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