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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>
Lai Jiangshan2bf21602010-08-23 18:42:48 +090021#include <trace/events/irq.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022
Thomas Gleixner6e213612006-07-01 19:29:03 -070023/*
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 *
Thomas Gleixner6932bf32010-03-26 00:06:55 +000043 * IRQF_DISABLED - keep irqs disabled when calling the action handler.
44 * DEPRECATED. This flag is a NOOP and scheduled to be removed
Thomas Gleixner6e213612006-07-01 19:29:03 -070045 * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
46 * IRQF_SHARED - allow sharing the irq among several devices
47 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
48 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
Thomas Gleixner950f4422007-02-16 01:27:24 -080049 * IRQF_PERCPU - Interrupt is per cpu
50 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
Bernhard Walled85a60d2007-05-08 00:35:24 -070051 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
52 * registered first in an shared interrupt is considered for
53 * performance reasons)
Thomas Gleixnerb25c3402009-08-13 12:17:22 +020054 * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
55 * Used by threaded interrupts which need to keep the
56 * irq line disabled until the threaded handler has been run.
Ian Campbell685fd0b2010-07-29 11:16:32 +010057 * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend
58 *
Thomas Gleixner6e213612006-07-01 19:29:03 -070059 */
60#define IRQF_DISABLED 0x00000020
61#define IRQF_SAMPLE_RANDOM 0x00000040
62#define IRQF_SHARED 0x00000080
63#define IRQF_PROBE_SHARED 0x00000100
Ian Campbell685fd0b2010-07-29 11:16:32 +010064#define __IRQF_TIMER 0x00000200
Thomas Gleixner284c6682006-07-03 02:20:32 +020065#define IRQF_PERCPU 0x00000400
Thomas Gleixner950f4422007-02-16 01:27:24 -080066#define IRQF_NOBALANCING 0x00000800
Bernhard Walled85a60d2007-05-08 00:35:24 -070067#define IRQF_IRQPOLL 0x00001000
Thomas Gleixnerb25c3402009-08-13 12:17:22 +020068#define IRQF_ONESHOT 0x00002000
Ian Campbell685fd0b2010-07-29 11:16:32 +010069#define IRQF_NO_SUSPEND 0x00004000
70
71#define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND)
Thomas Gleixner6e213612006-07-01 19:29:03 -070072
Thomas Gleixner3aa551c2009-03-23 18:28:15 +010073/*
74 * Bits used by threaded handlers:
75 * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run
76 * IRQTF_DIED - handler thread died
Thomas Gleixnerf48fe812009-03-24 11:46:22 +010077 * IRQTF_WARNED - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed
Thomas Gleixner591d2fb2009-07-21 11:09:39 +020078 * IRQTF_AFFINITY - irq thread is requested to adjust affinity
Thomas Gleixner3aa551c2009-03-23 18:28:15 +010079 */
80enum {
81 IRQTF_RUNTHREAD,
82 IRQTF_DIED,
Thomas Gleixnerf48fe812009-03-24 11:46:22 +010083 IRQTF_WARNED,
Thomas Gleixner591d2fb2009-07-21 11:09:39 +020084 IRQTF_AFFINITY,
Thomas Gleixner3aa551c2009-03-23 18:28:15 +010085};
86
Randy Dunlapb4e6b092010-05-21 09:03:01 -070087/*
Marc Zyngierae731f82010-03-15 22:56:33 +000088 * These values can be returned by request_any_context_irq() and
89 * describe the context the interrupt will be run in.
90 *
91 * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
92 * IRQC_IS_NESTED - interrupt runs in a nested threaded context
93 */
94enum {
95 IRQC_IS_HARDIRQ = 0,
96 IRQC_IS_NESTED,
97};
98
David Howells7d12e782006-10-05 14:55:46 +010099typedef irqreturn_t (*irq_handler_t)(int, void *);
David Howellsda482792006-10-05 13:06:34 +0100100
Thomas Gleixnera9d0a1a2009-03-03 16:58:16 +0100101/**
102 * struct irqaction - per interrupt action descriptor
103 * @handler: interrupt handler function
104 * @flags: flags (see IRQF_* above)
Thomas Gleixnera9d0a1a2009-03-03 16:58:16 +0100105 * @name: name of the device
106 * @dev_id: cookie to identify the device
107 * @next: pointer to the next irqaction for shared interrupts
108 * @irq: interrupt number
109 * @dir: pointer to the proc/irq/NN/name entry
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100110 * @thread_fn: interupt handler function for threaded interrupts
111 * @thread: thread pointer for threaded interrupts
112 * @thread_flags: flags related to @thread
Thomas Gleixnera9d0a1a2009-03-03 16:58:16 +0100113 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114struct irqaction {
David Howellsda482792006-10-05 13:06:34 +0100115 irq_handler_t handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 const char *name;
118 void *dev_id;
119 struct irqaction *next;
120 int irq;
121 struct proc_dir_entry *dir;
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100122 irq_handler_t thread_fn;
123 struct task_struct *thread;
124 unsigned long thread_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125};
126
David Howells7d12e782006-10-05 14:55:46 +0100127extern irqreturn_t no_action(int cpl, void *dev_id);
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100128
Thomas Gleixner3a381482009-03-24 20:27:39 +0100129#ifdef CONFIG_GENERIC_HARDIRQS
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100130extern int __must_check
131request_threaded_irq(unsigned int irq, irq_handler_t handler,
132 irq_handler_t thread_fn,
133 unsigned long flags, const char *name, void *dev);
134
135static inline int __must_check
136request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
137 const char *name, void *dev)
138{
139 return request_threaded_irq(irq, handler, NULL, flags, name, dev);
140}
141
Marc Zyngierae731f82010-03-15 22:56:33 +0000142extern int __must_check
143request_any_context_irq(unsigned int irq, irq_handler_t handler,
144 unsigned long flags, const char *name, void *dev_id);
145
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100146extern void exit_irq_thread(void);
147#else
Thomas Gleixner3a381482009-03-24 20:27:39 +0100148
149extern int __must_check
150request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
151 const char *name, void *dev);
152
Thomas Gleixnerde188362009-03-25 17:33:38 +0100153/*
154 * Special function to avoid ifdeffery in kernel/irq/devres.c which
155 * gets magically built by GENERIC_HARDIRQS=n architectures (sparc,
156 * m68k). I really love these $@%#!* obvious Makefile references:
157 * ../../../kernel/irq/devres.o
158 */
159static inline int __must_check
160request_threaded_irq(unsigned int irq, irq_handler_t handler,
161 irq_handler_t thread_fn,
162 unsigned long flags, const char *name, void *dev)
163{
164 return request_irq(irq, handler, flags, name, dev);
165}
166
Marc Zyngierae731f82010-03-15 22:56:33 +0000167static inline int __must_check
168request_any_context_irq(unsigned int irq, irq_handler_t handler,
169 unsigned long flags, const char *name, void *dev_id)
170{
171 return request_irq(irq, handler, flags, name, dev_id);
172}
173
Thomas Gleixner3aa551c2009-03-23 18:28:15 +0100174static inline void exit_irq_thread(void) { }
175#endif
176
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177extern void free_irq(unsigned int, void *);
178
Al Viro0af36782007-07-27 14:24:33 +0100179struct device;
180
Arjan van de Ven935bd5b2009-03-23 18:28:16 +0100181extern int __must_check
182devm_request_threaded_irq(struct device *dev, unsigned int irq,
183 irq_handler_t handler, irq_handler_t thread_fn,
184 unsigned long irqflags, const char *devname,
185 void *dev_id);
186
187static inline int __must_check
188devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
189 unsigned long irqflags, const char *devname, void *dev_id)
190{
191 return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
192 devname, dev_id);
193}
194
Tejun Heo9ac78492007-01-20 16:00:26 +0900195extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
196
Ingo Molnard7e96292006-07-03 00:24:27 -0700197/*
198 * On lockdep we dont want to enable hardirqs in hardirq
199 * context. Use local_irq_enable_in_hardirq() to annotate
200 * kernel code that has to do this nevertheless (pretty much
201 * the only valid case is for old/broken hardware that is
202 * insanely slow).
203 *
204 * NOTE: in theory this might break fragile code that relies
205 * on hardirq delivery - in practice we dont seem to have such
206 * places left. So the only effect should be slightly increased
207 * irqs-off latencies.
208 */
209#ifdef CONFIG_LOCKDEP
210# define local_irq_enable_in_hardirq() do { } while (0)
211#else
212# define local_irq_enable_in_hardirq() local_irq_enable()
213#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215extern void disable_irq_nosync(unsigned int irq);
216extern void disable_irq(unsigned int irq);
217extern void enable_irq(unsigned int irq);
Thomas Gleixnerba9a2332006-06-29 02:24:55 -0700218
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +0100219/* The following three functions are for the core kernel use only. */
Heiko Carstens5818a6e2009-06-11 21:59:21 +0200220#ifdef CONFIG_GENERIC_HARDIRQS
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +0100221extern void suspend_device_irqs(void);
222extern void resume_device_irqs(void);
223#ifdef CONFIG_PM_SLEEP
224extern int check_wakeup_irqs(void);
225#else
226static inline int check_wakeup_irqs(void) { return 0; }
227#endif
Heiko Carstens5818a6e2009-06-11 21:59:21 +0200228#else
229static inline void suspend_device_irqs(void) { };
230static inline void resume_device_irqs(void) { };
231static inline int check_wakeup_irqs(void) { return 0; }
232#endif
Rafael J. Wysocki0a0c5162009-03-16 22:33:49 +0100233
Russell Kingd7b90682008-04-17 07:46:24 +0200234#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
235
Rusty Russelld036e672009-01-01 10:12:26 +1030236extern cpumask_var_t irq_default_affinity;
Max Krasnyansky18404752008-05-29 11:02:52 -0700237
Rusty Russell0de26522008-12-13 21:20:26 +1030238extern int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask);
Russell Kingd7b90682008-04-17 07:46:24 +0200239extern int irq_can_set_affinity(unsigned int irq);
Max Krasnyansky18404752008-05-29 11:02:52 -0700240extern int irq_select_affinity(unsigned int irq);
Russell Kingd7b90682008-04-17 07:46:24 +0200241
Peter P Waskiewicz Jre7a297b2010-04-30 14:44:50 -0700242extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
Russell Kingd7b90682008-04-17 07:46:24 +0200243#else /* CONFIG_SMP */
244
Rusty Russell0de26522008-12-13 21:20:26 +1030245static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
Russell Kingd7b90682008-04-17 07:46:24 +0200246{
247 return -EINVAL;
248}
249
250static inline int irq_can_set_affinity(unsigned int irq)
251{
252 return 0;
253}
254
Max Krasnyansky18404752008-05-29 11:02:52 -0700255static inline int irq_select_affinity(unsigned int irq) { return 0; }
256
Peter P Waskiewicz Jre7a297b2010-04-30 14:44:50 -0700257static inline int irq_set_affinity_hint(unsigned int irq,
258 const struct cpumask *m)
259{
260 return -EINVAL;
261}
Russell Kingd7b90682008-04-17 07:46:24 +0200262#endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
263
Al Viroe9ed7e72007-07-21 23:29:12 +0100264#ifdef CONFIG_GENERIC_HARDIRQS
Ingo Molnarc01d4032006-07-03 00:24:27 -0700265/*
266 * Special lockdep variants of irq disabling/enabling.
267 * These should be used for locking constructs that
268 * know that a particular irq context which is disabled,
269 * and which is the only irq-context user of a lock,
270 * that it's safe to take the lock in the irq-disabled
271 * section without disabling hardirqs.
272 *
273 * On !CONFIG_LOCKDEP they are equivalent to the normal
274 * irq disable/enable methods.
275 */
276static inline void disable_irq_nosync_lockdep(unsigned int irq)
277{
278 disable_irq_nosync(irq);
279#ifdef CONFIG_LOCKDEP
280 local_irq_disable();
281#endif
282}
283
Arjan van de Vene8106b92006-09-29 02:01:08 -0700284static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
285{
286 disable_irq_nosync(irq);
287#ifdef CONFIG_LOCKDEP
288 local_irq_save(*flags);
289#endif
290}
291
Ingo Molnarc01d4032006-07-03 00:24:27 -0700292static inline void disable_irq_lockdep(unsigned int irq)
293{
294 disable_irq(irq);
295#ifdef CONFIG_LOCKDEP
296 local_irq_disable();
297#endif
298}
299
300static inline void enable_irq_lockdep(unsigned int irq)
301{
302#ifdef CONFIG_LOCKDEP
303 local_irq_enable();
304#endif
305 enable_irq(irq);
306}
307
Arjan van de Vene8106b92006-09-29 02:01:08 -0700308static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
309{
310#ifdef CONFIG_LOCKDEP
311 local_irq_restore(*flags);
312#endif
313 enable_irq(irq);
314}
315
Thomas Gleixnerba9a2332006-06-29 02:24:55 -0700316/* IRQ wakeup (PM) control: */
317extern int set_irq_wake(unsigned int irq, unsigned int on);
318
319static inline int enable_irq_wake(unsigned int irq)
320{
321 return set_irq_wake(irq, 1);
322}
323
324static inline int disable_irq_wake(unsigned int irq)
325{
326 return set_irq_wake(irq, 0);
327}
328
Ingo Molnarc01d4032006-07-03 00:24:27 -0700329#else /* !CONFIG_GENERIC_HARDIRQS */
330/*
331 * NOTE: non-genirq architectures, if they want to support the lock
332 * validator need to define the methods below in their asm/irq.h
333 * files, under an #ifdef CONFIG_LOCKDEP section.
334 */
Roman Zippelb3e2fd92007-05-01 22:32:42 +0200335#ifndef CONFIG_LOCKDEP
Ingo Molnarc01d4032006-07-03 00:24:27 -0700336# define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq)
Roman Zippelb3e2fd92007-05-01 22:32:42 +0200337# define disable_irq_nosync_lockdep_irqsave(irq, flags) \
338 disable_irq_nosync(irq)
Ingo Molnarc01d4032006-07-03 00:24:27 -0700339# define disable_irq_lockdep(irq) disable_irq(irq)
340# define enable_irq_lockdep(irq) enable_irq(irq)
Roman Zippelb3e2fd92007-05-01 22:32:42 +0200341# define enable_irq_lockdep_irqrestore(irq, flags) \
342 enable_irq(irq)
Ingo Molnarc01d4032006-07-03 00:24:27 -0700343# endif
344
Guennadi Liakhovetskiaa5346a2007-10-16 01:24:01 -0700345static inline int enable_irq_wake(unsigned int irq)
346{
347 return 0;
348}
349
350static inline int disable_irq_wake(unsigned int irq)
351{
352 return 0;
353}
Ingo Molnarc01d4032006-07-03 00:24:27 -0700354#endif /* CONFIG_GENERIC_HARDIRQS */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355
Andi Kleen3f744782005-09-12 18:49:24 +0200356#ifndef __ARCH_SET_SOFTIRQ_PENDING
357#define set_softirq_pending(x) (local_softirq_pending() = (x))
358#define or_softirq_pending(x) (local_softirq_pending() |= (x))
359#endif
360
Benjamin Herrenschmidt2d3fbbb2007-05-10 22:22:46 -0700361/* Some architectures might implement lazy enabling/disabling of
362 * interrupts. In some cases, such as stop_machine, we might want
363 * to ensure that after a local_irq_disable(), interrupts have
364 * really been disabled in hardware. Such architectures need to
365 * implement the following hook.
366 */
367#ifndef hard_irq_disable
368#define hard_irq_disable() do { } while(0)
369#endif
370
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
372 frequency threaded job scheduling. For almost all the purposes
373 tasklets are more than enough. F.e. all serial device BHs et
374 al. should be converted to tasklets, not to softirqs.
375 */
376
377enum
378{
379 HI_SOFTIRQ=0,
380 TIMER_SOFTIRQ,
381 NET_TX_SOFTIRQ,
382 NET_RX_SOFTIRQ,
Jens Axboeff856ba2006-01-09 16:02:34 +0100383 BLOCK_SOFTIRQ,
Jens Axboe5e605b62009-08-05 09:07:21 +0200384 BLOCK_IOPOLL_SOFTIRQ,
Christoph Lameterc9819f42006-12-10 02:20:25 -0800385 TASKLET_SOFTIRQ,
386 SCHED_SOFTIRQ,
Peter Zijlstraa6037b62009-01-05 11:28:22 +0100387 HRTIMER_SOFTIRQ,
388 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
Alexey Dobriyan978b0112008-09-06 20:04:36 +0200389
390 NR_SOFTIRQS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391};
392
Jason Baron5d592b42009-03-12 14:33:36 -0400393/* map softirq index to softirq name. update 'softirq_to_name' in
394 * kernel/softirq.c when adding a new softirq.
395 */
396extern char *softirq_to_name[NR_SOFTIRQS];
397
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398/* softirq mask and active fields moved to irq_cpustat_t in
399 * asm/hardirq.h to get better cache usage. KAO
400 */
401
402struct softirq_action
403{
404 void (*action)(struct softirq_action *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405};
406
407asmlinkage void do_softirq(void);
Adrian Bunkeb0f1c42008-04-29 00:59:12 -0700408asmlinkage void __do_softirq(void);
Carlos R. Mafra962cf362008-05-15 11:15:37 -0300409extern void open_softirq(int nr, void (*action)(struct softirq_action *));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410extern void softirq_init(void);
Lai Jiangshan2bf21602010-08-23 18:42:48 +0900411static inline void __raise_softirq_irqoff(unsigned int nr)
412{
Thomas Gleixnerf4bc6bb2010-10-19 15:00:13 +0200413 trace_softirq_raise(nr);
Lai Jiangshan2bf21602010-08-23 18:42:48 +0900414 or_softirq_pending(1UL << nr);
415}
416
Harvey Harrisonb3c97522008-02-13 15:03:15 -0800417extern void raise_softirq_irqoff(unsigned int nr);
418extern void raise_softirq(unsigned int nr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419
David S. Miller54514a72008-09-23 22:15:57 -0700420/* This is the worklist that queues up per-cpu softirq work.
421 *
422 * send_remote_sendirq() adds work to these lists, and
423 * the softirq handler itself dequeues from them. The queues
424 * are protected by disabling local cpu interrupts and they must
425 * only be accessed by the local cpu that they are for.
426 */
427DECLARE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list);
428
429/* Try to send a softirq to a remote cpu. If this cannot be done, the
430 * work will be queued to the local cpu.
431 */
432extern void send_remote_softirq(struct call_single_data *cp, int cpu, int softirq);
433
434/* Like send_remote_softirq(), but the caller must disable local cpu interrupts
435 * and compute the current cpu, passed in as 'this_cpu'.
436 */
437extern void __send_remote_softirq(struct call_single_data *cp, int cpu,
438 int this_cpu, int softirq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439
440/* Tasklets --- multithreaded analogue of BHs.
441
442 Main feature differing them of generic softirqs: tasklet
443 is running only on one CPU simultaneously.
444
445 Main feature differing them of BHs: different tasklets
446 may be run simultaneously on different CPUs.
447
448 Properties:
449 * If tasklet_schedule() is called, then tasklet is guaranteed
450 to be executed on some cpu at least once after this.
451 * If the tasklet is already scheduled, but its excecution is still not
452 started, it will be executed only once.
453 * If this tasklet is already running on another CPU (or schedule is called
454 from tasklet itself), it is rescheduled for later.
455 * Tasklet is strictly serialized wrt itself, but not
456 wrt another tasklets. If client needs some intertask synchronization,
457 he makes it with spinlocks.
458 */
459
460struct tasklet_struct
461{
462 struct tasklet_struct *next;
463 unsigned long state;
464 atomic_t count;
465 void (*func)(unsigned long);
466 unsigned long data;
467};
468
469#define DECLARE_TASKLET(name, func, data) \
470struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
471
472#define DECLARE_TASKLET_DISABLED(name, func, data) \
473struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
474
475
476enum
477{
478 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
479 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
480};
481
482#ifdef CONFIG_SMP
483static inline int tasklet_trylock(struct tasklet_struct *t)
484{
485 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
486}
487
488static inline void tasklet_unlock(struct tasklet_struct *t)
489{
490 smp_mb__before_clear_bit();
491 clear_bit(TASKLET_STATE_RUN, &(t)->state);
492}
493
494static inline void tasklet_unlock_wait(struct tasklet_struct *t)
495{
496 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
497}
498#else
499#define tasklet_trylock(t) 1
500#define tasklet_unlock_wait(t) do { } while (0)
501#define tasklet_unlock(t) do { } while (0)
502#endif
503
Harvey Harrisonb3c97522008-02-13 15:03:15 -0800504extern void __tasklet_schedule(struct tasklet_struct *t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505
506static inline void tasklet_schedule(struct tasklet_struct *t)
507{
508 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
509 __tasklet_schedule(t);
510}
511
Harvey Harrisonb3c97522008-02-13 15:03:15 -0800512extern void __tasklet_hi_schedule(struct tasklet_struct *t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513
514static inline void tasklet_hi_schedule(struct tasklet_struct *t)
515{
516 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
517 __tasklet_hi_schedule(t);
518}
519
Vegard Nossum7c692cb2008-05-21 22:53:13 +0200520extern void __tasklet_hi_schedule_first(struct tasklet_struct *t);
521
522/*
523 * This version avoids touching any other tasklets. Needed for kmemcheck
524 * in order not to take any page faults while enqueueing this tasklet;
525 * consider VERY carefully whether you really need this or
526 * tasklet_hi_schedule()...
527 */
528static inline void tasklet_hi_schedule_first(struct tasklet_struct *t)
529{
530 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
531 __tasklet_hi_schedule_first(t);
532}
533
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534
535static inline void tasklet_disable_nosync(struct tasklet_struct *t)
536{
537 atomic_inc(&t->count);
538 smp_mb__after_atomic_inc();
539}
540
541static inline void tasklet_disable(struct tasklet_struct *t)
542{
543 tasklet_disable_nosync(t);
544 tasklet_unlock_wait(t);
545 smp_mb();
546}
547
548static inline void tasklet_enable(struct tasklet_struct *t)
549{
550 smp_mb__before_atomic_dec();
551 atomic_dec(&t->count);
552}
553
554static inline void tasklet_hi_enable(struct tasklet_struct *t)
555{
556 smp_mb__before_atomic_dec();
557 atomic_dec(&t->count);
558}
559
560extern void tasklet_kill(struct tasklet_struct *t);
561extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
562extern void tasklet_init(struct tasklet_struct *t,
563 void (*func)(unsigned long), unsigned long data);
564
Peter Zijlstra9ba5f002009-07-22 14:18:35 +0200565struct tasklet_hrtimer {
566 struct hrtimer timer;
567 struct tasklet_struct tasklet;
568 enum hrtimer_restart (*function)(struct hrtimer *);
569};
570
571extern void
572tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer,
573 enum hrtimer_restart (*function)(struct hrtimer *),
574 clockid_t which_clock, enum hrtimer_mode mode);
575
576static inline
577int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time,
578 const enum hrtimer_mode mode)
579{
580 return hrtimer_start(&ttimer->timer, time, mode);
581}
582
583static inline
584void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
585{
586 hrtimer_cancel(&ttimer->timer);
587 tasklet_kill(&ttimer->tasklet);
588}
589
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590/*
591 * Autoprobing for irqs:
592 *
593 * probe_irq_on() and probe_irq_off() provide robust primitives
594 * for accurate IRQ probing during kernel initialization. They are
595 * reasonably simple to use, are not "fooled" by spurious interrupts,
596 * and, unlike other attempts at IRQ probing, they do not get hung on
597 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
598 *
599 * For reasonably foolproof probing, use them as follows:
600 *
601 * 1. clear and/or mask the device's internal interrupt.
602 * 2. sti();
603 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
604 * 4. enable the device and cause it to trigger an interrupt.
605 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
606 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
607 * 7. service the device to clear its pending interrupt.
608 * 8. loop again if paranoia is required.
609 *
610 * probe_irq_on() returns a mask of allocated irq's.
611 *
612 * probe_irq_off() takes the mask as a parameter,
613 * and returns the irq number which occurred,
614 * or zero if none occurred, or a negative irq number
615 * if more than one irq occurred.
616 */
617
618#if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
619static inline unsigned long probe_irq_on(void)
620{
621 return 0;
622}
623static inline int probe_irq_off(unsigned long val)
624{
625 return 0;
626}
627static inline unsigned int probe_irq_mask(unsigned long val)
628{
629 return 0;
630}
631#else
632extern unsigned long probe_irq_on(void); /* returns 0 on failure */
633extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
634extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
635#endif
636
Andrew Morton6168a702007-02-17 21:22:39 -0800637#ifdef CONFIG_PROC_FS
638/* Initialize /proc/irq/ */
639extern void init_irq_proc(void);
640#else
641static inline void init_irq_proc(void)
642{
643}
644#endif
645
Alexey Dobriyand43c36d2009-10-07 17:09:06 +0400646struct seq_file;
Adrian Bunkf74596d2008-02-06 01:36:35 -0800647int show_interrupts(struct seq_file *p, void *v);
648
Yinghai Lu43a25632008-12-28 16:01:13 -0800649extern int early_irq_init(void);
Yinghai Lu4a046d12009-01-12 17:39:24 -0800650extern int arch_probe_nr_irqs(void);
Yinghai Lu43a25632008-12-28 16:01:13 -0800651extern int arch_early_irq_init(void);
Yinghai Lu43a25632008-12-28 16:01:13 -0800652
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653#endif