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

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  1 /* SPDX-License-Identifier: GPL-2.0 */
  2 /* interrupt.h */
  3 #ifndef _LINUX_INTERRUPT_H
  4 #define _LINUX_INTERRUPT_H
  5 
  6 #include <linux/kernel.h>
  7 #include <linux/bitops.h>
  8 #include <linux/cpumask.h>
  9 #include <linux/irqreturn.h>
 10 #include <linux/irqnr.h>
 11 #include <linux/hardirq.h>
 12 #include <linux/irqflags.h>
 13 #include <linux/hrtimer.h>
 14 #include <linux/kref.h>
 15 #include <linux/workqueue.h>
 16 
 17 #include <linux/atomic.h>
 18 #include <asm/ptrace.h>
 19 #include <asm/irq.h>
 20 #include <asm/sections.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_SHARED - allow sharing the irq among several devices
 43  * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
 44  * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
 45  * IRQF_PERCPU - Interrupt is per cpu
 46  * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
 47  * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
 48  *                registered first in a shared interrupt is considered for
 49  *                performance reasons)
 50  * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
 51  *                Used by threaded interrupts which need to keep the
 52  *                irq line disabled until the threaded handler has been run.
 53  * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend.  Does not guarantee
 54  *                   that this interrupt will wake the system from a suspended
 55  *                   state.  See Documentation/power/suspend-and-interrupts.rst
 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  * IRQF_COND_SUSPEND - If the IRQ is shared with a NO_SUSPEND user, execute this
 61  *                interrupt handler after suspending interrupts. For system
 62  *                wakeup devices users need to implement wakeup detection in
 63  *                their interrupt handlers.
 64  */
 65 #define IRQF_SHARED             0x00000080
 66 #define IRQF_PROBE_SHARED       0x00000100
 67 #define __IRQF_TIMER            0x00000200
 68 #define IRQF_PERCPU             0x00000400
 69 #define IRQF_NOBALANCING        0x00000800
 70 #define IRQF_IRQPOLL            0x00001000
 71 #define IRQF_ONESHOT            0x00002000
 72 #define IRQF_NO_SUSPEND         0x00004000
 73 #define IRQF_FORCE_RESUME       0x00008000
 74 #define IRQF_NO_THREAD          0x00010000
 75 #define IRQF_EARLY_RESUME       0x00020000
 76 #define IRQF_COND_SUSPEND       0x00040000
 77 
 78 #define IRQF_TIMER              (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
 79 
 80 /*
 81  * These values can be returned by request_any_context_irq() and
 82  * describe the context the interrupt will be run in.
 83  *
 84  * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
 85  * IRQC_IS_NESTED - interrupt runs in a nested threaded context
 86  */
 87 enum {
 88         IRQC_IS_HARDIRQ = 0,
 89         IRQC_IS_NESTED,
 90 };
 91 
 92 typedef irqreturn_t (*irq_handler_t)(int, void *);
 93 
 94 /**
 95  * struct irqaction - per interrupt action descriptor
 96  * @handler:    interrupt handler function
 97  * @name:       name of the device
 98  * @dev_id:     cookie to identify the device
 99  * @percpu_dev_id:      cookie to identify the device
100  * @next:       pointer to the next irqaction for shared interrupts
101  * @irq:        interrupt number
102  * @flags:      flags (see IRQF_* above)
103  * @thread_fn:  interrupt handler function for threaded interrupts
104  * @thread:     thread pointer for threaded interrupts
105  * @secondary:  pointer to secondary irqaction (force threading)
106  * @thread_flags:       flags related to @thread
107  * @thread_mask:        bitmask for keeping track of @thread activity
108  * @dir:        pointer to the proc/irq/NN/name entry
109  */
110 struct irqaction {
111         irq_handler_t           handler;
112         void                    *dev_id;
113         void __percpu           *percpu_dev_id;
114         struct irqaction        *next;
115         irq_handler_t           thread_fn;
116         struct task_struct      *thread;
117         struct irqaction        *secondary;
118         unsigned int            irq;
119         unsigned int            flags;
120         unsigned long           thread_flags;
121         unsigned long           thread_mask;
122         const char              *name;
123         struct proc_dir_entry   *dir;
124 } ____cacheline_internodealigned_in_smp;
125 
126 extern irqreturn_t no_action(int cpl, void *dev_id);
127 
128 /*
129  * If a (PCI) device interrupt is not connected we set dev->irq to
130  * IRQ_NOTCONNECTED. This causes request_irq() to fail with -ENOTCONN, so we
131  * can distingiush that case from other error returns.
132  *
133  * 0x80000000 is guaranteed to be outside the available range of interrupts
134  * and easy to distinguish from other possible incorrect values.
135  */
136 #define IRQ_NOTCONNECTED        (1U << 31)
137 
138 extern int __must_check
139 request_threaded_irq(unsigned int irq, irq_handler_t handler,
140                      irq_handler_t thread_fn,
141                      unsigned long flags, const char *name, void *dev);
142 
143 /**
144  * request_irq - Add a handler for an interrupt line
145  * @irq:        The interrupt line to allocate
146  * @handler:    Function to be called when the IRQ occurs.
147  *              Primary handler for threaded interrupts
148  *              If NULL, the default primary handler is installed
149  * @flags:      Handling flags
150  * @name:       Name of the device generating this interrupt
151  * @dev:        A cookie passed to the handler function
152  *
153  * This call allocates an interrupt and establishes a handler; see
154  * the documentation for request_threaded_irq() for details.
155  */
156 static inline int __must_check
157 request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
158             const char *name, void *dev)
159 {
160         return request_threaded_irq(irq, handler, NULL, flags, name, dev);
161 }
162 
163 extern int __must_check
164 request_any_context_irq(unsigned int irq, irq_handler_t handler,
165                         unsigned long flags, const char *name, void *dev_id);
166 
167 extern int __must_check
168 __request_percpu_irq(unsigned int irq, irq_handler_t handler,
169                      unsigned long flags, const char *devname,
170                      void __percpu *percpu_dev_id);
171 
172 extern int __must_check
173 request_nmi(unsigned int irq, irq_handler_t handler, unsigned long flags,
174             const char *name, void *dev);
175 
176 static inline int __must_check
177 request_percpu_irq(unsigned int irq, irq_handler_t handler,
178                    const char *devname, void __percpu *percpu_dev_id)
179 {
180         return __request_percpu_irq(irq, handler, 0,
181                                     devname, percpu_dev_id);
182 }
183 
184 extern int __must_check
185 request_percpu_nmi(unsigned int irq, irq_handler_t handler,
186                    const char *devname, void __percpu *dev);
187 
188 extern const void *free_irq(unsigned int, void *);
189 extern void free_percpu_irq(unsigned int, void __percpu *);
190 
191 extern const void *free_nmi(unsigned int irq, void *dev_id);
192 extern void free_percpu_nmi(unsigned int irq, void __percpu *percpu_dev_id);
193 
194 struct device;
195 
196 extern int __must_check
197 devm_request_threaded_irq(struct device *dev, unsigned int irq,
198                           irq_handler_t handler, irq_handler_t thread_fn,
199                           unsigned long irqflags, const char *devname,
200                           void *dev_id);
201 
202 static inline int __must_check
203 devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
204                  unsigned long irqflags, const char *devname, void *dev_id)
205 {
206         return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
207                                          devname, dev_id);
208 }
209 
210 extern int __must_check
211 devm_request_any_context_irq(struct device *dev, unsigned int irq,
212                  irq_handler_t handler, unsigned long irqflags,
213                  const char *devname, void *dev_id);
214 
215 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
216 
217 /*
218  * On lockdep we dont want to enable hardirqs in hardirq
219  * context. Use local_irq_enable_in_hardirq() to annotate
220  * kernel code that has to do this nevertheless (pretty much
221  * the only valid case is for old/broken hardware that is
222  * insanely slow).
223  *
224  * NOTE: in theory this might break fragile code that relies
225  * on hardirq delivery - in practice we dont seem to have such
226  * places left. So the only effect should be slightly increased
227  * irqs-off latencies.
228  */
229 #ifdef CONFIG_LOCKDEP
230 # define local_irq_enable_in_hardirq()  do { } while (0)
231 #else
232 # define local_irq_enable_in_hardirq()  local_irq_enable()
233 #endif
234 
235 bool irq_has_action(unsigned int irq);
236 extern void disable_irq_nosync(unsigned int irq);
237 extern bool disable_hardirq(unsigned int irq);
238 extern void disable_irq(unsigned int irq);
239 extern void disable_percpu_irq(unsigned int irq);
240 extern void enable_irq(unsigned int irq);
241 extern void enable_percpu_irq(unsigned int irq, unsigned int type);
242 extern bool irq_percpu_is_enabled(unsigned int irq);
243 extern void irq_wake_thread(unsigned int irq, void *dev_id);
244 
245 extern void disable_nmi_nosync(unsigned int irq);
246 extern void disable_percpu_nmi(unsigned int irq);
247 extern void enable_nmi(unsigned int irq);
248 extern void enable_percpu_nmi(unsigned int irq, unsigned int type);
249 extern int prepare_percpu_nmi(unsigned int irq);
250 extern void teardown_percpu_nmi(unsigned int irq);
251 
252 extern int irq_inject_interrupt(unsigned int irq);
253 
254 /* The following three functions are for the core kernel use only. */
255 extern void suspend_device_irqs(void);
256 extern void resume_device_irqs(void);
257 extern void rearm_wake_irq(unsigned int irq);
258 
259 /**
260  * struct irq_affinity_notify - context for notification of IRQ affinity changes
261  * @irq:                Interrupt to which notification applies
262  * @kref:               Reference count, for internal use
263  * @work:               Work item, for internal use
264  * @notify:             Function to be called on change.  This will be
265  *                      called in process context.
266  * @release:            Function to be called on release.  This will be
267  *                      called in process context.  Once registered, the
268  *                      structure must only be freed when this function is
269  *                      called or later.
270  */
271 struct irq_affinity_notify {
272         unsigned int irq;
273         struct kref kref;
274         struct work_struct work;
275         void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
276         void (*release)(struct kref *ref);
277 };
278 
279 #define IRQ_AFFINITY_MAX_SETS  4
280 
281 /**
282  * struct irq_affinity - Description for automatic irq affinity assignements
283  * @pre_vectors:        Don't apply affinity to @pre_vectors at beginning of
284  *                      the MSI(-X) vector space
285  * @post_vectors:       Don't apply affinity to @post_vectors at end of
286  *                      the MSI(-X) vector space
287  * @nr_sets:            The number of interrupt sets for which affinity
288  *                      spreading is required
289  * @set_size:           Array holding the size of each interrupt set
290  * @calc_sets:          Callback for calculating the number and size
291  *                      of interrupt sets
292  * @priv:               Private data for usage by @calc_sets, usually a
293  *                      pointer to driver/device specific data.
294  */
295 struct irq_affinity {
296         unsigned int    pre_vectors;
297         unsigned int    post_vectors;
298         unsigned int    nr_sets;
299         unsigned int    set_size[IRQ_AFFINITY_MAX_SETS];
300         void            (*calc_sets)(struct irq_affinity *, unsigned int nvecs);
301         void            *priv;
302 };
303 
304 /**
305  * struct irq_affinity_desc - Interrupt affinity descriptor
306  * @mask:       cpumask to hold the affinity assignment
307  * @is_managed: 1 if the interrupt is managed internally
308  */
309 struct irq_affinity_desc {
310         struct cpumask  mask;
311         unsigned int    is_managed : 1;
312 };
313 
314 #if defined(CONFIG_SMP)
315 
316 extern cpumask_var_t irq_default_affinity;
317 
318 /* Internal implementation. Use the helpers below */
319 extern int __irq_set_affinity(unsigned int irq, const struct cpumask *cpumask,
320                               bool force);
321 
322 /**
323  * irq_set_affinity - Set the irq affinity of a given irq
324  * @irq:        Interrupt to set affinity
325  * @cpumask:    cpumask
326  *
327  * Fails if cpumask does not contain an online CPU
328  */
329 static inline int
330 irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
331 {
332         return __irq_set_affinity(irq, cpumask, false);
333 }
334 
335 /**
336  * irq_force_affinity - Force the irq affinity of a given irq
337  * @irq:        Interrupt to set affinity
338  * @cpumask:    cpumask
339  *
340  * Same as irq_set_affinity, but without checking the mask against
341  * online cpus.
342  *
343  * Solely for low level cpu hotplug code, where we need to make per
344  * cpu interrupts affine before the cpu becomes online.
345  */
346 static inline int
347 irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
348 {
349         return __irq_set_affinity(irq, cpumask, true);
350 }
351 
352 extern int irq_can_set_affinity(unsigned int irq);
353 extern int irq_select_affinity(unsigned int irq);
354 
355 extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
356 extern int irq_update_affinity_desc(unsigned int irq,
357                                     struct irq_affinity_desc *affinity);
358 
359 extern int
360 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
361 
362 struct irq_affinity_desc *
363 irq_create_affinity_masks(unsigned int nvec, struct irq_affinity *affd);
364 
365 unsigned int irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
366                                        const struct irq_affinity *affd);
367 
368 #else /* CONFIG_SMP */
369 
370 static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
371 {
372         return -EINVAL;
373 }
374 
375 static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
376 {
377         return 0;
378 }
379 
380 static inline int irq_can_set_affinity(unsigned int irq)
381 {
382         return 0;
383 }
384 
385 static inline int irq_select_affinity(unsigned int irq)  { return 0; }
386 
387 static inline int irq_set_affinity_hint(unsigned int irq,
388                                         const struct cpumask *m)
389 {
390         return -EINVAL;
391 }
392 
393 static inline int irq_update_affinity_desc(unsigned int irq,
394                                            struct irq_affinity_desc *affinity)
395 {
396         return -EINVAL;
397 }
398 
399 static inline int
400 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
401 {
402         return 0;
403 }
404 
405 static inline struct irq_affinity_desc *
406 irq_create_affinity_masks(unsigned int nvec, struct irq_affinity *affd)
407 {
408         return NULL;
409 }
410 
411 static inline unsigned int
412 irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
413                           const struct irq_affinity *affd)
414 {
415         return maxvec;
416 }
417 
418 #endif /* CONFIG_SMP */
419 
420 /*
421  * Special lockdep variants of irq disabling/enabling.
422  * These should be used for locking constructs that
423  * know that a particular irq context which is disabled,
424  * and which is the only irq-context user of a lock,
425  * that it's safe to take the lock in the irq-disabled
426  * section without disabling hardirqs.
427  *
428  * On !CONFIG_LOCKDEP they are equivalent to the normal
429  * irq disable/enable methods.
430  */
431 static inline void disable_irq_nosync_lockdep(unsigned int irq)
432 {
433         disable_irq_nosync(irq);
434 #ifdef CONFIG_LOCKDEP
435         local_irq_disable();
436 #endif
437 }
438 
439 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
440 {
441         disable_irq_nosync(irq);
442 #ifdef CONFIG_LOCKDEP
443         local_irq_save(*flags);
444 #endif
445 }
446 
447 static inline void disable_irq_lockdep(unsigned int irq)
448 {
449         disable_irq(irq);
450 #ifdef CONFIG_LOCKDEP
451         local_irq_disable();
452 #endif
453 }
454 
455 static inline void enable_irq_lockdep(unsigned int irq)
456 {
457 #ifdef CONFIG_LOCKDEP
458         local_irq_enable();
459 #endif
460         enable_irq(irq);
461 }
462 
463 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
464 {
465 #ifdef CONFIG_LOCKDEP
466         local_irq_restore(*flags);
467 #endif
468         enable_irq(irq);
469 }
470 
471 /* IRQ wakeup (PM) control: */
472 extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
473 
474 static inline int enable_irq_wake(unsigned int irq)
475 {
476         return irq_set_irq_wake(irq, 1);
477 }
478 
479 static inline int disable_irq_wake(unsigned int irq)
480 {
481         return irq_set_irq_wake(irq, 0);
482 }
483 
484 /*
485  * irq_get_irqchip_state/irq_set_irqchip_state specific flags
486  */
487 enum irqchip_irq_state {
488         IRQCHIP_STATE_PENDING,          /* Is interrupt pending? */
489         IRQCHIP_STATE_ACTIVE,           /* Is interrupt in progress? */
490         IRQCHIP_STATE_MASKED,           /* Is interrupt masked? */
491         IRQCHIP_STATE_LINE_LEVEL,       /* Is IRQ line high? */
492 };
493 
494 extern int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
495                                  bool *state);
496 extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
497                                  bool state);
498 
499 #ifdef CONFIG_IRQ_FORCED_THREADING
500 # ifdef CONFIG_PREEMPT_RT
501 #  define force_irqthreads      (true)
502 # else
503 extern bool force_irqthreads;
504 # endif
505 #else
506 #define force_irqthreads        (0)
507 #endif
508 
509 #ifndef local_softirq_pending
510 
511 #ifndef local_softirq_pending_ref
512 #define local_softirq_pending_ref irq_stat.__softirq_pending
513 #endif
514 
515 #define local_softirq_pending() (__this_cpu_read(local_softirq_pending_ref))
516 #define set_softirq_pending(x)  (__this_cpu_write(local_softirq_pending_ref, (x)))
517 #define or_softirq_pending(x)   (__this_cpu_or(local_softirq_pending_ref, (x)))
518 
519 #endif /* local_softirq_pending */
520 
521 /* Some architectures might implement lazy enabling/disabling of
522  * interrupts. In some cases, such as stop_machine, we might want
523  * to ensure that after a local_irq_disable(), interrupts have
524  * really been disabled in hardware. Such architectures need to
525  * implement the following hook.
526  */
527 #ifndef hard_irq_disable
528 #define hard_irq_disable()      do { } while(0)
529 #endif
530 
531 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
532    frequency threaded job scheduling. For almost all the purposes
533    tasklets are more than enough. F.e. all serial device BHs et
534    al. should be converted to tasklets, not to softirqs.
535  */
536 
537 enum
538 {
539         HI_SOFTIRQ=0,
540         TIMER_SOFTIRQ,
541         NET_TX_SOFTIRQ,
542         NET_RX_SOFTIRQ,
543         BLOCK_SOFTIRQ,
544         IRQ_POLL_SOFTIRQ,
545         TASKLET_SOFTIRQ,
546         SCHED_SOFTIRQ,
547         HRTIMER_SOFTIRQ,
548         RCU_SOFTIRQ,    /* Preferable RCU should always be the last softirq */
549 
550         NR_SOFTIRQS
551 };
552 
553 #define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ))
554 
555 /* map softirq index to softirq name. update 'softirq_to_name' in
556  * kernel/softirq.c when adding a new softirq.
557  */
558 extern const char * const softirq_to_name[NR_SOFTIRQS];
559 
560 /* softirq mask and active fields moved to irq_cpustat_t in
561  * asm/hardirq.h to get better cache usage.  KAO
562  */
563 
564 struct softirq_action
565 {
566         void    (*action)(struct softirq_action *);
567 };
568 
569 asmlinkage void do_softirq(void);
570 asmlinkage void __do_softirq(void);
571 
572 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
573 extern void softirq_init(void);
574 extern void __raise_softirq_irqoff(unsigned int nr);
575 
576 extern void raise_softirq_irqoff(unsigned int nr);
577 extern void raise_softirq(unsigned int nr);
578 
579 DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
580 
581 static inline struct task_struct *this_cpu_ksoftirqd(void)
582 {
583         return this_cpu_read(ksoftirqd);
584 }
585 
586 /* Tasklets --- multithreaded analogue of BHs.
587 
588    This API is deprecated. Please consider using threaded IRQs instead:
589    https://lore.kernel.org/lkml/20200716081538.2sivhkj4hcyrusem@linutronix.de
590 
591    Main feature differing them of generic softirqs: tasklet
592    is running only on one CPU simultaneously.
593 
594    Main feature differing them of BHs: different tasklets
595    may be run simultaneously on different CPUs.
596 
597    Properties:
598    * If tasklet_schedule() is called, then tasklet is guaranteed
599      to be executed on some cpu at least once after this.
600    * If the tasklet is already scheduled, but its execution is still not
601      started, it will be executed only once.
602    * If this tasklet is already running on another CPU (or schedule is called
603      from tasklet itself), it is rescheduled for later.
604    * Tasklet is strictly serialized wrt itself, but not
605      wrt another tasklets. If client needs some intertask synchronization,
606      he makes it with spinlocks.
607  */
608 
609 struct tasklet_struct
610 {
611         struct tasklet_struct *next;
612         unsigned long state;
613         atomic_t count;
614         bool use_callback;
615         union {
616                 void (*func)(unsigned long data);
617                 void (*callback)(struct tasklet_struct *t);
618         };
619         unsigned long data;
620 };
621 
622 #define DECLARE_TASKLET(name, _callback)                \
623 struct tasklet_struct name = {                          \
624         .count = ATOMIC_INIT(0),                        \
625         .callback = _callback,                          \
626         .use_callback = true,                           \
627 }
628 
629 #define DECLARE_TASKLET_DISABLED(name, _callback)       \
630 struct tasklet_struct name = {                          \
631         .count = ATOMIC_INIT(1),                        \
632         .callback = _callback,                          \
633         .use_callback = true,                           \
634 }
635 
636 #define from_tasklet(var, callback_tasklet, tasklet_fieldname)  \
637         container_of(callback_tasklet, typeof(*var), tasklet_fieldname)
638 
639 #define DECLARE_TASKLET_OLD(name, _func)                \
640 struct tasklet_struct name = {                          \
641         .count = ATOMIC_INIT(0),                        \
642         .func = _func,                                  \
643 }
644 
645 #define DECLARE_TASKLET_DISABLED_OLD(name, _func)       \
646 struct tasklet_struct name = {                          \
647         .count = ATOMIC_INIT(1),                        \
648         .func = _func,                                  \
649 }
650 
651 enum
652 {
653         TASKLET_STATE_SCHED,    /* Tasklet is scheduled for execution */
654         TASKLET_STATE_RUN       /* Tasklet is running (SMP only) */
655 };
656 
657 #ifdef CONFIG_SMP
658 static inline int tasklet_trylock(struct tasklet_struct *t)
659 {
660         return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
661 }
662 
663 static inline void tasklet_unlock(struct tasklet_struct *t)
664 {
665         smp_mb__before_atomic();
666         clear_bit(TASKLET_STATE_RUN, &(t)->state);
667 }
668 
669 static inline void tasklet_unlock_wait(struct tasklet_struct *t)
670 {
671         while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
672 }
673 #else
674 #define tasklet_trylock(t) 1
675 #define tasklet_unlock_wait(t) do { } while (0)
676 #define tasklet_unlock(t) do { } while (0)
677 #endif
678 
679 extern void __tasklet_schedule(struct tasklet_struct *t);
680 
681 static inline void tasklet_schedule(struct tasklet_struct *t)
682 {
683         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
684                 __tasklet_schedule(t);
685 }
686 
687 extern void __tasklet_hi_schedule(struct tasklet_struct *t);
688 
689 static inline void tasklet_hi_schedule(struct tasklet_struct *t)
690 {
691         if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
692                 __tasklet_hi_schedule(t);
693 }
694 
695 static inline void tasklet_disable_nosync(struct tasklet_struct *t)
696 {
697         atomic_inc(&t->count);
698         smp_mb__after_atomic();
699 }
700 
701 static inline void tasklet_disable(struct tasklet_struct *t)
702 {
703         tasklet_disable_nosync(t);
704         tasklet_unlock_wait(t);
705         smp_mb();
706 }
707 
708 static inline void tasklet_enable(struct tasklet_struct *t)
709 {
710         smp_mb__before_atomic();
711         atomic_dec(&t->count);
712 }
713 
714 extern void tasklet_kill(struct tasklet_struct *t);
715 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
716 extern void tasklet_init(struct tasklet_struct *t,
717                          void (*func)(unsigned long), unsigned long data);
718 extern void tasklet_setup(struct tasklet_struct *t,
719                           void (*callback)(struct tasklet_struct *));
720 
721 /*
722  * Autoprobing for irqs:
723  *
724  * probe_irq_on() and probe_irq_off() provide robust primitives
725  * for accurate IRQ probing during kernel initialization.  They are
726  * reasonably simple to use, are not "fooled" by spurious interrupts,
727  * and, unlike other attempts at IRQ probing, they do not get hung on
728  * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
729  *
730  * For reasonably foolproof probing, use them as follows:
731  *
732  * 1. clear and/or mask the device's internal interrupt.
733  * 2. sti();
734  * 3. irqs = probe_irq_on();      // "take over" all unassigned idle IRQs
735  * 4. enable the device and cause it to trigger an interrupt.
736  * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
737  * 6. irq = probe_irq_off(irqs);  // get IRQ number, 0=none, negative=multiple
738  * 7. service the device to clear its pending interrupt.
739  * 8. loop again if paranoia is required.
740  *
741  * probe_irq_on() returns a mask of allocated irq's.
742  *
743  * probe_irq_off() takes the mask as a parameter,
744  * and returns the irq number which occurred,
745  * or zero if none occurred, or a negative irq number
746  * if more than one irq occurred.
747  */
748 
749 #if !defined(CONFIG_GENERIC_IRQ_PROBE) 
750 static inline unsigned long probe_irq_on(void)
751 {
752         return 0;
753 }
754 static inline int probe_irq_off(unsigned long val)
755 {
756         return 0;
757 }
758 static inline unsigned int probe_irq_mask(unsigned long val)
759 {
760         return 0;
761 }
762 #else
763 extern unsigned long probe_irq_on(void);        /* returns 0 on failure */
764 extern int probe_irq_off(unsigned long);        /* returns 0 or negative on failure */
765 extern unsigned int probe_irq_mask(unsigned long);      /* returns mask of ISA interrupts */
766 #endif
767 
768 #ifdef CONFIG_PROC_FS
769 /* Initialize /proc/irq/ */
770 extern void init_irq_proc(void);
771 #else
772 static inline void init_irq_proc(void)
773 {
774 }
775 #endif
776 
777 #ifdef CONFIG_IRQ_TIMINGS
778 void irq_timings_enable(void);
779 void irq_timings_disable(void);
780 u64 irq_timings_next_event(u64 now);
781 #endif
782 
783 struct seq_file;
784 int show_interrupts(struct seq_file *p, void *v);
785 int arch_show_interrupts(struct seq_file *p, int prec);
786 
787 extern int early_irq_init(void);
788 extern int arch_probe_nr_irqs(void);
789 extern int arch_early_irq_init(void);
790 
791 /*
792  * We want to know which function is an entrypoint of a hardirq or a softirq.
793  */
794 #ifndef __irq_entry
795 # define __irq_entry     __section(".irqentry.text")
796 #endif
797 
798 #define __softirq_entry  __section(".softirqentry.text")
799 
800 #endif
801 

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