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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* interrupt.h */
2#ifndef _LINUX_INTERRUPT_H
3#define _LINUX_INTERRUPT_H
4
Linus Torvalds1da177e2005-04-16 15:20:36 -07005#include <linux/kernel.h>
6#include <linux/linkage.h>
7#include <linux/bitops.h>
8#include <linux/preempt.h>
9#include <linux/cpumask.h>
Jan Beulich908dcec2006-06-23 02:06:00 -070010#include <linux/irqreturn.h>
Thomas Gleixnerdd3a1db2008-10-16 18:20:58 +020011#include <linux/irqnr.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/hardirq.h>
Ingo Molnarde30a2b2006-07-03 00:24:42 -070013#include <linux/irqflags.h>
David S. Miller54514a72008-09-23 22:15:57 -070014#include <linux/smp.h>
15#include <linux/percpu.h>
Peter Zijlstra9ba5f002009-07-22 14:18:35 +020016#include <linux/hrtimer.h>
Ingo Molnar0ebb26e2008-12-12 11:26:39 +010017
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <asm/atomic.h>
19#include <asm/ptrace.h>
20#include <asm/system.h>
21
Thomas Gleixner6e213612006-07-01 19:29:03 -070022/*
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 *
Thomas Gleixner6932bf32010-03-26 00:06:55 +000042 * IRQF_DISABLED - keep irqs disabled when calling the action handler.
43 * DEPRECATED. This flag is a NOOP and scheduled to be removed
Thomas Gleixner6e213612006-07-01 19:29:03 -070044 * 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
Thomas Gleixner950f4422007-02-16 01:27:24 -080048 * IRQF_PERCPU - Interrupt is per cpu
49 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
Bernhard Walled85a60d2007-05-08 00:35:24 -070050 * 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)
Thomas Gleixnerb25c3402009-08-13 12:17:22 +020053 * 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.
Ian Campbell685fd0b2010-07-29 11:16:32 +010056 * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend
57 *
Thomas Gleixner6e213612006-07-01 19:29:03 -070058 */
59#define IRQF_DISABLED 0x00000020
60#define IRQF_SAMPLE_RANDOM 0x00000040
61#define IRQF_SHARED 0x00000080
62#define IRQF_PROBE_SHARED 0x00000100
Ian Campbell685fd0b2010-07-29 11:16:32 +010063#define __IRQF_TIMER 0x00000200
Thomas Gleixner284c6682006-07-03 02:20:32 +020064#define IRQF_PERCPU 0x00000400
Thomas Gleixner950f4422007-02-16 01:27:24 -080065#define IRQF_NOBALANCING 0x00000800
Bernhard Walled85a60d2007-05-08 00:35:24 -070066#define IRQF_IRQPOLL 0x00001000
Thomas Gleixnerb25c3402009-08-13 12:17:22 +020067#define IRQF_ONESHOT 0x00002000
Ian Campbell685fd0b2010-07-29 11:16:32 +010068#define IRQF_NO_SUSPEND 0x00004000
69
70#define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND)
Thomas Gleixner6e213612006-07-01 19:29:03 -070071
Thomas Gleixner3aa551c2009-03-23 18:28:15 +010072/*
73 * Bits used by threaded handlers:
74 * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run
75 * IRQTF_DIED - handler thread died
Thomas Gleixnerf48fe812009-03-24 11:46:22 +010076 * IRQTF_WARNED - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed
Thomas Gleixner591d2fb2009-07-21 11:09:39 +020077 * IRQTF_AFFINITY - irq thread is requested to adjust affinity
Thomas Gleixner3aa551c2009-03-23 18:28:15 +010078 */
79enum {
80 IRQTF_RUNTHREAD,
81 IRQTF_DIED,
Thomas Gleixnerf48fe812009-03-24 11:46:22 +010082 IRQTF_WARNED,
Thomas Gleixner591d2fb2009-07-21 11:09:39 +020083 IRQTF_AFFINITY,
Thomas Gleixner3aa551c2009-03-23 18:28:15 +010084};
85
Randy Dunlapb4e6b092010-05-21 09:03:01 -070086/*
Marc Zyngierae731f82010-03-15 22:56:33 +000087 * These values can be returned by request_any_context_irq() and
88 * describe the context the interrupt will be run in.
89 *
90 * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
91 * IRQC_IS_NESTED - interrupt runs in a nested threaded context
92 */
93enum {
94 IRQC_IS_HARDIRQ = 0,
95 IRQC_IS_NESTED,
96};
97
David Howells7d12e782006-10-05 14:55:46 +010098typedef irqreturn_t (*irq_handler_t)(int, void *);
David Howellsda482792006-10-05 13:06:34 +010099
Thomas Gleixnera9d0a1a2009-03-03 16:58:16 +0100100/**
101 * struct irqaction - per interrupt action descriptor
102 * @handler: interrupt handler function
103 * @flags: flags (see IRQF_* above)
Thomas Gleixnera9d0a1a2009-03-03 16:58:16 +0100104 * @name: name of the device
105 * @dev_id: cookie to identify the device
106 * @next: pointer to the next irqaction for shared interrupts
107 * @irq: interrupt number
108 * @dir: pointer to the proc/irq/NN/name entry
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100109 * @thread_fn: interupt handler function for threaded interrupts
110 * @thread: thread pointer for threaded interrupts
111 * @thread_flags: flags related to @thread
Thomas Gleixnera9d0a1a2009-03-03 16:58:16 +0100112 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113struct irqaction {
David Howellsda482792006-10-05 13:06:34 +0100114 irq_handler_t handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 const char *name;
117 void *dev_id;
118 struct irqaction *next;
119 int irq;
120 struct proc_dir_entry *dir;
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100121 irq_handler_t thread_fn;
122 struct task_struct *thread;
123 unsigned long thread_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124};
125
David Howells7d12e782006-10-05 14:55:46 +0100126extern irqreturn_t no_action(int cpl, void *dev_id);
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100127
Thomas Gleixner3a381482009-03-24 20:27:39 +0100128#ifdef CONFIG_GENERIC_HARDIRQS
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100129extern int __must_check
130request_threaded_irq(unsigned int irq, irq_handler_t handler,
131 irq_handler_t thread_fn,
132 unsigned long flags, const char *name, void *dev);
133
134static inline int __must_check
135request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
136 const char *name, void *dev)
137{
138 return request_threaded_irq(irq, handler, NULL, flags, name, dev);
139}
140
Marc Zyngierae731f82010-03-15 22:56:33 +0000141extern int __must_check
142request_any_context_irq(unsigned int irq, irq_handler_t handler,
143 unsigned long flags, const char *name, void *dev_id);
144
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100145extern void exit_irq_thread(void);
146#else
Thomas Gleixner3a381482009-03-24 20:27:39 +0100147
148extern int __must_check
149request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
150 const char *name, void *dev);
151
Thomas Gleixnerde188362009-03-25 17:33:38 +0100152/*
153 * Special function to avoid ifdeffery in kernel/irq/devres.c which
154 * gets magically built by GENERIC_HARDIRQS=n architectures (sparc,
155 * m68k). I really love these $@%#!* obvious Makefile references:
156 * ../../../kernel/irq/devres.o
157 */
158static inline int __must_check
159request_threaded_irq(unsigned int irq, irq_handler_t handler,
160 irq_handler_t thread_fn,
161 unsigned long flags, const char *name, void *dev)
162{
163 return request_irq(irq, handler, flags, name, dev);
164}
165
Marc Zyngierae731f82010-03-15 22:56:33 +0000166static inline int __must_check
167request_any_context_irq(unsigned int irq, irq_handler_t handler,
168 unsigned long flags, const char *name, void *dev_id)
169{
170 return request_irq(irq, handler, flags, name, dev_id);
171}
172
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100173static inline void exit_irq_thread(void) { }
174#endif
175
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176extern void free_irq(unsigned int, void *);
177
Al Viro0af36782007-07-27 14:24:33 +0100178struct device;
179
Arjan van de Ven935bd5b2009-03-23 18:28:16 +0100180extern int __must_check
181devm_request_threaded_irq(struct device *dev, unsigned int irq,
182 irq_handler_t handler, irq_handler_t thread_fn,
183 unsigned long irqflags, const char *devname,
184 void *dev_id);
185
186static inline int __must_check
187devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
188 unsigned long irqflags, const char *devname, void *dev_id)
189{
190 return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
191 devname, dev_id);
192}
193
Tejun Heo9ac78492007-01-20 16:00:26 +0900194extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
195
Ingo Molnard7e96292006-07-03 00:24:27 -0700196/*
197 * On lockdep we dont want to enable hardirqs in hardirq
198 * context. Use local_irq_enable_in_hardirq() to annotate
199 * kernel code that has to do this nevertheless (pretty much
200 * the only valid case is for old/broken hardware that is
201 * insanely slow).
202 *
203 * NOTE: in theory this might break fragile code that relies
204 * on hardirq delivery - in practice we dont seem to have such
205 * places left. So the only effect should be slightly increased
206 * irqs-off latencies.
207 */
208#ifdef CONFIG_LOCKDEP
209# define local_irq_enable_in_hardirq() do { } while (0)
210#else
211# define local_irq_enable_in_hardirq() local_irq_enable()
212#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214extern void disable_irq_nosync(unsigned int irq);
215extern void disable_irq(unsigned int irq);
216extern void enable_irq(unsigned int irq);
Thomas Gleixnerba9a2332006-06-29 02:24:55 -0700217
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +0100218/* The following three functions are for the core kernel use only. */
Heiko Carstens5818a6e2009-06-11 21:59:21 +0200219#ifdef CONFIG_GENERIC_HARDIRQS
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +0100220extern void suspend_device_irqs(void);
221extern void resume_device_irqs(void);
222#ifdef CONFIG_PM_SLEEP
223extern int check_wakeup_irqs(void);
224#else
225static inline int check_wakeup_irqs(void) { return 0; }
226#endif
Heiko Carstens5818a6e2009-06-11 21:59:21 +0200227#else
228static inline void suspend_device_irqs(void) { };
229static inline void resume_device_irqs(void) { };
230static inline int check_wakeup_irqs(void) { return 0; }
231#endif
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +0100232
Russell Kingd7b90682008-04-17 07:46:24 +0200233#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
234
Rusty Russelld036e672009-01-01 10:12:26 +1030235extern cpumask_var_t irq_default_affinity;
Max Krasnyansky18404752008-05-29 11:02:52 -0700236
Rusty Russell0de26522008-12-13 21:20:26 +1030237extern int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask);
Russell Kingd7b90682008-04-17 07:46:24 +0200238extern int irq_can_set_affinity(unsigned int irq);
Max Krasnyansky18404752008-05-29 11:02:52 -0700239extern int irq_select_affinity(unsigned int irq);
Russell Kingd7b90682008-04-17 07:46:24 +0200240
Peter P Waskiewicz Jre7a297b2010-04-30 14:44:50 -0700241extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
Russell Kingd7b90682008-04-17 07:46:24 +0200242#else /* CONFIG_SMP */
243
Rusty Russell0de26522008-12-13 21:20:26 +1030244static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
Russell Kingd7b90682008-04-17 07:46:24 +0200245{
246 return -EINVAL;
247}
248
249static inline int irq_can_set_affinity(unsigned int irq)
250{
251 return 0;
252}
253
Max Krasnyansky18404752008-05-29 11:02:52 -0700254static inline int irq_select_affinity(unsigned int irq) { return 0; }
255
Peter P Waskiewicz Jre7a297b2010-04-30 14:44:50 -0700256static inline int irq_set_affinity_hint(unsigned int irq,
257 const struct cpumask *m)
258{
259 return -EINVAL;
260}
Russell Kingd7b90682008-04-17 07:46:24 +0200261#endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
262
Al Viroe9ed7e72007-07-21 23:29:12 +0100263#ifdef CONFIG_GENERIC_HARDIRQS
Ingo Molnarc01d4032006-07-03 00:24:27 -0700264/*
265 * Special lockdep variants of irq disabling/enabling.
266 * These should be used for locking constructs that
267 * know that a particular irq context which is disabled,
268 * and which is the only irq-context user of a lock,
269 * that it's safe to take the lock in the irq-disabled
270 * section without disabling hardirqs.
271 *
272 * On !CONFIG_LOCKDEP they are equivalent to the normal
273 * irq disable/enable methods.
274 */
275static inline void disable_irq_nosync_lockdep(unsigned int irq)
276{
277 disable_irq_nosync(irq);
278#ifdef CONFIG_LOCKDEP
279 local_irq_disable();
280#endif
281}
282
Arjan van de Vene8106b92006-09-29 02:01:08 -0700283static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
284{
285 disable_irq_nosync(irq);
286#ifdef CONFIG_LOCKDEP
287 local_irq_save(*flags);
288#endif
289}
290
Ingo Molnarc01d4032006-07-03 00:24:27 -0700291static inline void disable_irq_lockdep(unsigned int irq)
292{
293 disable_irq(irq);
294#ifdef CONFIG_LOCKDEP
295 local_irq_disable();
296#endif
297}
298
299static inline void enable_irq_lockdep(unsigned int irq)
300{
301#ifdef CONFIG_LOCKDEP
302 local_irq_enable();
303#endif
304 enable_irq(irq);
305}
306
Arjan van de Vene8106b92006-09-29 02:01:08 -0700307static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
308{
309#ifdef CONFIG_LOCKDEP
310 local_irq_restore(*flags);
311#endif
312 enable_irq(irq);
313}
314
Thomas Gleixnerba9a2332006-06-29 02:24:55 -0700315/* IRQ wakeup (PM) control: */
316extern int set_irq_wake(unsigned int irq, unsigned int on);
317
318static inline int enable_irq_wake(unsigned int irq)
319{
320 return set_irq_wake(irq, 1);
321}
322
323static inline int disable_irq_wake(unsigned int irq)
324{
325 return set_irq_wake(irq, 0);
326}
327
Ingo Molnarc01d4032006-07-03 00:24:27 -0700328#else /* !CONFIG_GENERIC_HARDIRQS */
329/*
330 * NOTE: non-genirq architectures, if they want to support the lock
331 * validator need to define the methods below in their asm/irq.h
332 * files, under an #ifdef CONFIG_LOCKDEP section.
333 */
Roman Zippelb3e2fd92007-05-01 22:32:42 +0200334#ifndef CONFIG_LOCKDEP
Ingo Molnarc01d4032006-07-03 00:24:27 -0700335# define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq)
Roman Zippelb3e2fd92007-05-01 22:32:42 +0200336# define disable_irq_nosync_lockdep_irqsave(irq, flags) \
337 disable_irq_nosync(irq)
Ingo Molnarc01d4032006-07-03 00:24:27 -0700338# define disable_irq_lockdep(irq) disable_irq(irq)
339# define enable_irq_lockdep(irq) enable_irq(irq)
Roman Zippelb3e2fd92007-05-01 22:32:42 +0200340# define enable_irq_lockdep_irqrestore(irq, flags) \
341 enable_irq(irq)
Ingo Molnarc01d4032006-07-03 00:24:27 -0700342# endif
343
Guennadi Liakhovetskiaa5346a2007-10-16 01:24:01 -0700344static inline int enable_irq_wake(unsigned int irq)
345{
346 return 0;
347}
348
349static inline int disable_irq_wake(unsigned int irq)
350{
351 return 0;
352}
Ingo Molnarc01d4032006-07-03 00:24:27 -0700353#endif /* CONFIG_GENERIC_HARDIRQS */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354
Andi Kleen3f744782005-09-12 18:49:24 +0200355#ifndef __ARCH_SET_SOFTIRQ_PENDING
356#define set_softirq_pending(x) (local_softirq_pending() = (x))
357#define or_softirq_pending(x) (local_softirq_pending() |= (x))
358#endif
359
Benjamin Herrenschmidt2d3fbbb2007-05-10 22:22:46 -0700360/* Some architectures might implement lazy enabling/disabling of
361 * interrupts. In some cases, such as stop_machine, we might want
362 * to ensure that after a local_irq_disable(), interrupts have
363 * really been disabled in hardware. Such architectures need to
364 * implement the following hook.
365 */
366#ifndef hard_irq_disable
367#define hard_irq_disable() do { } while(0)
368#endif
369
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
371 frequency threaded job scheduling. For almost all the purposes
372 tasklets are more than enough. F.e. all serial device BHs et
373 al. should be converted to tasklets, not to softirqs.
374 */
375
376enum
377{
378 HI_SOFTIRQ=0,
379 TIMER_SOFTIRQ,
380 NET_TX_SOFTIRQ,
381 NET_RX_SOFTIRQ,
Jens Axboeff856ba2006-01-09 16:02:34 +0100382 BLOCK_SOFTIRQ,
Jens Axboe5e605b62009-08-05 09:07:21 +0200383 BLOCK_IOPOLL_SOFTIRQ,
Christoph Lameterc9819f42006-12-10 02:20:25 -0800384 TASKLET_SOFTIRQ,
385 SCHED_SOFTIRQ,
Peter Zijlstraa6037b62009-01-05 11:28:22 +0100386 HRTIMER_SOFTIRQ,
387 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
Alexey Dobriyan978b0112008-09-06 20:04:36 +0200388
389 NR_SOFTIRQS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390};
391
Jason Baron5d592b42009-03-12 14:33:36 -0400392/* map softirq index to softirq name. update 'softirq_to_name' in
393 * kernel/softirq.c when adding a new softirq.
394 */
395extern char *softirq_to_name[NR_SOFTIRQS];
396
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397/* softirq mask and active fields moved to irq_cpustat_t in
398 * asm/hardirq.h to get better cache usage. KAO
399 */
400
401struct softirq_action
402{
403 void (*action)(struct softirq_action *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404};
405
406asmlinkage void do_softirq(void);
Adrian Bunkeb0f1c42008-04-29 00:59:12 -0700407asmlinkage void __do_softirq(void);
Carlos R. Mafra962cf362008-05-15 11:15:37 -0300408extern void open_softirq(int nr, void (*action)(struct softirq_action *));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409extern void softirq_init(void);
Andi Kleen3f744782005-09-12 18:49:24 +0200410#define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)
Harvey Harrisonb3c97522008-02-13 15:03:15 -0800411extern void raise_softirq_irqoff(unsigned int nr);
412extern void raise_softirq(unsigned int nr);
Peter Zijlstra7f1e2ca2009-03-13 12:21:27 +0100413extern void wakeup_softirqd(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414
David S. Miller54514a72008-09-23 22:15:57 -0700415/* This is the worklist that queues up per-cpu softirq work.
416 *
417 * send_remote_sendirq() adds work to these lists, and
418 * the softirq handler itself dequeues from them. The queues
419 * are protected by disabling local cpu interrupts and they must
420 * only be accessed by the local cpu that they are for.
421 */
422DECLARE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list);
423
424/* Try to send a softirq to a remote cpu. If this cannot be done, the
425 * work will be queued to the local cpu.
426 */
427extern void send_remote_softirq(struct call_single_data *cp, int cpu, int softirq);
428
429/* Like send_remote_softirq(), but the caller must disable local cpu interrupts
430 * and compute the current cpu, passed in as 'this_cpu'.
431 */
432extern void __send_remote_softirq(struct call_single_data *cp, int cpu,
433 int this_cpu, int softirq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434
435/* Tasklets --- multithreaded analogue of BHs.
436
437 Main feature differing them of generic softirqs: tasklet
438 is running only on one CPU simultaneously.
439
440 Main feature differing them of BHs: different tasklets
441 may be run simultaneously on different CPUs.
442
443 Properties:
444 * If tasklet_schedule() is called, then tasklet is guaranteed
445 to be executed on some cpu at least once after this.
446 * If the tasklet is already scheduled, but its excecution is still not
447 started, it will be executed only once.
448 * If this tasklet is already running on another CPU (or schedule is called
449 from tasklet itself), it is rescheduled for later.
450 * Tasklet is strictly serialized wrt itself, but not
451 wrt another tasklets. If client needs some intertask synchronization,
452 he makes it with spinlocks.
453 */
454
455struct tasklet_struct
456{
457 struct tasklet_struct *next;
458 unsigned long state;
459 atomic_t count;
460 void (*func)(unsigned long);
461 unsigned long data;
462};
463
464#define DECLARE_TASKLET(name, func, data) \
465struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
466
467#define DECLARE_TASKLET_DISABLED(name, func, data) \
468struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
469
470
471enum
472{
473 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
474 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
475};
476
477#ifdef CONFIG_SMP
478static inline int tasklet_trylock(struct tasklet_struct *t)
479{
480 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
481}
482
483static inline void tasklet_unlock(struct tasklet_struct *t)
484{
485 smp_mb__before_clear_bit();
486 clear_bit(TASKLET_STATE_RUN, &(t)->state);
487}
488
489static inline void tasklet_unlock_wait(struct tasklet_struct *t)
490{
491 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
492}
493#else
494#define tasklet_trylock(t) 1
495#define tasklet_unlock_wait(t) do { } while (0)
496#define tasklet_unlock(t) do { } while (0)
497#endif
498
Harvey Harrisonb3c97522008-02-13 15:03:15 -0800499extern void __tasklet_schedule(struct tasklet_struct *t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500
501static inline void tasklet_schedule(struct tasklet_struct *t)
502{
503 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
504 __tasklet_schedule(t);
505}
506
Harvey Harrisonb3c97522008-02-13 15:03:15 -0800507extern void __tasklet_hi_schedule(struct tasklet_struct *t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508
509static inline void tasklet_hi_schedule(struct tasklet_struct *t)
510{
511 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
512 __tasklet_hi_schedule(t);
513}
514
Vegard Nossum7c692cb2008-05-21 22:53:13 +0200515extern void __tasklet_hi_schedule_first(struct tasklet_struct *t);
516
517/*
518 * This version avoids touching any other tasklets. Needed for kmemcheck
519 * in order not to take any page faults while enqueueing this tasklet;
520 * consider VERY carefully whether you really need this or
521 * tasklet_hi_schedule()...
522 */
523static inline void tasklet_hi_schedule_first(struct tasklet_struct *t)
524{
525 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
526 __tasklet_hi_schedule_first(t);
527}
528
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
530static inline void tasklet_disable_nosync(struct tasklet_struct *t)
531{
532 atomic_inc(&t->count);
533 smp_mb__after_atomic_inc();
534}
535
536static inline void tasklet_disable(struct tasklet_struct *t)
537{
538 tasklet_disable_nosync(t);
539 tasklet_unlock_wait(t);
540 smp_mb();
541}
542
543static inline void tasklet_enable(struct tasklet_struct *t)
544{
545 smp_mb__before_atomic_dec();
546 atomic_dec(&t->count);
547}
548
549static inline void tasklet_hi_enable(struct tasklet_struct *t)
550{
551 smp_mb__before_atomic_dec();
552 atomic_dec(&t->count);
553}
554
555extern void tasklet_kill(struct tasklet_struct *t);
556extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
557extern void tasklet_init(struct tasklet_struct *t,
558 void (*func)(unsigned long), unsigned long data);
559
Peter Zijlstra9ba5f002009-07-22 14:18:35 +0200560struct tasklet_hrtimer {
561 struct hrtimer timer;
562 struct tasklet_struct tasklet;
563 enum hrtimer_restart (*function)(struct hrtimer *);
564};
565
566extern void
567tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer,
568 enum hrtimer_restart (*function)(struct hrtimer *),
569 clockid_t which_clock, enum hrtimer_mode mode);
570
571static inline
572int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time,
573 const enum hrtimer_mode mode)
574{
575 return hrtimer_start(&ttimer->timer, time, mode);
576}
577
578static inline
579void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
580{
581 hrtimer_cancel(&ttimer->timer);
582 tasklet_kill(&ttimer->tasklet);
583}
584
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585/*
586 * Autoprobing for irqs:
587 *
588 * probe_irq_on() and probe_irq_off() provide robust primitives
589 * for accurate IRQ probing during kernel initialization. They are
590 * reasonably simple to use, are not "fooled" by spurious interrupts,
591 * and, unlike other attempts at IRQ probing, they do not get hung on
592 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
593 *
594 * For reasonably foolproof probing, use them as follows:
595 *
596 * 1. clear and/or mask the device's internal interrupt.
597 * 2. sti();
598 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
599 * 4. enable the device and cause it to trigger an interrupt.
600 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
601 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
602 * 7. service the device to clear its pending interrupt.
603 * 8. loop again if paranoia is required.
604 *
605 * probe_irq_on() returns a mask of allocated irq's.
606 *
607 * probe_irq_off() takes the mask as a parameter,
608 * and returns the irq number which occurred,
609 * or zero if none occurred, or a negative irq number
610 * if more than one irq occurred.
611 */
612
613#if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
614static inline unsigned long probe_irq_on(void)
615{
616 return 0;
617}
618static inline int probe_irq_off(unsigned long val)
619{
620 return 0;
621}
622static inline unsigned int probe_irq_mask(unsigned long val)
623{
624 return 0;
625}
626#else
627extern unsigned long probe_irq_on(void); /* returns 0 on failure */
628extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
629extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
630#endif
631
Andrew Morton6168a702007-02-17 21:22:39 -0800632#ifdef CONFIG_PROC_FS
633/* Initialize /proc/irq/ */
634extern void init_irq_proc(void);
635#else
636static inline void init_irq_proc(void)
637{
638}
639#endif
640
Alexey Dobriyand43c36d2009-10-07 17:09:06 +0400641struct seq_file;
Adrian Bunkf74596d2008-02-06 01:36:35 -0800642int show_interrupts(struct seq_file *p, void *v);
643
Yinghai Lu43a25632008-12-28 16:01:13 -0800644struct irq_desc;
645
646extern int early_irq_init(void);
Yinghai Lu4a046d12009-01-12 17:39:24 -0800647extern int arch_probe_nr_irqs(void);
Yinghai Lu43a25632008-12-28 16:01:13 -0800648extern int arch_early_irq_init(void);
Yinghai Lu85ac16d2009-04-27 18:00:38 -0700649extern int arch_init_chip_data(struct irq_desc *desc, int node);
Yinghai Lu43a25632008-12-28 16:01:13 -0800650
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651#endif