name); (void)(key); } while (0) 378 # define lockdep_init_map(lock, name, key, sub) \ 379 do { (void)(name); (void)(key); } while (0) 380 # define lockdep_set_class(lock, key) do { (void)(key); } while (0) 381 # define lockdep_set_class_and_name(lock, key, name) \ 382 do { (void)(key); (void)(name); } while (0) 383 #define lockdep_set_class_and_subclass(lock, key, sub) \ 384 do { (void)(key); } while (0) 385 #define lockdep_set_subclass(lock, sub) do { } while (0) 386 387 #define lockdep_set_novalidate_class(lock) do { } while (0) 388 389 /* 390 * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP 391 * case since the result is not well defined and the caller should rather 392 * #ifdef the call himself. 393 */ 394 395 # define lockdep_reset() do { debug_locks = 1; } while (0) 396 # define lockdep_free_key_range(start, size) do { } while (0) 397 # define lockdep_sys_exit() do { } while (0) 398 399 static inline void lockdep_register_key(struct lock_class_key *key) 400 { 401 } 402 403 static inline void lockdep_unregister_key(struct lock_class_key *key) 404 { 405 } 406 407 #define lockdep_depth(tsk) (0) 408 409 /* 410 * Dummy forward declarations, allow users to write less ifdef-y code 411 * and depend on dead code elimination. 412 */ 413 extern int lock_is_held(const void *); 414 extern int lockdep_is_held(const void *); 415 #define lockdep_is_held_type(l, r) (1) 416 417 #define lockdep_assert(c) do { } while (0) 418 #define lockdep_assert_once(c) do { } while (0) 419 420 #define lockdep_assert_held(l) do { (void)(l); } while (0) 421 #define lockdep_assert_not_held(l) do { (void)(l); } while (0) 422 #define lockdep_assert_held_write(l) do { (void)(l); } while (0) 423 #define lockdep_assert_held_read(l) do { (void)(l); } while (0) 424 #define lockdep_assert_held_once(l) do { (void)(l); } while (0) 425 #define lockdep_assert_none_held_once() do { } while (0) 426 427 #define lockdep_recursing(tsk) (0) 428 429 #define NIL_COOKIE (struct pin_cookie){ } 430 431 #define lockdep_pin_lock(l) ({ struct pin_cookie cookie = { }; cookie; }) 432 #define lockdep_repin_lock(l, c) do { (void)(l); (void)(c); } while (0) 433 #define lockdep_unpin_lock(l, c) do { (void)(l); (void)(c); } while (0) 434 435 #endif /* !LOCKDEP */ 436 437 enum xhlock_context_t { 438 XHLOCK_HARD, 439 XHLOCK_SOFT, 440 XHLOCK_CTX_NR, 441 }; 442 443 /* 444 * To initialize a lockdep_map statically use this macro. 445 * Note that _name must not be NULL. 446 */ 447 #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \ 448 { .name = (_name), .key = (void *)(_key), } 449 450 static inline void lockdep_invariant_state(bool force) {} 451 static inline void lockdep_free_task(struct task_struct *task) {} 452 453 #ifdef CONFIG_LOCK_STAT 454 455 extern void lock_contended(struct lockdep_map *lock, unsigned long ip); 456 extern void lock_acquired(struct lockdep_map *lock, unsigned long ip); 457 458 #define LOCK_CONTENDED(_lock, try, lock) \ 459 do { \ 460 if (!try(_lock)) { \ 461 lock_contended(&(_lock)->dep_map, _RET_IP_); \ 462 lock(_lock); \ 463 } \ 464 lock_acquired(&(_lock)->dep_map, _RET_IP_); \ 465 } while (0) 466 467 #define LOCK_CONTENDED_RETURN(_lock, try, lock) \ 468 ({ \ 469 int ____err = 0; \ 470 if (!try(_lock)) { \ 471 lock_contended(&(_lock)->dep_map, _RET_IP_); \ 472 ____err = lock(_lock); \ 473 } \ 474 if (!____err) \ 475 lock_acquired(&(_lock)->dep_map, _RET_IP_); \ 476 ____err; \ 477 }) 478 479 #else /* CONFIG_LOCK_STAT */ 480 481 #define lock_contended(lockdep_map, ip) do {} while (0) 482 #define lock_acquired(lockdep_map, ip) do {} while (0) 483 484 #define LOCK_CONTENDED(_lock, try, lock) \ 485 lock(_lock) 486 487 #define LOCK_CONTENDED_RETURN(_lock, try, lock) \ 488 lock(_lock) 489 490 #endif /* CONFIG_LOCK_STAT */ 491 492 #ifdef CONFIG_PROVE_LOCKING 493 extern void print_irqtrace_events(struct task_struct *curr); 494 #else 495 static inline void print_irqtrace_events(struct task_struct *curr) 496 { 497 } 498 #endif 499 500 /* Variable used to make lockdep treat read_lock() as recursive in selftests */ 501 #ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS 502 extern unsigned int force_read_lock_recursive; 503 #else /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */ 504 #define force_read_lock_recursive 0 505 #endif /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */ 506 507 #ifdef CONFIG_LOCKDEP 508 extern bool read_lock_is_recursive(void); 509 #else /* CONFIG_LOCKDEP */ 510 /* If !LOCKDEP, the value is meaningless */ 511 #define read_lock_is_recursive() 0 512 #endif 513 514 /* 515 * For trivial one-depth nesting of a lock-class, the following 516 * global define can be used. (Subsystems with multiple levels 517 * of nesting should define their own lock-nesting subclasses.) 518 */ 519 #define SINGLE_DEPTH_NESTING 1 520 521 /* 522 * Map the dependency ops to NOP or to real lockdep ops, depending 523 * on the per lock-class debug mode: 524 */ 525 526 #define lock_acquire_exclusive(l, s, t, n, i) lock_acquire(l, s, t, 0, 1, n, i) 527 #define lock_acquire_shared(l, s, t, n, i) lock_acquire(l, s, t, 1, 1, n, i) 528 #define lock_acquire_shared_recursive(l, s, t, n, i) lock_acquire(l, s, t, 2, 1, n, i) 529 530 #define spin_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i) 531 #define spin_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i) 532 #define spin_release(l, i) lock_release(l, i) 533 534 #define rwlock_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i) 535 #define rwlock_acquire_read(l, s, t, i) \ 536 do { \ 537 if (read_lock_is_recursive()) \ 538 lock_acquire_shared_recursive(l, s, t, NULL, i); \ 539 else \ 540 lock_acquire_shared(l, s, t, NULL, i); \ 541 } while (0) 542 543 #define rwlock_release(l, i) lock_release(l, i) 544 545 #define seqcount_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i) 546 #define seqcount_acquire_read(l, s, t, i) lock_acquire_shared_recursive(l, s, t, NULL, i) 547 #define seqcount_release(l, i) lock_release(l, i) 548 549 #define mutex_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i) 550 #define mutex_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i) 551 #define mutex_release(l, i) lock_release(l, i) 552 553 #define rwsem_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i) 554 #define rwsem_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i) 555 #define rwsem_acquire_read(l, s, t, i) lock_acquire_shared(l, s, t, NULL, i) 556 #define rwsem_release(l, i) lock_release(l, i) 557 558 #define lock_map_acquire(l) lock_acquire_exclusive(l, 0, 0, NULL, _THIS_IP_) 559 #define lock_map_acquire_read(l) lock_acquire_shared_recursive(l, 0, 0, NULL, _THIS_IP_) 560 #define lock_map_acquire_tryread(l) lock_acquire_shared_recursive(l, 0, 1, NULL, _THIS_IP_) 561 #define lock_map_release(l) lock_release(l, _THIS_IP_) 562 #define lock_map_sync(l) lock_sync(l, 0, 0, 1, NULL, _THIS_IP_) 563 564 #ifdef CONFIG_PROVE_LOCKING 565 # define might_lock(lock) \ 566 do { \ 567 typecheck(struct lockdep_map *, &(lock)->dep_map); \ 568 lock_acquire(&(lock)->dep_map, 0, 0, 0, 1, NULL, _THIS_IP_); \ 569 lock_release(&(lock)->dep_map, _THIS_IP_); \ 570 } while (0) 571 # define might_lock_read(lock) \ 572 do { \ 573 typecheck(struct lockdep_map *, &(lock)->dep_map); \ 574 lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_); \ 575 lock_release(&(lock)->dep_map, _THIS_IP_); \ 576 } while (0) 577 # define might_lock_nested(lock, subclass) \ 578 do { \ 579 typecheck(struct lockdep_map *, &(lock)->dep_map); \ 580 lock_acquire(&(lock)->dep_map, subclass, 0, 1, 1, NULL, \ 581 _THIS_IP_); \ 582 lock_release(&(lock)->dep_map, _THIS_IP_); \ 583 } while (0) 584 585 DECLARE_PER_CPU(int, hardirqs_enabled); 586 DECLARE_PER_CPU(int, hardirq_context); 587 DECLARE_PER_CPU(unsigned int, lockdep_recursion); 588 589 #define __lockdep_enabled (debug_locks && !this_cpu_read(lockdep_recursion)) 590 591 #define lockdep_assert_irqs_enabled() \ 592 do { \ 593 WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirqs_enabled)); \ 594 } while (0) 595 596 #define lockdep_assert_irqs_disabled() \ 597 do { \ 598 WARN_ON_ONCE(__lockdep_enabled && this_cpu_read(hardirqs_enabled)); \ 599 } while (0) 600 601 #define lockdep_assert_in_irq() \ 602 do { \ 603 WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirq_context)); \ 604 } while (0) 605 606 #define lockdep_assert_preemption_enabled() \ 607 do { \ 608 WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \ 609 __lockdep_enabled && \ 610 (preempt_count() != 0 || \ 611 !this_cpu_read(hardirqs_enabled))); \ 612 } while (0) 613 614 #define lockdep_assert_preemption_disabled() \ 615 do { \ 616 WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \ 617 __lockdep_enabled && \ 618 (preempt_count() == 0 && \ 619 this_cpu_read(hardirqs_enabled))); \ 620 } while (0) 621 622 /* 623 * Acceptable for protecting per-CPU resources accessed from BH. 624 * Much like in_softirq() - semantics are ambiguous, use carefully. 625 */ 626 #define lockdep_assert_in_softirq() \ 627 do { \ 628 WARN_ON_ONCE(__lockdep_enabled && \ 629 (!in_softirq() || in_irq() || in_nmi())); \ 630 } while (0) 631 632 #else 633 # define might_lock(lock) do { } while (0) 634 # define might_lock_read(lock) do { } while (0) 635 # define might_lock_nested(lock, subclass) do { } while (0) 636 637 # define lockdep_assert_irqs_enabled() do { } while (0) 638 # define lockdep_assert_irqs_disabled() do { } while (0) 639 # define lockdep_assert_in_irq() do { } while (0) 640 641 # define lockdep_assert_preemption_enabled() do { } while (0) 642 # define lockdep_assert_preemption_disabled() do { } while (0) 643 # define lockdep_assert_in_softirq() do { } while (0) 644 #endif 645 646 #ifdef CONFIG_PROVE_RAW_LOCK_NESTING 647 648 # define lockdep_assert_RT_in_threaded_ctx() do { \ 649 WARN_ONCE(debug_locks && !current->lockdep_recursion && \ 650 lockdep_hardirq_context() && \ 651 !(current->hardirq_threaded || current->irq_config), \ 652 "Not in threaded context on PREEMPT_RT as expected\n"); \ 653 } while (0) 654 655 #else 656 657 # define lockdep_assert_RT_in_threaded_ctx() do { } while (0) 658 659 #endif 660 661 #ifdef CONFIG_LOCKDEP 662 void lockdep_rcu_suspicious(const char *file, const int line, const char *s); 663 #else 664 static inline void 665 lockdep_rcu_suspicious(const char *file, const int line, const char *s) 666 { 667 } 668 #endif 669 670 #endif /* __LINUX_LOCKDEP_H */ 671