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TOMOYO Linux Cross Reference
Linux/include/linux/interrupt.h

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

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