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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
4 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
5 *
6 * This file contains the interrupt descriptor management code. Detailed
7 * information is available in Documentation/core-api/genericirq.rst
8 *
9 */
10#include <linux/irq.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/interrupt.h>
14#include <linux/kernel_stat.h>
15#include <linux/radix-tree.h>
16#include <linux/bitmap.h>
17#include <linux/irqdomain.h>
18#include <linux/sysfs.h>
19
20#include "internals.h"
21
22/*
23 * lockdep: we want to handle all irq_desc locks as a single lock-class:
24 */
25static struct lock_class_key irq_desc_lock_class;
26
27#if defined(CONFIG_SMP)
28static int __init irq_affinity_setup(char *str)
29{
30 alloc_bootmem_cpumask_var(&irq_default_affinity);
31 cpulist_parse(str, irq_default_affinity);
32 /*
33 * Set at least the boot cpu. We don't want to end up with
34 * bugreports caused by random commandline masks
35 */
36 cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
37 return 1;
38}
39__setup("irqaffinity=", irq_affinity_setup);
40
41static void __init init_irq_default_affinity(void)
42{
43 if (!cpumask_available(irq_default_affinity))
44 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
45 if (cpumask_empty(irq_default_affinity))
46 cpumask_setall(irq_default_affinity);
47}
48#else
49static void __init init_irq_default_affinity(void)
50{
51}
52#endif
53
54#ifdef CONFIG_SMP
55static int alloc_masks(struct irq_desc *desc, int node)
56{
57 if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
58 GFP_KERNEL, node))
59 return -ENOMEM;
60
61#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
62 if (!zalloc_cpumask_var_node(&desc->irq_common_data.effective_affinity,
63 GFP_KERNEL, node)) {
64 free_cpumask_var(desc->irq_common_data.affinity);
65 return -ENOMEM;
66 }
67#endif
68
69#ifdef CONFIG_GENERIC_PENDING_IRQ
70 if (!zalloc_cpumask_var_node(&desc->pending_mask, GFP_KERNEL, node)) {
71#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
72 free_cpumask_var(desc->irq_common_data.effective_affinity);
73#endif
74 free_cpumask_var(desc->irq_common_data.affinity);
75 return -ENOMEM;
76 }
77#endif
78 return 0;
79}
80
81static void desc_smp_init(struct irq_desc *desc, int node,
82 const struct cpumask *affinity)
83{
84 if (!affinity)
85 affinity = irq_default_affinity;
86 cpumask_copy(desc->irq_common_data.affinity, affinity);
87
88#ifdef CONFIG_GENERIC_PENDING_IRQ
89 cpumask_clear(desc->pending_mask);
90#endif
91#ifdef CONFIG_NUMA
92 desc->irq_common_data.node = node;
93#endif
94}
95
96#else
97static inline int
98alloc_masks(struct irq_desc *desc, int node) { return 0; }
99static inline void
100desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
101#endif
102
103static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
104 const struct cpumask *affinity, struct module *owner)
105{
106 int cpu;
107
108 desc->irq_common_data.handler_data = NULL;
109 desc->irq_common_data.msi_desc = NULL;
110
111 desc->irq_data.common = &desc->irq_common_data;
112 desc->irq_data.irq = irq;
113 desc->irq_data.chip = &no_irq_chip;
114 desc->irq_data.chip_data = NULL;
115 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
116 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
117 irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
118 desc->handle_irq = handle_bad_irq;
119 desc->depth = 1;
120 desc->irq_count = 0;
121 desc->irqs_unhandled = 0;
122 desc->tot_count = 0;
123 desc->name = NULL;
124 desc->owner = owner;
125 for_each_possible_cpu(cpu)
126 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
127 desc_smp_init(desc, node, affinity);
128}
129
130int nr_irqs = NR_IRQS;
131EXPORT_SYMBOL_GPL(nr_irqs);
132
133static DEFINE_MUTEX(sparse_irq_lock);
134static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
135
136#ifdef CONFIG_SPARSE_IRQ
137
138static void irq_kobj_release(struct kobject *kobj);
139
140#ifdef CONFIG_SYSFS
141static struct kobject *irq_kobj_base;
142
143#define IRQ_ATTR_RO(_name) \
144static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
145
146static ssize_t per_cpu_count_show(struct kobject *kobj,
147 struct kobj_attribute *attr, char *buf)
148{
149 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
150 ssize_t ret = 0;
151 char *p = "";
152 int cpu;
153
154 for_each_possible_cpu(cpu) {
155 unsigned int c = irq_desc_kstat_cpu(desc, cpu);
156
157 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
158 p = ",";
159 }
160
161 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
162 return ret;
163}
164IRQ_ATTR_RO(per_cpu_count);
165
166static ssize_t chip_name_show(struct kobject *kobj,
167 struct kobj_attribute *attr, char *buf)
168{
169 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
170 ssize_t ret = 0;
171
172 raw_spin_lock_irq(&desc->lock);
173 if (desc->irq_data.chip && desc->irq_data.chip->name) {
174 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
175 desc->irq_data.chip->name);
176 }
177 raw_spin_unlock_irq(&desc->lock);
178
179 return ret;
180}
181IRQ_ATTR_RO(chip_name);
182
183static ssize_t hwirq_show(struct kobject *kobj,
184 struct kobj_attribute *attr, char *buf)
185{
186 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
187 ssize_t ret = 0;
188
189 raw_spin_lock_irq(&desc->lock);
190 if (desc->irq_data.domain)
191 ret = sprintf(buf, "%lu\n", desc->irq_data.hwirq);
192 raw_spin_unlock_irq(&desc->lock);
193
194 return ret;
195}
196IRQ_ATTR_RO(hwirq);
197
198static ssize_t type_show(struct kobject *kobj,
199 struct kobj_attribute *attr, char *buf)
200{
201 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
202 ssize_t ret = 0;
203
204 raw_spin_lock_irq(&desc->lock);
205 ret = sprintf(buf, "%s\n",
206 irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
207 raw_spin_unlock_irq(&desc->lock);
208
209 return ret;
210
211}
212IRQ_ATTR_RO(type);
213
214static ssize_t wakeup_show(struct kobject *kobj,
215 struct kobj_attribute *attr, char *buf)
216{
217 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
218 ssize_t ret = 0;
219
220 raw_spin_lock_irq(&desc->lock);
221 ret = sprintf(buf, "%s\n",
222 irqd_is_wakeup_set(&desc->irq_data) ? "enabled" : "disabled");
223 raw_spin_unlock_irq(&desc->lock);
224
225 return ret;
226
227}
228IRQ_ATTR_RO(wakeup);
229
230static ssize_t name_show(struct kobject *kobj,
231 struct kobj_attribute *attr, char *buf)
232{
233 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
234 ssize_t ret = 0;
235
236 raw_spin_lock_irq(&desc->lock);
237 if (desc->name)
238 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
239 raw_spin_unlock_irq(&desc->lock);
240
241 return ret;
242}
243IRQ_ATTR_RO(name);
244
245static ssize_t actions_show(struct kobject *kobj,
246 struct kobj_attribute *attr, char *buf)
247{
248 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
249 struct irqaction *action;
250 ssize_t ret = 0;
251 char *p = "";
252
253 raw_spin_lock_irq(&desc->lock);
254 for_each_action_of_desc(desc, action) {
255 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
256 p, action->name);
257 p = ",";
258 }
259 raw_spin_unlock_irq(&desc->lock);
260
261 if (ret)
262 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
263
264 return ret;
265}
266IRQ_ATTR_RO(actions);
267
268static struct attribute *irq_attrs[] = {
269 &per_cpu_count_attr.attr,
270 &chip_name_attr.attr,
271 &hwirq_attr.attr,
272 &type_attr.attr,
273 &wakeup_attr.attr,
274 &name_attr.attr,
275 &actions_attr.attr,
276 NULL
277};
278ATTRIBUTE_GROUPS(irq);
279
280static struct kobj_type irq_kobj_type = {
281 .release = irq_kobj_release,
282 .sysfs_ops = &kobj_sysfs_ops,
283 .default_groups = irq_groups,
284};
285
286static void irq_sysfs_add(int irq, struct irq_desc *desc)
287{
288 if (irq_kobj_base) {
289 /*
290 * Continue even in case of failure as this is nothing
291 * crucial and failures in the late irq_sysfs_init()
292 * cannot be rolled back.
293 */
294 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
295 pr_warn("Failed to add kobject for irq %d\n", irq);
296 else
297 desc->istate |= IRQS_SYSFS;
298 }
299}
300
301static void irq_sysfs_del(struct irq_desc *desc)
302{
303 /*
304 * Only invoke kobject_del() when kobject_add() was successfully
305 * invoked for the descriptor. This covers both early boot, where
306 * sysfs is not initialized yet, and the case of a failed
307 * kobject_add() invocation.
308 */
309 if (desc->istate & IRQS_SYSFS)
310 kobject_del(&desc->kobj);
311}
312
313static int __init irq_sysfs_init(void)
314{
315 struct irq_desc *desc;
316 int irq;
317
318 /* Prevent concurrent irq alloc/free */
319 irq_lock_sparse();
320
321 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
322 if (!irq_kobj_base) {
323 irq_unlock_sparse();
324 return -ENOMEM;
325 }
326
327 /* Add the already allocated interrupts */
328 for_each_irq_desc(irq, desc)
329 irq_sysfs_add(irq, desc);
330 irq_unlock_sparse();
331
332 return 0;
333}
334postcore_initcall(irq_sysfs_init);
335
336#else /* !CONFIG_SYSFS */
337
338static struct kobj_type irq_kobj_type = {
339 .release = irq_kobj_release,
340};
341
342static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
343static void irq_sysfs_del(struct irq_desc *desc) {}
344
345#endif /* CONFIG_SYSFS */
346
347static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
348
349static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
350{
351 radix_tree_insert(&irq_desc_tree, irq, desc);
352}
353
354struct irq_desc *irq_to_desc(unsigned int irq)
355{
356 return radix_tree_lookup(&irq_desc_tree, irq);
357}
358#ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
359EXPORT_SYMBOL_GPL(irq_to_desc);
360#endif
361
362static void delete_irq_desc(unsigned int irq)
363{
364 radix_tree_delete(&irq_desc_tree, irq);
365}
366
367#ifdef CONFIG_SMP
368static void free_masks(struct irq_desc *desc)
369{
370#ifdef CONFIG_GENERIC_PENDING_IRQ
371 free_cpumask_var(desc->pending_mask);
372#endif
373 free_cpumask_var(desc->irq_common_data.affinity);
374#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
375 free_cpumask_var(desc->irq_common_data.effective_affinity);
376#endif
377}
378#else
379static inline void free_masks(struct irq_desc *desc) { }
380#endif
381
382void irq_lock_sparse(void)
383{
384 mutex_lock(&sparse_irq_lock);
385}
386
387void irq_unlock_sparse(void)
388{
389 mutex_unlock(&sparse_irq_lock);
390}
391
392static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
393 const struct cpumask *affinity,
394 struct module *owner)
395{
396 struct irq_desc *desc;
397
398 desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
399 if (!desc)
400 return NULL;
401 /* allocate based on nr_cpu_ids */
402 desc->kstat_irqs = alloc_percpu(unsigned int);
403 if (!desc->kstat_irqs)
404 goto err_desc;
405
406 if (alloc_masks(desc, node))
407 goto err_kstat;
408
409 raw_spin_lock_init(&desc->lock);
410 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
411 mutex_init(&desc->request_mutex);
412 init_rcu_head(&desc->rcu);
413 init_waitqueue_head(&desc->wait_for_threads);
414
415 desc_set_defaults(irq, desc, node, affinity, owner);
416 irqd_set(&desc->irq_data, flags);
417 kobject_init(&desc->kobj, &irq_kobj_type);
418
419 return desc;
420
421err_kstat:
422 free_percpu(desc->kstat_irqs);
423err_desc:
424 kfree(desc);
425 return NULL;
426}
427
428static void irq_kobj_release(struct kobject *kobj)
429{
430 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
431
432 free_masks(desc);
433 free_percpu(desc->kstat_irqs);
434 kfree(desc);
435}
436
437static void delayed_free_desc(struct rcu_head *rhp)
438{
439 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
440
441 kobject_put(&desc->kobj);
442}
443
444static void free_desc(unsigned int irq)
445{
446 struct irq_desc *desc = irq_to_desc(irq);
447
448 irq_remove_debugfs_entry(desc);
449 unregister_irq_proc(irq, desc);
450
451 /*
452 * sparse_irq_lock protects also show_interrupts() and
453 * kstat_irq_usr(). Once we deleted the descriptor from the
454 * sparse tree we can free it. Access in proc will fail to
455 * lookup the descriptor.
456 *
457 * The sysfs entry must be serialized against a concurrent
458 * irq_sysfs_init() as well.
459 */
460 irq_sysfs_del(desc);
461 delete_irq_desc(irq);
462
463 /*
464 * We free the descriptor, masks and stat fields via RCU. That
465 * allows demultiplex interrupts to do rcu based management of
466 * the child interrupts.
467 * This also allows us to use rcu in kstat_irqs_usr().
468 */
469 call_rcu(&desc->rcu, delayed_free_desc);
470}
471
472static int alloc_descs(unsigned int start, unsigned int cnt, int node,
473 const struct irq_affinity_desc *affinity,
474 struct module *owner)
475{
476 struct irq_desc *desc;
477 int i;
478
479 /* Validate affinity mask(s) */
480 if (affinity) {
481 for (i = 0; i < cnt; i++) {
482 if (cpumask_empty(&affinity[i].mask))
483 return -EINVAL;
484 }
485 }
486
487 for (i = 0; i < cnt; i++) {
488 const struct cpumask *mask = NULL;
489 unsigned int flags = 0;
490
491 if (affinity) {
492 if (affinity->is_managed) {
493 flags = IRQD_AFFINITY_MANAGED |
494 IRQD_MANAGED_SHUTDOWN;
495 }
496 mask = &affinity->mask;
497 node = cpu_to_node(cpumask_first(mask));
498 affinity++;
499 }
500
501 desc = alloc_desc(start + i, node, flags, mask, owner);
502 if (!desc)
503 goto err;
504 irq_insert_desc(start + i, desc);
505 irq_sysfs_add(start + i, desc);
506 irq_add_debugfs_entry(start + i, desc);
507 }
508 bitmap_set(allocated_irqs, start, cnt);
509 return start;
510
511err:
512 for (i--; i >= 0; i--)
513 free_desc(start + i);
514 return -ENOMEM;
515}
516
517static int irq_expand_nr_irqs(unsigned int nr)
518{
519 if (nr > IRQ_BITMAP_BITS)
520 return -ENOMEM;
521 nr_irqs = nr;
522 return 0;
523}
524
525int __init early_irq_init(void)
526{
527 int i, initcnt, node = first_online_node;
528 struct irq_desc *desc;
529
530 init_irq_default_affinity();
531
532 /* Let arch update nr_irqs and return the nr of preallocated irqs */
533 initcnt = arch_probe_nr_irqs();
534 printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
535 NR_IRQS, nr_irqs, initcnt);
536
537 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
538 nr_irqs = IRQ_BITMAP_BITS;
539
540 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
541 initcnt = IRQ_BITMAP_BITS;
542
543 if (initcnt > nr_irqs)
544 nr_irqs = initcnt;
545
546 for (i = 0; i < initcnt; i++) {
547 desc = alloc_desc(i, node, 0, NULL, NULL);
548 set_bit(i, allocated_irqs);
549 irq_insert_desc(i, desc);
550 }
551 return arch_early_irq_init();
552}
553
554#else /* !CONFIG_SPARSE_IRQ */
555
556struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
557 [0 ... NR_IRQS-1] = {
558 .handle_irq = handle_bad_irq,
559 .depth = 1,
560 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
561 }
562};
563
564int __init early_irq_init(void)
565{
566 int count, i, node = first_online_node;
567 struct irq_desc *desc;
568
569 init_irq_default_affinity();
570
571 printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
572
573 desc = irq_desc;
574 count = ARRAY_SIZE(irq_desc);
575
576 for (i = 0; i < count; i++) {
577 desc[i].kstat_irqs = alloc_percpu(unsigned int);
578 alloc_masks(&desc[i], node);
579 raw_spin_lock_init(&desc[i].lock);
580 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
581 mutex_init(&desc[i].request_mutex);
582 init_waitqueue_head(&desc[i].wait_for_threads);
583 desc_set_defaults(i, &desc[i], node, NULL, NULL);
584 }
585 return arch_early_irq_init();
586}
587
588struct irq_desc *irq_to_desc(unsigned int irq)
589{
590 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
591}
592EXPORT_SYMBOL(irq_to_desc);
593
594static void free_desc(unsigned int irq)
595{
596 struct irq_desc *desc = irq_to_desc(irq);
597 unsigned long flags;
598
599 raw_spin_lock_irqsave(&desc->lock, flags);
600 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
601 raw_spin_unlock_irqrestore(&desc->lock, flags);
602}
603
604static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
605 const struct irq_affinity_desc *affinity,
606 struct module *owner)
607{
608 u32 i;
609
610 for (i = 0; i < cnt; i++) {
611 struct irq_desc *desc = irq_to_desc(start + i);
612
613 desc->owner = owner;
614 }
615 bitmap_set(allocated_irqs, start, cnt);
616 return start;
617}
618
619static int irq_expand_nr_irqs(unsigned int nr)
620{
621 return -ENOMEM;
622}
623
624void irq_mark_irq(unsigned int irq)
625{
626 mutex_lock(&sparse_irq_lock);
627 bitmap_set(allocated_irqs, irq, 1);
628 mutex_unlock(&sparse_irq_lock);
629}
630
631#ifdef CONFIG_GENERIC_IRQ_LEGACY
632void irq_init_desc(unsigned int irq)
633{
634 free_desc(irq);
635}
636#endif
637
638#endif /* !CONFIG_SPARSE_IRQ */
639
640int handle_irq_desc(struct irq_desc *desc)
641{
642 struct irq_data *data;
643
644 if (!desc)
645 return -EINVAL;
646
647 data = irq_desc_get_irq_data(desc);
648 if (WARN_ON_ONCE(!in_hardirq() && handle_enforce_irqctx(data)))
649 return -EPERM;
650
651 generic_handle_irq_desc(desc);
652 return 0;
653}
654
655/**
656 * generic_handle_irq - Invoke the handler for a particular irq
657 * @irq: The irq number to handle
658 *
659 * Returns: 0 on success, or -EINVAL if conversion has failed
660 *
661 * This function must be called from an IRQ context with irq regs
662 * initialized.
663 */
664int generic_handle_irq(unsigned int irq)
665{
666 return handle_irq_desc(irq_to_desc(irq));
667}
668EXPORT_SYMBOL_GPL(generic_handle_irq);
669
670/**
671 * generic_handle_irq_safe - Invoke the handler for a particular irq from any
672 * context.
673 * @irq: The irq number to handle
674 *
675 * Returns: 0 on success, a negative value on error.
676 *
677 * This function can be called from any context (IRQ or process context). It
678 * will report an error if not invoked from IRQ context and the irq has been
679 * marked to enforce IRQ-context only.
680 */
681int generic_handle_irq_safe(unsigned int irq)
682{
683 unsigned long flags;
684 int ret;
685
686 local_irq_save(flags);
687 ret = handle_irq_desc(irq_to_desc(irq));
688 local_irq_restore(flags);
689 return ret;
690}
691EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
692
693#ifdef CONFIG_IRQ_DOMAIN
694/**
695 * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
696 * to a domain.
697 * @domain: The domain where to perform the lookup
698 * @hwirq: The HW irq number to convert to a logical one
699 *
700 * Returns: 0 on success, or -EINVAL if conversion has failed
701 *
702 * This function must be called from an IRQ context with irq regs
703 * initialized.
704 */
705int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
706{
707 return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
708}
709EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
710
711 /**
712 * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
713 * to a domain from any context.
714 * @domain: The domain where to perform the lookup
715 * @hwirq: The HW irq number to convert to a logical one
716 *
717 * Returns: 0 on success, a negative value on error.
718 *
719 * This function can be called from any context (IRQ or process
720 * context). If the interrupt is marked as 'enforce IRQ-context only' then
721 * the function must be invoked from hard interrupt context.
722 */
723int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
724{
725 unsigned long flags;
726 int ret;
727
728 local_irq_save(flags);
729 ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
730 local_irq_restore(flags);
731 return ret;
732}
733EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
734
735/**
736 * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
737 * to a domain.
738 * @domain: The domain where to perform the lookup
739 * @hwirq: The HW irq number to convert to a logical one
740 *
741 * Returns: 0 on success, or -EINVAL if conversion has failed
742 *
743 * This function must be called from an NMI context with irq regs
744 * initialized.
745 **/
746int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq)
747{
748 WARN_ON_ONCE(!in_nmi());
749 return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
750}
751#endif
752
753/* Dynamic interrupt handling */
754
755/**
756 * irq_free_descs - free irq descriptors
757 * @from: Start of descriptor range
758 * @cnt: Number of consecutive irqs to free
759 */
760void irq_free_descs(unsigned int from, unsigned int cnt)
761{
762 int i;
763
764 if (from >= nr_irqs || (from + cnt) > nr_irqs)
765 return;
766
767 mutex_lock(&sparse_irq_lock);
768 for (i = 0; i < cnt; i++)
769 free_desc(from + i);
770
771 bitmap_clear(allocated_irqs, from, cnt);
772 mutex_unlock(&sparse_irq_lock);
773}
774EXPORT_SYMBOL_GPL(irq_free_descs);
775
776/**
777 * __irq_alloc_descs - allocate and initialize a range of irq descriptors
778 * @irq: Allocate for specific irq number if irq >= 0
779 * @from: Start the search from this irq number
780 * @cnt: Number of consecutive irqs to allocate.
781 * @node: Preferred node on which the irq descriptor should be allocated
782 * @owner: Owning module (can be NULL)
783 * @affinity: Optional pointer to an affinity mask array of size @cnt which
784 * hints where the irq descriptors should be allocated and which
785 * default affinities to use
786 *
787 * Returns the first irq number or error code
788 */
789int __ref
790__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
791 struct module *owner, const struct irq_affinity_desc *affinity)
792{
793 int start, ret;
794
795 if (!cnt)
796 return -EINVAL;
797
798 if (irq >= 0) {
799 if (from > irq)
800 return -EINVAL;
801 from = irq;
802 } else {
803 /*
804 * For interrupts which are freely allocated the
805 * architecture can force a lower bound to the @from
806 * argument. x86 uses this to exclude the GSI space.
807 */
808 from = arch_dynirq_lower_bound(from);
809 }
810
811 mutex_lock(&sparse_irq_lock);
812
813 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
814 from, cnt, 0);
815 ret = -EEXIST;
816 if (irq >=0 && start != irq)
817 goto unlock;
818
819 if (start + cnt > nr_irqs) {
820 ret = irq_expand_nr_irqs(start + cnt);
821 if (ret)
822 goto unlock;
823 }
824 ret = alloc_descs(start, cnt, node, affinity, owner);
825unlock:
826 mutex_unlock(&sparse_irq_lock);
827 return ret;
828}
829EXPORT_SYMBOL_GPL(__irq_alloc_descs);
830
831/**
832 * irq_get_next_irq - get next allocated irq number
833 * @offset: where to start the search
834 *
835 * Returns next irq number after offset or nr_irqs if none is found.
836 */
837unsigned int irq_get_next_irq(unsigned int offset)
838{
839 return find_next_bit(allocated_irqs, nr_irqs, offset);
840}
841
842struct irq_desc *
843__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
844 unsigned int check)
845{
846 struct irq_desc *desc = irq_to_desc(irq);
847
848 if (desc) {
849 if (check & _IRQ_DESC_CHECK) {
850 if ((check & _IRQ_DESC_PERCPU) &&
851 !irq_settings_is_per_cpu_devid(desc))
852 return NULL;
853
854 if (!(check & _IRQ_DESC_PERCPU) &&
855 irq_settings_is_per_cpu_devid(desc))
856 return NULL;
857 }
858
859 if (bus)
860 chip_bus_lock(desc);
861 raw_spin_lock_irqsave(&desc->lock, *flags);
862 }
863 return desc;
864}
865
866void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
867 __releases(&desc->lock)
868{
869 raw_spin_unlock_irqrestore(&desc->lock, flags);
870 if (bus)
871 chip_bus_sync_unlock(desc);
872}
873
874int irq_set_percpu_devid_partition(unsigned int irq,
875 const struct cpumask *affinity)
876{
877 struct irq_desc *desc = irq_to_desc(irq);
878
879 if (!desc)
880 return -EINVAL;
881
882 if (desc->percpu_enabled)
883 return -EINVAL;
884
885 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
886
887 if (!desc->percpu_enabled)
888 return -ENOMEM;
889
890 if (affinity)
891 desc->percpu_affinity = affinity;
892 else
893 desc->percpu_affinity = cpu_possible_mask;
894
895 irq_set_percpu_devid_flags(irq);
896 return 0;
897}
898
899int irq_set_percpu_devid(unsigned int irq)
900{
901 return irq_set_percpu_devid_partition(irq, NULL);
902}
903
904int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
905{
906 struct irq_desc *desc = irq_to_desc(irq);
907
908 if (!desc || !desc->percpu_enabled)
909 return -EINVAL;
910
911 if (affinity)
912 cpumask_copy(affinity, desc->percpu_affinity);
913
914 return 0;
915}
916EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
917
918void kstat_incr_irq_this_cpu(unsigned int irq)
919{
920 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
921}
922
923/**
924 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
925 * @irq: The interrupt number
926 * @cpu: The cpu number
927 *
928 * Returns the sum of interrupt counts on @cpu since boot for
929 * @irq. The caller must ensure that the interrupt is not removed
930 * concurrently.
931 */
932unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
933{
934 struct irq_desc *desc = irq_to_desc(irq);
935
936 return desc && desc->kstat_irqs ?
937 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
938}
939
940static bool irq_is_nmi(struct irq_desc *desc)
941{
942 return desc->istate & IRQS_NMI;
943}
944
945static unsigned int kstat_irqs(unsigned int irq)
946{
947 struct irq_desc *desc = irq_to_desc(irq);
948 unsigned int sum = 0;
949 int cpu;
950
951 if (!desc || !desc->kstat_irqs)
952 return 0;
953 if (!irq_settings_is_per_cpu_devid(desc) &&
954 !irq_settings_is_per_cpu(desc) &&
955 !irq_is_nmi(desc))
956 return data_race(desc->tot_count);
957
958 for_each_possible_cpu(cpu)
959 sum += data_race(*per_cpu_ptr(desc->kstat_irqs, cpu));
960 return sum;
961}
962
963/**
964 * kstat_irqs_usr - Get the statistics for an interrupt from thread context
965 * @irq: The interrupt number
966 *
967 * Returns the sum of interrupt counts on all cpus since boot for @irq.
968 *
969 * It uses rcu to protect the access since a concurrent removal of an
970 * interrupt descriptor is observing an rcu grace period before
971 * delayed_free_desc()/irq_kobj_release().
972 */
973unsigned int kstat_irqs_usr(unsigned int irq)
974{
975 unsigned int sum;
976
977 rcu_read_lock();
978 sum = kstat_irqs(irq);
979 rcu_read_unlock();
980 return sum;
981}
982
983#ifdef CONFIG_LOCKDEP
984void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
985 struct lock_class_key *request_class)
986{
987 struct irq_desc *desc = irq_to_desc(irq);
988
989 if (desc) {
990 lockdep_set_class(&desc->lock, lock_class);
991 lockdep_set_class(&desc->request_mutex, request_class);
992 }
993}
994EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
995#endif
1/*
2 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
3 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
4 *
5 * This file contains the interrupt descriptor management code
6 *
7 * Detailed information is available in Documentation/DocBook/genericirq
8 *
9 */
10#include <linux/irq.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/interrupt.h>
14#include <linux/kernel_stat.h>
15#include <linux/radix-tree.h>
16#include <linux/bitmap.h>
17
18#include "internals.h"
19
20/*
21 * lockdep: we want to handle all irq_desc locks as a single lock-class:
22 */
23static struct lock_class_key irq_desc_lock_class;
24
25#if defined(CONFIG_SMP)
26static void __init init_irq_default_affinity(void)
27{
28 alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
29 cpumask_setall(irq_default_affinity);
30}
31#else
32static void __init init_irq_default_affinity(void)
33{
34}
35#endif
36
37#ifdef CONFIG_SMP
38static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
39{
40 if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node))
41 return -ENOMEM;
42
43#ifdef CONFIG_GENERIC_PENDING_IRQ
44 if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
45 free_cpumask_var(desc->irq_data.affinity);
46 return -ENOMEM;
47 }
48#endif
49 return 0;
50}
51
52static void desc_smp_init(struct irq_desc *desc, int node)
53{
54 desc->irq_data.node = node;
55 cpumask_copy(desc->irq_data.affinity, irq_default_affinity);
56#ifdef CONFIG_GENERIC_PENDING_IRQ
57 cpumask_clear(desc->pending_mask);
58#endif
59}
60
61static inline int desc_node(struct irq_desc *desc)
62{
63 return desc->irq_data.node;
64}
65
66#else
67static inline int
68alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
69static inline void desc_smp_init(struct irq_desc *desc, int node) { }
70static inline int desc_node(struct irq_desc *desc) { return 0; }
71#endif
72
73static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
74 struct module *owner)
75{
76 int cpu;
77
78 desc->irq_data.irq = irq;
79 desc->irq_data.chip = &no_irq_chip;
80 desc->irq_data.chip_data = NULL;
81 desc->irq_data.handler_data = NULL;
82 desc->irq_data.msi_desc = NULL;
83 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
84 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
85 desc->handle_irq = handle_bad_irq;
86 desc->depth = 1;
87 desc->irq_count = 0;
88 desc->irqs_unhandled = 0;
89 desc->name = NULL;
90 desc->owner = owner;
91 for_each_possible_cpu(cpu)
92 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
93 desc_smp_init(desc, node);
94}
95
96int nr_irqs = NR_IRQS;
97EXPORT_SYMBOL_GPL(nr_irqs);
98
99static DEFINE_MUTEX(sparse_irq_lock);
100static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
101
102#ifdef CONFIG_SPARSE_IRQ
103
104static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
105
106static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
107{
108 radix_tree_insert(&irq_desc_tree, irq, desc);
109}
110
111struct irq_desc *irq_to_desc(unsigned int irq)
112{
113 return radix_tree_lookup(&irq_desc_tree, irq);
114}
115EXPORT_SYMBOL(irq_to_desc);
116
117static void delete_irq_desc(unsigned int irq)
118{
119 radix_tree_delete(&irq_desc_tree, irq);
120}
121
122#ifdef CONFIG_SMP
123static void free_masks(struct irq_desc *desc)
124{
125#ifdef CONFIG_GENERIC_PENDING_IRQ
126 free_cpumask_var(desc->pending_mask);
127#endif
128 free_cpumask_var(desc->irq_data.affinity);
129}
130#else
131static inline void free_masks(struct irq_desc *desc) { }
132#endif
133
134static struct irq_desc *alloc_desc(int irq, int node, struct module *owner)
135{
136 struct irq_desc *desc;
137 gfp_t gfp = GFP_KERNEL;
138
139 desc = kzalloc_node(sizeof(*desc), gfp, node);
140 if (!desc)
141 return NULL;
142 /* allocate based on nr_cpu_ids */
143 desc->kstat_irqs = alloc_percpu(unsigned int);
144 if (!desc->kstat_irqs)
145 goto err_desc;
146
147 if (alloc_masks(desc, gfp, node))
148 goto err_kstat;
149
150 raw_spin_lock_init(&desc->lock);
151 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
152
153 desc_set_defaults(irq, desc, node, owner);
154
155 return desc;
156
157err_kstat:
158 free_percpu(desc->kstat_irqs);
159err_desc:
160 kfree(desc);
161 return NULL;
162}
163
164static void free_desc(unsigned int irq)
165{
166 struct irq_desc *desc = irq_to_desc(irq);
167
168 unregister_irq_proc(irq, desc);
169
170 mutex_lock(&sparse_irq_lock);
171 delete_irq_desc(irq);
172 mutex_unlock(&sparse_irq_lock);
173
174 free_masks(desc);
175 free_percpu(desc->kstat_irqs);
176 kfree(desc);
177}
178
179static int alloc_descs(unsigned int start, unsigned int cnt, int node,
180 struct module *owner)
181{
182 struct irq_desc *desc;
183 int i;
184
185 for (i = 0; i < cnt; i++) {
186 desc = alloc_desc(start + i, node, owner);
187 if (!desc)
188 goto err;
189 mutex_lock(&sparse_irq_lock);
190 irq_insert_desc(start + i, desc);
191 mutex_unlock(&sparse_irq_lock);
192 }
193 return start;
194
195err:
196 for (i--; i >= 0; i--)
197 free_desc(start + i);
198
199 mutex_lock(&sparse_irq_lock);
200 bitmap_clear(allocated_irqs, start, cnt);
201 mutex_unlock(&sparse_irq_lock);
202 return -ENOMEM;
203}
204
205static int irq_expand_nr_irqs(unsigned int nr)
206{
207 if (nr > IRQ_BITMAP_BITS)
208 return -ENOMEM;
209 nr_irqs = nr;
210 return 0;
211}
212
213int __init early_irq_init(void)
214{
215 int i, initcnt, node = first_online_node;
216 struct irq_desc *desc;
217
218 init_irq_default_affinity();
219
220 /* Let arch update nr_irqs and return the nr of preallocated irqs */
221 initcnt = arch_probe_nr_irqs();
222 printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
223
224 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
225 nr_irqs = IRQ_BITMAP_BITS;
226
227 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
228 initcnt = IRQ_BITMAP_BITS;
229
230 if (initcnt > nr_irqs)
231 nr_irqs = initcnt;
232
233 for (i = 0; i < initcnt; i++) {
234 desc = alloc_desc(i, node, NULL);
235 set_bit(i, allocated_irqs);
236 irq_insert_desc(i, desc);
237 }
238 return arch_early_irq_init();
239}
240
241#else /* !CONFIG_SPARSE_IRQ */
242
243struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
244 [0 ... NR_IRQS-1] = {
245 .handle_irq = handle_bad_irq,
246 .depth = 1,
247 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
248 }
249};
250
251int __init early_irq_init(void)
252{
253 int count, i, node = first_online_node;
254 struct irq_desc *desc;
255
256 init_irq_default_affinity();
257
258 printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
259
260 desc = irq_desc;
261 count = ARRAY_SIZE(irq_desc);
262
263 for (i = 0; i < count; i++) {
264 desc[i].kstat_irqs = alloc_percpu(unsigned int);
265 alloc_masks(&desc[i], GFP_KERNEL, node);
266 raw_spin_lock_init(&desc[i].lock);
267 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
268 desc_set_defaults(i, &desc[i], node, NULL);
269 }
270 return arch_early_irq_init();
271}
272
273struct irq_desc *irq_to_desc(unsigned int irq)
274{
275 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
276}
277EXPORT_SYMBOL(irq_to_desc);
278
279static void free_desc(unsigned int irq)
280{
281 dynamic_irq_cleanup(irq);
282}
283
284static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
285 struct module *owner)
286{
287 u32 i;
288
289 for (i = 0; i < cnt; i++) {
290 struct irq_desc *desc = irq_to_desc(start + i);
291
292 desc->owner = owner;
293 }
294 return start;
295}
296
297static int irq_expand_nr_irqs(unsigned int nr)
298{
299 return -ENOMEM;
300}
301
302#endif /* !CONFIG_SPARSE_IRQ */
303
304/**
305 * generic_handle_irq - Invoke the handler for a particular irq
306 * @irq: The irq number to handle
307 *
308 */
309int generic_handle_irq(unsigned int irq)
310{
311 struct irq_desc *desc = irq_to_desc(irq);
312
313 if (!desc)
314 return -EINVAL;
315 generic_handle_irq_desc(irq, desc);
316 return 0;
317}
318EXPORT_SYMBOL_GPL(generic_handle_irq);
319
320/* Dynamic interrupt handling */
321
322/**
323 * irq_free_descs - free irq descriptors
324 * @from: Start of descriptor range
325 * @cnt: Number of consecutive irqs to free
326 */
327void irq_free_descs(unsigned int from, unsigned int cnt)
328{
329 int i;
330
331 if (from >= nr_irqs || (from + cnt) > nr_irqs)
332 return;
333
334 for (i = 0; i < cnt; i++)
335 free_desc(from + i);
336
337 mutex_lock(&sparse_irq_lock);
338 bitmap_clear(allocated_irqs, from, cnt);
339 mutex_unlock(&sparse_irq_lock);
340}
341EXPORT_SYMBOL_GPL(irq_free_descs);
342
343/**
344 * irq_alloc_descs - allocate and initialize a range of irq descriptors
345 * @irq: Allocate for specific irq number if irq >= 0
346 * @from: Start the search from this irq number
347 * @cnt: Number of consecutive irqs to allocate.
348 * @node: Preferred node on which the irq descriptor should be allocated
349 * @owner: Owning module (can be NULL)
350 *
351 * Returns the first irq number or error code
352 */
353int __ref
354__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
355 struct module *owner)
356{
357 int start, ret;
358
359 if (!cnt)
360 return -EINVAL;
361
362 if (irq >= 0) {
363 if (from > irq)
364 return -EINVAL;
365 from = irq;
366 } else {
367 /*
368 * For interrupts which are freely allocated the
369 * architecture can force a lower bound to the @from
370 * argument. x86 uses this to exclude the GSI space.
371 */
372 from = arch_dynirq_lower_bound(from);
373 }
374
375 mutex_lock(&sparse_irq_lock);
376
377 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
378 from, cnt, 0);
379 ret = -EEXIST;
380 if (irq >=0 && start != irq)
381 goto err;
382
383 if (start + cnt > nr_irqs) {
384 ret = irq_expand_nr_irqs(start + cnt);
385 if (ret)
386 goto err;
387 }
388
389 bitmap_set(allocated_irqs, start, cnt);
390 mutex_unlock(&sparse_irq_lock);
391 return alloc_descs(start, cnt, node, owner);
392
393err:
394 mutex_unlock(&sparse_irq_lock);
395 return ret;
396}
397EXPORT_SYMBOL_GPL(__irq_alloc_descs);
398
399/**
400 * irq_reserve_irqs - mark irqs allocated
401 * @from: mark from irq number
402 * @cnt: number of irqs to mark
403 *
404 * Returns 0 on success or an appropriate error code
405 */
406int irq_reserve_irqs(unsigned int from, unsigned int cnt)
407{
408 unsigned int start;
409 int ret = 0;
410
411 if (!cnt || (from + cnt) > nr_irqs)
412 return -EINVAL;
413
414 mutex_lock(&sparse_irq_lock);
415 start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
416 if (start == from)
417 bitmap_set(allocated_irqs, start, cnt);
418 else
419 ret = -EEXIST;
420 mutex_unlock(&sparse_irq_lock);
421 return ret;
422}
423
424/**
425 * irq_get_next_irq - get next allocated irq number
426 * @offset: where to start the search
427 *
428 * Returns next irq number after offset or nr_irqs if none is found.
429 */
430unsigned int irq_get_next_irq(unsigned int offset)
431{
432 return find_next_bit(allocated_irqs, nr_irqs, offset);
433}
434
435struct irq_desc *
436__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
437 unsigned int check)
438{
439 struct irq_desc *desc = irq_to_desc(irq);
440
441 if (desc) {
442 if (check & _IRQ_DESC_CHECK) {
443 if ((check & _IRQ_DESC_PERCPU) &&
444 !irq_settings_is_per_cpu_devid(desc))
445 return NULL;
446
447 if (!(check & _IRQ_DESC_PERCPU) &&
448 irq_settings_is_per_cpu_devid(desc))
449 return NULL;
450 }
451
452 if (bus)
453 chip_bus_lock(desc);
454 raw_spin_lock_irqsave(&desc->lock, *flags);
455 }
456 return desc;
457}
458
459void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
460{
461 raw_spin_unlock_irqrestore(&desc->lock, flags);
462 if (bus)
463 chip_bus_sync_unlock(desc);
464}
465
466int irq_set_percpu_devid(unsigned int irq)
467{
468 struct irq_desc *desc = irq_to_desc(irq);
469
470 if (!desc)
471 return -EINVAL;
472
473 if (desc->percpu_enabled)
474 return -EINVAL;
475
476 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
477
478 if (!desc->percpu_enabled)
479 return -ENOMEM;
480
481 irq_set_percpu_devid_flags(irq);
482 return 0;
483}
484
485/**
486 * dynamic_irq_cleanup - cleanup a dynamically allocated irq
487 * @irq: irq number to initialize
488 */
489void dynamic_irq_cleanup(unsigned int irq)
490{
491 struct irq_desc *desc = irq_to_desc(irq);
492 unsigned long flags;
493
494 raw_spin_lock_irqsave(&desc->lock, flags);
495 desc_set_defaults(irq, desc, desc_node(desc), NULL);
496 raw_spin_unlock_irqrestore(&desc->lock, flags);
497}
498
499void kstat_incr_irq_this_cpu(unsigned int irq)
500{
501 kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
502}
503
504unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
505{
506 struct irq_desc *desc = irq_to_desc(irq);
507
508 return desc && desc->kstat_irqs ?
509 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
510}
511
512unsigned int kstat_irqs(unsigned int irq)
513{
514 struct irq_desc *desc = irq_to_desc(irq);
515 int cpu;
516 int sum = 0;
517
518 if (!desc || !desc->kstat_irqs)
519 return 0;
520 for_each_possible_cpu(cpu)
521 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
522 return sum;
523}