Linux kernel mirror (for testing)
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linux
1/* interrupt.h */
2#ifndef _LINUX_INTERRUPT_H
3#define _LINUX_INTERRUPT_H
4
5#include <linux/kernel.h>
6#include <linux/linkage.h>
7#include <linux/bitops.h>
8#include <linux/preempt.h>
9#include <linux/cpumask.h>
10#include <linux/irqreturn.h>
11#include <linux/hardirq.h>
12#include <linux/sched.h>
13#include <linux/irqflags.h>
14#include <asm/atomic.h>
15#include <asm/ptrace.h>
16#include <asm/system.h>
17
18/*
19 * These correspond to the IORESOURCE_IRQ_* defines in
20 * linux/ioport.h to select the interrupt line behaviour. When
21 * requesting an interrupt without specifying a IRQF_TRIGGER, the
22 * setting should be assumed to be "as already configured", which
23 * may be as per machine or firmware initialisation.
24 */
25#define IRQF_TRIGGER_NONE 0x00000000
26#define IRQF_TRIGGER_RISING 0x00000001
27#define IRQF_TRIGGER_FALLING 0x00000002
28#define IRQF_TRIGGER_HIGH 0x00000004
29#define IRQF_TRIGGER_LOW 0x00000008
30#define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
31 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
32#define IRQF_TRIGGER_PROBE 0x00000010
33
34/*
35 * These flags used only by the kernel as part of the
36 * irq handling routines.
37 *
38 * IRQF_DISABLED - keep irqs disabled when calling the action handler
39 * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
40 * IRQF_SHARED - allow sharing the irq among several devices
41 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
42 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
43 * IRQF_PERCPU - Interrupt is per cpu
44 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
45 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
46 * registered first in an shared interrupt is considered for
47 * performance reasons)
48 */
49#define IRQF_DISABLED 0x00000020
50#define IRQF_SAMPLE_RANDOM 0x00000040
51#define IRQF_SHARED 0x00000080
52#define IRQF_PROBE_SHARED 0x00000100
53#define IRQF_TIMER 0x00000200
54#define IRQF_PERCPU 0x00000400
55#define IRQF_NOBALANCING 0x00000800
56#define IRQF_IRQPOLL 0x00001000
57
58typedef irqreturn_t (*irq_handler_t)(int, void *);
59
60struct irqaction {
61 irq_handler_t handler;
62 unsigned long flags;
63 cpumask_t mask;
64 const char *name;
65 void *dev_id;
66 struct irqaction *next;
67 int irq;
68 struct proc_dir_entry *dir;
69};
70
71extern irqreturn_t no_action(int cpl, void *dev_id);
72extern int __must_check request_irq(unsigned int, irq_handler_t handler,
73 unsigned long, const char *, void *);
74extern void free_irq(unsigned int, void *);
75
76struct device;
77
78extern int __must_check devm_request_irq(struct device *dev, unsigned int irq,
79 irq_handler_t handler, unsigned long irqflags,
80 const char *devname, void *dev_id);
81extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
82
83/*
84 * On lockdep we dont want to enable hardirqs in hardirq
85 * context. Use local_irq_enable_in_hardirq() to annotate
86 * kernel code that has to do this nevertheless (pretty much
87 * the only valid case is for old/broken hardware that is
88 * insanely slow).
89 *
90 * NOTE: in theory this might break fragile code that relies
91 * on hardirq delivery - in practice we dont seem to have such
92 * places left. So the only effect should be slightly increased
93 * irqs-off latencies.
94 */
95#ifdef CONFIG_LOCKDEP
96# define local_irq_enable_in_hardirq() do { } while (0)
97#else
98# define local_irq_enable_in_hardirq() local_irq_enable()
99#endif
100
101extern void disable_irq_nosync(unsigned int irq);
102extern void disable_irq(unsigned int irq);
103extern void enable_irq(unsigned int irq);
104
105#ifdef CONFIG_GENERIC_HARDIRQS
106/*
107 * Special lockdep variants of irq disabling/enabling.
108 * These should be used for locking constructs that
109 * know that a particular irq context which is disabled,
110 * and which is the only irq-context user of a lock,
111 * that it's safe to take the lock in the irq-disabled
112 * section without disabling hardirqs.
113 *
114 * On !CONFIG_LOCKDEP they are equivalent to the normal
115 * irq disable/enable methods.
116 */
117static inline void disable_irq_nosync_lockdep(unsigned int irq)
118{
119 disable_irq_nosync(irq);
120#ifdef CONFIG_LOCKDEP
121 local_irq_disable();
122#endif
123}
124
125static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
126{
127 disable_irq_nosync(irq);
128#ifdef CONFIG_LOCKDEP
129 local_irq_save(*flags);
130#endif
131}
132
133static inline void disable_irq_lockdep(unsigned int irq)
134{
135 disable_irq(irq);
136#ifdef CONFIG_LOCKDEP
137 local_irq_disable();
138#endif
139}
140
141static inline void enable_irq_lockdep(unsigned int irq)
142{
143#ifdef CONFIG_LOCKDEP
144 local_irq_enable();
145#endif
146 enable_irq(irq);
147}
148
149static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
150{
151#ifdef CONFIG_LOCKDEP
152 local_irq_restore(*flags);
153#endif
154 enable_irq(irq);
155}
156
157/* IRQ wakeup (PM) control: */
158extern int set_irq_wake(unsigned int irq, unsigned int on);
159
160static inline int enable_irq_wake(unsigned int irq)
161{
162 return set_irq_wake(irq, 1);
163}
164
165static inline int disable_irq_wake(unsigned int irq)
166{
167 return set_irq_wake(irq, 0);
168}
169
170#else /* !CONFIG_GENERIC_HARDIRQS */
171/*
172 * NOTE: non-genirq architectures, if they want to support the lock
173 * validator need to define the methods below in their asm/irq.h
174 * files, under an #ifdef CONFIG_LOCKDEP section.
175 */
176#ifndef CONFIG_LOCKDEP
177# define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq)
178# define disable_irq_nosync_lockdep_irqsave(irq, flags) \
179 disable_irq_nosync(irq)
180# define disable_irq_lockdep(irq) disable_irq(irq)
181# define enable_irq_lockdep(irq) enable_irq(irq)
182# define enable_irq_lockdep_irqrestore(irq, flags) \
183 enable_irq(irq)
184# endif
185
186static inline int enable_irq_wake(unsigned int irq)
187{
188 return 0;
189}
190
191static inline int disable_irq_wake(unsigned int irq)
192{
193 return 0;
194}
195#endif /* CONFIG_GENERIC_HARDIRQS */
196
197#ifndef __ARCH_SET_SOFTIRQ_PENDING
198#define set_softirq_pending(x) (local_softirq_pending() = (x))
199#define or_softirq_pending(x) (local_softirq_pending() |= (x))
200#endif
201
202/*
203 * Temporary defines for UP kernels, until all code gets fixed.
204 */
205#ifndef CONFIG_SMP
206static inline void __deprecated cli(void)
207{
208 local_irq_disable();
209}
210static inline void __deprecated sti(void)
211{
212 local_irq_enable();
213}
214static inline void __deprecated save_flags(unsigned long *x)
215{
216 local_save_flags(*x);
217}
218#define save_flags(x) save_flags(&x)
219static inline void __deprecated restore_flags(unsigned long x)
220{
221 local_irq_restore(x);
222}
223
224static inline void __deprecated save_and_cli(unsigned long *x)
225{
226 local_irq_save(*x);
227}
228#define save_and_cli(x) save_and_cli(&x)
229#endif /* CONFIG_SMP */
230
231/* Some architectures might implement lazy enabling/disabling of
232 * interrupts. In some cases, such as stop_machine, we might want
233 * to ensure that after a local_irq_disable(), interrupts have
234 * really been disabled in hardware. Such architectures need to
235 * implement the following hook.
236 */
237#ifndef hard_irq_disable
238#define hard_irq_disable() do { } while(0)
239#endif
240
241/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
242 frequency threaded job scheduling. For almost all the purposes
243 tasklets are more than enough. F.e. all serial device BHs et
244 al. should be converted to tasklets, not to softirqs.
245 */
246
247enum
248{
249 HI_SOFTIRQ=0,
250 TIMER_SOFTIRQ,
251 NET_TX_SOFTIRQ,
252 NET_RX_SOFTIRQ,
253 BLOCK_SOFTIRQ,
254 TASKLET_SOFTIRQ,
255 SCHED_SOFTIRQ,
256#ifdef CONFIG_HIGH_RES_TIMERS
257 HRTIMER_SOFTIRQ,
258#endif
259 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
260};
261
262/* softirq mask and active fields moved to irq_cpustat_t in
263 * asm/hardirq.h to get better cache usage. KAO
264 */
265
266struct softirq_action
267{
268 void (*action)(struct softirq_action *);
269 void *data;
270};
271
272asmlinkage void do_softirq(void);
273extern void open_softirq(int nr, void (*action)(struct softirq_action*), void *data);
274extern void softirq_init(void);
275#define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)
276extern void raise_softirq_irqoff(unsigned int nr);
277extern void raise_softirq(unsigned int nr);
278
279
280/* Tasklets --- multithreaded analogue of BHs.
281
282 Main feature differing them of generic softirqs: tasklet
283 is running only on one CPU simultaneously.
284
285 Main feature differing them of BHs: different tasklets
286 may be run simultaneously on different CPUs.
287
288 Properties:
289 * If tasklet_schedule() is called, then tasklet is guaranteed
290 to be executed on some cpu at least once after this.
291 * If the tasklet is already scheduled, but its excecution is still not
292 started, it will be executed only once.
293 * If this tasklet is already running on another CPU (or schedule is called
294 from tasklet itself), it is rescheduled for later.
295 * Tasklet is strictly serialized wrt itself, but not
296 wrt another tasklets. If client needs some intertask synchronization,
297 he makes it with spinlocks.
298 */
299
300struct tasklet_struct
301{
302 struct tasklet_struct *next;
303 unsigned long state;
304 atomic_t count;
305 void (*func)(unsigned long);
306 unsigned long data;
307};
308
309#define DECLARE_TASKLET(name, func, data) \
310struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
311
312#define DECLARE_TASKLET_DISABLED(name, func, data) \
313struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
314
315
316enum
317{
318 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
319 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
320};
321
322#ifdef CONFIG_SMP
323static inline int tasklet_trylock(struct tasklet_struct *t)
324{
325 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
326}
327
328static inline void tasklet_unlock(struct tasklet_struct *t)
329{
330 smp_mb__before_clear_bit();
331 clear_bit(TASKLET_STATE_RUN, &(t)->state);
332}
333
334static inline void tasklet_unlock_wait(struct tasklet_struct *t)
335{
336 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
337}
338#else
339#define tasklet_trylock(t) 1
340#define tasklet_unlock_wait(t) do { } while (0)
341#define tasklet_unlock(t) do { } while (0)
342#endif
343
344extern void __tasklet_schedule(struct tasklet_struct *t);
345
346static inline void tasklet_schedule(struct tasklet_struct *t)
347{
348 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
349 __tasklet_schedule(t);
350}
351
352extern void __tasklet_hi_schedule(struct tasklet_struct *t);
353
354static inline void tasklet_hi_schedule(struct tasklet_struct *t)
355{
356 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
357 __tasklet_hi_schedule(t);
358}
359
360
361static inline void tasklet_disable_nosync(struct tasklet_struct *t)
362{
363 atomic_inc(&t->count);
364 smp_mb__after_atomic_inc();
365}
366
367static inline void tasklet_disable(struct tasklet_struct *t)
368{
369 tasklet_disable_nosync(t);
370 tasklet_unlock_wait(t);
371 smp_mb();
372}
373
374static inline void tasklet_enable(struct tasklet_struct *t)
375{
376 smp_mb__before_atomic_dec();
377 atomic_dec(&t->count);
378}
379
380static inline void tasklet_hi_enable(struct tasklet_struct *t)
381{
382 smp_mb__before_atomic_dec();
383 atomic_dec(&t->count);
384}
385
386extern void tasklet_kill(struct tasklet_struct *t);
387extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
388extern void tasklet_init(struct tasklet_struct *t,
389 void (*func)(unsigned long), unsigned long data);
390
391/*
392 * Autoprobing for irqs:
393 *
394 * probe_irq_on() and probe_irq_off() provide robust primitives
395 * for accurate IRQ probing during kernel initialization. They are
396 * reasonably simple to use, are not "fooled" by spurious interrupts,
397 * and, unlike other attempts at IRQ probing, they do not get hung on
398 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
399 *
400 * For reasonably foolproof probing, use them as follows:
401 *
402 * 1. clear and/or mask the device's internal interrupt.
403 * 2. sti();
404 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
405 * 4. enable the device and cause it to trigger an interrupt.
406 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
407 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
408 * 7. service the device to clear its pending interrupt.
409 * 8. loop again if paranoia is required.
410 *
411 * probe_irq_on() returns a mask of allocated irq's.
412 *
413 * probe_irq_off() takes the mask as a parameter,
414 * and returns the irq number which occurred,
415 * or zero if none occurred, or a negative irq number
416 * if more than one irq occurred.
417 */
418
419#if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
420static inline unsigned long probe_irq_on(void)
421{
422 return 0;
423}
424static inline int probe_irq_off(unsigned long val)
425{
426 return 0;
427}
428static inline unsigned int probe_irq_mask(unsigned long val)
429{
430 return 0;
431}
432#else
433extern unsigned long probe_irq_on(void); /* returns 0 on failure */
434extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
435extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
436#endif
437
438#ifdef CONFIG_PROC_FS
439/* Initialize /proc/irq/ */
440extern void init_irq_proc(void);
441#else
442static inline void init_irq_proc(void)
443{
444}
445#endif
446
447int show_interrupts(struct seq_file *p, void *v);
448
449#endif