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/sched.h>
  14 #include <linux/irqflags.h>
  15 #include <linux/smp.h>
  16 #include <linux/percpu.h>
  17 #include <linux/hrtimer.h>
  18
  19 #include <asm/atomic.h>
  20 #include <asm/ptrace.h>
  21 #include <asm/system.h>
  22
  23 /*
  24  * These correspond to the IORESOURCE_IRQ_* defines in
  25  * linux/ioport.h to select the interrupt line behaviour.  When
  26  * requesting an interrupt without specifying a IRQF_TRIGGER, the
  27  * setting should be assumed to be "as already configured", which
  28  * may be as per machine or firmware initialisation.
  29  */
  30 #define IRQF_TRIGGER_NONE       0x00000000
  31 #define IRQF_TRIGGER_RISING     0x00000001
  32 #define IRQF_TRIGGER_FALLING    0x00000002
  33 #define IRQF_TRIGGER_HIGH       0x00000004
  34 #define IRQF_TRIGGER_LOW        0x00000008
  35 #define IRQF_TRIGGER_MASK       (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
  36                                  IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
  37 #define IRQF_TRIGGER_PROBE      0x00000010
  38
  39 /*
  40  * These flags used only by the kernel as part of the
  41  * irq handling routines.
  42  *
  43  * IRQF_DISABLED - keep irqs disabled when calling the action handler
  44  * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
  45  * IRQF_SHARED - allow sharing the irq among several devices
  46  * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
  47  * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
  48  * IRQF_PERCPU - Interrupt is per cpu
  49  * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
  50  * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
  51  *                registered first in an shared interrupt is considered for
  52  *                performance reasons)
  53  * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
  54  *                Used by threaded interrupts which need to keep the
  55  *                irq line disabled until the threaded handler has been run.
  56  */
  57 #define IRQF_DISABLED           0x00000020
  58 #define IRQF_SAMPLE_RANDOM      0x00000040
  59 #define IRQF_SHARED             0x00000080
  60 #define IRQF_PROBE_SHARED       0x00000100
  61 #define IRQF_TIMER              0x00000200
  62 #define IRQF_PERCPU             0x00000400
  63 #define IRQF_NOBALANCING        0x00000800
  64 #define IRQF_IRQPOLL            0x00001000
  65 #define IRQF_ONESHOT            0x00002000
  66
  67 /*
  68  * Bits used by threaded handlers:
  69  * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run
  70  * IRQTF_DIED      - handler thread died
  71  * IRQTF_WARNED    - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed
  72  * IRQTF_AFFINITY  - irq thread is requested to adjust affinity
  73  */
  74 enum {
  75         IRQTF_RUNTHREAD,
  76         IRQTF_DIED,
  77         IRQTF_WARNED,
  78         IRQTF_AFFINITY,
  79 };
  80
  81 typedef irqreturn_t (*irq_handler_t)(int, void *);
  82
  83 /**
  84  * struct irqaction - per interrupt action descriptor
  85  * @handler:    interrupt handler function
  86  * @flags:      flags (see IRQF_* above)
  87  * @mask:       no comment as it is useless and about to be removed
  88  * @name:       name of the device
  89  * @dev_id:     cookie to identify the device
  90  * @next:       pointer to the next irqaction for shared interrupts
  91  * @irq:        interrupt number
  92  * @dir:        pointer to the proc/irq/NN/name entry
  93  * @thread_fn:  interupt handler function for threaded interrupts
  94  * @thread:     thread pointer for threaded interrupts
  95  * @thread_flags:       flags related to @thread
  96  */
  97 struct irqaction {
  98         irq_handler_t handler;
  99         unsigned long flags;
 100         cpumask_t mask;
 101         const char *name;
 102         void *dev_id;
 103         struct irqaction *next;
 104         int irq;
 105         struct proc_dir_entry *dir;
 106         irq_handler_t thread_fn;
 107         struct task_struct *thread;
 108         unsigned long thread_flags;
 109 };
 110
 111 extern irqreturn_t no_action(int cpl, void *dev_id);
 112
 113 #ifdef CONFIG_GENERIC_HARDIRQS
 114 extern int __must_check
 115 request_threaded_irq(unsigned int irq, irq_handler_t handler,
 116                      irq_handler_t thread_fn,
 117                      unsigned long flags, const char *name, void *dev);
 118
 119 static inline int __must_check
 120 request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
 121             const char *name, void *dev)
 122 {
 123         return request_threaded_irq(irq, handler, NULL, flags, name, dev);
 124 }
 125
 126 extern void exit_irq_thread(void);
 127 #else
 128
 129 extern int __must_check
 130 request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
 131             const char *name, void *dev);
 132
 133 /*
 134  * Special function to avoid ifdeffery in kernel/irq/devres.c which
 135  * gets magically built by GENERIC_HARDIRQS=n architectures (sparc,
 136  * m68k). I really love these $@%#!* obvious Makefile references:
 137  * ../../../kernel/irq/devres.o
 138  */
 139 static inline int __must_check
 140 request_threaded_irq(unsigned int irq, irq_handler_t handler,
 141                      irq_handler_t thread_fn,
 142                      unsigned long flags, const char *name, void *dev)
 143 {
 144         return request_irq(irq, handler, flags, name, dev);
 145 }
 146
 147 static inline void exit_irq_thread(void) { }
 148 #endif
 149
 150 extern void free_irq(unsigned int, void *);
 151
 152 struct device;
 153
 154 extern int __must_check
 155 devm_request_threaded_irq(struct device *dev, unsigned int irq,
 156                           irq_handler_t handler, irq_handler_t thread_fn,
 157                           unsigned long irqflags, const char *devname,
 158                           void *dev_id);
 159
 160 static inline int __must_check
 161 devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
 162                  unsigned long irqflags, const char *devname, void *dev_id)
 163 {
 164         return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
 165                                          devname, dev_id);
 166 }
 167
 168 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
 169
 170 /*
 171  * On lockdep we dont want to enable hardirqs in hardirq
 172  * context. Use local_irq_enable_in_hardirq() to annotate
 173  * kernel code that has to do this nevertheless (pretty much
 174  * the only valid case is for old/broken hardware that is
 175  * insanely slow).
 176  *
 177  * NOTE: in theory this might break fragile code that relies
 178  * on hardirq delivery - in practice we dont seem to have such
 179  * places left. So the only effect should be slightly increased
 180  * irqs-off latencies.
 181  */
 182 #ifdef CONFIG_LOCKDEP
 183 # define local_irq_enable_in_hardirq()  do { } while (0)
 184 #else
 185 # define local_irq_enable_in_hardirq()  local_irq_enable()
 186 #endif
 187
 188 extern void disable_irq_nosync(unsigned int irq);
 189 extern void disable_irq(unsigned int irq);
 190 extern void enable_irq(unsigned int irq);
 191
 192 /* The following three functions are for the core kernel use only. */
 193 #ifdef CONFIG_GENERIC_HARDIRQS
 194 extern void suspend_device_irqs(void);
 195 extern void resume_device_irqs(void);
 196 #ifdef CONFIG_PM_SLEEP
 197 extern int check_wakeup_irqs(void);
 198 #else
 199 static inline int check_wakeup_irqs(void) { return 0; }
 200 #endif
 201 #else
 202 static inline void suspend_device_irqs(void) { };
 203 static inline void resume_device_irqs(void) { };
 204 static inline int check_wakeup_irqs(void) { return 0; }
 205 #endif
 206
 207 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
 208
 209 extern cpumask_var_t irq_default_affinity;
 210
 211 extern int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask);
 212 extern int irq_can_set_affinity(unsigned int irq);
 213 extern int irq_select_affinity(unsigned int irq);
 214
 215 #else /* CONFIG_SMP */
 216
 217 static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
 218 {
 219         return -EINVAL;
 220 }
 221
 222 static inline int irq_can_set_affinity(unsigned int irq)
 223 {
 224         return 0;
 225 }
 226
 227 static inline int irq_select_affinity(unsigned int irq)  { return 0; }
 228
 229 #endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
 230
 231 #ifdef CONFIG_GENERIC_HARDIRQS
 232 /*
 233  * Special lockdep variants of irq disabling/enabling.
 234  * These should be used for locking constructs that
 235  * know that a particular irq context which is disabled,
 236  * and which is the only irq-context user of a lock,
 237  * that it's safe to take the lock in the irq-disabled
 238  * section without disabling hardirqs.
 239  *
 240  * On !CONFIG_LOCKDEP they are equivalent to the normal
 241  * irq disable/enable methods.
 242  */
 243 static inline void disable_irq_nosync_lockdep(unsigned int irq)
 244 {
 245         disable_irq_nosync(irq);
 246 #ifdef CONFIG_LOCKDEP
 247         local_irq_disable();
 248 #endif
 249 }
 250
 251 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
 252 {
 253         disable_irq_nosync(irq);
 254 #ifdef CONFIG_LOCKDEP
 255         local_irq_save(*flags);
 256 #endif
 257 }
 258
 259 static inline void disable_irq_lockdep(unsigned int irq)
 260 {
 261         disable_irq(irq);
 262 #ifdef CONFIG_LOCKDEP
 263         local_irq_disable();
 264 #endif
 265 }
 266
 267 static inline void enable_irq_lockdep(unsigned int irq)
 268 {
 269 #ifdef CONFIG_LOCKDEP
 270         local_irq_enable();
 271 #endif
 272         enable_irq(irq);
 273 }
 274
 275 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
 276 {
 277 #ifdef CONFIG_LOCKDEP
 278         local_irq_restore(*flags);
 279 #endif
 280         enable_irq(irq);
 281 }
 282
 283 /* IRQ wakeup (PM) control: */
 284 extern int set_irq_wake(unsigned int irq, unsigned int on);
 285
 286 static inline int enable_irq_wake(unsigned int irq)
 287 {
 288         return set_irq_wake(irq, 1);
 289 }
 290
 291 static inline int disable_irq_wake(unsigned int irq)
 292 {
 293         return set_irq_wake(irq, 0);
 294 }
 295
 296 #else /* !CONFIG_GENERIC_HARDIRQS */
 297 /*
 298  * NOTE: non-genirq architectures, if they want to support the lock
 299  * validator need to define the methods below in their asm/irq.h
 300  * files, under an #ifdef CONFIG_LOCKDEP section.
 301  */
 302 #ifndef CONFIG_LOCKDEP
 303 #  define disable_irq_nosync_lockdep(irq)       disable_irq_nosync(irq)
 304 #  define disable_irq_nosync_lockdep_irqsave(irq, flags) \
 305                                                 disable_irq_nosync(irq)
 306 #  define disable_irq_lockdep(irq)              disable_irq(irq)
 307 #  define enable_irq_lockdep(irq)               enable_irq(irq)
 308 #  define enable_irq_lockdep_irqrestore(irq, flags) \
 309                                                 enable_irq(irq)
 310 # endif
 311
 312 static inline int enable_irq_wake(unsigned int irq)
 313 {
 314         return 0;
 315 }
 316
 317 static inline int disable_irq_wake(unsigned int irq)
 318 {
 319         return 0;
 320 }
 321 #endif /* CONFIG_GENERIC_HARDIRQS */
 322
 323 #ifndef __ARCH_SET_SOFTIRQ_PENDING
 324 #define set_softirq_pending(x) (local_softirq_pending() = (x))
 325 #define or_softirq_pending(x)  (local_softirq_pending() |= (x))
 326 #endif
 327
 328 /* Some architectures might implement lazy enabling/disabling of
 329  * interrupts. In some cases, such as stop_machine, we might want
 330  * to ensure that after a local_irq_disable(), interrupts have
 331  * really been disabled in hardware. Such architectures need to
 332  * implement the following hook.
 333  */
 334 #ifndef hard_irq_disable
 335 #define hard_irq_disable()      do { } while(0)
 336 #endif
 337
 338 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
 339    frequency threaded job scheduling. For almost all the purposes
 340    tasklets are more than enough. F.e. all serial device BHs et
 341    al. should be converted to tasklets, not to softirqs.
 342  */
 343
 344 enum
 345 {
 346         HI_SOFTIRQ=0,
 347         TIMER_SOFTIRQ,
 348         NET_TX_SOFTIRQ,
 349         NET_RX_SOFTIRQ,
 350         BLOCK_SOFTIRQ,
 351         BLOCK_IOPOLL_SOFTIRQ,
 352         TASKLET_SOFTIRQ,
 353         SCHED_SOFTIRQ,
 354         HRTIMER_SOFTIRQ,
 355         RCU_SOFTIRQ,    /* Preferable RCU should always be the last softirq */
 356
 357         NR_SOFTIRQS
 358 };
 359
 360 /* map softirq index to softirq name. update 'softirq_to_name' in
 361  * kernel/softirq.c when adding a new softirq.
 362  */
 363 extern char *softirq_to_name[NR_SOFTIRQS];
 364
 365 /* softirq mask and active fields moved to irq_cpustat_t in
 366  * asm/hardirq.h to get better cache usage.  KAO
 367  */
 368
 369 struct softirq_action
 370 {
 371         void    (*action)(struct softirq_action *);
 372 };
 373
 374 asmlinkage void do_softirq(void);
 375 asmlinkage void __do_softirq(void);
 376 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
 377 extern void softirq_init(void);
 378 #define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)
 379 extern void raise_softirq_irqoff(unsigned int nr);
 380 extern void raise_softirq(unsigned int nr);
 381 extern void wakeup_softirqd(void);
 382
 383 /* This is the worklist that queues up per-cpu softirq work.
 384  *
 385  * send_remote_sendirq() adds work to these lists, and
 386  * the softirq handler itself dequeues from them.  The queues
 387  * are protected by disabling local cpu interrupts and they must
 388  * only be accessed by the local cpu that they are for.
 389  */
 390 DECLARE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list);
 391
 392 /* Try to send a softirq to a remote cpu.  If this cannot be done, the
 393  * work will be queued to the local cpu.
 394  */
 395 extern void send_remote_softirq(struct call_single_data *cp, int cpu, int softirq);
 396
 397 /* Like send_remote_softirq(), but the caller must disable local cpu interrupts
 398  * and compute the current cpu, passed in as 'this_cpu'.
 399  */
 400 extern void __send_remote_softirq(struct call_single_data *cp, int cpu,
 401                                   int this_cpu, int softirq);
 402
 403 /* Tasklets --- multithreaded analogue of BHs.
 404
 405    Main feature differing them of generic softirqs: tasklet
 406    is running only on one CPU simultaneously.
 407
 408    Main feature differing them of BHs: different tasklets
 409    may be run simultaneously on different CPUs.
 410
 411    Properties:
 412    * If tasklet_schedule() is called, then tasklet is guaranteed
 413      to be executed on some cpu at least once after this.
 414    * If the tasklet is already scheduled, but its excecution is still not
 415      started, it will be executed only once.
 416    * If this tasklet is already running on another CPU (or schedule is called
 417      from tasklet itself), it is rescheduled for later.
 418    * Tasklet is strictly serialized wrt itself, but not
 419      wrt another tasklets. If client needs some intertask synchronization,
 420      he makes it with spinlocks.
 421  */
 422
 423 struct tasklet_struct
 424 {
 425         struct tasklet_struct *next;
 426         unsigned long state;
 427         atomic_t count;
 428         void (*func)(unsigned long);
 429         unsigned long data;
 430 };
 431
 432 #define DECLARE_TASKLET(name, func, data) \
 433 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
 434
 435 #define DECLARE_TASKLET_DISABLED(name, func, data) \
 436 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
 437
 438
 439 enum
 440 {
 441         TASKLET_STATE_SCHED,    /* Tasklet is scheduled for execution */
 442         TASKLET_STATE_RUN       /* Tasklet is running (SMP only) */
 443 };
 444
 445 #ifdef CONFIG_SMP
 446 static inline int tasklet_trylock(struct tasklet_struct *t)
 447 {
 448         return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
 449 }
 450
 451 static inline void tasklet_unlock(struct tasklet_struct *t)
 452 {
 453         smp_mb__before_clear_bit();
 454         clear_bit(TASKLET_STATE_RUN, &(t)->state);
 455 }
 456
 457 static inline void tasklet_unlock_wait(struct tasklet_struct *t)
 458 {
 459         while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
 460 }
 461 #else
 462 #define tasklet_trylock(t) 1
 463 #define tasklet_unlock_wait(t) do { } while (0)
 464 #define tasklet_unlock(t) do { } while (0)
 465 #endif
 466
 467 extern void __tasklet_schedule(struct tasklet_struct *t);
 468
 469 static inline void tasklet_schedule(struct tasklet_struct *t)
 470 {
 471         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 472                 __tasklet_schedule(t);
 473 }
 474
 475 extern void __tasklet_hi_schedule(struct tasklet_struct *t);
 476
 477 static inline void tasklet_hi_schedule(struct tasklet_struct *t)
 478 {
 479         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 480                 __tasklet_hi_schedule(t);
 481 }
 482
 483 extern void __tasklet_hi_schedule_first(struct tasklet_struct *t);
 484
 485 /*
 486  * This version avoids touching any other tasklets. Needed for kmemcheck
 487  * in order not to take any page faults while enqueueing this tasklet;
 488  * consider VERY carefully whether you really need this or
 489  * tasklet_hi_schedule()...
 490  */
 491 static inline void tasklet_hi_schedule_first(struct tasklet_struct *t)
 492 {
 493         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
 494                 __tasklet_hi_schedule_first(t);
 495 }
 496
 497
 498 static inline void tasklet_disable_nosync(struct tasklet_struct *t)
 499 {
 500         atomic_inc(&t->count);
 501         smp_mb__after_atomic_inc();
 502 }
 503
 504 static inline void tasklet_disable(struct tasklet_struct *t)
 505 {
 506         tasklet_disable_nosync(t);
 507         tasklet_unlock_wait(t);
 508         smp_mb();
 509 }
 510
 511 static inline void tasklet_enable(struct tasklet_struct *t)
 512 {
 513         smp_mb__before_atomic_dec();
 514         atomic_dec(&t->count);
 515 }
 516
 517 static inline void tasklet_hi_enable(struct tasklet_struct *t)
 518 {
 519         smp_mb__before_atomic_dec();
 520         atomic_dec(&t->count);
 521 }
 522
 523 extern void tasklet_kill(struct tasklet_struct *t);
 524 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
 525 extern void tasklet_init(struct tasklet_struct *t,
 526                          void (*func)(unsigned long), unsigned long data);
 527
 528 struct tasklet_hrtimer {
 529         struct hrtimer          timer;
 530         struct tasklet_struct   tasklet;
 531         enum hrtimer_restart    (*function)(struct hrtimer *);
 532 };
 533
 534 extern void
 535 tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer,
 536                      enum hrtimer_restart (*function)(struct hrtimer *),
 537                      clockid_t which_clock, enum hrtimer_mode mode);
 538
 539 static inline
 540 int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time,
 541                           const enum hrtimer_mode mode)
 542 {
 543         return hrtimer_start(&ttimer->timer, time, mode);
 544 }
 545
 546 static inline
 547 void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
 548 {
 549         hrtimer_cancel(&ttimer->timer);
 550         tasklet_kill(&ttimer->tasklet);
 551 }
 552
 553 /*
 554  * Autoprobing for irqs:
 555  *
 556  * probe_irq_on() and probe_irq_off() provide robust primitives
 557  * for accurate IRQ probing during kernel initialization.  They are
 558  * reasonably simple to use, are not "fooled" by spurious interrupts,
 559  * and, unlike other attempts at IRQ probing, they do not get hung on
 560  * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
 561  *
 562  * For reasonably foolproof probing, use them as follows:
 563  *
 564  * 1. clear and/or mask the device's internal interrupt.
 565  * 2. sti();
 566  * 3. irqs = probe_irq_on();      // "take over" all unassigned idle IRQs
 567  * 4. enable the device and cause it to trigger an interrupt.
 568  * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
 569  * 6. irq = probe_irq_off(irqs);  // get IRQ number, 0=none, negative=multiple
 570  * 7. service the device to clear its pending interrupt.
 571  * 8. loop again if paranoia is required.
 572  *
 573  * probe_irq_on() returns a mask of allocated irq's.
 574  *
 575  * probe_irq_off() takes the mask as a parameter,
 576  * and returns the irq number which occurred,
 577  * or zero if none occurred, or a negative irq number
 578  * if more than one irq occurred.
 579  */
 580
 581 #if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
 582 static inline unsigned long probe_irq_on(void)
 583 {
 584         return 0;
 585 }
 586 static inline int probe_irq_off(unsigned long val)
 587 {
 588         return 0;
 589 }
 590 static inline unsigned int probe_irq_mask(unsigned long val)
 591 {
 592         return 0;
 593 }
 594 #else
 595 extern unsigned long probe_irq_on(void);        /* returns 0 on failure */
 596 extern int probe_irq_off(unsigned long);        /* returns 0 or negative on failure */
 597 extern unsigned int probe_irq_mask(unsigned long);      /* returns mask of ISA interrupts */
 598 #endif
 599
 600 #ifdef CONFIG_PROC_FS
 601 /* Initialize /proc/irq/ */
 602 extern void init_irq_proc(void);
 603 #else
 604 static inline void init_irq_proc(void)
 605 {
 606 }
 607 #endif
 608
 609 #if defined(CONFIG_GENERIC_HARDIRQS) && defined(CONFIG_DEBUG_SHIRQ)
 610 extern void debug_poll_all_shared_irqs(void);
 611 #else
 612 static inline void debug_poll_all_shared_irqs(void) { }
 613 #endif
 614
 615 int show_interrupts(struct seq_file *p, void *v);
 616
 617 struct irq_desc;
 618
 619 extern int early_irq_init(void);
 620 extern int arch_probe_nr_irqs(void);
 621 extern int arch_early_irq_init(void);
 622 extern int arch_init_chip_data(struct irq_desc *desc, int node);
 623
 624 #endif