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/irqnr.h>
12#include <linux/hardirq.h>
13#include <linux/sched.h>
14#include <linux/irqflags.h>
15#include <linux/smp.h>
16#include <linux/percpu.h>
17#include <asm/atomic.h>
18#include <asm/ptrace.h>
19#include <asm/system.h>
20
21/*
22 * These correspond to the IORESOURCE_IRQ_* defines in
23 * linux/ioport.h to select the interrupt line behaviour. When
24 * requesting an interrupt without specifying a IRQF_TRIGGER, the
25 * setting should be assumed to be "as already configured", which
26 * may be as per machine or firmware initialisation.
27 */
28#define IRQF_TRIGGER_NONE 0x00000000
29#define IRQF_TRIGGER_RISING 0x00000001
30#define IRQF_TRIGGER_FALLING 0x00000002
31#define IRQF_TRIGGER_HIGH 0x00000004
32#define IRQF_TRIGGER_LOW 0x00000008
33#define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
34 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
35#define IRQF_TRIGGER_PROBE 0x00000010
36
37/*
38 * These flags used only by the kernel as part of the
39 * irq handling routines.
40 *
41 * IRQF_DISABLED - keep irqs disabled when calling the action handler
42 * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
43 * IRQF_SHARED - allow sharing the irq among several devices
44 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
45 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
46 * IRQF_PERCPU - Interrupt is per cpu
47 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
48 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
49 * registered first in an shared interrupt is considered for
50 * performance reasons)
51 */
52#define IRQF_DISABLED 0x00000020
53#define IRQF_SAMPLE_RANDOM 0x00000040
54#define IRQF_SHARED 0x00000080
55#define IRQF_PROBE_SHARED 0x00000100
56#define IRQF_TIMER 0x00000200
57#define IRQF_PERCPU 0x00000400
58#define IRQF_NOBALANCING 0x00000800
59#define IRQF_IRQPOLL 0x00001000
60
61typedef irqreturn_t (*irq_handler_t)(int, void *);
62
63struct irqaction {
64 irq_handler_t handler;
65 unsigned long flags;
66 cpumask_t mask;
67 const char *name;
68 void *dev_id;
69 struct irqaction *next;
70 int irq;
71 struct proc_dir_entry *dir;
72};
73
74extern irqreturn_t no_action(int cpl, void *dev_id);
75extern int __must_check request_irq(unsigned int, irq_handler_t handler,
76 unsigned long, const char *, void *);
77extern void free_irq(unsigned int, void *);
78
79struct device;
80
81extern int __must_check devm_request_irq(struct device *dev, unsigned int irq,
82 irq_handler_t handler, unsigned long irqflags,
83 const char *devname, void *dev_id);
84extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
85
86/*
87 * On lockdep we dont want to enable hardirqs in hardirq
88 * context. Use local_irq_enable_in_hardirq() to annotate
89 * kernel code that has to do this nevertheless (pretty much
90 * the only valid case is for old/broken hardware that is
91 * insanely slow).
92 *
93 * NOTE: in theory this might break fragile code that relies
94 * on hardirq delivery - in practice we dont seem to have such
95 * places left. So the only effect should be slightly increased
96 * irqs-off latencies.
97 */
98#ifdef CONFIG_LOCKDEP
99# define local_irq_enable_in_hardirq() do { } while (0)
100#else
101# define local_irq_enable_in_hardirq() local_irq_enable()
102#endif
103
104extern void disable_irq_nosync(unsigned int irq);
105extern void disable_irq(unsigned int irq);
106extern void enable_irq(unsigned int irq);
107
108#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
109
110extern cpumask_t irq_default_affinity;
111
112extern int irq_set_affinity(unsigned int irq, cpumask_t cpumask);
113extern int irq_can_set_affinity(unsigned int irq);
114extern int irq_select_affinity(unsigned int irq);
115
116#else /* CONFIG_SMP */
117
118static inline int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
119{
120 return -EINVAL;
121}
122
123static inline int irq_can_set_affinity(unsigned int irq)
124{
125 return 0;
126}
127
128static inline int irq_select_affinity(unsigned int irq) { return 0; }
129
130#endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
131
132#ifdef CONFIG_GENERIC_HARDIRQS
133/*
134 * Special lockdep variants of irq disabling/enabling.
135 * These should be used for locking constructs that
136 * know that a particular irq context which is disabled,
137 * and which is the only irq-context user of a lock,
138 * that it's safe to take the lock in the irq-disabled
139 * section without disabling hardirqs.
140 *
141 * On !CONFIG_LOCKDEP they are equivalent to the normal
142 * irq disable/enable methods.
143 */
144static inline void disable_irq_nosync_lockdep(unsigned int irq)
145{
146 disable_irq_nosync(irq);
147#ifdef CONFIG_LOCKDEP
148 local_irq_disable();
149#endif
150}
151
152static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
153{
154 disable_irq_nosync(irq);
155#ifdef CONFIG_LOCKDEP
156 local_irq_save(*flags);
157#endif
158}
159
160static inline void disable_irq_lockdep(unsigned int irq)
161{
162 disable_irq(irq);
163#ifdef CONFIG_LOCKDEP
164 local_irq_disable();
165#endif
166}
167
168static inline void enable_irq_lockdep(unsigned int irq)
169{
170#ifdef CONFIG_LOCKDEP
171 local_irq_enable();
172#endif
173 enable_irq(irq);
174}
175
176static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
177{
178#ifdef CONFIG_LOCKDEP
179 local_irq_restore(*flags);
180#endif
181 enable_irq(irq);
182}
183
184/* IRQ wakeup (PM) control: */
185extern int set_irq_wake(unsigned int irq, unsigned int on);
186
187static inline int enable_irq_wake(unsigned int irq)
188{
189 return set_irq_wake(irq, 1);
190}
191
192static inline int disable_irq_wake(unsigned int irq)
193{
194 return set_irq_wake(irq, 0);
195}
196
197#else /* !CONFIG_GENERIC_HARDIRQS */
198/*
199 * NOTE: non-genirq architectures, if they want to support the lock
200 * validator need to define the methods below in their asm/irq.h
201 * files, under an #ifdef CONFIG_LOCKDEP section.
202 */
203#ifndef CONFIG_LOCKDEP
204# define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq)
205# define disable_irq_nosync_lockdep_irqsave(irq, flags) \
206 disable_irq_nosync(irq)
207# define disable_irq_lockdep(irq) disable_irq(irq)
208# define enable_irq_lockdep(irq) enable_irq(irq)
209# define enable_irq_lockdep_irqrestore(irq, flags) \
210 enable_irq(irq)
211# endif
212
213static inline int enable_irq_wake(unsigned int irq)
214{
215 return 0;
216}
217
218static inline int disable_irq_wake(unsigned int irq)
219{
220 return 0;
221}
222#endif /* CONFIG_GENERIC_HARDIRQS */
223
224#ifndef __ARCH_SET_SOFTIRQ_PENDING
225#define set_softirq_pending(x) (local_softirq_pending() = (x))
226#define or_softirq_pending(x) (local_softirq_pending() |= (x))
227#endif
228
229/* Some architectures might implement lazy enabling/disabling of
230 * interrupts. In some cases, such as stop_machine, we might want
231 * to ensure that after a local_irq_disable(), interrupts have
232 * really been disabled in hardware. Such architectures need to
233 * implement the following hook.
234 */
235#ifndef hard_irq_disable
236#define hard_irq_disable() do { } while(0)
237#endif
238
239/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
240 frequency threaded job scheduling. For almost all the purposes
241 tasklets are more than enough. F.e. all serial device BHs et
242 al. should be converted to tasklets, not to softirqs.
243 */
244
245enum
246{
247 HI_SOFTIRQ=0,
248 TIMER_SOFTIRQ,
249 NET_TX_SOFTIRQ,
250 NET_RX_SOFTIRQ,
251 BLOCK_SOFTIRQ,
252 TASKLET_SOFTIRQ,
253 SCHED_SOFTIRQ,
254#ifdef CONFIG_HIGH_RES_TIMERS
255 HRTIMER_SOFTIRQ,
256#endif
257 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
258
259 NR_SOFTIRQS
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};
270
271asmlinkage void do_softirq(void);
272asmlinkage void __do_softirq(void);
273extern void open_softirq(int nr, void (*action)(struct softirq_action *));
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/* This is the worklist that queues up per-cpu softirq work.
280 *
281 * send_remote_sendirq() adds work to these lists, and
282 * the softirq handler itself dequeues from them. The queues
283 * are protected by disabling local cpu interrupts and they must
284 * only be accessed by the local cpu that they are for.
285 */
286DECLARE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list);
287
288/* Try to send a softirq to a remote cpu. If this cannot be done, the
289 * work will be queued to the local cpu.
290 */
291extern void send_remote_softirq(struct call_single_data *cp, int cpu, int softirq);
292
293/* Like send_remote_softirq(), but the caller must disable local cpu interrupts
294 * and compute the current cpu, passed in as 'this_cpu'.
295 */
296extern void __send_remote_softirq(struct call_single_data *cp, int cpu,
297 int this_cpu, int softirq);
298
299/* Tasklets --- multithreaded analogue of BHs.
300
301 Main feature differing them of generic softirqs: tasklet
302 is running only on one CPU simultaneously.
303
304 Main feature differing them of BHs: different tasklets
305 may be run simultaneously on different CPUs.
306
307 Properties:
308 * If tasklet_schedule() is called, then tasklet is guaranteed
309 to be executed on some cpu at least once after this.
310 * If the tasklet is already scheduled, but its excecution is still not
311 started, it will be executed only once.
312 * If this tasklet is already running on another CPU (or schedule is called
313 from tasklet itself), it is rescheduled for later.
314 * Tasklet is strictly serialized wrt itself, but not
315 wrt another tasklets. If client needs some intertask synchronization,
316 he makes it with spinlocks.
317 */
318
319struct tasklet_struct
320{
321 struct tasklet_struct *next;
322 unsigned long state;
323 atomic_t count;
324 void (*func)(unsigned long);
325 unsigned long data;
326};
327
328#define DECLARE_TASKLET(name, func, data) \
329struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
330
331#define DECLARE_TASKLET_DISABLED(name, func, data) \
332struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
333
334
335enum
336{
337 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
338 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
339};
340
341#ifdef CONFIG_SMP
342static inline int tasklet_trylock(struct tasklet_struct *t)
343{
344 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
345}
346
347static inline void tasklet_unlock(struct tasklet_struct *t)
348{
349 smp_mb__before_clear_bit();
350 clear_bit(TASKLET_STATE_RUN, &(t)->state);
351}
352
353static inline void tasklet_unlock_wait(struct tasklet_struct *t)
354{
355 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
356}
357#else
358#define tasklet_trylock(t) 1
359#define tasklet_unlock_wait(t) do { } while (0)
360#define tasklet_unlock(t) do { } while (0)
361#endif
362
363extern void __tasklet_schedule(struct tasklet_struct *t);
364
365static inline void tasklet_schedule(struct tasklet_struct *t)
366{
367 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
368 __tasklet_schedule(t);
369}
370
371extern void __tasklet_hi_schedule(struct tasklet_struct *t);
372
373static inline void tasklet_hi_schedule(struct tasklet_struct *t)
374{
375 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
376 __tasklet_hi_schedule(t);
377}
378
379
380static inline void tasklet_disable_nosync(struct tasklet_struct *t)
381{
382 atomic_inc(&t->count);
383 smp_mb__after_atomic_inc();
384}
385
386static inline void tasklet_disable(struct tasklet_struct *t)
387{
388 tasklet_disable_nosync(t);
389 tasklet_unlock_wait(t);
390 smp_mb();
391}
392
393static inline void tasklet_enable(struct tasklet_struct *t)
394{
395 smp_mb__before_atomic_dec();
396 atomic_dec(&t->count);
397}
398
399static inline void tasklet_hi_enable(struct tasklet_struct *t)
400{
401 smp_mb__before_atomic_dec();
402 atomic_dec(&t->count);
403}
404
405extern void tasklet_kill(struct tasklet_struct *t);
406extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
407extern void tasklet_init(struct tasklet_struct *t,
408 void (*func)(unsigned long), unsigned long data);
409
410/*
411 * Autoprobing for irqs:
412 *
413 * probe_irq_on() and probe_irq_off() provide robust primitives
414 * for accurate IRQ probing during kernel initialization. They are
415 * reasonably simple to use, are not "fooled" by spurious interrupts,
416 * and, unlike other attempts at IRQ probing, they do not get hung on
417 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
418 *
419 * For reasonably foolproof probing, use them as follows:
420 *
421 * 1. clear and/or mask the device's internal interrupt.
422 * 2. sti();
423 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
424 * 4. enable the device and cause it to trigger an interrupt.
425 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
426 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
427 * 7. service the device to clear its pending interrupt.
428 * 8. loop again if paranoia is required.
429 *
430 * probe_irq_on() returns a mask of allocated irq's.
431 *
432 * probe_irq_off() takes the mask as a parameter,
433 * and returns the irq number which occurred,
434 * or zero if none occurred, or a negative irq number
435 * if more than one irq occurred.
436 */
437
438#if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
439static inline unsigned long probe_irq_on(void)
440{
441 return 0;
442}
443static inline int probe_irq_off(unsigned long val)
444{
445 return 0;
446}
447static inline unsigned int probe_irq_mask(unsigned long val)
448{
449 return 0;
450}
451#else
452extern unsigned long probe_irq_on(void); /* returns 0 on failure */
453extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
454extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
455#endif
456
457#ifdef CONFIG_PROC_FS
458/* Initialize /proc/irq/ */
459extern void init_irq_proc(void);
460#else
461static inline void init_irq_proc(void)
462{
463}
464#endif
465
466int show_interrupts(struct seq_file *p, void *v);
467
468#endif