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 * IRQF_NO_AUTOEN - Don't enable IRQ or NMI automatically when users request it.
65 * Users will enable it explicitly by enable_irq() or enable_nmi()
66 * later.
67 */
68 #define IRQF_SHARED 0x00000080
69 #define IRQF_PROBE_SHARED 0x00000100
70 #define __IRQF_TIMER 0x00000200
71 #define IRQF_PERCPU 0x00000400
72 #define IRQF_NOBALANCING 0x00000800
73 #define IRQF_IRQPOLL 0x00001000
74 #define IRQF_ONESHOT 0x00002000
75 #define IRQF_NO_SUSPEND 0x00004000
76 #define IRQF_FORCE_RESUME 0x00008000
77 #define IRQF_NO_THREAD 0x00010000
78 #define IRQF_EARLY_RESUME 0x00020000
79 #define IRQF_COND_SUSPEND 0x00040000
80 #define IRQF_NO_AUTOEN 0x00080000
81
82 #define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
83
84 /*
85 * These values can be returned by request_any_context_irq() and
86 * describe the context the interrupt will be run in.
87 *
88 * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
89 * IRQC_IS_NESTED - interrupt runs in a nested threaded context
90 */
91 enum {
92 IRQC_IS_HARDIRQ = 0,
93 IRQC_IS_NESTED,
94 };
95
96 typedef irqreturn_t (*irq_handler_t)(int, void *);
97
98 /**
99 * struct irqaction - per interrupt action descriptor
100 * @handler: interrupt handler function
101 * @name: name of the device
102 * @dev_id: cookie to identify the device
103 * @percpu_dev_id: cookie to identify the device
104 * @next: pointer to the next irqaction for shared interrupts
105 * @irq: interrupt number
106 * @flags: flags (see IRQF_* above)
107 * @thread_fn: interrupt handler function for threaded interrupts
108 * @thread: thread pointer for threaded interrupts
109 * @secondary: pointer to secondary irqaction (force threading)
110 * @thread_flags: flags related to @thread
111 * @thread_mask: bitmask for keeping track of @thread activity
112 * @dir: pointer to the proc/irq/NN/name entry
113 */
114 struct irqaction {
115 irq_handler_t handler;
116 void *dev_id;
117 void __percpu *percpu_dev_id;
118 struct irqaction *next;
119 irq_handler_t thread_fn;
120 struct task_struct *thread;
121 struct irqaction *secondary;
122 unsigned int irq;
123 unsigned int flags;
124 unsigned long thread_flags;
125 unsigned long thread_mask;
126 const char *name;
127 struct proc_dir_entry *dir;
128 } ____cacheline_internodealigned_in_smp;
129
130 extern irqreturn_t no_action(int cpl, void *dev_id);
131
132 /*
133 * If a (PCI) device interrupt is not connected we set dev->irq to
134 * IRQ_NOTCONNECTED. This causes request_irq() to fail with -ENOTCONN, so we
135 * can distingiush that case from other error returns.
136 *
137 * 0x80000000 is guaranteed to be outside the available range of interrupts
138 * and easy to distinguish from other possible incorrect values.
139 */
140 #define IRQ_NOTCONNECTED (1U << 31)
141
142 extern int __must_check
143 request_threaded_irq(unsigned int irq, irq_handler_t handler,
144 irq_handler_t thread_fn,
145 unsigned long flags, const char *name, void *dev);
146
147 static inline int __must_check
request_irq(unsigned int irq,irq_handler_t handler,unsigned long flags,const char * name,void * dev)148 request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
149 const char *name, void *dev)
150 {
151 return request_threaded_irq(irq, handler, NULL, flags, name, dev);
152 }
153
154 extern int __must_check
155 request_any_context_irq(unsigned int irq, irq_handler_t handler,
156 unsigned long flags, const char *name, void *dev_id);
157
158 extern int __must_check
159 __request_percpu_irq(unsigned int irq, irq_handler_t handler,
160 unsigned long flags, const char *devname,
161 void __percpu *percpu_dev_id);
162
163 extern int __must_check
164 request_nmi(unsigned int irq, irq_handler_t handler, unsigned long flags,
165 const char *name, void *dev);
166
167 static inline int __must_check
request_percpu_irq(unsigned int irq,irq_handler_t handler,const char * devname,void __percpu * percpu_dev_id)168 request_percpu_irq(unsigned int irq, irq_handler_t handler,
169 const char *devname, void __percpu *percpu_dev_id)
170 {
171 return __request_percpu_irq(irq, handler, 0,
172 devname, percpu_dev_id);
173 }
174
175 extern int __must_check
176 request_percpu_nmi(unsigned int irq, irq_handler_t handler,
177 const char *devname, void __percpu *dev);
178
179 extern const void *free_irq(unsigned int, void *);
180 extern void free_percpu_irq(unsigned int, void __percpu *);
181
182 extern const void *free_nmi(unsigned int irq, void *dev_id);
183 extern void free_percpu_nmi(unsigned int irq, void __percpu *percpu_dev_id);
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
devm_request_irq(struct device * dev,unsigned int irq,irq_handler_t handler,unsigned long irqflags,const char * devname,void * dev_id)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 int __must_check
202 devm_request_any_context_irq(struct device *dev, unsigned int irq,
203 irq_handler_t handler, unsigned long irqflags,
204 const char *devname, void *dev_id);
205
206 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
207
208 /*
209 * On lockdep we dont want to enable hardirqs in hardirq
210 * context. Use local_irq_enable_in_hardirq() to annotate
211 * kernel code that has to do this nevertheless (pretty much
212 * the only valid case is for old/broken hardware that is
213 * insanely slow).
214 *
215 * NOTE: in theory this might break fragile code that relies
216 * on hardirq delivery - in practice we dont seem to have such
217 * places left. So the only effect should be slightly increased
218 * irqs-off latencies.
219 */
220 #ifdef CONFIG_LOCKDEP
221 # define local_irq_enable_in_hardirq() do { } while (0)
222 #else
223 # define local_irq_enable_in_hardirq() local_irq_enable()
224 #endif
225
226 extern void disable_irq_nosync(unsigned int irq);
227 extern bool disable_hardirq(unsigned int irq);
228 extern void disable_irq(unsigned int irq);
229 extern void disable_percpu_irq(unsigned int irq);
230 extern void enable_irq(unsigned int irq);
231 extern void enable_percpu_irq(unsigned int irq, unsigned int type);
232 extern bool irq_percpu_is_enabled(unsigned int irq);
233 extern void irq_wake_thread(unsigned int irq, void *dev_id);
234
235 extern void disable_nmi_nosync(unsigned int irq);
236 extern void disable_percpu_nmi(unsigned int irq);
237 extern void enable_nmi(unsigned int irq);
238 extern void enable_percpu_nmi(unsigned int irq, unsigned int type);
239 extern int prepare_percpu_nmi(unsigned int irq);
240 extern void teardown_percpu_nmi(unsigned int irq);
241
242 /* The following three functions are for the core kernel use only. */
243 extern void suspend_device_irqs(void);
244 extern void resume_device_irqs(void);
245 extern void rearm_wake_irq(unsigned int irq);
246
247 /**
248 * struct irq_affinity_notify - context for notification of IRQ affinity changes
249 * @irq: Interrupt to which notification applies
250 * @kref: Reference count, for internal use
251 * @work: Work item, for internal use
252 * @notify: Function to be called on change. This will be
253 * called in process context.
254 * @release: Function to be called on release. This will be
255 * called in process context. Once registered, the
256 * structure must only be freed when this function is
257 * called or later.
258 */
259 struct irq_affinity_notify {
260 unsigned int irq;
261 struct kref kref;
262 struct work_struct work;
263 void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
264 void (*release)(struct kref *ref);
265 };
266
267 #define IRQ_AFFINITY_MAX_SETS 4
268
269 /**
270 * struct irq_affinity - Description for automatic irq affinity assignements
271 * @pre_vectors: Don't apply affinity to @pre_vectors at beginning of
272 * the MSI(-X) vector space
273 * @post_vectors: Don't apply affinity to @post_vectors at end of
274 * the MSI(-X) vector space
275 * @nr_sets: The number of interrupt sets for which affinity
276 * spreading is required
277 * @set_size: Array holding the size of each interrupt set
278 * @calc_sets: Callback for calculating the number and size
279 * of interrupt sets
280 * @priv: Private data for usage by @calc_sets, usually a
281 * pointer to driver/device specific data.
282 */
283 struct irq_affinity {
284 unsigned int pre_vectors;
285 unsigned int post_vectors;
286 unsigned int nr_sets;
287 unsigned int set_size[IRQ_AFFINITY_MAX_SETS];
288 void (*calc_sets)(struct irq_affinity *, unsigned int nvecs);
289 void *priv;
290 };
291
292 /**
293 * struct irq_affinity_desc - Interrupt affinity descriptor
294 * @mask: cpumask to hold the affinity assignment
295 * @is_managed: 1 if the interrupt is managed internally
296 */
297 struct irq_affinity_desc {
298 struct cpumask mask;
299 unsigned int is_managed : 1;
300 };
301
302 #if defined(CONFIG_SMP)
303
304 extern cpumask_var_t irq_default_affinity;
305
306 /* Internal implementation. Use the helpers below */
307 extern int __irq_set_affinity(unsigned int irq, const struct cpumask *cpumask,
308 bool force);
309
310 /**
311 * irq_set_affinity - Set the irq affinity of a given irq
312 * @irq: Interrupt to set affinity
313 * @cpumask: cpumask
314 *
315 * Fails if cpumask does not contain an online CPU
316 */
317 static inline int
irq_set_affinity(unsigned int irq,const struct cpumask * cpumask)318 irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
319 {
320 return __irq_set_affinity(irq, cpumask, false);
321 }
322
323 /**
324 * irq_force_affinity - Force the irq affinity of a given irq
325 * @irq: Interrupt to set affinity
326 * @cpumask: cpumask
327 *
328 * Same as irq_set_affinity, but without checking the mask against
329 * online cpus.
330 *
331 * Solely for low level cpu hotplug code, where we need to make per
332 * cpu interrupts affine before the cpu becomes online.
333 */
334 static inline int
irq_force_affinity(unsigned int irq,const struct cpumask * cpumask)335 irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
336 {
337 return __irq_set_affinity(irq, cpumask, true);
338 }
339
340 extern int irq_can_set_affinity(unsigned int irq);
341 extern int irq_select_affinity(unsigned int irq);
342
343 extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
344
345 extern int
346 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
347
348 struct irq_affinity_desc *
349 irq_create_affinity_masks(unsigned int nvec, struct irq_affinity *affd);
350
351 unsigned int irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
352 const struct irq_affinity *affd);
353
354 #else /* CONFIG_SMP */
355
irq_set_affinity(unsigned int irq,const struct cpumask * m)356 static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
357 {
358 return -EINVAL;
359 }
360
irq_force_affinity(unsigned int irq,const struct cpumask * cpumask)361 static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
362 {
363 return 0;
364 }
365
irq_can_set_affinity(unsigned int irq)366 static inline int irq_can_set_affinity(unsigned int irq)
367 {
368 return 0;
369 }
370
irq_select_affinity(unsigned int irq)371 static inline int irq_select_affinity(unsigned int irq) { return 0; }
372
irq_set_affinity_hint(unsigned int irq,const struct cpumask * m)373 static inline int irq_set_affinity_hint(unsigned int irq,
374 const struct cpumask *m)
375 {
376 return -EINVAL;
377 }
378
379 static inline int
irq_set_affinity_notifier(unsigned int irq,struct irq_affinity_notify * notify)380 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
381 {
382 return 0;
383 }
384
385 static inline struct irq_affinity_desc *
irq_create_affinity_masks(unsigned int nvec,struct irq_affinity * affd)386 irq_create_affinity_masks(unsigned int nvec, struct irq_affinity *affd)
387 {
388 return NULL;
389 }
390
391 static inline unsigned int
irq_calc_affinity_vectors(unsigned int minvec,unsigned int maxvec,const struct irq_affinity * affd)392 irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
393 const struct irq_affinity *affd)
394 {
395 return maxvec;
396 }
397
398 #endif /* CONFIG_SMP */
399
400 /*
401 * Special lockdep variants of irq disabling/enabling.
402 * These should be used for locking constructs that
403 * know that a particular irq context which is disabled,
404 * and which is the only irq-context user of a lock,
405 * that it's safe to take the lock in the irq-disabled
406 * section without disabling hardirqs.
407 *
408 * On !CONFIG_LOCKDEP they are equivalent to the normal
409 * irq disable/enable methods.
410 */
disable_irq_nosync_lockdep(unsigned int irq)411 static inline void disable_irq_nosync_lockdep(unsigned int irq)
412 {
413 disable_irq_nosync(irq);
414 #ifdef CONFIG_LOCKDEP
415 local_irq_disable();
416 #endif
417 }
418
disable_irq_nosync_lockdep_irqsave(unsigned int irq,unsigned long * flags)419 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
420 {
421 disable_irq_nosync(irq);
422 #ifdef CONFIG_LOCKDEP
423 local_irq_save(*flags);
424 #endif
425 }
426
disable_irq_lockdep(unsigned int irq)427 static inline void disable_irq_lockdep(unsigned int irq)
428 {
429 disable_irq(irq);
430 #ifdef CONFIG_LOCKDEP
431 local_irq_disable();
432 #endif
433 }
434
enable_irq_lockdep(unsigned int irq)435 static inline void enable_irq_lockdep(unsigned int irq)
436 {
437 #ifdef CONFIG_LOCKDEP
438 local_irq_enable();
439 #endif
440 enable_irq(irq);
441 }
442
enable_irq_lockdep_irqrestore(unsigned int irq,unsigned long * flags)443 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
444 {
445 #ifdef CONFIG_LOCKDEP
446 local_irq_restore(*flags);
447 #endif
448 enable_irq(irq);
449 }
450
451 /* IRQ wakeup (PM) control: */
452 extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
453
enable_irq_wake(unsigned int irq)454 static inline int enable_irq_wake(unsigned int irq)
455 {
456 return irq_set_irq_wake(irq, 1);
457 }
458
disable_irq_wake(unsigned int irq)459 static inline int disable_irq_wake(unsigned int irq)
460 {
461 return irq_set_irq_wake(irq, 0);
462 }
463
464 /*
465 * irq_get_irqchip_state/irq_set_irqchip_state specific flags
466 */
467 enum irqchip_irq_state {
468 IRQCHIP_STATE_PENDING, /* Is interrupt pending? */
469 IRQCHIP_STATE_ACTIVE, /* Is interrupt in progress? */
470 IRQCHIP_STATE_MASKED, /* Is interrupt masked? */
471 IRQCHIP_STATE_LINE_LEVEL, /* Is IRQ line high? */
472 };
473
474 extern int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
475 bool *state);
476 extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
477 bool state);
478
479 #ifdef CONFIG_IRQ_FORCED_THREADING
480 # ifdef CONFIG_PREEMPT_RT
481 # define force_irqthreads (true)
482 # else
483 extern bool force_irqthreads;
484 # endif
485 #else
486 #define force_irqthreads (0)
487 #endif
488
489 #ifndef local_softirq_pending
490
491 #ifndef local_softirq_pending_ref
492 #define local_softirq_pending_ref irq_stat.__softirq_pending
493 #endif
494
495 #define local_softirq_pending() (__this_cpu_read(local_softirq_pending_ref))
496 #define set_softirq_pending(x) (__this_cpu_write(local_softirq_pending_ref, (x)))
497 #define or_softirq_pending(x) (__this_cpu_or(local_softirq_pending_ref, (x)))
498
499 #endif /* local_softirq_pending */
500
501 /* Some architectures might implement lazy enabling/disabling of
502 * interrupts. In some cases, such as stop_machine, we might want
503 * to ensure that after a local_irq_disable(), interrupts have
504 * really been disabled in hardware. Such architectures need to
505 * implement the following hook.
506 */
507 #ifndef hard_irq_disable
508 #define hard_irq_disable() do { } while(0)
509 #endif
510
511 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
512 frequency threaded job scheduling. For almost all the purposes
513 tasklets are more than enough. F.e. all serial device BHs et
514 al. should be converted to tasklets, not to softirqs.
515 */
516
517 enum
518 {
519 HI_SOFTIRQ=0,
520 TIMER_SOFTIRQ,
521 NET_TX_SOFTIRQ,
522 NET_RX_SOFTIRQ,
523 BLOCK_SOFTIRQ,
524 IRQ_POLL_SOFTIRQ,
525 TASKLET_SOFTIRQ,
526 SCHED_SOFTIRQ,
527 HRTIMER_SOFTIRQ, /* Unused, but kept as tools rely on the
528 numbering. Sigh! */
529 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
530
531 NR_SOFTIRQS
532 };
533
534 #define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ))
535
536 /* map softirq index to softirq name. update 'softirq_to_name' in
537 * kernel/softirq.c when adding a new softirq.
538 */
539 extern const char * const softirq_to_name[NR_SOFTIRQS];
540
541 /* softirq mask and active fields moved to irq_cpustat_t in
542 * asm/hardirq.h to get better cache usage. KAO
543 */
544
545 struct softirq_action
546 {
547 void (*action)(struct softirq_action *);
548 };
549
550 asmlinkage void do_softirq(void);
551 asmlinkage void __do_softirq(void);
552
553 #ifdef __ARCH_HAS_DO_SOFTIRQ
554 void do_softirq_own_stack(void);
555 #else
do_softirq_own_stack(void)556 static inline void do_softirq_own_stack(void)
557 {
558 __do_softirq();
559 }
560 #endif
561
562 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
563 extern void softirq_init(void);
564 extern void __raise_softirq_irqoff(unsigned int nr);
565
566 extern void raise_softirq_irqoff(unsigned int nr);
567 extern void raise_softirq(unsigned int nr);
568
569 DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
570
this_cpu_ksoftirqd(void)571 static inline struct task_struct *this_cpu_ksoftirqd(void)
572 {
573 return this_cpu_read(ksoftirqd);
574 }
575
576 /* Tasklets --- multithreaded analogue of BHs.
577
578 Main feature differing them of generic softirqs: tasklet
579 is running only on one CPU simultaneously.
580
581 Main feature differing them of BHs: different tasklets
582 may be run simultaneously on different CPUs.
583
584 Properties:
585 * If tasklet_schedule() is called, then tasklet is guaranteed
586 to be executed on some cpu at least once after this.
587 * If the tasklet is already scheduled, but its execution is still not
588 started, it will be executed only once.
589 * If this tasklet is already running on another CPU (or schedule is called
590 from tasklet itself), it is rescheduled for later.
591 * Tasklet is strictly serialized wrt itself, but not
592 wrt another tasklets. If client needs some intertask synchronization,
593 he makes it with spinlocks.
594 */
595
596 struct tasklet_struct
597 {
598 struct tasklet_struct *next;
599 unsigned long state;
600 atomic_t count;
601 void (*func)(unsigned long);
602 unsigned long data;
603 };
604
605 #define DECLARE_TASKLET_OLD(name, _func) \
606 struct tasklet_struct name = { \
607 .count = ATOMIC_INIT(0), \
608 .func = _func, \
609 }
610
611 #define DECLARE_TASKLET_DISABLED_OLD(name, _func) \
612 struct tasklet_struct name = { \
613 .count = ATOMIC_INIT(1), \
614 .func = _func, \
615 }
616
617 enum
618 {
619 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
620 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
621 };
622
623 #ifdef CONFIG_SMP
tasklet_trylock(struct tasklet_struct * t)624 static inline int tasklet_trylock(struct tasklet_struct *t)
625 {
626 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
627 }
628
tasklet_unlock(struct tasklet_struct * t)629 static inline void tasklet_unlock(struct tasklet_struct *t)
630 {
631 smp_mb__before_atomic();
632 clear_bit(TASKLET_STATE_RUN, &(t)->state);
633 }
634
tasklet_unlock_wait(struct tasklet_struct * t)635 static inline void tasklet_unlock_wait(struct tasklet_struct *t)
636 {
637 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
638 }
639 #else
640 #define tasklet_trylock(t) 1
641 #define tasklet_unlock_wait(t) do { } while (0)
642 #define tasklet_unlock(t) do { } while (0)
643 #endif
644
645 extern void __tasklet_schedule(struct tasklet_struct *t);
646
tasklet_schedule(struct tasklet_struct * t)647 static inline void tasklet_schedule(struct tasklet_struct *t)
648 {
649 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
650 __tasklet_schedule(t);
651 }
652
653 extern void __tasklet_hi_schedule(struct tasklet_struct *t);
654
tasklet_hi_schedule(struct tasklet_struct * t)655 static inline void tasklet_hi_schedule(struct tasklet_struct *t)
656 {
657 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
658 __tasklet_hi_schedule(t);
659 }
660
tasklet_disable_nosync(struct tasklet_struct * t)661 static inline void tasklet_disable_nosync(struct tasklet_struct *t)
662 {
663 atomic_inc(&t->count);
664 smp_mb__after_atomic();
665 }
666
tasklet_disable(struct tasklet_struct * t)667 static inline void tasklet_disable(struct tasklet_struct *t)
668 {
669 tasklet_disable_nosync(t);
670 tasklet_unlock_wait(t);
671 smp_mb();
672 }
673
tasklet_enable(struct tasklet_struct * t)674 static inline void tasklet_enable(struct tasklet_struct *t)
675 {
676 smp_mb__before_atomic();
677 atomic_dec(&t->count);
678 }
679
680 extern void tasklet_kill(struct tasklet_struct *t);
681 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
682 extern void tasklet_init(struct tasklet_struct *t,
683 void (*func)(unsigned long), unsigned long data);
684
685 /*
686 * Autoprobing for irqs:
687 *
688 * probe_irq_on() and probe_irq_off() provide robust primitives
689 * for accurate IRQ probing during kernel initialization. They are
690 * reasonably simple to use, are not "fooled" by spurious interrupts,
691 * and, unlike other attempts at IRQ probing, they do not get hung on
692 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
693 *
694 * For reasonably foolproof probing, use them as follows:
695 *
696 * 1. clear and/or mask the device's internal interrupt.
697 * 2. sti();
698 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
699 * 4. enable the device and cause it to trigger an interrupt.
700 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
701 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
702 * 7. service the device to clear its pending interrupt.
703 * 8. loop again if paranoia is required.
704 *
705 * probe_irq_on() returns a mask of allocated irq's.
706 *
707 * probe_irq_off() takes the mask as a parameter,
708 * and returns the irq number which occurred,
709 * or zero if none occurred, or a negative irq number
710 * if more than one irq occurred.
711 */
712
713 #if !defined(CONFIG_GENERIC_IRQ_PROBE)
probe_irq_on(void)714 static inline unsigned long probe_irq_on(void)
715 {
716 return 0;
717 }
probe_irq_off(unsigned long val)718 static inline int probe_irq_off(unsigned long val)
719 {
720 return 0;
721 }
probe_irq_mask(unsigned long val)722 static inline unsigned int probe_irq_mask(unsigned long val)
723 {
724 return 0;
725 }
726 #else
727 extern unsigned long probe_irq_on(void); /* returns 0 on failure */
728 extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
729 extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
730 #endif
731
732 #ifdef CONFIG_PROC_FS
733 /* Initialize /proc/irq/ */
734 extern void init_irq_proc(void);
735 #else
init_irq_proc(void)736 static inline void init_irq_proc(void)
737 {
738 }
739 #endif
740
741 #ifdef CONFIG_IRQ_TIMINGS
742 void irq_timings_enable(void);
743 void irq_timings_disable(void);
744 u64 irq_timings_next_event(u64 now);
745 #endif
746
747 struct seq_file;
748 int show_interrupts(struct seq_file *p, void *v);
749 int arch_show_interrupts(struct seq_file *p, int prec);
750
751 extern int early_irq_init(void);
752 extern int arch_probe_nr_irqs(void);
753 extern int arch_early_irq_init(void);
754
755 /*
756 * We want to know which function is an entrypoint of a hardirq or a softirq.
757 */
758 #define __irq_entry __attribute__((__section__(".irqentry.text")))
759 #define __softirq_entry \
760 __attribute__((__section__(".softirqentry.text")))
761
762 #endif
763