include/linux/lockdep.h

   1 /*
   2  * Runtime locking correctness validator
   3  *
   4  *  Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
   5  *  Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
   6  *
   7  * see Documentation/locking/lockdep-design.txt for more details.
   8  */
   9 #ifndef __LINUX_LOCKDEP_H
  10 #define __LINUX_LOCKDEP_H
  11
  12 struct task_struct;
  13 struct lockdep_map;
  14
  15 /* for sysctl */
  16 extern int prove_locking;
  17 extern int lock_stat;
  18
  19 #define MAX_LOCKDEP_SUBCLASSES          8UL
  20
  21 #include <linux/types.h>
  22
  23 #ifdef CONFIG_LOCKDEP
  24
  25 #include <linux/linkage.h>
  26 #include <linux/list.h>
  27 #include <linux/debug_locks.h>
  28 #include <linux/stacktrace.h>
  29
  30 /*
  31  * We'd rather not expose kernel/lockdep_states.h this wide, but we do need
  32  * the total number of states... :-(
  33  */
  34 #define XXX_LOCK_USAGE_STATES           (1+2*4)
  35
  36 /*
  37  * NR_LOCKDEP_CACHING_CLASSES ... Number of classes
  38  * cached in the instance of lockdep_map
  39  *
  40  * Currently main class (subclass == 0) and signle depth subclass
  41  * are cached in lockdep_map. This optimization is mainly targeting
  42  * on rq->lock. double_rq_lock() acquires this highly competitive with
  43  * single depth.
  44  */
  45 #define NR_LOCKDEP_CACHING_CLASSES      2
  46
  47 /*
  48  * Lock-classes are keyed via unique addresses, by embedding the
  49  * lockclass-key into the kernel (or module) .data section. (For
  50  * static locks we use the lock address itself as the key.)
  51  */
  52 struct lockdep_subclass_key {
  53         char __one_byte;
  54 } __attribute__ ((__packed__));
  55
  56 struct lock_class_key {
  57         struct lockdep_subclass_key     subkeys[MAX_LOCKDEP_SUBCLASSES];
  58 };
  59
  60 extern struct lock_class_key __lockdep_no_validate__;
  61
  62 #define LOCKSTAT_POINTS         4
  63
  64 /*
  65  * The lock-class itself:
  66  */
  67 struct lock_class {
  68         /*
  69          * class-hash:
  70          */
  71         struct hlist_node               hash_entry;
  72
  73         /*
  74          * global list of all lock-classes:
  75          */
  76         struct list_head                lock_entry;
  77
  78         struct lockdep_subclass_key     *key;
  79         unsigned int                    subclass;
  80         unsigned int                    dep_gen_id;
  81
  82         /*
  83          * IRQ/softirq usage tracking bits:
  84          */
  85         unsigned long                   usage_mask;
  86         struct stack_trace              usage_traces[XXX_LOCK_USAGE_STATES];
  87
  88         /*
  89          * These fields represent a directed graph of lock dependencies,
  90          * to every node we attach a list of "forward" and a list of
  91          * "backward" graph nodes.
  92          */
  93         struct list_head                locks_after, locks_before;
  94
  95         /*
  96          * Generation counter, when doing certain classes of graph walking,
  97          * to ensure that we check one node only once:
  98          */
  99         unsigned int                    version;
 100
 101         /*
 102          * Statistics counter:
 103          */
 104         unsigned long                   ops;
 105
 106         const char                      *name;
 107         int                             name_version;
 108
 109 #ifdef CONFIG_LOCK_STAT
 110         unsigned long                   contention_point[LOCKSTAT_POINTS];
 111         unsigned long                   contending_point[LOCKSTAT_POINTS];
 112 #endif
 113 };
 114
 115 #ifdef CONFIG_LOCK_STAT
 116 struct lock_time {
 117         s64                             min;
 118         s64                             max;
 119         s64                             total;
 120         unsigned long                   nr;
 121 };
 122
 123 enum bounce_type {
 124         bounce_acquired_write,
 125         bounce_acquired_read,
 126         bounce_contended_write,
 127         bounce_contended_read,
 128         nr_bounce_types,
 129
 130         bounce_acquired = bounce_acquired_write,
 131         bounce_contended = bounce_contended_write,
 132 };
 133
 134 struct lock_class_stats {
 135         unsigned long                   contention_point[LOCKSTAT_POINTS];
 136         unsigned long                   contending_point[LOCKSTAT_POINTS];
 137         struct lock_time                read_waittime;
 138         struct lock_time                write_waittime;
 139         struct lock_time                read_holdtime;
 140         struct lock_time                write_holdtime;
 141         unsigned long                   bounces[nr_bounce_types];
 142 };
 143
 144 struct lock_class_stats lock_stats(struct lock_class *class);
 145 void clear_lock_stats(struct lock_class *class);
 146 #endif
 147
 148 /*
 149  * Map the lock object (the lock instance) to the lock-class object.
 150  * This is embedded into specific lock instances:
 151  */
 152 struct lockdep_map {
 153         struct lock_class_key           *key;
 154         struct lock_class               *class_cache[NR_LOCKDEP_CACHING_CLASSES];
 155         const char                      *name;
 156 #ifdef CONFIG_LOCK_STAT
 157         int                             cpu;
 158         unsigned long                   ip;
 159 #endif
 160 #ifdef CONFIG_LOCKDEP_CROSSRELEASE
 161         /*
 162          * Whether it's a crosslock.
 163          */
 164         int                             cross;
 165 #endif
 166 };
 167
 168 static inline void lockdep_copy_map(struct lockdep_map *to,
 169                                     struct lockdep_map *from)
 170 {
 171         int i;
 172
 173         *to = *from;
 174         /*
 175          * Since the class cache can be modified concurrently we could observe
 176          * half pointers (64bit arch using 32bit copy insns). Therefore clear
 177          * the caches and take the performance hit.
 178          *
 179          * XXX it doesn't work well with lockdep_set_class_and_subclass(), since
 180          *     that relies on cache abuse.
 181          */
 182         for (i = 0; i < NR_LOCKDEP_CACHING_CLASSES; i++)
 183                 to->class_cache[i] = NULL;
 184 }
 185
 186 /*
 187  * Every lock has a list of other locks that were taken after it.
 188  * We only grow the list, never remove from it:
 189  */
 190 struct lock_list {
 191         struct list_head                entry;
 192         struct lock_class               *class;
 193         struct stack_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  * We record lock dependency chains, so that we can cache them:
 205  */
 206 struct lock_chain {
 207         /* see BUILD_BUG_ON()s in lookup_chain_cache() */
 208         unsigned int                    irq_context :  2,
 209                                         depth       :  6,
 210                                         base        : 24;
 211         /* 4 byte hole */
 212         struct hlist_node               entry;
 213         u64                             chain_key;
 214 };
 215
 216 #define MAX_LOCKDEP_KEYS_BITS           13
 217 /*
 218  * Subtract one because we offset hlock->class_idx by 1 in order
 219  * to make 0 mean no class. This avoids overflowing the class_idx
 220  * bitfield and hitting the BUG in hlock_class().
 221  */
 222 #define MAX_LOCKDEP_KEYS                ((1UL << MAX_LOCKDEP_KEYS_BITS) - 1)
 223
 224 struct held_lock {
 225         /*
 226          * One-way hash of the dependency chain up to this point. We
 227          * hash the hashes step by step as the dependency chain grows.
 228          *
 229          * We use it for dependency-caching and we skip detection
 230          * passes and dependency-updates if there is a cache-hit, so
 231          * it is absolutely critical for 100% coverage of the validator
 232          * to have a unique key value for every unique dependency path
 233          * that can occur in the system, to make a unique hash value
 234          * as likely as possible - hence the 64-bit width.
 235          *
 236          * The task struct holds the current hash value (initialized
 237          * with zero), here we store the previous hash value:
 238          */
 239         u64                             prev_chain_key;
 240         unsigned long                   acquire_ip;
 241         struct lockdep_map              *instance;
 242         struct lockdep_map              *nest_lock;
 243 #ifdef CONFIG_LOCK_STAT
 244         u64                             waittime_stamp;
 245         u64                             holdtime_stamp;
 246 #endif
 247         unsigned int                    class_idx:MAX_LOCKDEP_KEYS_BITS;
 248         /*
 249          * The lock-stack is unified in that the lock chains of interrupt
 250          * contexts nest ontop of process context chains, but we 'separate'
 251          * the hashes by starting with 0 if we cross into an interrupt
 252          * context, and we also keep do not add cross-context lock
 253          * dependencies - the lock usage graph walking covers that area
 254          * anyway, and we'd just unnecessarily increase the number of
 255          * dependencies otherwise. [Note: hardirq and softirq contexts
 256          * are separated from each other too.]
 257          *
 258          * The following field is used to detect when we cross into an
 259          * interrupt context:
 260          */
 261         unsigned int irq_context:2; /* bit 0 - soft, bit 1 - hard */
 262         unsigned int trylock:1;                                         /* 16 bits */
 263
 264         unsigned int read:2;        /* see lock_acquire() comment */
 265         unsigned int check:1;       /* see lock_acquire() comment */
 266         unsigned int hardirqs_off:1;
 267         unsigned int references:12;                                     /* 32 bits */
 268         unsigned int pin_count;
 269 #ifdef CONFIG_LOCKDEP_CROSSRELEASE
 270         /*
 271          * Generation id.
 272          *
 273          * A value of cross_gen_id will be stored when holding this,
 274          * which is globally increased whenever each crosslock is held.
 275          */
 276         unsigned int gen_id;
 277 #endif
 278 };
 279
 280 #ifdef CONFIG_LOCKDEP_CROSSRELEASE
 281 #define MAX_XHLOCK_TRACE_ENTRIES 5
 282
 283 /*
 284  * This is for keeping locks waiting for commit so that true dependencies
 285  * can be added at commit step.
 286  */
 287 struct hist_lock {
 288         /*
 289          * Id for each entry in the ring buffer. This is used to
 290          * decide whether the ring buffer was overwritten or not.
 291          *
 292          * For example,
 293          *
 294          *           |<----------- hist_lock ring buffer size ------->|
 295          *           pppppppppppppppppppppiiiiiiiiiiiiiiiiiiiiiiiiiiiii
 296          * wrapped > iiiiiiiiiiiiiiiiiiiiiiiiiii.......................
 297          *
 298          *           where 'p' represents an acquisition in process
 299          *           context, 'i' represents an acquisition in irq
 300          *           context.
 301          *
 302          * In this example, the ring buffer was overwritten by
 303          * acquisitions in irq context, that should be detected on
 304          * rollback or commit.
 305          */
 306         unsigned int hist_id;
 307
 308         /*
 309          * Seperate stack_trace data. This will be used at commit step.
 310          */
 311         struct stack_trace      trace;
 312         unsigned long           trace_entries[MAX_XHLOCK_TRACE_ENTRIES];
 313
 314         /*
 315          * Seperate hlock instance. This will be used at commit step.
 316          *
 317          * TODO: Use a smaller data structure containing only necessary
 318          * data. However, we should make lockdep code able to handle the
 319          * smaller one first.
 320          */
 321         struct held_lock        hlock;
 322 };
 323
 324 /*
 325  * To initialize a lock as crosslock, lockdep_init_map_crosslock() should
 326  * be called instead of lockdep_init_map().
 327  */
 328 struct cross_lock {
 329         /*
 330          * When more than one acquisition of crosslocks are overlapped,
 331          * we have to perform commit for them based on cross_gen_id of
 332          * the first acquisition, which allows us to add more true
 333          * dependencies.
 334          *
 335          * Moreover, when no acquisition of a crosslock is in progress,
 336          * we should not perform commit because the lock might not exist
 337          * any more, which might cause incorrect memory access. So we
 338          * have to track the number of acquisitions of a crosslock.
 339          */
 340         int nr_acquire;
 341
 342         /*
 343          * Seperate hlock instance. This will be used at commit step.
 344          *
 345          * TODO: Use a smaller data structure containing only necessary
 346          * data. However, we should make lockdep code able to handle the
 347          * smaller one first.
 348          */
 349         struct held_lock        hlock;
 350 };
 351
 352 struct lockdep_map_cross {
 353         struct lockdep_map map;
 354         struct cross_lock xlock;
 355 };
 356 #endif
 357
 358 /*
 359  * Initialization, self-test and debugging-output methods:
 360  */
 361 extern void lockdep_info(void);
 362 extern void lockdep_reset(void);
 363 extern void lockdep_reset_lock(struct lockdep_map *lock);
 364 extern void lockdep_free_key_range(void *start, unsigned long size);
 365 extern asmlinkage void lockdep_sys_exit(void);
 366
 367 extern void lockdep_off(void);
 368 extern void lockdep_on(void);
 369
 370 /*
 371  * These methods are used by specific locking variants (spinlocks,
 372  * rwlocks, mutexes and rwsems) to pass init/acquire/release events
 373  * to lockdep:
 374  */
 375
 376 extern void lockdep_init_map(struct lockdep_map *lock, const char *name,
 377                              struct lock_class_key *key, int subclass);
 378
 379 /*
 380  * Reinitialize a lock key - for cases where there is special locking or
 381  * special initialization of locks so that the validator gets the scope
 382  * of dependencies wrong: they are either too broad (they need a class-split)
 383  * or they are too narrow (they suffer from a false class-split):
 384  */
 385 #define lockdep_set_class(lock, key) \
 386                 lockdep_init_map(&(lock)->dep_map, #key, key, 0)
 387 #define lockdep_set_class_and_name(lock, key, name) \
 388                 lockdep_init_map(&(lock)->dep_map, name, key, 0)
 389 #define lockdep_set_class_and_subclass(lock, key, sub) \
 390                 lockdep_init_map(&(lock)->dep_map, #key, key, sub)
 391 #define lockdep_set_subclass(lock, sub) \
 392                 lockdep_init_map(&(lock)->dep_map, #lock, \
 393                                  (lock)->dep_map.key, sub)
 394
 395 #define lockdep_set_novalidate_class(lock) \
 396         lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock)
 397 /*
 398  * Compare locking classes
 399  */
 400 #define lockdep_match_class(lock, key) lockdep_match_key(&(lock)->dep_map, key)
 401
 402 static inline int lockdep_match_key(struct lockdep_map *lock,
 403                                     struct lock_class_key *key)
 404 {
 405         return lock->key == key;
 406 }
 407
 408 /*
 409  * Acquire a lock.
 410  *
 411  * Values for "read":
 412  *
 413  *   0: exclusive (write) acquire
 414  *   1: read-acquire (no recursion allowed)
 415  *   2: read-acquire with same-instance recursion allowed
 416  *
 417  * Values for check:
 418  *
 419  *   0: simple checks (freeing, held-at-exit-time, etc.)
 420  *   1: full validation
 421  */
 422 extern void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 423                          int trylock, int read, int check,
 424                          struct lockdep_map *nest_lock, unsigned long ip);
 425
 426 extern void lock_release(struct lockdep_map *lock, int nested,
 427                          unsigned long ip);
 428
 429 /*
 430  * Same "read" as for lock_acquire(), except -1 means any.
 431  */
 432 extern int lock_is_held_type(struct lockdep_map *lock, int read);
 433
 434 static inline int lock_is_held(struct lockdep_map *lock)
 435 {
 436         return lock_is_held_type(lock, -1);
 437 }
 438
 439 #define lockdep_is_held(lock)           lock_is_held(&(lock)->dep_map)
 440 #define lockdep_is_held_type(lock, r)   lock_is_held_type(&(lock)->dep_map, (r))
 441
 442 extern void lock_set_class(struct lockdep_map *lock, const char *name,
 443                            struct lock_class_key *key, unsigned int subclass,
 444                            unsigned long ip);
 445
 446 static inline void lock_set_subclass(struct lockdep_map *lock,
 447                 unsigned int subclass, unsigned long ip)
 448 {
 449         lock_set_class(lock, lock->name, lock->key, subclass, ip);
 450 }
 451
 452 extern void lock_downgrade(struct lockdep_map *lock, unsigned long ip);
 453
 454 struct pin_cookie { unsigned int val; };
 455
 456 #define NIL_COOKIE (struct pin_cookie){ .val = 0U, }
 457
 458 extern struct pin_cookie lock_pin_lock(struct lockdep_map *lock);
 459 extern void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie);
 460 extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);
 461
 462 # define INIT_LOCKDEP                           .lockdep_recursion = 0,
 463
 464 #define lockdep_depth(tsk)      (debug_locks ? (tsk)->lockdep_depth : 0)
 465
 466 #define lockdep_assert_held(l)  do {                            \
 467                 WARN_ON(debug_locks && !lockdep_is_held(l));    \
 468         } while (0)
 469
 470 #define lockdep_assert_held_exclusive(l)        do {                    \
 471                 WARN_ON(debug_locks && !lockdep_is_held_type(l, 0));    \
 472         } while (0)
 473
 474 #define lockdep_assert_held_read(l)     do {                            \
 475                 WARN_ON(debug_locks && !lockdep_is_held_type(l, 1));    \
 476         } while (0)
 477
 478 #define lockdep_assert_held_once(l)     do {                            \
 479                 WARN_ON_ONCE(debug_locks && !lockdep_is_held(l));       \
 480         } while (0)
 481
 482 #define lockdep_recursing(tsk)  ((tsk)->lockdep_recursion)
 483
 484 #define lockdep_pin_lock(l)     lock_pin_lock(&(l)->dep_map)
 485 #define lockdep_repin_lock(l,c) lock_repin_lock(&(l)->dep_map, (c))
 486 #define lockdep_unpin_lock(l,c) lock_unpin_lock(&(l)->dep_map, (c))
 487
 488 #else /* !CONFIG_LOCKDEP */
 489
 490 static inline void lockdep_off(void)
 491 {
 492 }
 493
 494 static inline void lockdep_on(void)
 495 {
 496 }
 497
 498 # define lock_acquire(l, s, t, r, c, n, i)      do { } while (0)
 499 # define lock_release(l, n, i)                  do { } while (0)
 500 # define lock_downgrade(l, i)                   do { } while (0)
 501 # define lock_set_class(l, n, k, s, i)          do { } while (0)
 502 # define lock_set_subclass(l, s, i)             do { } while (0)
 503 # define lockdep_info()                         do { } while (0)
 504 # define lockdep_init_map(lock, name, key, sub) \
 505                 do { (void)(name); (void)(key); } while (0)
 506 # define lockdep_set_class(lock, key)           do { (void)(key); } while (0)
 507 # define lockdep_set_class_and_name(lock, key, name) \
 508                 do { (void)(key); (void)(name); } while (0)
 509 #define lockdep_set_class_and_subclass(lock, key, sub) \
 510                 do { (void)(key); } while (0)
 511 #define lockdep_set_subclass(lock, sub)         do { } while (0)
 512
 513 #define lockdep_set_novalidate_class(lock) do { } while (0)
 514
 515 /*
 516  * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP
 517  * case since the result is not well defined and the caller should rather
 518  * #ifdef the call himself.
 519  */
 520
 521 # define INIT_LOCKDEP
 522 # define lockdep_reset()                do { debug_locks = 1; } while (0)
 523 # define lockdep_free_key_range(start, size)    do { } while (0)
 524 # define lockdep_sys_exit()                     do { } while (0)
 525 /*
 526  * The class key takes no space if lockdep is disabled:
 527  */
 528 struct lock_class_key { };
 529
 530 #define lockdep_depth(tsk)      (0)
 531
 532 #define lockdep_is_held_type(l, r)              (1)
 533
 534 #define lockdep_assert_held(l)                  do { (void)(l); } while (0)
 535 #define lockdep_assert_held_exclusive(l)        do { (void)(l); } while (0)
 536 #define lockdep_assert_held_read(l)             do { (void)(l); } while (0)
 537 #define lockdep_assert_held_once(l)             do { (void)(l); } while (0)
 538
 539 #define lockdep_recursing(tsk)                  (0)
 540
 541 struct pin_cookie { };
 542
 543 #define NIL_COOKIE (struct pin_cookie){ }
 544
 545 #define lockdep_pin_lock(l)                     ({ struct pin_cookie cookie; cookie; })
 546 #define lockdep_repin_lock(l, c)                do { (void)(l); (void)(c); } while (0)
 547 #define lockdep_unpin_lock(l, c)                do { (void)(l); (void)(c); } while (0)
 548
 549 #endif /* !LOCKDEP */
 550
 551 enum xhlock_context_t {
 552         XHLOCK_HARD,
 553         XHLOCK_SOFT,
 554         XHLOCK_CTX_NR,
 555 };
 556
 557 #ifdef CONFIG_LOCKDEP_CROSSRELEASE
 558 extern void lockdep_init_map_crosslock(struct lockdep_map *lock,
 559                                        const char *name,
 560                                        struct lock_class_key *key,
 561                                        int subclass);
 562 extern void lock_commit_crosslock(struct lockdep_map *lock);
 563
 564 /*
 565  * What we essencially have to initialize is 'nr_acquire'. Other members
 566  * will be initialized in add_xlock().
 567  */
 568 #define STATIC_CROSS_LOCK_INIT() \
 569         { .nr_acquire = 0,}
 570
 571 #define STATIC_CROSS_LOCKDEP_MAP_INIT(_name, _key) \
 572         { .map.name = (_name), .map.key = (void *)(_key), \
 573           .map.cross = 1, .xlock = STATIC_CROSS_LOCK_INIT(), }
 574
 575 /*
 576  * To initialize a lockdep_map statically use this macro.
 577  * Note that _name must not be NULL.
 578  */
 579 #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \
 580         { .name = (_name), .key = (void *)(_key), .cross = 0, }
 581
 582 extern void crossrelease_hist_start(enum xhlock_context_t c);
 583 extern void crossrelease_hist_end(enum xhlock_context_t c);
 584 extern void lockdep_invariant_state(bool force);
 585 extern void lockdep_init_task(struct task_struct *task);
 586 extern void lockdep_free_task(struct task_struct *task);
 587 #else /* !CROSSRELEASE */
 588 #define lockdep_init_map_crosslock(m, n, k, s) do {} while (0)
 589 /*
 590  * To initialize a lockdep_map statically use this macro.
 591  * Note that _name must not be NULL.
 592  */
 593 #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \
 594         { .name = (_name), .key = (void *)(_key), }
 595
 596 static inline void crossrelease_hist_start(enum xhlock_context_t c) {}
 597 static inline void crossrelease_hist_end(enum xhlock_context_t c) {}
 598 static inline void lockdep_invariant_state(bool force) {}
 599 static inline void lockdep_init_task(struct task_struct *task) {}
 600 static inline void lockdep_free_task(struct task_struct *task) {}
 601 #endif /* CROSSRELEASE */
 602
 603 #ifdef CONFIG_LOCK_STAT
 604
 605 extern void lock_contended(struct lockdep_map *lock, unsigned long ip);
 606 extern void lock_acquired(struct lockdep_map *lock, unsigned long ip);
 607
 608 #define LOCK_CONTENDED(_lock, try, lock)                        \
 609 do {                                                            \
 610         if (!try(_lock)) {                                      \
 611                 lock_contended(&(_lock)->dep_map, _RET_IP_);    \
 612                 lock(_lock);                                    \
 613         }                                                       \
 614         lock_acquired(&(_lock)->dep_map, _RET_IP_);                     \
 615 } while (0)
 616
 617 #define LOCK_CONTENDED_RETURN(_lock, try, lock)                 \
 618 ({                                                              \
 619         int ____err = 0;                                        \
 620         if (!try(_lock)) {                                      \
 621                 lock_contended(&(_lock)->dep_map, _RET_IP_);    \
 622                 ____err = lock(_lock);                          \
 623         }                                                       \
 624         if (!____err)                                           \
 625                 lock_acquired(&(_lock)->dep_map, _RET_IP_);     \
 626         ____err;                                                \
 627 })
 628
 629 #else /* CONFIG_LOCK_STAT */
 630
 631 #define lock_contended(lockdep_map, ip) do {} while (0)
 632 #define lock_acquired(lockdep_map, ip) do {} while (0)
 633
 634 #define LOCK_CONTENDED(_lock, try, lock) \
 635         lock(_lock)
 636
 637 #define LOCK_CONTENDED_RETURN(_lock, try, lock) \
 638         lock(_lock)
 639
 640 #endif /* CONFIG_LOCK_STAT */
 641
 642 #ifdef CONFIG_LOCKDEP
 643
 644 /*
 645  * On lockdep we dont want the hand-coded irq-enable of
 646  * _raw_*_lock_flags() code, because lockdep assumes
 647  * that interrupts are not re-enabled during lock-acquire:
 648  */
 649 #define LOCK_CONTENDED_FLAGS(_lock, try, lock, lockfl, flags) \
 650         LOCK_CONTENDED((_lock), (try), (lock))
 651
 652 #else /* CONFIG_LOCKDEP */
 653
 654 #define LOCK_CONTENDED_FLAGS(_lock, try, lock, lockfl, flags) \
 655         lockfl((_lock), (flags))
 656
 657 #endif /* CONFIG_LOCKDEP */
 658
 659 #ifdef CONFIG_TRACE_IRQFLAGS
 660 extern void print_irqtrace_events(struct task_struct *curr);
 661 #else
 662 static inline void print_irqtrace_events(struct task_struct *curr)
 663 {
 664 }
 665 #endif
 666
 667 /*
 668  * For trivial one-depth nesting of a lock-class, the following
 669  * global define can be used. (Subsystems with multiple levels
 670  * of nesting should define their own lock-nesting subclasses.)
 671  */
 672 #define SINGLE_DEPTH_NESTING                    1
 673
 674 /*
 675  * Map the dependency ops to NOP or to real lockdep ops, depending
 676  * on the per lock-class debug mode:
 677  */
 678
 679 #define lock_acquire_exclusive(l, s, t, n, i)           lock_acquire(l, s, t, 0, 1, n, i)
 680 #define lock_acquire_shared(l, s, t, n, i)              lock_acquire(l, s, t, 1, 1, n, i)
 681 #define lock_acquire_shared_recursive(l, s, t, n, i)    lock_acquire(l, s, t, 2, 1, n, i)
 682
 683 #define spin_acquire(l, s, t, i)                lock_acquire_exclusive(l, s, t, NULL, i)
 684 #define spin_acquire_nest(l, s, t, n, i)        lock_acquire_exclusive(l, s, t, n, i)
 685 #define spin_release(l, n, i)                   lock_release(l, n, i)
 686
 687 #define rwlock_acquire(l, s, t, i)              lock_acquire_exclusive(l, s, t, NULL, i)
 688 #define rwlock_acquire_read(l, s, t, i)         lock_acquire_shared_recursive(l, s, t, NULL, i)
 689 #define rwlock_release(l, n, i)                 lock_release(l, n, i)
 690
 691 #define seqcount_acquire(l, s, t, i)            lock_acquire_exclusive(l, s, t, NULL, i)
 692 #define seqcount_acquire_read(l, s, t, i)       lock_acquire_shared_recursive(l, s, t, NULL, i)
 693 #define seqcount_release(l, n, i)               lock_release(l, n, i)
 694
 695 #define mutex_acquire(l, s, t, i)               lock_acquire_exclusive(l, s, t, NULL, i)
 696 #define mutex_acquire_nest(l, s, t, n, i)       lock_acquire_exclusive(l, s, t, n, i)
 697 #define mutex_release(l, n, i)                  lock_release(l, n, i)
 698
 699 #define rwsem_acquire(l, s, t, i)               lock_acquire_exclusive(l, s, t, NULL, i)
 700 #define rwsem_acquire_nest(l, s, t, n, i)       lock_acquire_exclusive(l, s, t, n, i)
 701 #define rwsem_acquire_read(l, s, t, i)          lock_acquire_shared(l, s, t, NULL, i)
 702 #define rwsem_release(l, n, i)                  lock_release(l, n, i)
 703
 704 #define lock_map_acquire(l)                     lock_acquire_exclusive(l, 0, 0, NULL, _THIS_IP_)
 705 #define lock_map_acquire_read(l)                lock_acquire_shared_recursive(l, 0, 0, NULL, _THIS_IP_)
 706 #define lock_map_acquire_tryread(l)             lock_acquire_shared_recursive(l, 0, 1, NULL, _THIS_IP_)
 707 #define lock_map_release(l)                     lock_release(l, 1, _THIS_IP_)
 708
 709 #ifdef CONFIG_PROVE_LOCKING
 710 # define might_lock(lock)                                               \
 711 do {                                                                    \
 712         typecheck(struct lockdep_map *, &(lock)->dep_map);              \
 713         lock_acquire(&(lock)->dep_map, 0, 0, 0, 1, NULL, _THIS_IP_);    \
 714         lock_release(&(lock)->dep_map, 0, _THIS_IP_);                   \
 715 } while (0)
 716 # define might_lock_read(lock)                                          \
 717 do {                                                                    \
 718         typecheck(struct lockdep_map *, &(lock)->dep_map);              \
 719         lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_);    \
 720         lock_release(&(lock)->dep_map, 0, _THIS_IP_);                   \
 721 } while (0)
 722 #else
 723 # define might_lock(lock) do { } while (0)
 724 # define might_lock_read(lock) do { } while (0)
 725 #endif
 726
 727 #ifdef CONFIG_LOCKDEP
 728 void lockdep_rcu_suspicious(const char *file, const int line, const char *s);
 729 #else
 730 static inline void
 731 lockdep_rcu_suspicious(const char *file, const int line, const char *s)
 732 {
 733 }
 734 #endif
 735
 736 #endif /* __LINUX_LOCKDEP_H */