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