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 #define WQ_FLAG_CUSTOM          0x08
  24 #define WQ_FLAG_DONE            0x10
  25 #define WQ_FLAG_PRIORITY        0x20
  26
  27 /*
  28  * A single wait-queue entry structure:
  29  */
  30 struct wait_queue_entry {
  31         unsigned int            flags;
  32         void                    *private;
  33         wait_queue_func_t       func;
  34         struct list_head        entry;
  35 };
  36
  37 struct wait_queue_head {
  38         spinlock_t              lock;
  39         struct list_head        head;
  40 };
  41 typedef struct wait_queue_head wait_queue_head_t;
  42
  43 struct task_struct;
  44
  45 /*
  46  * Macros for declaration and initialisaton of the datatypes
  47  */
  48
  49 #define __WAITQUEUE_INITIALIZER(name, tsk) {                                    \
  50         .private        = tsk,                                                  \
  51         .func           = default_wake_function,                                \
  52         .entry          = { NULL, NULL } }
  53
  54 #define DECLARE_WAITQUEUE(name, tsk)                                            \
  55         struct wait_queue_entry name = __WAITQUEUE_INITIALIZER(name, tsk)
  56
  57 #define __WAIT_QUEUE_HEAD_INITIALIZER(name) {                                   \
  58         .lock           = __SPIN_LOCK_UNLOCKED(name.lock),                      \
  59         .head           = LIST_HEAD_INIT(name.head) }
  60
  61 #define DECLARE_WAIT_QUEUE_HEAD(name) \
  62         struct wait_queue_head name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
  63
  64 extern void __init_waitqueue_head(struct wait_queue_head *wq_head, const char *name, struct lock_class_key *);
  65
  66 #define init_waitqueue_head(wq_head)                                            \
  67         do {                                                                    \
  68                 static struct lock_class_key __key;                             \
  69                                                                                 \
  70                 __init_waitqueue_head((wq_head), #wq_head, &__key);             \
  71         } while (0)
  72
  73 #ifdef CONFIG_LOCKDEP
  74 # define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
  75         ({ init_waitqueue_head(&name); name; })
  76 # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
  77         struct wait_queue_head name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
  78 #else
  79 # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
  80 #endif
  81
  82 static inline void init_waitqueue_entry(struct wait_queue_entry *wq_entry, struct task_struct *p)
  83 {
  84         wq_entry->flags         = 0;
  85         wq_entry->private       = p;
  86         wq_entry->func          = default_wake_function;
  87 }
  88
  89 static inline void
  90 init_waitqueue_func_entry(struct wait_queue_entry *wq_entry, wait_queue_func_t func)
  91 {
  92         wq_entry->flags         = 0;
  93         wq_entry->private       = NULL;
  94         wq_entry->func          = func;
  95 }
  96
  97 /**
  98  * waitqueue_active -- locklessly test for waiters on the queue
  99  * @wq_head: the waitqueue to test for waiters
 100  *
 101  * returns true if the wait list is not empty
 102  *
 103  * NOTE: this function is lockless and requires care, incorrect usage _will_
 104  * lead to sporadic and non-obvious failure.
 105  *
 106  * Use either while holding wait_queue_head::lock or when used for wakeups
 107  * with an extra smp_mb() like::
 108  *
 109  *      CPU0 - waker                    CPU1 - waiter
 110  *
 111  *                                      for (;;) {
 112  *      @cond = true;                     prepare_to_wait(&wq_head, &wait, state);
 113  *      smp_mb();                         // smp_mb() from set_current_state()
 114  *      if (waitqueue_active(wq_head))         if (@cond)
 115  *        wake_up(wq_head);                      break;
 116  *                                        schedule();
 117  *                                      }
 118  *                                      finish_wait(&wq_head, &wait);
 119  *
 120  * Because without the explicit smp_mb() it's possible for the
 121  * waitqueue_active() load to get hoisted over the @cond store such that we'll
 122  * observe an empty wait list while the waiter might not observe @cond.
 123  *
 124  * Also note that this 'optimization' trades a spin_lock() for an smp_mb(),
 125  * which (when the lock is uncontended) are of roughly equal cost.
 126  */
 127 static inline int waitqueue_active(struct wait_queue_head *wq_head)
 128 {
 129         return !list_empty(&wq_head->head);
 130 }
 131
 132 /**
 133  * wq_has_single_sleeper - check if there is only one sleeper
 134  * @wq_head: wait queue head
 135  *
 136  * Returns true of wq_head has only one sleeper on the list.
 137  *
 138  * Please refer to the comment for waitqueue_active.
 139  */
 140 static inline bool wq_has_single_sleeper(struct wait_queue_head *wq_head)
 141 {
 142         return list_is_singular(&wq_head->head);
 143 }
 144
 145 /**
 146  * wq_has_sleeper - check if there are any waiting processes
 147  * @wq_head: wait queue head
 148  *
 149  * Returns true if wq_head has waiting processes
 150  *
 151  * Please refer to the comment for waitqueue_active.
 152  */
 153 static inline bool wq_has_sleeper(struct wait_queue_head *wq_head)
 154 {
 155         /*
 156          * We need to be sure we are in sync with the
 157          * add_wait_queue modifications to the wait queue.
 158          *
 159          * This memory barrier should be paired with one on the
 160          * waiting side.
 161          */
 162         smp_mb();
 163         return waitqueue_active(wq_head);
 164 }
 165
 166 extern void add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
 167 extern void add_wait_queue_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
 168 extern void add_wait_queue_priority(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
 169 extern void remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
 170
 171 static inline void __add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 172 {
 173         struct list_head *head = &wq_head->head;
 174         struct wait_queue_entry *wq;
 175
 176         list_for_each_entry(wq, &wq_head->head, entry) {
 177                 if (!(wq->flags & WQ_FLAG_PRIORITY))
 178                         break;
 179                 head = &wq->entry;
 180         }
 181         list_add(&wq_entry->entry, head);
 182 }
 183
 184 /*
 185  * Used for wake-one threads:
 186  */
 187 static inline void
 188 __add_wait_queue_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(wq_head, wq_entry);
 192 }
 193
 194 static inline void __add_wait_queue_entry_tail(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 195 {
 196         list_add_tail(&wq_entry->entry, &wq_head->head);
 197 }
 198
 199 static inline void
 200 __add_wait_queue_entry_tail_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 201 {
 202         wq_entry->flags |= WQ_FLAG_EXCLUSIVE;
 203         __add_wait_queue_entry_tail(wq_head, wq_entry);
 204 }
 205
 206 static inline void
 207 __remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
 208 {
 209         list_del(&wq_entry->entry);
 210 }
 211
 212 int __wake_up(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key);
 213 void __wake_up_on_current_cpu(struct wait_queue_head *wq_head, unsigned int mode, void *key);
 214 void __wake_up_locked_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
 215 void __wake_up_locked_key_bookmark(struct wait_queue_head *wq_head,
 216                 unsigned int mode, void *key, wait_queue_entry_t *bookmark);
 217 void __wake_up_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
 218 void __wake_up_locked_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
 219 void __wake_up_locked(struct wait_queue_head *wq_head, unsigned int mode, int nr);
 220 void __wake_up_sync(struct wait_queue_head *wq_head, unsigned int mode);
 221 void __wake_up_pollfree(struct wait_queue_head *wq_head);
 222
 223 #define wake_up(x)                      __wake_up(x, TASK_NORMAL, 1, NULL)
 224 #define wake_up_nr(x, nr)               __wake_up(x, TASK_NORMAL, nr, NULL)
 225 #define wake_up_all(x)                  __wake_up(x, TASK_NORMAL, 0, NULL)
 226 #define wake_up_locked(x)               __wake_up_locked((x), TASK_NORMAL, 1)
 227 #define wake_up_all_locked(x)           __wake_up_locked((x), TASK_NORMAL, 0)
 228
 229 #define wake_up_interruptible(x)        __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
 230 #define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
 231 #define wake_up_interruptible_all(x)    __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
 232 #define wake_up_interruptible_sync(x)   __wake_up_sync((x), TASK_INTERRUPTIBLE)
 233
 234 /*
 235  * Wakeup macros to be used to report events to the targets.
 236  */
 237 #define poll_to_key(m) ((void *)(__force uintptr_t)(__poll_t)(m))
 238 #define key_to_poll(m) ((__force __poll_t)(uintptr_t)(void *)(m))
 239 #define wake_up_poll(x, m)                                                      \
 240         __wake_up(x, TASK_NORMAL, 1, poll_to_key(m))
 241 #define wake_up_poll_on_current_cpu(x, m)                                       \
 242         __wake_up_on_current_cpu(x, TASK_NORMAL, poll_to_key(m))
 243 #define wake_up_locked_poll(x, m)                                               \
 244         __wake_up_locked_key((x), TASK_NORMAL, poll_to_key(m))
 245 #define wake_up_interruptible_poll(x, m)                                        \
 246         __wake_up(x, TASK_INTERRUPTIBLE, 1, poll_to_key(m))
 247 #define wake_up_interruptible_sync_poll(x, m)                                   \
 248         __wake_up_sync_key((x), TASK_INTERRUPTIBLE, poll_to_key(m))
 249 #define wake_up_interruptible_sync_poll_locked(x, m)                            \
 250         __wake_up_locked_sync_key((x), TASK_INTERRUPTIBLE, poll_to_key(m))
 251
 252 /**
 253  * wake_up_pollfree - signal that a polled waitqueue is going away
 254  * @wq_head: the wait queue head
 255  *
 256  * In the very rare cases where a ->poll() implementation uses a waitqueue whose
 257  * lifetime is tied to a task rather than to the 'struct file' being polled,
 258  * this function must be called before the waitqueue is freed so that
 259  * non-blocking polls (e.g. epoll) are notified that the queue is going away.
 260  *
 261  * The caller must also RCU-delay the freeing of the wait_queue_head, e.g. via
 262  * an explicit synchronize_rcu() or call_rcu(), or via SLAB_TYPESAFE_BY_RCU.
 263  */
 264 static inline void wake_up_pollfree(struct wait_queue_head *wq_head)
 265 {
 266         /*
 267          * For performance reasons, we don't always take the queue lock here.
 268          * Therefore, we might race with someone removing the last entry from
 269          * the queue, and proceed while they still hold the queue lock.
 270          * However, rcu_read_lock() is required to be held in such cases, so we
 271          * can safely proceed with an RCU-delayed free.
 272          */
 273         if (waitqueue_active(wq_head))
 274                 __wake_up_pollfree(wq_head);
 275 }
 276
 277 #define ___wait_cond_timeout(condition)                                         \
 278 ({                                                                              \
 279         bool __cond = (condition);                                              \
 280         if (__cond && !__ret)                                                   \
 281                 __ret = 1;                                                      \
 282         __cond || !__ret;                                                       \
 283 })
 284
 285 #define ___wait_is_interruptible(state)                                         \
 286         (!__builtin_constant_p(state) ||                                        \
 287          (state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
 288
 289 extern void init_wait_entry(struct wait_queue_entry *wq_entry, int flags);
 290
 291 /*
 292  * The below macro ___wait_event() has an explicit shadow of the __ret
 293  * variable when used from the wait_event_*() macros.
 294  *
 295  * This is so that both can use the ___wait_cond_timeout() construct
 296  * to wrap the condition.
 297  *
 298  * The type inconsistency of the wait_event_*() __ret variable is also
 299  * on purpose; we use long where we can return timeout values and int
 300  * otherwise.
 301  */
 302
 303 #define ___wait_event(wq_head, condition, state, exclusive, ret, cmd)           \
 304 ({                                                                              \
 305         __label__ __out;                                                        \
 306         struct wait_queue_entry __wq_entry;                                     \
 307         long __ret = ret;       /* explicit shadow */                           \
 308                                                                                 \
 309         init_wait_entry(&__wq_entry, exclusive ? WQ_FLAG_EXCLUSIVE : 0);        \
 310         for (;;) {                                                              \
 311                 long __int = prepare_to_wait_event(&wq_head, &__wq_entry, state);\
 312                                                                                 \
 313                 if (condition)                                                  \
 314                         break;                                                  \
 315                                                                                 \
 316                 if (___wait_is_interruptible(state) && __int) {                 \
 317                         __ret = __int;                                          \
 318                         goto __out;                                             \
 319                 }                                                               \
 320                                                                                 \
 321                 cmd;                                                            \
 322         }                                                                       \
 323         finish_wait(&wq_head, &__wq_entry);                                     \
 324 __out:  __ret;                                                                  \
 325 })
 326
 327 #define __wait_event(wq_head, condition)                                        \
 328         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0,     \
 329                             schedule())
 330
 331 /**
 332  * wait_event - sleep until a condition gets true
 333  * @wq_head: the waitqueue to wait on
 334  * @condition: a C expression for the event to wait for
 335  *
 336  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 337  * @condition evaluates to true. The @condition is checked each time
 338  * the waitqueue @wq_head is woken up.
 339  *
 340  * wake_up() has to be called after changing any variable that could
 341  * change the result of the wait condition.
 342  */
 343 #define wait_event(wq_head, condition)                                          \
 344 do {                                                                            \
 345         might_sleep();                                                          \
 346         if (condition)                                                          \
 347                 break;                                                          \
 348         __wait_event(wq_head, condition);                                       \
 349 } while (0)
 350
 351 #define __io_wait_event(wq_head, condition)                                     \
 352         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0,     \
 353                             io_schedule())
 354
 355 /*
 356  * io_wait_event() -- like wait_event() but with io_schedule()
 357  */
 358 #define io_wait_event(wq_head, condition)                                       \
 359 do {                                                                            \
 360         might_sleep();                                                          \
 361         if (condition)                                                          \
 362                 break;                                                          \
 363         __io_wait_event(wq_head, condition);                                    \
 364 } while (0)
 365
 366 #define __wait_event_freezable(wq_head, condition)                              \
 367         ___wait_event(wq_head, condition, (TASK_INTERRUPTIBLE|TASK_FREEZABLE),  \
 368                         0, 0, schedule())
 369
 370 /**
 371  * wait_event_freezable - sleep (or freeze) until a condition gets true
 372  * @wq_head: the waitqueue to wait on
 373  * @condition: a C expression for the event to wait for
 374  *
 375  * The process is put to sleep (TASK_INTERRUPTIBLE -- so as not to contribute
 376  * to system load) until the @condition evaluates to true. The
 377  * @condition is checked each time the waitqueue @wq_head is woken up.
 378  *
 379  * wake_up() has to be called after changing any variable that could
 380  * change the result of the wait condition.
 381  */
 382 #define wait_event_freezable(wq_head, condition)                                \
 383 ({                                                                              \
 384         int __ret = 0;                                                          \
 385         might_sleep();                                                          \
 386         if (!(condition))                                                       \
 387                 __ret = __wait_event_freezable(wq_head, condition);             \
 388         __ret;                                                                  \
 389 })
 390
 391 #define __wait_event_timeout(wq_head, condition, timeout)                       \
 392         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 393                       TASK_UNINTERRUPTIBLE, 0, timeout,                         \
 394                       __ret = schedule_timeout(__ret))
 395
 396 /**
 397  * wait_event_timeout - sleep until a condition gets true or a timeout elapses
 398  * @wq_head: the waitqueue to wait on
 399  * @condition: a C expression for the event to wait for
 400  * @timeout: timeout, in jiffies
 401  *
 402  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 403  * @condition evaluates to true. The @condition is checked each time
 404  * the waitqueue @wq_head is woken up.
 405  *
 406  * wake_up() has to be called after changing any variable that could
 407  * change the result of the wait condition.
 408  *
 409  * Returns:
 410  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 411  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 412  * or the remaining jiffies (at least 1) if the @condition evaluated
 413  * to %true before the @timeout elapsed.
 414  */
 415 #define wait_event_timeout(wq_head, condition, timeout)                         \
 416 ({                                                                              \
 417         long __ret = timeout;                                                   \
 418         might_sleep();                                                          \
 419         if (!___wait_cond_timeout(condition))                                   \
 420                 __ret = __wait_event_timeout(wq_head, condition, timeout);      \
 421         __ret;                                                                  \
 422 })
 423
 424 #define __wait_event_freezable_timeout(wq_head, condition, timeout)             \
 425         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 426                       (TASK_INTERRUPTIBLE|TASK_FREEZABLE), 0, timeout,          \
 427                       __ret = schedule_timeout(__ret))
 428
 429 /*
 430  * like wait_event_timeout() -- except it uses TASK_INTERRUPTIBLE to avoid
 431  * increasing load and is freezable.
 432  */
 433 #define wait_event_freezable_timeout(wq_head, condition, timeout)               \
 434 ({                                                                              \
 435         long __ret = timeout;                                                   \
 436         might_sleep();                                                          \
 437         if (!___wait_cond_timeout(condition))                                   \
 438                 __ret = __wait_event_freezable_timeout(wq_head, condition, timeout); \
 439         __ret;                                                                  \
 440 })
 441
 442 #define __wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2)              \
 443         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 1, 0,     \
 444                             cmd1; schedule(); cmd2)
 445 /*
 446  * Just like wait_event_cmd(), except it sets exclusive flag
 447  */
 448 #define wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2)                \
 449 do {                                                                            \
 450         if (condition)                                                          \
 451                 break;                                                          \
 452         __wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2);             \
 453 } while (0)
 454
 455 #define __wait_event_cmd(wq_head, condition, cmd1, cmd2)                        \
 456         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0,     \
 457                             cmd1; schedule(); cmd2)
 458
 459 /**
 460  * wait_event_cmd - sleep until a condition gets true
 461  * @wq_head: the waitqueue to wait on
 462  * @condition: a C expression for the event to wait for
 463  * @cmd1: the command will be executed before sleep
 464  * @cmd2: the command will be executed after sleep
 465  *
 466  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 467  * @condition evaluates to true. The @condition is checked each time
 468  * the waitqueue @wq_head is woken up.
 469  *
 470  * wake_up() has to be called after changing any variable that could
 471  * change the result of the wait condition.
 472  */
 473 #define wait_event_cmd(wq_head, condition, cmd1, cmd2)                          \
 474 do {                                                                            \
 475         if (condition)                                                          \
 476                 break;                                                          \
 477         __wait_event_cmd(wq_head, condition, cmd1, cmd2);                       \
 478 } while (0)
 479
 480 #define __wait_event_interruptible(wq_head, condition)                          \
 481         ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0,             \
 482                       schedule())
 483
 484 /**
 485  * wait_event_interruptible - sleep until a condition gets true
 486  * @wq_head: the waitqueue to wait on
 487  * @condition: a C expression for the event to wait for
 488  *
 489  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 490  * @condition evaluates to true or a signal is received.
 491  * The @condition is checked each time the waitqueue @wq_head is woken up.
 492  *
 493  * wake_up() has to be called after changing any variable that could
 494  * change the result of the wait condition.
 495  *
 496  * The function will return -ERESTARTSYS if it was interrupted by a
 497  * signal and 0 if @condition evaluated to true.
 498  */
 499 #define wait_event_interruptible(wq_head, condition)                            \
 500 ({                                                                              \
 501         int __ret = 0;                                                          \
 502         might_sleep();                                                          \
 503         if (!(condition))                                                       \
 504                 __ret = __wait_event_interruptible(wq_head, condition);         \
 505         __ret;                                                                  \
 506 })
 507
 508 #define __wait_event_interruptible_timeout(wq_head, condition, timeout)         \
 509         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 510                       TASK_INTERRUPTIBLE, 0, timeout,                           \
 511                       __ret = schedule_timeout(__ret))
 512
 513 /**
 514  * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
 515  * @wq_head: the waitqueue to wait on
 516  * @condition: a C expression for the event to wait for
 517  * @timeout: timeout, in jiffies
 518  *
 519  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 520  * @condition evaluates to true or a signal is received.
 521  * The @condition is checked each time the waitqueue @wq_head is woken up.
 522  *
 523  * wake_up() has to be called after changing any variable that could
 524  * change the result of the wait condition.
 525  *
 526  * Returns:
 527  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 528  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 529  * the remaining jiffies (at least 1) if the @condition evaluated
 530  * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was
 531  * interrupted by a signal.
 532  */
 533 #define wait_event_interruptible_timeout(wq_head, condition, timeout)           \
 534 ({                                                                              \
 535         long __ret = timeout;                                                   \
 536         might_sleep();                                                          \
 537         if (!___wait_cond_timeout(condition))                                   \
 538                 __ret = __wait_event_interruptible_timeout(wq_head,             \
 539                                                 condition, timeout);            \
 540         __ret;                                                                  \
 541 })
 542
 543 #define __wait_event_hrtimeout(wq_head, condition, timeout, state)              \
 544 ({                                                                              \
 545         int __ret = 0;                                                          \
 546         struct hrtimer_sleeper __t;                                             \
 547                                                                                 \
 548         hrtimer_init_sleeper_on_stack(&__t, CLOCK_MONOTONIC,                    \
 549                                       HRTIMER_MODE_REL);                        \
 550         if ((timeout) != KTIME_MAX) {                                           \
 551                 hrtimer_set_expires_range_ns(&__t.timer, timeout,               \
 552                                         current->timer_slack_ns);               \
 553                 hrtimer_sleeper_start_expires(&__t, HRTIMER_MODE_REL);          \
 554         }                                                                       \
 555                                                                                 \
 556         __ret = ___wait_event(wq_head, condition, state, 0, 0,                  \
 557                 if (!__t.task) {                                                \
 558                         __ret = -ETIME;                                         \
 559                         break;                                                  \
 560                 }                                                               \
 561                 schedule());                                                    \
 562                                                                                 \
 563         hrtimer_cancel(&__t.timer);                                             \
 564         destroy_hrtimer_on_stack(&__t.timer);                                   \
 565         __ret;                                                                  \
 566 })
 567
 568 /**
 569  * wait_event_hrtimeout - sleep until a condition gets true or a timeout elapses
 570  * @wq_head: the waitqueue to wait on
 571  * @condition: a C expression for the event to wait for
 572  * @timeout: timeout, as a ktime_t
 573  *
 574  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 575  * @condition evaluates to true or a signal is received.
 576  * The @condition is checked each time the waitqueue @wq_head is woken up.
 577  *
 578  * wake_up() has to be called after changing any variable that could
 579  * change the result of the wait condition.
 580  *
 581  * The function returns 0 if @condition became true, or -ETIME if the timeout
 582  * elapsed.
 583  */
 584 #define wait_event_hrtimeout(wq_head, condition, timeout)                       \
 585 ({                                                                              \
 586         int __ret = 0;                                                          \
 587         might_sleep();                                                          \
 588         if (!(condition))                                                       \
 589                 __ret = __wait_event_hrtimeout(wq_head, condition, timeout,     \
 590                                                TASK_UNINTERRUPTIBLE);           \
 591         __ret;                                                                  \
 592 })
 593
 594 /**
 595  * wait_event_interruptible_hrtimeout - sleep until a condition gets true or a timeout elapses
 596  * @wq: the waitqueue to wait on
 597  * @condition: a C expression for the event to wait for
 598  * @timeout: timeout, as a ktime_t
 599  *
 600  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 601  * @condition evaluates to true or a signal is received.
 602  * The @condition is checked each time the waitqueue @wq is woken up.
 603  *
 604  * wake_up() has to be called after changing any variable that could
 605  * change the result of the wait condition.
 606  *
 607  * The function returns 0 if @condition became true, -ERESTARTSYS if it was
 608  * interrupted by a signal, or -ETIME if the timeout elapsed.
 609  */
 610 #define wait_event_interruptible_hrtimeout(wq, condition, timeout)              \
 611 ({                                                                              \
 612         long __ret = 0;                                                         \
 613         might_sleep();                                                          \
 614         if (!(condition))                                                       \
 615                 __ret = __wait_event_hrtimeout(wq, condition, timeout,          \
 616                                                TASK_INTERRUPTIBLE);             \
 617         __ret;                                                                  \
 618 })
 619
 620 #define __wait_event_interruptible_exclusive(wq, condition)                     \
 621         ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0,                  \
 622                       schedule())
 623
 624 #define wait_event_interruptible_exclusive(wq, condition)                       \
 625 ({                                                                              \
 626         int __ret = 0;                                                          \
 627         might_sleep();                                                          \
 628         if (!(condition))                                                       \
 629                 __ret = __wait_event_interruptible_exclusive(wq, condition);    \
 630         __ret;                                                                  \
 631 })
 632
 633 #define __wait_event_killable_exclusive(wq, condition)                          \
 634         ___wait_event(wq, condition, TASK_KILLABLE, 1, 0,                       \
 635                       schedule())
 636
 637 #define wait_event_killable_exclusive(wq, condition)                            \
 638 ({                                                                              \
 639         int __ret = 0;                                                          \
 640         might_sleep();                                                          \
 641         if (!(condition))                                                       \
 642                 __ret = __wait_event_killable_exclusive(wq, condition);         \
 643         __ret;                                                                  \
 644 })
 645
 646
 647 #define __wait_event_freezable_exclusive(wq, condition)                         \
 648         ___wait_event(wq, condition, (TASK_INTERRUPTIBLE|TASK_FREEZABLE), 1, 0,\
 649                         schedule())
 650
 651 #define wait_event_freezable_exclusive(wq, condition)                           \
 652 ({                                                                              \
 653         int __ret = 0;                                                          \
 654         might_sleep();                                                          \
 655         if (!(condition))                                                       \
 656                 __ret = __wait_event_freezable_exclusive(wq, condition);        \
 657         __ret;                                                                  \
 658 })
 659
 660 /**
 661  * wait_event_idle - wait for a condition without contributing to system load
 662  * @wq_head: the waitqueue to wait on
 663  * @condition: a C expression for the event to wait for
 664  *
 665  * The process is put to sleep (TASK_IDLE) until the
 666  * @condition evaluates to true.
 667  * The @condition is checked each time the waitqueue @wq_head is woken up.
 668  *
 669  * wake_up() has to be called after changing any variable that could
 670  * change the result of the wait condition.
 671  *
 672  */
 673 #define wait_event_idle(wq_head, condition)                                     \
 674 do {                                                                            \
 675         might_sleep();                                                          \
 676         if (!(condition))                                                       \
 677                 ___wait_event(wq_head, condition, TASK_IDLE, 0, 0, schedule()); \
 678 } while (0)
 679
 680 /**
 681  * wait_event_idle_exclusive - wait for a condition with contributing to system load
 682  * @wq_head: the waitqueue to wait on
 683  * @condition: a C expression for the event to wait for
 684  *
 685  * The process is put to sleep (TASK_IDLE) until the
 686  * @condition evaluates to true.
 687  * The @condition is checked each time the waitqueue @wq_head is woken up.
 688  *
 689  * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
 690  * set thus if other processes wait on the same list, when this
 691  * process is woken further processes are not considered.
 692  *
 693  * wake_up() has to be called after changing any variable that could
 694  * change the result of the wait condition.
 695  *
 696  */
 697 #define wait_event_idle_exclusive(wq_head, condition)                           \
 698 do {                                                                            \
 699         might_sleep();                                                          \
 700         if (!(condition))                                                       \
 701                 ___wait_event(wq_head, condition, TASK_IDLE, 1, 0, schedule()); \
 702 } while (0)
 703
 704 #define __wait_event_idle_timeout(wq_head, condition, timeout)                  \
 705         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 706                       TASK_IDLE, 0, timeout,                                    \
 707                       __ret = schedule_timeout(__ret))
 708
 709 /**
 710  * wait_event_idle_timeout - sleep without load until a condition becomes true or a timeout elapses
 711  * @wq_head: the waitqueue to wait on
 712  * @condition: a C expression for the event to wait for
 713  * @timeout: timeout, in jiffies
 714  *
 715  * The process is put to sleep (TASK_IDLE) until the
 716  * @condition evaluates to true. The @condition is checked each time
 717  * the waitqueue @wq_head is woken up.
 718  *
 719  * wake_up() has to be called after changing any variable that could
 720  * change the result of the wait condition.
 721  *
 722  * Returns:
 723  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 724  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 725  * or the remaining jiffies (at least 1) if the @condition evaluated
 726  * to %true before the @timeout elapsed.
 727  */
 728 #define wait_event_idle_timeout(wq_head, condition, timeout)                    \
 729 ({                                                                              \
 730         long __ret = timeout;                                                   \
 731         might_sleep();                                                          \
 732         if (!___wait_cond_timeout(condition))                                   \
 733                 __ret = __wait_event_idle_timeout(wq_head, condition, timeout); \
 734         __ret;                                                                  \
 735 })
 736
 737 #define __wait_event_idle_exclusive_timeout(wq_head, condition, timeout)        \
 738         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 739                       TASK_IDLE, 1, timeout,                                    \
 740                       __ret = schedule_timeout(__ret))
 741
 742 /**
 743  * wait_event_idle_exclusive_timeout - sleep without load until a condition becomes true or a timeout elapses
 744  * @wq_head: the waitqueue to wait on
 745  * @condition: a C expression for the event to wait for
 746  * @timeout: timeout, in jiffies
 747  *
 748  * The process is put to sleep (TASK_IDLE) until the
 749  * @condition evaluates to true. The @condition is checked each time
 750  * the waitqueue @wq_head is woken up.
 751  *
 752  * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
 753  * set thus if other processes wait on the same list, when this
 754  * process is woken further processes are not considered.
 755  *
 756  * wake_up() has to be called after changing any variable that could
 757  * change the result of the wait condition.
 758  *
 759  * Returns:
 760  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 761  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 762  * or the remaining jiffies (at least 1) if the @condition evaluated
 763  * to %true before the @timeout elapsed.
 764  */
 765 #define wait_event_idle_exclusive_timeout(wq_head, condition, timeout)          \
 766 ({                                                                              \
 767         long __ret = timeout;                                                   \
 768         might_sleep();                                                          \
 769         if (!___wait_cond_timeout(condition))                                   \
 770                 __ret = __wait_event_idle_exclusive_timeout(wq_head, condition, timeout);\
 771         __ret;                                                                  \
 772 })
 773
 774 extern int do_wait_intr(wait_queue_head_t *, wait_queue_entry_t *);
 775 extern int do_wait_intr_irq(wait_queue_head_t *, wait_queue_entry_t *);
 776
 777 #define __wait_event_interruptible_locked(wq, condition, exclusive, fn)         \
 778 ({                                                                              \
 779         int __ret;                                                              \
 780         DEFINE_WAIT(__wait);                                                    \
 781         if (exclusive)                                                          \
 782                 __wait.flags |= WQ_FLAG_EXCLUSIVE;                              \
 783         do {                                                                    \
 784                 __ret = fn(&(wq), &__wait);                                     \
 785                 if (__ret)                                                      \
 786                         break;                                                  \
 787         } while (!(condition));                                                 \
 788         __remove_wait_queue(&(wq), &__wait);                                    \
 789         __set_current_state(TASK_RUNNING);                                      \
 790         __ret;                                                                  \
 791 })
 792
 793
 794 /**
 795  * wait_event_interruptible_locked - sleep until a condition gets true
 796  * @wq: the waitqueue to wait on
 797  * @condition: a C expression for the event to wait for
 798  *
 799  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 800  * @condition evaluates to true or a signal is received.
 801  * The @condition is checked each time the waitqueue @wq is woken up.
 802  *
 803  * It must be called with wq.lock being held.  This spinlock is
 804  * unlocked while sleeping but @condition testing is done while lock
 805  * is held and when this macro exits the lock is held.
 806  *
 807  * The lock is locked/unlocked using spin_lock()/spin_unlock()
 808  * functions which must match the way they are locked/unlocked outside
 809  * of this macro.
 810  *
 811  * wake_up_locked() has to be called after changing any variable that could
 812  * change the result of the wait condition.
 813  *
 814  * The function will return -ERESTARTSYS if it was interrupted by a
 815  * signal and 0 if @condition evaluated to true.
 816  */
 817 #define wait_event_interruptible_locked(wq, condition)                          \
 818         ((condition)                                                            \
 819          ? 0 : __wait_event_interruptible_locked(wq, condition, 0, do_wait_intr))
 820
 821 /**
 822  * wait_event_interruptible_locked_irq - sleep until a condition gets true
 823  * @wq: the waitqueue to wait on
 824  * @condition: a C expression for the event to wait for
 825  *
 826  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 827  * @condition evaluates to true or a signal is received.
 828  * The @condition is checked each time the waitqueue @wq is woken up.
 829  *
 830  * It must be called with wq.lock being held.  This spinlock is
 831  * unlocked while sleeping but @condition testing is done while lock
 832  * is held and when this macro exits the lock is held.
 833  *
 834  * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
 835  * functions which must match the way they are locked/unlocked outside
 836  * of this macro.
 837  *
 838  * wake_up_locked() has to be called after changing any variable that could
 839  * change the result of the wait condition.
 840  *
 841  * The function will return -ERESTARTSYS if it was interrupted by a
 842  * signal and 0 if @condition evaluated to true.
 843  */
 844 #define wait_event_interruptible_locked_irq(wq, condition)                      \
 845         ((condition)                                                            \
 846          ? 0 : __wait_event_interruptible_locked(wq, condition, 0, do_wait_intr_irq))
 847
 848 /**
 849  * wait_event_interruptible_exclusive_locked - sleep exclusively until a condition gets true
 850  * @wq: the waitqueue to wait on
 851  * @condition: a C expression for the event to wait for
 852  *
 853  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 854  * @condition evaluates to true or a signal is received.
 855  * The @condition is checked each time the waitqueue @wq is woken up.
 856  *
 857  * It must be called with wq.lock being held.  This spinlock is
 858  * unlocked while sleeping but @condition testing is done while lock
 859  * is held and when this macro exits the lock is held.
 860  *
 861  * The lock is locked/unlocked using spin_lock()/spin_unlock()
 862  * functions which must match the way they are locked/unlocked outside
 863  * of this macro.
 864  *
 865  * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
 866  * set thus when other process waits process on the list if this
 867  * process is awaken further processes are not considered.
 868  *
 869  * wake_up_locked() has to be called after changing any variable that could
 870  * change the result of the wait condition.
 871  *
 872  * The function will return -ERESTARTSYS if it was interrupted by a
 873  * signal and 0 if @condition evaluated to true.
 874  */
 875 #define wait_event_interruptible_exclusive_locked(wq, condition)                \
 876         ((condition)                                                            \
 877          ? 0 : __wait_event_interruptible_locked(wq, condition, 1, do_wait_intr))
 878
 879 /**
 880  * wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true
 881  * @wq: the waitqueue to wait on
 882  * @condition: a C expression for the event to wait for
 883  *
 884  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 885  * @condition evaluates to true or a signal is received.
 886  * The @condition is checked each time the waitqueue @wq is woken up.
 887  *
 888  * It must be called with wq.lock being held.  This spinlock is
 889  * unlocked while sleeping but @condition testing is done while lock
 890  * is held and when this macro exits the lock is held.
 891  *
 892  * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
 893  * functions which must match the way they are locked/unlocked outside
 894  * of this macro.
 895  *
 896  * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
 897  * set thus when other process waits process on the list if this
 898  * process is awaken further processes are not considered.
 899  *
 900  * wake_up_locked() has to be called after changing any variable that could
 901  * change the result of the wait condition.
 902  *
 903  * The function will return -ERESTARTSYS if it was interrupted by a
 904  * signal and 0 if @condition evaluated to true.
 905  */
 906 #define wait_event_interruptible_exclusive_locked_irq(wq, condition)            \
 907         ((condition)                                                            \
 908          ? 0 : __wait_event_interruptible_locked(wq, condition, 1, do_wait_intr_irq))
 909
 910
 911 #define __wait_event_killable(wq, condition)                                    \
 912         ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule())
 913
 914 /**
 915  * wait_event_killable - sleep until a condition gets true
 916  * @wq_head: the waitqueue to wait on
 917  * @condition: a C expression for the event to wait for
 918  *
 919  * The process is put to sleep (TASK_KILLABLE) until the
 920  * @condition evaluates to true or a signal is received.
 921  * The @condition is checked each time the waitqueue @wq_head is woken up.
 922  *
 923  * wake_up() has to be called after changing any variable that could
 924  * change the result of the wait condition.
 925  *
 926  * The function will return -ERESTARTSYS if it was interrupted by a
 927  * signal and 0 if @condition evaluated to true.
 928  */
 929 #define wait_event_killable(wq_head, condition)                                 \
 930 ({                                                                              \
 931         int __ret = 0;                                                          \
 932         might_sleep();                                                          \
 933         if (!(condition))                                                       \
 934                 __ret = __wait_event_killable(wq_head, condition);              \
 935         __ret;                                                                  \
 936 })
 937
 938 #define __wait_event_state(wq, condition, state)                                \
 939         ___wait_event(wq, condition, state, 0, 0, schedule())
 940
 941 /**
 942  * wait_event_state - sleep until a condition gets true
 943  * @wq_head: the waitqueue to wait on
 944  * @condition: a C expression for the event to wait for
 945  * @state: state to sleep in
 946  *
 947  * The process is put to sleep (@state) until the @condition evaluates to true
 948  * or a signal is received (when allowed by @state).  The @condition is checked
 949  * each time the waitqueue @wq_head is woken up.
 950  *
 951  * wake_up() has to be called after changing any variable that could
 952  * change the result of the wait condition.
 953  *
 954  * The function will return -ERESTARTSYS if it was interrupted by a signal
 955  * (when allowed by @state) and 0 if @condition evaluated to true.
 956  */
 957 #define wait_event_state(wq_head, condition, state)                             \
 958 ({                                                                              \
 959         int __ret = 0;                                                          \
 960         might_sleep();                                                          \
 961         if (!(condition))                                                       \
 962                 __ret = __wait_event_state(wq_head, condition, state);          \
 963         __ret;                                                                  \
 964 })
 965
 966 #define __wait_event_killable_timeout(wq_head, condition, timeout)              \
 967         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
 968                       TASK_KILLABLE, 0, timeout,                                \
 969                       __ret = schedule_timeout(__ret))
 970
 971 /**
 972  * wait_event_killable_timeout - sleep until a condition gets true or a timeout elapses
 973  * @wq_head: the waitqueue to wait on
 974  * @condition: a C expression for the event to wait for
 975  * @timeout: timeout, in jiffies
 976  *
 977  * The process is put to sleep (TASK_KILLABLE) until the
 978  * @condition evaluates to true or a kill signal is received.
 979  * The @condition is checked each time the waitqueue @wq_head is woken up.
 980  *
 981  * wake_up() has to be called after changing any variable that could
 982  * change the result of the wait condition.
 983  *
 984  * Returns:
 985  * 0 if the @condition evaluated to %false after the @timeout elapsed,
 986  * 1 if the @condition evaluated to %true after the @timeout elapsed,
 987  * the remaining jiffies (at least 1) if the @condition evaluated
 988  * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was
 989  * interrupted by a kill signal.
 990  *
 991  * Only kill signals interrupt this process.
 992  */
 993 #define wait_event_killable_timeout(wq_head, condition, timeout)                \
 994 ({                                                                              \
 995         long __ret = timeout;                                                   \
 996         might_sleep();                                                          \
 997         if (!___wait_cond_timeout(condition))                                   \
 998                 __ret = __wait_event_killable_timeout(wq_head,                  \
 999                                                 condition, timeout);            \
1000         __ret;                                                                  \
1001 })
1002
1003
1004 #define __wait_event_lock_irq(wq_head, condition, lock, cmd)                    \
1005         (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0,     \
1006                             spin_unlock_irq(&lock);                             \
1007                             cmd;                                                \
1008                             schedule();                                         \
1009                             spin_lock_irq(&lock))
1010
1011 /**
1012  * wait_event_lock_irq_cmd - sleep until a condition gets true. The
1013  *                           condition is checked under the lock. This
1014  *                           is expected to be called with the lock
1015  *                           taken.
1016  * @wq_head: the waitqueue to wait on
1017  * @condition: a C expression for the event to wait for
1018  * @lock: a locked spinlock_t, which will be released before cmd
1019  *        and schedule() and reacquired afterwards.
1020  * @cmd: a command which is invoked outside the critical section before
1021  *       sleep
1022  *
1023  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
1024  * @condition evaluates to true. The @condition is checked each time
1025  * the waitqueue @wq_head is woken up.
1026  *
1027  * wake_up() has to be called after changing any variable that could
1028  * change the result of the wait condition.
1029  *
1030  * This is supposed to be called while holding the lock. The lock is
1031  * dropped before invoking the cmd and going to sleep and is reacquired
1032  * afterwards.
1033  */
1034 #define wait_event_lock_irq_cmd(wq_head, condition, lock, cmd)                  \
1035 do {                                                                            \
1036         if (condition)                                                          \
1037                 break;                                                          \
1038         __wait_event_lock_irq(wq_head, condition, lock, cmd);                   \
1039 } while (0)
1040
1041 /**
1042  * wait_event_lock_irq - sleep until a condition gets true. The
1043  *                       condition is checked under the lock. This
1044  *                       is expected to be called with the lock
1045  *                       taken.
1046  * @wq_head: the waitqueue to wait on
1047  * @condition: a C expression for the event to wait for
1048  * @lock: a locked spinlock_t, which will be released before schedule()
1049  *        and reacquired afterwards.
1050  *
1051  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
1052  * @condition evaluates to true. The @condition is checked each time
1053  * the waitqueue @wq_head is woken up.
1054  *
1055  * wake_up() has to be called after changing any variable that could
1056  * change the result of the wait condition.
1057  *
1058  * This is supposed to be called while holding the lock. The lock is
1059  * dropped before going to sleep and is reacquired afterwards.
1060  */
1061 #define wait_event_lock_irq(wq_head, condition, lock)                           \
1062 do {                                                                            \
1063         if (condition)                                                          \
1064                 break;                                                          \
1065         __wait_event_lock_irq(wq_head, condition, lock, );                      \
1066 } while (0)
1067
1068
1069 #define __wait_event_interruptible_lock_irq(wq_head, condition, lock, cmd)      \
1070         ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0,             \
1071                       spin_unlock_irq(&lock);                                   \
1072                       cmd;                                                      \
1073                       schedule();                                               \
1074                       spin_lock_irq(&lock))
1075
1076 /**
1077  * wait_event_interruptible_lock_irq_cmd - sleep until a condition gets true.
1078  *              The condition is checked under the lock. This is expected to
1079  *              be called with the lock taken.
1080  * @wq_head: the waitqueue to wait on
1081  * @condition: a C expression for the event to wait for
1082  * @lock: a locked spinlock_t, which will be released before cmd and
1083  *        schedule() and reacquired afterwards.
1084  * @cmd: a command which is invoked outside the critical section before
1085  *       sleep
1086  *
1087  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1088  * @condition evaluates to true or a signal is received. The @condition is
1089  * checked each time the waitqueue @wq_head is woken up.
1090  *
1091  * wake_up() has to be called after changing any variable that could
1092  * change the result of the wait condition.
1093  *
1094  * This is supposed to be called while holding the lock. The lock is
1095  * dropped before invoking the cmd and going to sleep and is reacquired
1096  * afterwards.
1097  *
1098  * The macro will return -ERESTARTSYS if it was interrupted by a signal
1099  * and 0 if @condition evaluated to true.
1100  */
1101 #define wait_event_interruptible_lock_irq_cmd(wq_head, condition, lock, cmd)    \
1102 ({                                                                              \
1103         int __ret = 0;                                                          \
1104         if (!(condition))                                                       \
1105                 __ret = __wait_event_interruptible_lock_irq(wq_head,            \
1106                                                 condition, lock, cmd);          \
1107         __ret;                                                                  \
1108 })
1109
1110 /**
1111  * wait_event_interruptible_lock_irq - sleep until a condition gets true.
1112  *              The condition is checked under the lock. This is expected
1113  *              to be called with the lock taken.
1114  * @wq_head: the waitqueue to wait on
1115  * @condition: a C expression for the event to wait for
1116  * @lock: a locked spinlock_t, which will be released before schedule()
1117  *        and reacquired afterwards.
1118  *
1119  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1120  * @condition evaluates to true or signal is received. The @condition is
1121  * checked each time the waitqueue @wq_head is woken up.
1122  *
1123  * wake_up() has to be called after changing any variable that could
1124  * change the result of the wait condition.
1125  *
1126  * This is supposed to be called while holding the lock. The lock is
1127  * dropped before going to sleep and is reacquired afterwards.
1128  *
1129  * The macro will return -ERESTARTSYS if it was interrupted by a signal
1130  * and 0 if @condition evaluated to true.
1131  */
1132 #define wait_event_interruptible_lock_irq(wq_head, condition, lock)             \
1133 ({                                                                              \
1134         int __ret = 0;                                                          \
1135         if (!(condition))                                                       \
1136                 __ret = __wait_event_interruptible_lock_irq(wq_head,            \
1137                                                 condition, lock,);              \
1138         __ret;                                                                  \
1139 })
1140
1141 #define __wait_event_lock_irq_timeout(wq_head, condition, lock, timeout, state) \
1142         ___wait_event(wq_head, ___wait_cond_timeout(condition),                 \
1143                       state, 0, timeout,                                        \
1144                       spin_unlock_irq(&lock);                                   \
1145                       __ret = schedule_timeout(__ret);                          \
1146                       spin_lock_irq(&lock));
1147
1148 /**
1149  * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets
1150  *              true or a timeout elapses. The condition is checked under
1151  *              the lock. This is expected to be called with the lock taken.
1152  * @wq_head: the waitqueue to wait on
1153  * @condition: a C expression for the event to wait for
1154  * @lock: a locked spinlock_t, which will be released before schedule()
1155  *        and reacquired afterwards.
1156  * @timeout: timeout, in jiffies
1157  *
1158  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1159  * @condition evaluates to true or signal is received. The @condition is
1160  * checked each time the waitqueue @wq_head is woken up.
1161  *
1162  * wake_up() has to be called after changing any variable that could
1163  * change the result of the wait condition.
1164  *
1165  * This is supposed to be called while holding the lock. The lock is
1166  * dropped before going to sleep and is reacquired afterwards.
1167  *
1168  * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
1169  * was interrupted by a signal, and the remaining jiffies otherwise
1170  * if the condition evaluated to true before the timeout elapsed.
1171  */
1172 #define wait_event_interruptible_lock_irq_timeout(wq_head, condition, lock,     \
1173                                                   timeout)                      \
1174 ({                                                                              \
1175         long __ret = timeout;                                                   \
1176         if (!___wait_cond_timeout(condition))                                   \
1177                 __ret = __wait_event_lock_irq_timeout(                          \
1178                                         wq_head, condition, lock, timeout,      \
1179                                         TASK_INTERRUPTIBLE);                    \
1180         __ret;                                                                  \
1181 })
1182
1183 #define wait_event_lock_irq_timeout(wq_head, condition, lock, timeout)          \
1184 ({                                                                              \
1185         long __ret = timeout;                                                   \
1186         if (!___wait_cond_timeout(condition))                                   \
1187                 __ret = __wait_event_lock_irq_timeout(                          \
1188                                         wq_head, condition, lock, timeout,      \
1189                                         TASK_UNINTERRUPTIBLE);                  \
1190         __ret;                                                                  \
1191 })
1192
1193 /*
1194  * Waitqueues which are removed from the waitqueue_head at wakeup time
1195  */
1196 void prepare_to_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1197 bool prepare_to_wait_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1198 long prepare_to_wait_event(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1199 void finish_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
1200 long wait_woken(struct wait_queue_entry *wq_entry, unsigned mode, long timeout);
1201 int woken_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
1202 int autoremove_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
1203
1204 #define DEFINE_WAIT_FUNC(name, function)                                        \
1205         struct wait_queue_entry name = {                                        \
1206                 .private        = current,                                      \
1207                 .func           = function,                                     \
1208                 .entry          = LIST_HEAD_INIT((name).entry),                 \
1209         }
1210
1211 #define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
1212
1213 #define init_wait(wait)                                                         \
1214         do {                                                                    \
1215                 (wait)->private = current;                                      \
1216                 (wait)->func = autoremove_wake_function;                        \
1217                 INIT_LIST_HEAD(&(wait)->entry);                                 \
1218                 (wait)->flags = 0;                                              \
1219         } while (0)
1220
1221 typedef int (*task_call_f)(struct task_struct *p, void *arg);
1222 extern int task_call_func(struct task_struct *p, task_call_f func, void *arg);
1223
1224 #endif /* _LINUX_WAIT_H */