include/linux/interrupt.h

   1 /* interrupt.h */
   2 #ifndef _LINUX_INTERRUPT_H
   3 #define _LINUX_INTERRUPT_H
   4
   5 #include <linux/kernel.h>
   6 #include <linux/linkage.h>
   7 #include <linux/bitops.h>
   8 #include <linux/preempt.h>
   9 #include <linux/cpumask.h>
  10 #include <linux/irqreturn.h>
  11 #include <linux/irqnr.h>
  12 #include <linux/hardirq.h>
  13 #include <linux/irqflags.h>
  14 #include <linux/hrtimer.h>
  15 #include <linux/kref.h>
  16 #include <linux/workqueue.h>
  17
  18 #include <linux/atomic.h>
  19 #include <asm/ptrace.h>
  20
  21 /*
  22  * These correspond to the IORESOURCE_IRQ_* defines in
  23  * linux/ioport.h to select the interrupt line behaviour.  When
  24  * requesting an interrupt without specifying a IRQF_TRIGGER, the
  25  * setting should be assumed to be "as already configured", which
  26  * may be as per machine or firmware initialisation.
  27  */
  28 #define IRQF_TRIGGER_NONE       0x00000000
  29 #define IRQF_TRIGGER_RISING     0x00000001
  30 #define IRQF_TRIGGER_FALLING    0x00000002
  31 #define IRQF_TRIGGER_HIGH       0x00000004
  32 #define IRQF_TRIGGER_LOW        0x00000008
  33 #define IRQF_TRIGGER_MASK       (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
  34                                  IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
  35 #define IRQF_TRIGGER_PROBE      0x00000010
  36
  37 /*
  38  * These flags used only by the kernel as part of the
  39  * irq handling routines.
  40  *
  41  * IRQF_DISABLED - keep irqs disabled when calling the action handler.
  42  *                 DEPRECATED. This flag is a NOOP and scheduled to be removed
  43  * IRQF_SHARED - allow sharing the irq among several devices
  44  * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
  45  * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
  46  * IRQF_PERCPU - Interrupt is per cpu
  47  * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
  48  * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
  49  *                registered first in an shared interrupt is considered for
  50  *                performance reasons)
  51  * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
  52  *                Used by threaded interrupts which need to keep the
  53  *                irq line disabled until the threaded handler has been run.
  54  * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend
  55  * IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set
  56  * IRQF_NO_THREAD - Interrupt cannot be threaded
  57  * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device
  58  *                resume time.
  59  */
  60 #define IRQF_DISABLED           0x00000020
  61 #define IRQF_SHARED             0x00000080
  62 #define IRQF_PROBE_SHARED       0x00000100
  63 #define __IRQF_TIMER            0x00000200
  64 #define IRQF_PERCPU             0x00000400
  65 #define IRQF_NOBALANCING        0x00000800
  66 #define IRQF_IRQPOLL            0x00001000
  67 #define IRQF_ONESHOT            0x00002000
  68 #define IRQF_NO_SUSPEND         0x00004000
  69 #define IRQF_FORCE_RESUME       0x00008000
  70 #define IRQF_NO_THREAD          0x00010000
  71 #define IRQF_EARLY_RESUME       0x00020000
  72
  73 #define IRQF_TIMER              (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
  74
  75 /*
  76  * These values can be returned by request_any_context_irq() and
  77  * describe the context the interrupt will be run in.
  78  *
  79  * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
  80  * IRQC_IS_NESTED - interrupt runs in a nested threaded context
  81  */
  82 enum {
  83         IRQC_IS_HARDIRQ = 0,
  84         IRQC_IS_NESTED,
  85 };
  86
  87 typedef irqreturn_t (*irq_handler_t)(int, void *);
  88
  89 /**
  90  * struct irqaction - per interrupt action descriptor
  91  * @handler:    interrupt handler function
  92  * @name:       name of the device
  93  * @dev_id:     cookie to identify the device
  94  * @percpu_dev_id:      cookie to identify the device
  95  * @next:       pointer to the next irqaction for shared interrupts
  96  * @irq:        interrupt number
  97  * @flags:      flags (see IRQF_* above)
  98  * @thread_fn:  interrupt handler function for threaded interrupts
  99  * @thread:     thread pointer for threaded interrupts
 100  * @thread_flags:       flags related to @thread
 101  * @thread_mask:        bitmask for keeping track of @thread activity
 102  * @dir:        pointer to the proc/irq/NN/name entry
 103  */
 104 struct irqaction {
 105         irq_handler_t           handler;
 106         void                    *dev_id;
 107         void __percpu           *percpu_dev_id;
 108         struct irqaction        *next;
 109         irq_handler_t           thread_fn;
 110         struct task_struct      *thread;
 111         unsigned int            irq;
 112         unsigned int            flags;
 113         unsigned long           thread_flags;
 114         unsigned long           thread_mask;
 115         const char              *name;
 116 #ifdef CONFIG_MTPROF_IRQ_DURATION
 117         unsigned long long duration;
 118         unsigned long count;
 119         unsigned long long dur_max;
 120         unsigned long long dur_min;
 121 #endif
 122         struct proc_dir_entry   *dir;
 123 } ____cacheline_internodealigned_in_smp;
 124
 125 extern irqreturn_t no_action(int cpl, void *dev_id);
 126
 127 #ifdef CONFIG_GENERIC_HARDIRQS
 128 extern int __must_check
 129 request_threaded_irq(unsigned int irq, irq_handler_t handler,
 130                      irq_handler_t thread_fn,
 131                      unsigned long flags, const char *name, void *dev);
 132
 133 static inline int __must_check
 134 request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
 135             const char *name, void *dev)
 136 {
 137         return request_threaded_irq(irq, handler, NULL, flags, name, dev);
 138 }
 139
 140 extern int __must_check
 141 request_any_context_irq(unsigned int irq, irq_handler_t handler,
 142                         unsigned long flags, const char *name, void *dev_id);
 143
 144 extern int __must_check
 145 request_percpu_irq(unsigned int irq, irq_handler_t handler,
 146                    const char *devname, void __percpu *percpu_dev_id);
 147 #else
 148
 149 extern int __must_check
 150 request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
 151             const char *name, void *dev);
 152
 153 /*
 154  * Special function to avoid ifdeffery in kernel/irq/devres.c which
 155  * gets magically built by GENERIC_HARDIRQS=n architectures (sparc,
 156  * m68k). I really love these $@%#!* obvious Makefile references:
 157  * ../../../kernel/irq/devres.o
 158  */
 159 static inline int __must_check
 160 request_threaded_irq(unsigned int irq, irq_handler_t handler,
 161                      irq_handler_t thread_fn,
 162                      unsigned long flags, const char *name, void *dev)
 163 {
 164         return request_irq(irq, handler, flags, name, dev);
 165 }
 166
 167 static inline int __must_check
 168 request_any_context_irq(unsigned int irq, irq_handler_t handler,
 169                         unsigned long flags, const char *name, void *dev_id)
 170 {
 171         return request_irq(irq, handler, flags, name, dev_id);
 172 }
 173
 174 static inline int __must_check
 175 request_percpu_irq(unsigned int irq, irq_handler_t handler,
 176                    const char *devname, void __percpu *percpu_dev_id)
 177 {
 178         return request_irq(irq, handler, 0, devname, percpu_dev_id);
 179 }
 180 #endif
 181
 182 extern void free_irq(unsigned int, void *);
 183 extern void free_percpu_irq(unsigned int, void __percpu *);
 184
 185 struct device;
 186
 187 extern int __must_check
 188 devm_request_threaded_irq(struct device *dev, unsigned int irq,
 189                           irq_handler_t handler, irq_handler_t thread_fn,
 190                           unsigned long irqflags, const char *devname,
 191                           void *dev_id);
 192
 193 static inline int __must_check
 194 devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
 195                  unsigned long irqflags, const char *devname, void *dev_id)
 196 {
 197         return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
 198                                          devname, dev_id);
 199 }
 200
 201 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
 202
 203 /*
 204  * On lockdep we dont want to enable hardirqs in hardirq
 205  * context. Use local_irq_enable_in_hardirq() to annotate
 206  * kernel code that has to do this nevertheless (pretty much
 207  * the only valid case is for old/broken hardware that is
 208  * insanely slow).
 209  *
 210  * NOTE: in theory this might break fragile code that relies
 211  * on hardirq delivery - in practice we dont seem to have such
 212  * places left. So the only effect should be slightly increased
 213  * irqs-off latencies.
 214  */
 215 #ifdef CONFIG_LOCKDEP
 216 # define local_irq_enable_in_hardirq()  do { } while (0)
 217 #else
 218 # define local_irq_enable_in_hardirq()  local_irq_enable()
 219 #endif
 220
 221 extern void disable_irq_nosync(unsigned int irq);
 222 extern void disable_irq(unsigned int irq);
 223 extern void disable_percpu_irq(unsigned int irq);
 224 extern void enable_irq(unsigned int irq);
 225 extern void enable_percpu_irq(unsigned int irq, unsigned int type);
 226
 227 /* The following three functions are for the core kernel use only. */
 228 #ifdef CONFIG_GENERIC_HARDIRQS
 229 extern void suspend_device_irqs(void);
 230 extern void resume_device_irqs(void);
 231 #ifdef CONFIG_PM_SLEEP
 232 extern int check_wakeup_irqs(void);
 233 #else
 234 static inline int check_wakeup_irqs(void) { return 0; }
 235 #endif
 236 #else
 237 static inline void suspend_device_irqs(void) { };
 238 static inline void resume_device_irqs(void) { };
 239 static inline int check_wakeup_irqs(void) { return 0; }
 240 #endif
 241
 242 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
 243
 244 extern cpumask_var_t irq_default_affinity;
 245
 246 /* Internal implementation. Use the helpers below */
 247 extern int __irq_set_affinity(unsigned int irq, const struct cpumask *cpumask,
 248                               bool force);
 249
 250 /**
 251  * irq_set_affinity - Set the irq affinity of a given irq
 252  * @irq:        Interrupt to set affinity
 253  * @mask:       cpumask
 254  *
 255  * Fails if cpumask does not contain an online CPU
 256  */
 257 static inline int
 258 irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
 259 {
 260         return __irq_set_affinity(irq, cpumask, false);
 261 }
 262
 263 /**
 264  * irq_force_affinity - Force the irq affinity of a given irq
 265  * @irq:        Interrupt to set affinity
 266  * @mask:       cpumask
 267  *
 268  * Same as irq_set_affinity, but without checking the mask against
 269  * online cpus.
 270  *
 271  * Solely for low level cpu hotplug code, where we need to make per
 272  * cpu interrupts affine before the cpu becomes online.
 273  */
 274 static inline int
 275 irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
 276 {
 277         return __irq_set_affinity(irq, cpumask, true);
 278 }
 279
 280 extern int irq_can_set_affinity(unsigned int irq);
 281 extern int irq_select_affinity(unsigned int irq);
 282
 283 extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
 284
 285 /**
 286  * struct irq_affinity_notify - context for notification of IRQ affinity changes
 287  * @irq:                Interrupt to which notification applies
 288  * @kref:               Reference count, for internal use
 289  * @work:               Work item, for internal use
 290  * @notify:             Function to be called on change.  This will be
 291  *                      called in process context.
 292  * @release:            Function to be called on release.  This will be
 293  *                      called in process context.  Once registered, the
 294  *                      structure must only be freed when this function is
 295  *                      called or later.
 296  */
 297 struct irq_affinity_notify {
 298         unsigned int irq;
 299         struct kref kref;
 300         struct work_struct work;
 301         void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
 302         void (*release)(struct kref *ref);
 303 };
 304
 305 extern int
 306 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
 307
 308 #else /* CONFIG_SMP */
 309
 310 static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
 311 {
 312         return -EINVAL;
 313 }
 314
 315 static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
 316 {
 317         return 0;
 318 }
 319
 320 static inline int irq_can_set_affinity(unsigned int irq)
 321 {
 322         return 0;
 323 }
 324
 325 static inline int irq_select_affinity(unsigned int irq)  { return 0; }
 326
 327 static inline int irq_set_affinity_hint(unsigned int irq,
 328                                         const struct cpumask *m)
 329 {
 330         return -EINVAL;
 331 }
 332 #endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
 333
 334 #ifdef CONFIG_GENERIC_HARDIRQS
 335 /*
 336  * Special lockdep variants of irq disabling/enabling.
 337  * These should be used for locking constructs that
 338  * know that a particular irq context which is disabled,
 339  * and which is the only irq-context user of a lock,
 340  * that it's safe to take the lock in the irq-disabled
 341  * section without disabling hardirqs.
 342  *
 343  * On !CONFIG_LOCKDEP they are equivalent to the normal
 344  * irq disable/enable methods.
 345  */
 346 static inline void disable_irq_nosync_lockdep(unsigned int irq)
 347 {
 348         disable_irq_nosync(irq);
 349 #ifdef CONFIG_LOCKDEP
 350         local_irq_disable();
 351 #endif
 352 }
 353
 354 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
 355 {
 356         disable_irq_nosync(irq);
 357 #ifdef CONFIG_LOCKDEP
 358         local_irq_save(*flags);
 359 #endif
 360 }
 361
 362 static inline void disable_irq_lockdep(unsigned int irq)
 363 {
 364         disable_irq(irq);
 365 #ifdef CONFIG_LOCKDEP
 366         local_irq_disable();
 367 #endif
 368 }
 369
 370 static inline void enable_irq_lockdep(unsigned int irq)
 371 {
 372 #ifdef CONFIG_LOCKDEP
 373         local_irq_enable();
 374 #endif
 375         enable_irq(irq);
 376 }
 377
 378 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
 379 {
 380 #ifdef CONFIG_LOCKDEP
 381         local_irq_restore(*flags);
 382 #endif
 383         enable_irq(irq);
 384 }
 385
 386 /* IRQ wakeup (PM) control: */
 387 extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
 388
 389 static inline int enable_irq_wake(unsigned int irq)
 390 {
 391         return irq_set_irq_wake(irq, 1);
 392 }
 393
 394 static inline int disable_irq_wake(unsigned int irq)
 395 {
 396         return irq_set_irq_wake(irq, 0);
 397 }
 398
 399 #else /* !CONFIG_GENERIC_HARDIRQS */
 400 /*
 401  * NOTE: non-genirq architectures, if they want to support the lock
 402  * validator need to define the methods below in their asm/irq.h
 403  * files, under an #ifdef CONFIG_LOCKDEP section.
 404  */
 405 #ifndef CONFIG_LOCKDEP
 406 #  define disable_irq_nosync_lockdep(irq)       disable_irq_nosync(irq)
 407 #  define disable_irq_nosync_lockdep_irqsave(irq, flags) \
 408                                                 disable_irq_nosync(irq)
 409 #  define disable_irq_lockdep(irq)              disable_irq(irq)
 410 #  define enable_irq_lockdep(irq)               enable_irq(irq)
 411 #  define enable_irq_lockdep_irqrestore(irq, flags) \
 412                                                 enable_irq(irq)
 413 # endif
 414
 415 static inline int enable_irq_wake(unsigned int irq)
 416 {
 417         return 0;
 418 }
 419
 420 static inline int disable_irq_wake(unsigned int irq)
 421 {
 422         return 0;
 423 }
 424 #endif /* CONFIG_GENERIC_HARDIRQS */
 425
 426
 427 #ifdef CONFIG_IRQ_FORCED_THREADING
 428 extern bool force_irqthreads;
 429 #else
 430 #define force_irqthreads        (0)
 431 #endif
 432
 433 #ifndef __ARCH_SET_SOFTIRQ_PENDING
 434 #define set_softirq_pending(x) (local_softirq_pending() = (x))
 435 #define or_softirq_pending(x)  (local_softirq_pending() |= (x))
 436 #endif
 437
 438 /* Some architectures might implement lazy enabling/disabling of
 439  * interrupts. In some cases, such as stop_machine, we might want
 440  * to ensure that after a local_irq_disable(), interrupts have
 441  * really been disabled in hardware. Such architectures need to
 442  * implement the following hook.
 443  */
 444 #ifndef hard_irq_disable
 445 #define hard_irq_disable()      do { } while(0)
 446 #endif
 447
 448 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
 449    frequency threaded job scheduling. For almost all the purposes
 450    tasklets are more than enough. F.e. all serial device BHs et
 451    al. should be converted to tasklets, not to softirqs.
 452  */
 453
 454 enum
 455 {
 456         HI_SOFTIRQ=0,
 457         TIMER_SOFTIRQ,
 458         NET_TX_SOFTIRQ,
 459         NET_RX_SOFTIRQ,
 460         BLOCK_SOFTIRQ,
 461         BLOCK_IOPOLL_SOFTIRQ,
 462         TASKLET_SOFTIRQ,
 463         SCHED_SOFTIRQ,
 464         HRTIMER_SOFTIRQ,
 465         RCU_SOFTIRQ,    /* Preferable RCU should always be the last softirq */
 466
 467         NR_SOFTIRQS
 468 };
 469
 470 #define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ))
 471
 472 /* map softirq index to softirq name. update 'softirq_to_name' in
 473  * kernel/softirq.c when adding a new softirq.
 474  */
 475 extern char *softirq_to_name[NR_SOFTIRQS];
 476
 477 /* softirq mask and active fields moved to irq_cpustat_t in
 478  * asm/hardirq.h to get better cache usage.  KAO
 479  */
 480
 481 struct softirq_action
 482 {
 483         void    (*action)(struct softirq_action *);
 484 };
 485
 486 asmlinkage void do_softirq(void);
 487 asmlinkage void __do_softirq(void);
 488 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
 489 extern void softirq_init(void);
 490 extern void __raise_softirq_irqoff(unsigned int nr);
 491
 492 extern void raise_softirq_irqoff(unsigned int nr);
 493 extern void raise_softirq(unsigned int nr);
 494
 495 DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
 496
 497 static inline struct task_struct *this_cpu_ksoftirqd(void)
 498 {
 499         return this_cpu_read(ksoftirqd);
 500 }
 501
 502 /* Tasklets --- multithreaded analogue of BHs.
 503
 504    Main feature differing them of generic softirqs: tasklet
 505    is running only on one CPU simultaneously.
 506
 507    Main feature differing them of BHs: different tasklets
 508    may be run simultaneously on different CPUs.
 509
 510    Properties:
 511    * If tasklet_schedule() is called, then tasklet is guaranteed
 512      to be executed on some cpu at least once after this.
 513    * If the tasklet is already scheduled, but its execution is still not
 514      started, it will be executed only once.
 515    * If this tasklet is already running on another CPU (or schedule is called
 516      from tasklet itself), it is rescheduled for later.
 517    * Tasklet is strictly serialized wrt itself, but not
 518      wrt another tasklets. If client needs some intertask synchronization,
 519      he makes it with spinlocks.
 520  */
 521
 522 struct tasklet_struct
 523 {
 524         struct tasklet_struct *next;
 525         unsigned long state;
 526         atomic_t count;
 527         void (*func)(unsigned long);
 528         unsigned long data;
 529 };
 530
 531 #define DECLARE_TASKLET(name, func, data) \
 532 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
 533
 534 #define DECLARE_TASKLET_DISABLED(name, func, data) \
 535 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
 536
 537
 538 enum
 539 {
 540         TASKLET_STATE_SCHED,    /* Tasklet is scheduled for execution */
 541         TASKLET_STATE_RUN       /* Tasklet is running (SMP only) */
 542 };
 543
 544 #ifdef CONFIG_SMP
 545 static inline int tasklet_trylock(struct tasklet_struct *t)
 546 {
 547         return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
 548 }
 549
 550 static inline void tasklet_unlock(struct tasklet_struct *t)
 551 {
 552         smp_mb__before_clear_bit();
 553         clear_bit(TASKLET_STATE_RUN, &(t)->state);
 554 }
 555
 556 static inline void tasklet_unlock_wait(struct tasklet_struct *t)
 557 {
 558         while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
 559 }
 560 #else
 561 #define tasklet_trylock(t) 1
 562 #define tasklet_unlock_wait(t) do { } while (0)
 563 #define tasklet_unlock(t) do { } while (0)
 564 #endif
 565
 566 extern void __tasklet_schedule(struct tasklet_struct *t);
 567
 568 static inline void tasklet_schedule(struct tasklet_struct *t)
 569 {
 570         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 571                 __tasklet_schedule(t);
 572 }
 573
 574 extern void __tasklet_hi_schedule(struct tasklet_struct *t);
 575
 576 static inline void tasklet_hi_schedule(struct tasklet_struct *t)
 577 {
 578         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 579                 __tasklet_hi_schedule(t);
 580 }
 581
 582 extern void __tasklet_hi_schedule_first(struct tasklet_struct *t);
 583
 584 /*
 585  * This version avoids touching any other tasklets. Needed for kmemcheck
 586  * in order not to take any page faults while enqueueing this tasklet;
 587  * consider VERY carefully whether you really need this or
 588  * tasklet_hi_schedule()...
 589  */
 590 static inline void tasklet_hi_schedule_first(struct tasklet_struct *t)
 591 {
 592         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 593                 __tasklet_hi_schedule_first(t);
 594 }
 595
 596
 597 static inline void tasklet_disable_nosync(struct tasklet_struct *t)
 598 {
 599         atomic_inc(&t->count);
 600         smp_mb__after_atomic_inc();
 601 }
 602
 603 static inline void tasklet_disable(struct tasklet_struct *t)
 604 {
 605         tasklet_disable_nosync(t);
 606         tasklet_unlock_wait(t);
 607         smp_mb();
 608 }
 609
 610 static inline void tasklet_enable(struct tasklet_struct *t)
 611 {
 612         smp_mb__before_atomic_dec();
 613         atomic_dec(&t->count);
 614 }
 615
 616 static inline void tasklet_hi_enable(struct tasklet_struct *t)
 617 {
 618         smp_mb__before_atomic_dec();
 619         atomic_dec(&t->count);
 620 }
 621
 622 extern void tasklet_kill(struct tasklet_struct *t);
 623 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
 624 extern void tasklet_init(struct tasklet_struct *t,
 625                          void (*func)(unsigned long), unsigned long data);
 626
 627 struct tasklet_hrtimer {
 628         struct hrtimer          timer;
 629         struct tasklet_struct   tasklet;
 630         enum hrtimer_restart    (*function)(struct hrtimer *);
 631 };
 632
 633 extern void
 634 tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer,
 635                      enum hrtimer_restart (*function)(struct hrtimer *),
 636                      clockid_t which_clock, enum hrtimer_mode mode);
 637
 638 static inline
 639 int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time,
 640                           const enum hrtimer_mode mode)
 641 {
 642         return hrtimer_start(&ttimer->timer, time, mode);
 643 }
 644
 645 static inline
 646 void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
 647 {
 648         hrtimer_cancel(&ttimer->timer);
 649         tasklet_kill(&ttimer->tasklet);
 650 }
 651
 652 /*
 653  * Autoprobing for irqs:
 654  *
 655  * probe_irq_on() and probe_irq_off() provide robust primitives
 656  * for accurate IRQ probing during kernel initialization.  They are
 657  * reasonably simple to use, are not "fooled" by spurious interrupts,
 658  * and, unlike other attempts at IRQ probing, they do not get hung on
 659  * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
 660  *
 661  * For reasonably foolproof probing, use them as follows:
 662  *
 663  * 1. clear and/or mask the device's internal interrupt.
 664  * 2. sti();
 665  * 3. irqs = probe_irq_on();      // "take over" all unassigned idle IRQs
 666  * 4. enable the device and cause it to trigger an interrupt.
 667  * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
 668  * 6. irq = probe_irq_off(irqs);  // get IRQ number, 0=none, negative=multiple
 669  * 7. service the device to clear its pending interrupt.
 670  * 8. loop again if paranoia is required.
 671  *
 672  * probe_irq_on() returns a mask of allocated irq's.
 673  *
 674  * probe_irq_off() takes the mask as a parameter,
 675  * and returns the irq number which occurred,
 676  * or zero if none occurred, or a negative irq number
 677  * if more than one irq occurred.
 678  */
 679
 680 #if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
 681 static inline unsigned long probe_irq_on(void)
 682 {
 683         return 0;
 684 }
 685 static inline int probe_irq_off(unsigned long val)
 686 {
 687         return 0;
 688 }
 689 static inline unsigned int probe_irq_mask(unsigned long val)
 690 {
 691         return 0;
 692 }
 693 #else
 694 extern unsigned long probe_irq_on(void);        /* returns 0 on failure */
 695 extern int probe_irq_off(unsigned long);        /* returns 0 or negative on failure */
 696 extern unsigned int probe_irq_mask(unsigned long);      /* returns mask of ISA interrupts */
 697 #endif
 698
 699 #ifdef CONFIG_PROC_FS
 700 /* Initialize /proc/irq/ */
 701 extern void init_irq_proc(void);
 702 #else
 703 static inline void init_irq_proc(void)
 704 {
 705 }
 706 #endif
 707
 708 struct seq_file;
 709 int show_interrupts(struct seq_file *p, void *v);
 710 int arch_show_interrupts(struct seq_file *p, int prec);
 711
 712 extern int early_irq_init(void);
 713 extern int arch_probe_nr_irqs(void);
 714 extern int arch_early_irq_init(void);
 715
 716 #endif