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 <linux/bottom_half.h>
15#include <linux/device.h>
16#include <asm/atomic.h>
17#include <asm/ptrace.h>
18#include <asm/system.h>
19
20/*
21 * These correspond to the IORESOURCE_IRQ_* defines in
22 * linux/ioport.h to select the interrupt line behaviour. When
23 * requesting an interrupt without specifying a IRQF_TRIGGER, the
24 * setting should be assumed to be "as already configured", which
25 * may be as per machine or firmware initialisation.
26 */
27#define IRQF_TRIGGER_NONE 0x00000000
28#define IRQF_TRIGGER_RISING 0x00000001
29#define IRQF_TRIGGER_FALLING 0x00000002
30#define IRQF_TRIGGER_HIGH 0x00000004
31#define IRQF_TRIGGER_LOW 0x00000008
32#define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
33 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
34#define IRQF_TRIGGER_PROBE 0x00000010
35
36/*
37 * These flags used only by the kernel as part of the
38 * irq handling routines.
39 *
40 * IRQF_DISABLED - keep irqs disabled when calling the action handler
41 * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
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 */
48#define IRQF_DISABLED 0x00000020
49#define IRQF_SAMPLE_RANDOM 0x00000040
50#define IRQF_SHARED 0x00000080
51#define IRQF_PROBE_SHARED 0x00000100
52#define IRQF_TIMER 0x00000200
53#define IRQF_PERCPU 0x00000400
54#define IRQF_NOBALANCING 0x00000800
55
56/*
57 * Migration helpers. Scheduled for removal in 1/2007
58 * Do not use for new code !
59 */
60#define SA_INTERRUPT IRQF_DISABLED
61#define SA_SAMPLE_RANDOM IRQF_SAMPLE_RANDOM
62#define SA_SHIRQ IRQF_SHARED
63#define SA_PROBEIRQ IRQF_PROBE_SHARED
64#define SA_PERCPU IRQF_PERCPU
65
66#define SA_TRIGGER_LOW IRQF_TRIGGER_LOW
67#define SA_TRIGGER_HIGH IRQF_TRIGGER_HIGH
68#define SA_TRIGGER_FALLING IRQF_TRIGGER_FALLING
69#define SA_TRIGGER_RISING IRQF_TRIGGER_RISING
70#define SA_TRIGGER_MASK IRQF_TRIGGER_MASK
71
72typedef irqreturn_t (*irq_handler_t)(int, void *);
73
74struct irqaction {
75 irq_handler_t handler;
76 unsigned long flags;
77 cpumask_t mask;
78 const char *name;
79 void *dev_id;
80 struct irqaction *next;
81 int irq;
82 struct proc_dir_entry *dir;
83};
84
85extern irqreturn_t no_action(int cpl, void *dev_id);
86extern int request_irq(unsigned int, irq_handler_t handler,
87 unsigned long, const char *, void *);
88extern void free_irq(unsigned int, void *);
89
90extern int devm_request_irq(struct device *dev, unsigned int irq,
91 irq_handler_t handler, unsigned long irqflags,
92 const char *devname, void *dev_id);
93extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
94
95/*
96 * On lockdep we dont want to enable hardirqs in hardirq
97 * context. Use local_irq_enable_in_hardirq() to annotate
98 * kernel code that has to do this nevertheless (pretty much
99 * the only valid case is for old/broken hardware that is
100 * insanely slow).
101 *
102 * NOTE: in theory this might break fragile code that relies
103 * on hardirq delivery - in practice we dont seem to have such
104 * places left. So the only effect should be slightly increased
105 * irqs-off latencies.
106 */
107#ifdef CONFIG_LOCKDEP
108# define local_irq_enable_in_hardirq() do { } while (0)
109#else
110# define local_irq_enable_in_hardirq() local_irq_enable()
111#endif
112
113#ifdef CONFIG_GENERIC_HARDIRQS
114extern void disable_irq_nosync(unsigned int irq);
115extern void disable_irq(unsigned int irq);
116extern void enable_irq(unsigned int irq);
117
118/*
119 * Special lockdep variants of irq disabling/enabling.
120 * These should be used for locking constructs that
121 * know that a particular irq context which is disabled,
122 * and which is the only irq-context user of a lock,
123 * that it's safe to take the lock in the irq-disabled
124 * section without disabling hardirqs.
125 *
126 * On !CONFIG_LOCKDEP they are equivalent to the normal
127 * irq disable/enable methods.
128 */
129static inline void disable_irq_nosync_lockdep(unsigned int irq)
130{
131 disable_irq_nosync(irq);
132#ifdef CONFIG_LOCKDEP
133 local_irq_disable();
134#endif
135}
136
137static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
138{
139 disable_irq_nosync(irq);
140#ifdef CONFIG_LOCKDEP
141 local_irq_save(*flags);
142#endif
143}
144
145static inline void disable_irq_lockdep(unsigned int irq)
146{
147 disable_irq(irq);
148#ifdef CONFIG_LOCKDEP
149 local_irq_disable();
150#endif
151}
152
153static inline void enable_irq_lockdep(unsigned int irq)
154{
155#ifdef CONFIG_LOCKDEP
156 local_irq_enable();
157#endif
158 enable_irq(irq);
159}
160
161static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
162{
163#ifdef CONFIG_LOCKDEP
164 local_irq_restore(*flags);
165#endif
166 enable_irq(irq);
167}
168
169/* IRQ wakeup (PM) control: */
170extern int set_irq_wake(unsigned int irq, unsigned int on);
171
172static inline int enable_irq_wake(unsigned int irq)
173{
174 return set_irq_wake(irq, 1);
175}
176
177static inline int disable_irq_wake(unsigned int irq)
178{
179 return set_irq_wake(irq, 0);
180}
181
182#else /* !CONFIG_GENERIC_HARDIRQS */
183/*
184 * NOTE: non-genirq architectures, if they want to support the lock
185 * validator need to define the methods below in their asm/irq.h
186 * files, under an #ifdef CONFIG_LOCKDEP section.
187 */
188# ifndef CONFIG_LOCKDEP
189# define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq)
190# define disable_irq_lockdep(irq) disable_irq(irq)
191# define enable_irq_lockdep(irq) enable_irq(irq)
192# endif
193
194#endif /* CONFIG_GENERIC_HARDIRQS */
195
196#ifndef __ARCH_SET_SOFTIRQ_PENDING
197#define set_softirq_pending(x) (local_softirq_pending() = (x))
198#define or_softirq_pending(x) (local_softirq_pending() |= (x))
199#endif
200
201/*
202 * Temporary defines for UP kernels, until all code gets fixed.
203 */
204#ifndef CONFIG_SMP
205static inline void __deprecated cli(void)
206{
207 local_irq_disable();
208}
209static inline void __deprecated sti(void)
210{
211 local_irq_enable();
212}
213static inline void __deprecated save_flags(unsigned long *x)
214{
215 local_save_flags(*x);
216}
217#define save_flags(x) save_flags(&x)
218static inline void __deprecated restore_flags(unsigned long x)
219{
220 local_irq_restore(x);
221}
222
223static inline void __deprecated save_and_cli(unsigned long *x)
224{
225 local_irq_save(*x);
226}
227#define save_and_cli(x) save_and_cli(&x)
228#endif /* CONFIG_SMP */
229
230/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
231 frequency threaded job scheduling. For almost all the purposes
232 tasklets are more than enough. F.e. all serial device BHs et
233 al. should be converted to tasklets, not to softirqs.
234 */
235
236enum
237{
238 HI_SOFTIRQ=0,
239 TIMER_SOFTIRQ,
240 NET_TX_SOFTIRQ,
241 NET_RX_SOFTIRQ,
242 BLOCK_SOFTIRQ,
243 TASKLET_SOFTIRQ,
244 SCHED_SOFTIRQ,
245#ifdef CONFIG_HIGH_RES_TIMERS
246 HRTIMER_SOFTIRQ,
247#endif
248};
249
250/* softirq mask and active fields moved to irq_cpustat_t in
251 * asm/hardirq.h to get better cache usage. KAO
252 */
253
254struct softirq_action
255{
256 void (*action)(struct softirq_action *);
257 void *data;
258};
259
260asmlinkage void do_softirq(void);
261extern void open_softirq(int nr, void (*action)(struct softirq_action*), void *data);
262extern void softirq_init(void);
263#define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)
264extern void FASTCALL(raise_softirq_irqoff(unsigned int nr));
265extern void FASTCALL(raise_softirq(unsigned int nr));
266
267
268/* Tasklets --- multithreaded analogue of BHs.
269
270 Main feature differing them of generic softirqs: tasklet
271 is running only on one CPU simultaneously.
272
273 Main feature differing them of BHs: different tasklets
274 may be run simultaneously on different CPUs.
275
276 Properties:
277 * If tasklet_schedule() is called, then tasklet is guaranteed
278 to be executed on some cpu at least once after this.
279 * If the tasklet is already scheduled, but its excecution is still not
280 started, it will be executed only once.
281 * If this tasklet is already running on another CPU (or schedule is called
282 from tasklet itself), it is rescheduled for later.
283 * Tasklet is strictly serialized wrt itself, but not
284 wrt another tasklets. If client needs some intertask synchronization,
285 he makes it with spinlocks.
286 */
287
288struct tasklet_struct
289{
290 struct tasklet_struct *next;
291 unsigned long state;
292 atomic_t count;
293 void (*func)(unsigned long);
294 unsigned long data;
295};
296
297#define DECLARE_TASKLET(name, func, data) \
298struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
299
300#define DECLARE_TASKLET_DISABLED(name, func, data) \
301struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
302
303
304enum
305{
306 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
307 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
308};
309
310#ifdef CONFIG_SMP
311static inline int tasklet_trylock(struct tasklet_struct *t)
312{
313 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
314}
315
316static inline void tasklet_unlock(struct tasklet_struct *t)
317{
318 smp_mb__before_clear_bit();
319 clear_bit(TASKLET_STATE_RUN, &(t)->state);
320}
321
322static inline void tasklet_unlock_wait(struct tasklet_struct *t)
323{
324 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
325}
326#else
327#define tasklet_trylock(t) 1
328#define tasklet_unlock_wait(t) do { } while (0)
329#define tasklet_unlock(t) do { } while (0)
330#endif
331
332extern void FASTCALL(__tasklet_schedule(struct tasklet_struct *t));
333
334static inline void tasklet_schedule(struct tasklet_struct *t)
335{
336 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
337 __tasklet_schedule(t);
338}
339
340extern void FASTCALL(__tasklet_hi_schedule(struct tasklet_struct *t));
341
342static inline void tasklet_hi_schedule(struct tasklet_struct *t)
343{
344 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
345 __tasklet_hi_schedule(t);
346}
347
348
349static inline void tasklet_disable_nosync(struct tasklet_struct *t)
350{
351 atomic_inc(&t->count);
352 smp_mb__after_atomic_inc();
353}
354
355static inline void tasklet_disable(struct tasklet_struct *t)
356{
357 tasklet_disable_nosync(t);
358 tasklet_unlock_wait(t);
359 smp_mb();
360}
361
362static inline void tasklet_enable(struct tasklet_struct *t)
363{
364 smp_mb__before_atomic_dec();
365 atomic_dec(&t->count);
366}
367
368static inline void tasklet_hi_enable(struct tasklet_struct *t)
369{
370 smp_mb__before_atomic_dec();
371 atomic_dec(&t->count);
372}
373
374extern void tasklet_kill(struct tasklet_struct *t);
375extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
376extern void tasklet_init(struct tasklet_struct *t,
377 void (*func)(unsigned long), unsigned long data);
378
379/*
380 * Autoprobing for irqs:
381 *
382 * probe_irq_on() and probe_irq_off() provide robust primitives
383 * for accurate IRQ probing during kernel initialization. They are
384 * reasonably simple to use, are not "fooled" by spurious interrupts,
385 * and, unlike other attempts at IRQ probing, they do not get hung on
386 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
387 *
388 * For reasonably foolproof probing, use them as follows:
389 *
390 * 1. clear and/or mask the device's internal interrupt.
391 * 2. sti();
392 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
393 * 4. enable the device and cause it to trigger an interrupt.
394 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
395 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
396 * 7. service the device to clear its pending interrupt.
397 * 8. loop again if paranoia is required.
398 *
399 * probe_irq_on() returns a mask of allocated irq's.
400 *
401 * probe_irq_off() takes the mask as a parameter,
402 * and returns the irq number which occurred,
403 * or zero if none occurred, or a negative irq number
404 * if more than one irq occurred.
405 */
406
407#if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
408static inline unsigned long probe_irq_on(void)
409{
410 return 0;
411}
412static inline int probe_irq_off(unsigned long val)
413{
414 return 0;
415}
416static inline unsigned int probe_irq_mask(unsigned long val)
417{
418 return 0;
419}
420#else
421extern unsigned long probe_irq_on(void); /* returns 0 on failure */
422extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
423extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
424#endif
425
426#ifdef CONFIG_PROC_FS
427/* Initialize /proc/irq/ */
428extern void init_irq_proc(void);
429#else
430static inline void init_irq_proc(void)
431{
432}
433#endif
434
435#endif