include/linux/wait.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_WAIT_H
   3 #define _LINUX_WAIT_H
   4 /*
   5  * Linux wait queue related types and methods
   6  */
   7 #include <linux/list.h>
   8 #include <linux/stddef.h>
   9 #include <linux/spinlock.h>
  10
  11 #include <asm/current.h>
  12 #include <uapi/linux/wait.h>
  13
  14 typedef struct wait_queue_entry wait_queue_entry_t;
  15
  16 typedef int (*wait_queue_func_t)(struct wait_queue_entry *wq_entry, unsigned mode, int flags, void *key);
  17 int default_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int flags, void *key);
  18
  19 /* wait_queue_entry::flags */
  20 #define WQ_FLAG_EXCLUSIVE       0x01
  21 #define WQ_FLAG_WOKEN           0x02
  22 #define WQ_FLAG_BOOKMARK        0x04
  23
  24 /*
  25  * A single wait-queue entry structure:
  26  */
  27 struct wait_queue_entry {
  28         unsigned int            flags;
  29         void                    *private;
  30         wait_queue_func_t       func;
  31         struct list_head        entry;
  32 };
  33
  34 struct wait_queue_head {
  35         spinlock_t              lock;
  36         struct list_head        head;
  37 };
  38 typedef struct wait_queue_head wait_queue_head_t;
  39
  40 struct task_struct;
  41
  42 /*
  43  * Macros for declaration and initialisaton of the datatypes
  44  */
  45
  46 #define __WAITQUEUE_INITIALIZER(name, tsk) {                                    \
  47         .private        = tsk,                                                  \
  48         .func           = default_wake_function,                                \
  49         .entry          = { NULL, NULL } }
  50
  51 #define DECLARE_WAITQUEUE(name, tsk)                                            \
  52         struct wait_queue_entry name = __WAITQUEUE_INITIALIZER(name, tsk)
  53
  54 #define __WAIT_QUEUE_HEAD_INITIALIZER(name) {                                   \
  55         .lock           = __SPIN_LOCK_UNLOCKED(name.lock),                      \
  56         .head           = { &(name).head, &(name).head } }
  57
  58 #define DECLARE_WAIT_QUEUE_HEAD(name) \
  59         struct wait_queue_head name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
  60
  61 extern void __init_waitqueue_head(struct wait_queue_head *wq_head, const char *name, struct lock_class_key *);
  62
  63 #define init_waitqueue_head(wq_head)                                            \
  64         do {                                                                    \
  65                 static struct lock_class_key __key;                             \
  66                                                                                 \
  67                 __init_waitqueue_head((wq_head), #wq_head, &__key);             \
  68         } while (0)
  69
  70 #ifdef CONFIG_LOCKDEP
  71 # define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
  72         ({ init_waitqueue_head(&name); name; })
  73 # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
  74         struct wait_queue_head name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
  75 #else
  76 # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
  77 #endif
  78
  79 static inline void init_waitqueue_entry(struct wait_queue_entry *wq_entry, struct task_struct *p)
  80 {
  81         wq_entry->flags         = 0;
  82         wq_entry->private       = p;
  83         wq_entry->func          = default_wake_function;
  84 }
  85
  86 static inline void
  87 init_waitqueue_func_entry(struct wait_queue_entry *wq_entry, wait_queue_func_t func)
  88 {
  89         wq_entry->flags         = 0;
  90         wq_entry->private       = NULL;
  91         wq_entry->func          = func;
  92 }
  93
  94 /**
  95  * waitqueue_active -- locklessly test for waiters on the queue
  96  * @wq_head: the waitqueue to test for waiters
  97  *
  98  * returns true if the wait list is not empty
  99  *
 100  * NOTE: this function is lockless and requires care, incorrect usage _will_
 101  * lead to sporadic and non-obvious failure.
 102  *
 103  * Use either while holding wait_queue_head::lock or when used for wakeups
 104  * with an extra smp_mb() like::
 105  *
 106  *      CPU0 - waker                    CPU1 - waiter
 107  *
 108  *                                      for (;;) {
 109  *      @cond = true;                     prepare_to_wait(&wq_head, &wait, state);
 110  *      smp_mb();                         // smp_mb() from set_current_state()
 111  *      if (waitqueue_active(wq_head))         if (@cond)
 112  *        wake_up(wq_head);                      break;
 113  *                                        schedule();
 114  *                                      }
 115  *                                      finish_wait(&wq_head, &wait);
 116  *
 117  * Because without the explicit smp_mb() it's possible for the
 118  * waitqueue_active() load to get hoisted over the @cond store such that we'll
 119  * observe an empty wait list while the waiter might not observe @cond.
 120  *
 121  * Also note that this 'optimization' trades a spin_lock() for an smp_mb(),
 122  * which (when the lock is uncontended) are of roughly equal cost.
 123  */
 124 static inline int waitqueue_active(struct wait_queue_head *wq_head)
 125 {
 126         return !list_empty(&wq_head->head);
 127 }
 128
 129 /**
 130  * wq_has_single_sleeper - check if there is only one sleeper
 131  * @wq_head: wait queue head
 132  *
 133  * Returns true of wq_head has only one sleeper on the list.
 134  *
 135  * Please refer to the comment for waitqueue_active.
 136  */
 137 static inline bool wq_has_single_sleeper(struct wait_queue_head *wq_head)
 138 {
 139         return list_is_singular(&wq_head->head);
 140 }
 141
 142 /**
 143  * wq_has_sleeper - check if there are any waiting processes
 144  * @wq_head: wait queue head
 145  *
 146  * Returns true if wq_head has waiting processes
 147  *
 148  * Please refer to the comment for waitqueue_active.
 149  */
 150 static inline bool wq_has_sleeper(struct wait_queue_head *wq_head)
 151 {
 152         /*
 153          * We need to be sure we are in sync with the
 154          * add_wait_queue modifications to the wait queue.
 155          *
 156          * This memory barrier should be paired with one on the
 157          * waiting side.
 158          */
 159         smp_mb();
 160         return waitqueue_active(wq_head);
 161 }
 162
 163 extern void add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
 164 extern void add_wait_queue_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
 165 extern void remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
 166
 167 static inline void __add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 168 {
 169         list_add(&wq_entry->entry, &wq_head->head);
 170 }
 171
 172 /*
 173  * Used for wake-one threads:
 174  */
 175 static inline void
 176 __add_wait_queue_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 177 {
 178         wq_entry->flags |= WQ_FLAG_EXCLUSIVE;
 179         __add_wait_queue(wq_head, wq_entry);
 180 }
 181
 182 static inline void __add_wait_queue_entry_tail(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 183 {
 184         list_add_tail(&wq_entry->entry, &wq_head->head);
 185 }
 186
 187 static inline void
 188 __add_wait_queue_entry_tail_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 189 {
 190         wq_entry->flags |= WQ_FLAG_EXCLUSIVE;
 191         __add_wait_queue_entry_tail(wq_head, wq_entry);
 192 }
 193
 194 static inline void
 195 __remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 196 {
 197         list_del(&wq_entry->entry);
 198 }
 199
 200 void __wake_up(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key);
 201 void __wake_up_locked_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
 202 void __wake_up_locked_key_bookmark(struct wait_queue_head *wq_head,
 203                 unsigned int mode, void *key, wait_queue_entry_t *bookmark);
 204 void __wake_up_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
 205 void __wake_up_locked_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
 206 void __wake_up_locked(struct wait_queue_head *wq_head, unsigned int mode, int nr);
 207 void __wake_up_sync(struct wait_queue_head *wq_head, unsigned int mode);
 208
 209 #define wake_up(x)                      __wake_up(x, TASK_NORMAL, 1, NULL)
 210 #define wake_up_nr(x, nr)               __wake_up(x, TASK_NORMAL, nr, NULL)
 211 #define wake_up_all(x)                  __wake_up(x, TASK_NORMAL, 0, NULL)
 212 #define wake_up_locked(x)               __wake_up_locked((x), TASK_NORMAL, 1)
 213 #define wake_up_all_locked(x)           __wake_up_locked((x), TASK_NORMAL, 0)
 214
 215 #define wake_up_interruptible(x)        __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
 216 #define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
 217 #define wake_up_interruptible_all(x)    __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
 218 #define wake_up_interruptible_sync(x)   __wake_up_sync((x), TASK_INTERRUPTIBLE)
 219
 220 /*
 221  * Wakeup macros to be used to report events to the targets.
 222  */
 223 #define poll_to_key(m) ((void *)(__force uintptr_t)(__poll_t)(m))
 224 #define key_to_poll(m) ((__force __poll_t)(uintptr_t)(void *)(m))
 225 #define wake_up_poll(x, m)                                                      \
 226         __wake_up(x, TASK_NORMAL, 1, poll_to_key(m))
 227 #define wake_up_locked_poll(x, m)                                               \
 228         __wake_up_locked_key((x), TASK_NORMAL, poll_to_key(m))
 229 #define wake_up_interruptible_poll(x, m)                                        \
 230         __wake_up(x, TASK_INTERRUPTIBLE, 1, poll_to_key(m))
 231 #define wake_up_interruptible_sync_poll(x, m)                                   \
 232         __wake_up_sync_key((x), TASK_INTERRUPTIBLE, poll_to_key(m))
 233 #define wake_up_interruptible_sync_poll_locked(x, m)                            \
 234         __wake_up_locked_sync_key((x), TASK_INTERRUPTIBLE, poll_to_key(m))
 235
 236 #define ___wait_cond_timeout(condition)                                         \
 237 ({                                                                              \
 238         bool __cond = (condition);                                              \
 239         if (__cond && !__ret)                                                   \
 240                 __ret = 1;                                                      \
 241         __cond || !__ret;                                                       \
 242 })
 243
 244 #define ___wait_is_interruptible(state)                                         \
 245         (!__builtin_constant_p(state) ||                                        \
 246                 state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE)          \
 247
 248 extern void init_wait_entry(struct wait_queue_entry *wq_entry, int flags);
 249
 250 /*
 251  * The below macro ___wait_event() has an explicit shadow of the __ret
 252  * variable when used from the wait_event_*() macros.
 253  *
 254  * This is so that both can use the ___wait_cond_timeout() construct
 255  * to wrap the condition.
 256  *
 257  * The type inconsistency of the wait_event_*() __ret variable is also
 258  * on purpose; we use long where we can return timeout values and int
 259  * otherwise.
 260  */
 261
 262 #define ___wait_event(wq_head, condition, state, exclusive, ret, cmd)           \
 263 ({                                                                              \
 264         __label__ __out;                                                        \
 265         struct wait_queue_entry __wq_entry;                                     \
 266         long __ret = ret;       /* explicit shadow */                           \
 267                                                                                 \
 268         init_wait_entry(&__wq_entry, exclusive ? WQ_FLAG_EXCLUSIVE : 0);        \
 269         for (;;) {                                                              \
 270                 long __int = prepare_to_wait_event(&wq_head, &__wq_entry, state);\
 271                                                                                 \
 272                 if (condition)                                                  \
 273                         break;                                                  \
 274                                                                                 \
 275                 if (___wait_is_interruptible(state) && __int) {                 \
 276                         __ret = __int;                                          \
 277                         goto __out;                                             \
 278                 }                                                               \
 279                                                                                 \
 280                 cmd;                                                            \
 281         }                                                                       \
 282         finish_wait(&wq_head, &__wq_entry);                                     \
 283 __out:  __ret;                                                                  \
 284 })
 285
 286 #define __wait_event(wq_head, condition)                                        \
 287         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0,     \
 288                             schedule())
 289
 290 /**
 291  * wait_event - sleep until a condition gets true
 292  * @wq_head: the waitqueue to wait on
 293  * @condition: a C expression for the event to wait for
 294  *
 295  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 296  * @condition evaluates to true. The @condition is checked each time
 297  * the waitqueue @wq_head is woken up.
 298  *
 299  * wake_up() has to be called after changing any variable that could
 300  * change the result of the wait condition.
 301  */
 302 #define wait_event(wq_head, condition)                                          \
 303 do {                                                                            \
 304         might_sleep();                                                          \
 305         if (condition)                                                          \
 306                 break;                                                          \
 307         __wait_event(wq_head, condition);                                       \
 308 } while (0)
 309
 310 #define __io_wait_event(wq_head, condition)                                     \
 311         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0,     \
 312                             io_schedule())
 313
 314 /*
 315  * io_wait_event() -- like wait_event() but with io_schedule()
 316  */
 317 #define io_wait_event(wq_head, condition)                                       \
 318 do {                                                                            \
 319         might_sleep();                                                          \
 320         if (condition)                                                          \
 321                 break;                                                          \
 322         __io_wait_event(wq_head, condition);                                    \
 323 } while (0)
 324
 325 #define __wait_event_freezable(wq_head, condition)                              \
 326         ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0,             \
 327                             freezable_schedule())
 328
 329 /**
 330  * wait_event_freezable - sleep (or freeze) until a condition gets true
 331  * @wq_head: the waitqueue to wait on
 332  * @condition: a C expression for the event to wait for
 333  *
 334  * The process is put to sleep (TASK_INTERRUPTIBLE -- so as not to contribute
 335  * to system load) until the @condition evaluates to true. The
 336  * @condition is checked each time the waitqueue @wq_head is woken up.
 337  *
 338  * wake_up() has to be called after changing any variable that could
 339  * change the result of the wait condition.
 340  */
 341 #define wait_event_freezable(wq_head, condition)                                \
 342 ({                                                                              \
 343         int __ret = 0;                                                          \
 344         might_sleep();                                                          \
 345         if (!(condition))                                                       \
 346                 __ret = __wait_event_freezable(wq_head, condition);             \
 347         __ret;                                                                  \
 348 })
 349
 350 #define __wait_event_timeout(wq_head, condition, timeout)                       \
 351         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 352                       TASK_UNINTERRUPTIBLE, 0, timeout,                         \
 353                       __ret = schedule_timeout(__ret))
 354
 355 /**
 356  * wait_event_timeout - sleep until a condition gets true or a timeout elapses
 357  * @wq_head: the waitqueue to wait on
 358  * @condition: a C expression for the event to wait for
 359  * @timeout: timeout, in jiffies
 360  *
 361  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 362  * @condition evaluates to true. The @condition is checked each time
 363  * the waitqueue @wq_head is woken up.
 364  *
 365  * wake_up() has to be called after changing any variable that could
 366  * change the result of the wait condition.
 367  *
 368  * Returns:
 369  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 370  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 371  * or the remaining jiffies (at least 1) if the @condition evaluated
 372  * to %true before the @timeout elapsed.
 373  */
 374 #define wait_event_timeout(wq_head, condition, timeout)                         \
 375 ({                                                                              \
 376         long __ret = timeout;                                                   \
 377         might_sleep();                                                          \
 378         if (!___wait_cond_timeout(condition))                                   \
 379                 __ret = __wait_event_timeout(wq_head, condition, timeout);      \
 380         __ret;                                                                  \
 381 })
 382
 383 #define __wait_event_freezable_timeout(wq_head, condition, timeout)             \
 384         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 385                       TASK_INTERRUPTIBLE, 0, timeout,                           \
 386                       __ret = freezable_schedule_timeout(__ret))
 387
 388 /*
 389  * like wait_event_timeout() -- except it uses TASK_INTERRUPTIBLE to avoid
 390  * increasing load and is freezable.
 391  */
 392 #define wait_event_freezable_timeout(wq_head, condition, timeout)               \
 393 ({                                                                              \
 394         long __ret = timeout;                                                   \
 395         might_sleep();                                                          \
 396         if (!___wait_cond_timeout(condition))                                   \
 397                 __ret = __wait_event_freezable_timeout(wq_head, condition, timeout); \
 398         __ret;                                                                  \
 399 })
 400
 401 #define __wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2)              \
 402         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 1, 0,     \
 403                             cmd1; schedule(); cmd2)
 404 /*
 405  * Just like wait_event_cmd(), except it sets exclusive flag
 406  */
 407 #define wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2)                \
 408 do {                                                                            \
 409         if (condition)                                                          \
 410                 break;                                                          \
 411         __wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2);             \
 412 } while (0)
 413
 414 #define __wait_event_cmd(wq_head, condition, cmd1, cmd2)                        \
 415         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0,     \
 416                             cmd1; schedule(); cmd2)
 417
 418 /**
 419  * wait_event_cmd - sleep until a condition gets true
 420  * @wq_head: the waitqueue to wait on
 421  * @condition: a C expression for the event to wait for
 422  * @cmd1: the command will be executed before sleep
 423  * @cmd2: the command will be executed after sleep
 424  *
 425  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 426  * @condition evaluates to true. The @condition is checked each time
 427  * the waitqueue @wq_head is woken up.
 428  *
 429  * wake_up() has to be called after changing any variable that could
 430  * change the result of the wait condition.
 431  */
 432 #define wait_event_cmd(wq_head, condition, cmd1, cmd2)                          \
 433 do {                                                                            \
 434         if (condition)                                                          \
 435                 break;                                                          \
 436         __wait_event_cmd(wq_head, condition, cmd1, cmd2);                       \
 437 } while (0)
 438
 439 #define __wait_event_interruptible(wq_head, condition)                          \
 440         ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0,             \
 441                       schedule())
 442
 443 /**
 444  * wait_event_interruptible - sleep until a condition gets true
 445  * @wq_head: the waitqueue to wait on
 446  * @condition: a C expression for the event to wait for
 447  *
 448  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 449  * @condition evaluates to true or a signal is received.
 450  * The @condition is checked each time the waitqueue @wq_head is woken up.
 451  *
 452  * wake_up() has to be called after changing any variable that could
 453  * change the result of the wait condition.
 454  *
 455  * The function will return -ERESTARTSYS if it was interrupted by a
 456  * signal and 0 if @condition evaluated to true.
 457  */
 458 #define wait_event_interruptible(wq_head, condition)                            \
 459 ({                                                                              \
 460         int __ret = 0;                                                          \
 461         might_sleep();                                                          \
 462         if (!(condition))                                                       \
 463                 __ret = __wait_event_interruptible(wq_head, condition);         \
 464         __ret;                                                                  \
 465 })
 466
 467 #define __wait_event_interruptible_timeout(wq_head, condition, timeout)         \
 468         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 469                       TASK_INTERRUPTIBLE, 0, timeout,                           \
 470                       __ret = schedule_timeout(__ret))
 471
 472 /**
 473  * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
 474  * @wq_head: the waitqueue to wait on
 475  * @condition: a C expression for the event to wait for
 476  * @timeout: timeout, in jiffies
 477  *
 478  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 479  * @condition evaluates to true or a signal is received.
 480  * The @condition is checked each time the waitqueue @wq_head is woken up.
 481  *
 482  * wake_up() has to be called after changing any variable that could
 483  * change the result of the wait condition.
 484  *
 485  * Returns:
 486  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 487  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 488  * the remaining jiffies (at least 1) if the @condition evaluated
 489  * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was
 490  * interrupted by a signal.
 491  */
 492 #define wait_event_interruptible_timeout(wq_head, condition, timeout)           \
 493 ({                                                                              \
 494         long __ret = timeout;                                                   \
 495         might_sleep();                                                          \
 496         if (!___wait_cond_timeout(condition))                                   \
 497                 __ret = __wait_event_interruptible_timeout(wq_head,             \
 498                                                 condition, timeout);            \
 499         __ret;                                                                  \
 500 })
 501
 502 #define __wait_event_hrtimeout(wq_head, condition, timeout, state)              \
 503 ({                                                                              \
 504         int __ret = 0;                                                          \
 505         struct hrtimer_sleeper __t;                                             \
 506                                                                                 \
 507         hrtimer_init_sleeper_on_stack(&__t, CLOCK_MONOTONIC,                    \
 508                                       HRTIMER_MODE_REL);                        \
 509         if ((timeout) != KTIME_MAX)                                             \
 510                 hrtimer_start_range_ns(&__t.timer, timeout,                     \
 511                                        current->timer_slack_ns,                 \
 512                                        HRTIMER_MODE_REL);                       \
 513                                                                                 \
 514         __ret = ___wait_event(wq_head, condition, state, 0, 0,                  \
 515                 if (!__t.task) {                                                \
 516                         __ret = -ETIME;                                         \
 517                         break;                                                  \
 518                 }                                                               \
 519                 schedule());                                                    \
 520                                                                                 \
 521         hrtimer_cancel(&__t.timer);                                             \
 522         destroy_hrtimer_on_stack(&__t.timer);                                   \
 523         __ret;                                                                  \
 524 })
 525
 526 /**
 527  * wait_event_hrtimeout - sleep until a condition gets true or a timeout elapses
 528  * @wq_head: the waitqueue to wait on
 529  * @condition: a C expression for the event to wait for
 530  * @timeout: timeout, as a ktime_t
 531  *
 532  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 533  * @condition evaluates to true or a signal is received.
 534  * The @condition is checked each time the waitqueue @wq_head is woken up.
 535  *
 536  * wake_up() has to be called after changing any variable that could
 537  * change the result of the wait condition.
 538  *
 539  * The function returns 0 if @condition became true, or -ETIME if the timeout
 540  * elapsed.
 541  */
 542 #define wait_event_hrtimeout(wq_head, condition, timeout)                       \
 543 ({                                                                              \
 544         int __ret = 0;                                                          \
 545         might_sleep();                                                          \
 546         if (!(condition))                                                       \
 547                 __ret = __wait_event_hrtimeout(wq_head, condition, timeout,     \
 548                                                TASK_UNINTERRUPTIBLE);           \
 549         __ret;                                                                  \
 550 })
 551
 552 /**
 553  * wait_event_interruptible_hrtimeout - sleep until a condition gets true or a timeout elapses
 554  * @wq: the waitqueue to wait on
 555  * @condition: a C expression for the event to wait for
 556  * @timeout: timeout, as a ktime_t
 557  *
 558  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 559  * @condition evaluates to true or a signal is received.
 560  * The @condition is checked each time the waitqueue @wq is woken up.
 561  *
 562  * wake_up() has to be called after changing any variable that could
 563  * change the result of the wait condition.
 564  *
 565  * The function returns 0 if @condition became true, -ERESTARTSYS if it was
 566  * interrupted by a signal, or -ETIME if the timeout elapsed.
 567  */
 568 #define wait_event_interruptible_hrtimeout(wq, condition, timeout)              \
 569 ({                                                                              \
 570         long __ret = 0;                                                         \
 571         might_sleep();                                                          \
 572         if (!(condition))                                                       \
 573                 __ret = __wait_event_hrtimeout(wq, condition, timeout,          \
 574                                                TASK_INTERRUPTIBLE);             \
 575         __ret;                                                                  \
 576 })
 577
 578 #define __wait_event_interruptible_exclusive(wq, condition)                     \
 579         ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0,                  \
 580                       schedule())
 581
 582 #define wait_event_interruptible_exclusive(wq, condition)                       \
 583 ({                                                                              \
 584         int __ret = 0;                                                          \
 585         might_sleep();                                                          \
 586         if (!(condition))                                                       \
 587                 __ret = __wait_event_interruptible_exclusive(wq, condition);    \
 588         __ret;                                                                  \
 589 })
 590
 591 #define __wait_event_killable_exclusive(wq, condition)                          \
 592         ___wait_event(wq, condition, TASK_KILLABLE, 1, 0,                       \
 593                       schedule())
 594
 595 #define wait_event_killable_exclusive(wq, condition)                            \
 596 ({                                                                              \
 597         int __ret = 0;                                                          \
 598         might_sleep();                                                          \
 599         if (!(condition))                                                       \
 600                 __ret = __wait_event_killable_exclusive(wq, condition);         \
 601         __ret;                                                                  \
 602 })
 603
 604
 605 #define __wait_event_freezable_exclusive(wq, condition)                         \
 606         ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0,                  \
 607                         freezable_schedule())
 608
 609 #define wait_event_freezable_exclusive(wq, condition)                           \
 610 ({                                                                              \
 611         int __ret = 0;                                                          \
 612         might_sleep();                                                          \
 613         if (!(condition))                                                       \
 614                 __ret = __wait_event_freezable_exclusive(wq, condition);        \
 615         __ret;                                                                  \
 616 })
 617
 618 /**
 619  * wait_event_idle - wait for a condition without contributing to system load
 620  * @wq_head: the waitqueue to wait on
 621  * @condition: a C expression for the event to wait for
 622  *
 623  * The process is put to sleep (TASK_IDLE) until the
 624  * @condition evaluates to true.
 625  * The @condition is checked each time the waitqueue @wq_head is woken up.
 626  *
 627  * wake_up() has to be called after changing any variable that could
 628  * change the result of the wait condition.
 629  *
 630  */
 631 #define wait_event_idle(wq_head, condition)                                     \
 632 do {                                                                            \
 633         might_sleep();                                                          \
 634         if (!(condition))                                                       \
 635                 ___wait_event(wq_head, condition, TASK_IDLE, 0, 0, schedule()); \
 636 } while (0)
 637
 638 /**
 639  * wait_event_idle_exclusive - wait for a condition with contributing to system load
 640  * @wq_head: the waitqueue to wait on
 641  * @condition: a C expression for the event to wait for
 642  *
 643  * The process is put to sleep (TASK_IDLE) until the
 644  * @condition evaluates to true.
 645  * The @condition is checked each time the waitqueue @wq_head is woken up.
 646  *
 647  * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
 648  * set thus if other processes wait on the same list, when this
 649  * process is woken further processes are not considered.
 650  *
 651  * wake_up() has to be called after changing any variable that could
 652  * change the result of the wait condition.
 653  *
 654  */
 655 #define wait_event_idle_exclusive(wq_head, condition)                           \
 656 do {                                                                            \
 657         might_sleep();                                                          \
 658         if (!(condition))                                                       \
 659                 ___wait_event(wq_head, condition, TASK_IDLE, 1, 0, schedule()); \
 660 } while (0)
 661
 662 #define __wait_event_idle_timeout(wq_head, condition, timeout)                  \
 663         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 664                       TASK_IDLE, 0, timeout,                                    \
 665                       __ret = schedule_timeout(__ret))
 666
 667 /**
 668  * wait_event_idle_timeout - sleep without load until a condition becomes true or a timeout elapses
 669  * @wq_head: the waitqueue to wait on
 670  * @condition: a C expression for the event to wait for
 671  * @timeout: timeout, in jiffies
 672  *
 673  * The process is put to sleep (TASK_IDLE) until the
 674  * @condition evaluates to true. The @condition is checked each time
 675  * the waitqueue @wq_head is woken up.
 676  *
 677  * wake_up() has to be called after changing any variable that could
 678  * change the result of the wait condition.
 679  *
 680  * Returns:
 681  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 682  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 683  * or the remaining jiffies (at least 1) if the @condition evaluated
 684  * to %true before the @timeout elapsed.
 685  */
 686 #define wait_event_idle_timeout(wq_head, condition, timeout)                    \
 687 ({                                                                              \
 688         long __ret = timeout;                                                   \
 689         might_sleep();                                                          \
 690         if (!___wait_cond_timeout(condition))                                   \
 691                 __ret = __wait_event_idle_timeout(wq_head, condition, timeout); \
 692         __ret;                                                                  \
 693 })
 694
 695 #define __wait_event_idle_exclusive_timeout(wq_head, condition, timeout)        \
 696         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 697                       TASK_IDLE, 1, timeout,                                    \
 698                       __ret = schedule_timeout(__ret))
 699
 700 /**
 701  * wait_event_idle_exclusive_timeout - sleep without load until a condition becomes true or a timeout elapses
 702  * @wq_head: the waitqueue to wait on
 703  * @condition: a C expression for the event to wait for
 704  * @timeout: timeout, in jiffies
 705  *
 706  * The process is put to sleep (TASK_IDLE) until the
 707  * @condition evaluates to true. The @condition is checked each time
 708  * the waitqueue @wq_head is woken up.
 709  *
 710  * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
 711  * set thus if other processes wait on the same list, when this
 712  * process is woken further processes are not considered.
 713  *
 714  * wake_up() has to be called after changing any variable that could
 715  * change the result of the wait condition.
 716  *
 717  * Returns:
 718  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 719  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 720  * or the remaining jiffies (at least 1) if the @condition evaluated
 721  * to %true before the @timeout elapsed.
 722  */
 723 #define wait_event_idle_exclusive_timeout(wq_head, condition, timeout)          \
 724 ({                                                                              \
 725         long __ret = timeout;                                                   \
 726         might_sleep();                                                          \
 727         if (!___wait_cond_timeout(condition))                                   \
 728                 __ret = __wait_event_idle_exclusive_timeout(wq_head, condition, timeout);\
 729         __ret;                                                                  \
 730 })
 731
 732 extern int do_wait_intr(wait_queue_head_t *, wait_queue_entry_t *);
 733 extern int do_wait_intr_irq(wait_queue_head_t *, wait_queue_entry_t *);
 734
 735 #define __wait_event_interruptible_locked(wq, condition, exclusive, fn)         \
 736 ({                                                                              \
 737         int __ret;                                                              \
 738         DEFINE_WAIT(__wait);                                                    \
 739         if (exclusive)                                                          \
 740                 __wait.flags |= WQ_FLAG_EXCLUSIVE;                              \
 741         do {                                                                    \
 742                 __ret = fn(&(wq), &__wait);                                     \
 743                 if (__ret)                                                      \
 744                         break;                                                  \
 745         } while (!(condition));                                                 \
 746         __remove_wait_queue(&(wq), &__wait);                                    \
 747         __set_current_state(TASK_RUNNING);                                      \
 748         __ret;                                                                  \
 749 })
 750
 751
 752 /**
 753  * wait_event_interruptible_locked - sleep until a condition gets true
 754  * @wq: the waitqueue to wait on
 755  * @condition: a C expression for the event to wait for
 756  *
 757  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 758  * @condition evaluates to true or a signal is received.
 759  * The @condition is checked each time the waitqueue @wq is woken up.
 760  *
 761  * It must be called with wq.lock being held.  This spinlock is
 762  * unlocked while sleeping but @condition testing is done while lock
 763  * is held and when this macro exits the lock is held.
 764  *
 765  * The lock is locked/unlocked using spin_lock()/spin_unlock()
 766  * functions which must match the way they are locked/unlocked outside
 767  * of this macro.
 768  *
 769  * wake_up_locked() has to be called after changing any variable that could
 770  * change the result of the wait condition.
 771  *
 772  * The function will return -ERESTARTSYS if it was interrupted by a
 773  * signal and 0 if @condition evaluated to true.
 774  */
 775 #define wait_event_interruptible_locked(wq, condition)                          \
 776         ((condition)                                                            \
 777          ? 0 : __wait_event_interruptible_locked(wq, condition, 0, do_wait_intr))
 778
 779 /**
 780  * wait_event_interruptible_locked_irq - sleep until a condition gets true
 781  * @wq: the waitqueue to wait on
 782  * @condition: a C expression for the event to wait for
 783  *
 784  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 785  * @condition evaluates to true or a signal is received.
 786  * The @condition is checked each time the waitqueue @wq is woken up.
 787  *
 788  * It must be called with wq.lock being held.  This spinlock is
 789  * unlocked while sleeping but @condition testing is done while lock
 790  * is held and when this macro exits the lock is held.
 791  *
 792  * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
 793  * functions which must match the way they are locked/unlocked outside
 794  * of this macro.
 795  *
 796  * wake_up_locked() has to be called after changing any variable that could
 797  * change the result of the wait condition.
 798  *
 799  * The function will return -ERESTARTSYS if it was interrupted by a
 800  * signal and 0 if @condition evaluated to true.
 801  */
 802 #define wait_event_interruptible_locked_irq(wq, condition)                      \
 803         ((condition)                                                            \
 804          ? 0 : __wait_event_interruptible_locked(wq, condition, 0, do_wait_intr_irq))
 805
 806 /**
 807  * wait_event_interruptible_exclusive_locked - sleep exclusively until a condition gets true
 808  * @wq: the waitqueue to wait on
 809  * @condition: a C expression for the event to wait for
 810  *
 811  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 812  * @condition evaluates to true or a signal is received.
 813  * The @condition is checked each time the waitqueue @wq is woken up.
 814  *
 815  * It must be called with wq.lock being held.  This spinlock is
 816  * unlocked while sleeping but @condition testing is done while lock
 817  * is held and when this macro exits the lock is held.
 818  *
 819  * The lock is locked/unlocked using spin_lock()/spin_unlock()
 820  * functions which must match the way they are locked/unlocked outside
 821  * of this macro.
 822  *
 823  * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
 824  * set thus when other process waits process on the list if this
 825  * process is awaken further processes are not considered.
 826  *
 827  * wake_up_locked() has to be called after changing any variable that could
 828  * change the result of the wait condition.
 829  *
 830  * The function will return -ERESTARTSYS if it was interrupted by a
 831  * signal and 0 if @condition evaluated to true.
 832  */
 833 #define wait_event_interruptible_exclusive_locked(wq, condition)                \
 834         ((condition)                                                            \
 835          ? 0 : __wait_event_interruptible_locked(wq, condition, 1, do_wait_intr))
 836
 837 /**
 838  * wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true
 839  * @wq: the waitqueue to wait on
 840  * @condition: a C expression for the event to wait for
 841  *
 842  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 843  * @condition evaluates to true or a signal is received.
 844  * The @condition is checked each time the waitqueue @wq is woken up.
 845  *
 846  * It must be called with wq.lock being held.  This spinlock is
 847  * unlocked while sleeping but @condition testing is done while lock
 848  * is held and when this macro exits the lock is held.
 849  *
 850  * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
 851  * functions which must match the way they are locked/unlocked outside
 852  * of this macro.
 853  *
 854  * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
 855  * set thus when other process waits process on the list if this
 856  * process is awaken further processes are not considered.
 857  *
 858  * wake_up_locked() has to be called after changing any variable that could
 859  * change the result of the wait condition.
 860  *
 861  * The function will return -ERESTARTSYS if it was interrupted by a
 862  * signal and 0 if @condition evaluated to true.
 863  */
 864 #define wait_event_interruptible_exclusive_locked_irq(wq, condition)            \
 865         ((condition)                                                            \
 866          ? 0 : __wait_event_interruptible_locked(wq, condition, 1, do_wait_intr_irq))
 867
 868
 869 #define __wait_event_killable(wq, condition)                                    \
 870         ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule())
 871
 872 /**
 873  * wait_event_killable - sleep until a condition gets true
 874  * @wq_head: the waitqueue to wait on
 875  * @condition: a C expression for the event to wait for
 876  *
 877  * The process is put to sleep (TASK_KILLABLE) until the
 878  * @condition evaluates to true or a signal is received.
 879  * The @condition is checked each time the waitqueue @wq_head is woken up.
 880  *
 881  * wake_up() has to be called after changing any variable that could
 882  * change the result of the wait condition.
 883  *
 884  * The function will return -ERESTARTSYS if it was interrupted by a
 885  * signal and 0 if @condition evaluated to true.
 886  */
 887 #define wait_event_killable(wq_head, condition)                                 \
 888 ({                                                                              \
 889         int __ret = 0;                                                          \
 890         might_sleep();                                                          \
 891         if (!(condition))                                                       \
 892                 __ret = __wait_event_killable(wq_head, condition);              \
 893         __ret;                                                                  \
 894 })
 895
 896 #define __wait_event_killable_timeout(wq_head, condition, timeout)              \
 897         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 898                       TASK_KILLABLE, 0, timeout,                                \
 899                       __ret = schedule_timeout(__ret))
 900
 901 /**
 902  * wait_event_killable_timeout - sleep until a condition gets true or a timeout elapses
 903  * @wq_head: the waitqueue to wait on
 904  * @condition: a C expression for the event to wait for
 905  * @timeout: timeout, in jiffies
 906  *
 907  * The process is put to sleep (TASK_KILLABLE) until the
 908  * @condition evaluates to true or a kill signal is received.
 909  * The @condition is checked each time the waitqueue @wq_head is woken up.
 910  *
 911  * wake_up() has to be called after changing any variable that could
 912  * change the result of the wait condition.
 913  *
 914  * Returns:
 915  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 916  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 917  * the remaining jiffies (at least 1) if the @condition evaluated
 918  * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was
 919  * interrupted by a kill signal.
 920  *
 921  * Only kill signals interrupt this process.
 922  */
 923 #define wait_event_killable_timeout(wq_head, condition, timeout)                \
 924 ({                                                                              \
 925         long __ret = timeout;                                                   \
 926         might_sleep();                                                          \
 927         if (!___wait_cond_timeout(condition))                                   \
 928                 __ret = __wait_event_killable_timeout(wq_head,                  \
 929                                                 condition, timeout);            \
 930         __ret;                                                                  \
 931 })
 932
 933
 934 #define __wait_event_lock_irq(wq_head, condition, lock, cmd)                    \
 935         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0,     \
 936                             spin_unlock_irq(&lock);                             \
 937                             cmd;                                                \
 938                             schedule();                                         \
 939                             spin_lock_irq(&lock))
 940
 941 /**
 942  * wait_event_lock_irq_cmd - sleep until a condition gets true. The
 943  *                           condition is checked under the lock. This
 944  *                           is expected to be called with the lock
 945  *                           taken.
 946  * @wq_head: the waitqueue to wait on
 947  * @condition: a C expression for the event to wait for
 948  * @lock: a locked spinlock_t, which will be released before cmd
 949  *        and schedule() and reacquired afterwards.
 950  * @cmd: a command which is invoked outside the critical section before
 951  *       sleep
 952  *
 953  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 954  * @condition evaluates to true. The @condition is checked each time
 955  * the waitqueue @wq_head is woken up.
 956  *
 957  * wake_up() has to be called after changing any variable that could
 958  * change the result of the wait condition.
 959  *
 960  * This is supposed to be called while holding the lock. The lock is
 961  * dropped before invoking the cmd and going to sleep and is reacquired
 962  * afterwards.
 963  */
 964 #define wait_event_lock_irq_cmd(wq_head, condition, lock, cmd)                  \
 965 do {                                                                            \
 966         if (condition)                                                          \
 967                 break;                                                          \
 968         __wait_event_lock_irq(wq_head, condition, lock, cmd);                   \
 969 } while (0)
 970
 971 /**
 972  * wait_event_lock_irq - sleep until a condition gets true. The
 973  *                       condition is checked under the lock. This
 974  *                       is expected to be called with the lock
 975  *                       taken.
 976  * @wq_head: the waitqueue to wait on
 977  * @condition: a C expression for the event to wait for
 978  * @lock: a locked spinlock_t, which will be released before schedule()
 979  *        and reacquired afterwards.
 980  *
 981  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 982  * @condition evaluates to true. The @condition is checked each time
 983  * the waitqueue @wq_head is woken up.
 984  *
 985  * wake_up() has to be called after changing any variable that could
 986  * change the result of the wait condition.
 987  *
 988  * This is supposed to be called while holding the lock. The lock is
 989  * dropped before going to sleep and is reacquired afterwards.
 990  */
 991 #define wait_event_lock_irq(wq_head, condition, lock)                           \
 992 do {                                                                            \
 993         if (condition)                                                          \
 994                 break;                                                          \
 995         __wait_event_lock_irq(wq_head, condition, lock, );                      \
 996 } while (0)
 997
 998
 999 #define __wait_event_interruptible_lock_irq(wq_head, condition, lock, cmd)      \
1000         ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0,             \
1001                       spin_unlock_irq(&lock);                                   \
1002                       cmd;                                                      \
1003                       schedule();                                               \
1004                       spin_lock_irq(&lock))
1005
1006 /**
1007  * wait_event_interruptible_lock_irq_cmd - sleep until a condition gets true.
1008  *              The condition is checked under the lock. This is expected to
1009  *              be called with the lock taken.
1010  * @wq_head: the waitqueue to wait on
1011  * @condition: a C expression for the event to wait for
1012  * @lock: a locked spinlock_t, which will be released before cmd and
1013  *        schedule() and reacquired afterwards.
1014  * @cmd: a command which is invoked outside the critical section before
1015  *       sleep
1016  *
1017  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1018  * @condition evaluates to true or a signal is received. The @condition is
1019  * checked each time the waitqueue @wq_head is woken up.
1020  *
1021  * wake_up() has to be called after changing any variable that could
1022  * change the result of the wait condition.
1023  *
1024  * This is supposed to be called while holding the lock. The lock is
1025  * dropped before invoking the cmd and going to sleep and is reacquired
1026  * afterwards.
1027  *
1028  * The macro will return -ERESTARTSYS if it was interrupted by a signal
1029  * and 0 if @condition evaluated to true.
1030  */
1031 #define wait_event_interruptible_lock_irq_cmd(wq_head, condition, lock, cmd)    \
1032 ({                                                                              \
1033         int __ret = 0;                                                          \
1034         if (!(condition))                                                       \
1035                 __ret = __wait_event_interruptible_lock_irq(wq_head,            \
1036                                                 condition, lock, cmd);          \
1037         __ret;                                                                  \
1038 })
1039
1040 /**
1041  * wait_event_interruptible_lock_irq - sleep until a condition gets true.
1042  *              The condition is checked under the lock. This is expected
1043  *              to be called with the lock taken.
1044  * @wq_head: the waitqueue to wait on
1045  * @condition: a C expression for the event to wait for
1046  * @lock: a locked spinlock_t, which will be released before schedule()
1047  *        and reacquired afterwards.
1048  *
1049  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1050  * @condition evaluates to true or signal is received. The @condition is
1051  * checked each time the waitqueue @wq_head is woken up.
1052  *
1053  * wake_up() has to be called after changing any variable that could
1054  * change the result of the wait condition.
1055  *
1056  * This is supposed to be called while holding the lock. The lock is
1057  * dropped before going to sleep and is reacquired afterwards.
1058  *
1059  * The macro will return -ERESTARTSYS if it was interrupted by a signal
1060  * and 0 if @condition evaluated to true.
1061  */
1062 #define wait_event_interruptible_lock_irq(wq_head, condition, lock)             \
1063 ({                                                                              \
1064         int __ret = 0;                                                          \
1065         if (!(condition))                                                       \
1066                 __ret = __wait_event_interruptible_lock_irq(wq_head,            \
1067                                                 condition, lock,);              \
1068         __ret;                                                                  \
1069 })
1070
1071 #define __wait_event_lock_irq_timeout(wq_head, condition, lock, timeout, state) \
1072         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
1073                       state, 0, timeout,                                        \
1074                       spin_unlock_irq(&lock);                                   \
1075                       __ret = schedule_timeout(__ret);                          \
1076                       spin_lock_irq(&lock));
1077
1078 /**
1079  * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets
1080  *              true or a timeout elapses. The condition is checked under
1081  *              the lock. This is expected to be called with the lock taken.
1082  * @wq_head: the waitqueue to wait on
1083  * @condition: a C expression for the event to wait for
1084  * @lock: a locked spinlock_t, which will be released before schedule()
1085  *        and reacquired afterwards.
1086  * @timeout: timeout, in jiffies
1087  *
1088  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1089  * @condition evaluates to true or signal is received. The @condition is
1090  * checked each time the waitqueue @wq_head is woken up.
1091  *
1092  * wake_up() has to be called after changing any variable that could
1093  * change the result of the wait condition.
1094  *
1095  * This is supposed to be called while holding the lock. The lock is
1096  * dropped before going to sleep and is reacquired afterwards.
1097  *
1098  * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
1099  * was interrupted by a signal, and the remaining jiffies otherwise
1100  * if the condition evaluated to true before the timeout elapsed.
1101  */
1102 #define wait_event_interruptible_lock_irq_timeout(wq_head, condition, lock,     \
1103                                                   timeout)                      \
1104 ({                                                                              \
1105         long __ret = timeout;                                                   \
1106         if (!___wait_cond_timeout(condition))                                   \
1107                 __ret = __wait_event_lock_irq_timeout(                          \
1108                                         wq_head, condition, lock, timeout,      \
1109                                         TASK_INTERRUPTIBLE);                    \
1110         __ret;                                                                  \
1111 })
1112
1113 #define wait_event_lock_irq_timeout(wq_head, condition, lock, timeout)          \
1114 ({                                                                              \
1115         long __ret = timeout;                                                   \
1116         if (!___wait_cond_timeout(condition))                                   \
1117                 __ret = __wait_event_lock_irq_timeout(                          \
1118                                         wq_head, condition, lock, timeout,      \
1119                                         TASK_UNINTERRUPTIBLE);                  \
1120         __ret;                                                                  \
1121 })
1122
1123 /*
1124  * Waitqueues which are removed from the waitqueue_head at wakeup time
1125  */
1126 void prepare_to_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1127 void prepare_to_wait_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1128 long prepare_to_wait_event(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1129 void finish_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
1130 long wait_woken(struct wait_queue_entry *wq_entry, unsigned mode, long timeout);
1131 int woken_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
1132 int autoremove_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
1133
1134 #define DEFINE_WAIT_FUNC(name, function)                                        \
1135         struct wait_queue_entry name = {                                        \
1136                 .private        = current,                                      \
1137                 .func           = function,                                     \
1138                 .entry          = LIST_HEAD_INIT((name).entry),                 \
1139         }
1140
1141 #define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
1142
1143 #define init_wait(wait)                                                         \
1144         do {                                                                    \
1145                 (wait)->private = current;                                      \
1146                 (wait)->func = autoremove_wake_function;                        \
1147                 INIT_LIST_HEAD(&(wait)->entry);                                 \
1148                 (wait)->flags = 0;                                              \
1149         } while (0)
1150
1151 #endif /* _LINUX_WAIT_H */