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/*
* linux/kernel/irq/handle.c
*
* Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
* Copyright (C) 2005-2006, Thomas Gleixner, Russell King
*
* This file contains the core interrupt handling code.
*
* Detailed information is available in Documentation/DocBook/genericirq
*
*/
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/rculist.h>
#include <linux/hash.h>
#include <trace/irq.h>
#include <linux/bootmem.h>
#include "internals.h"
/*
* lockdep: we want to handle all irq_desc locks as a single lock-class:
*/
struct lock_class_key irq_desc_lock_class;
/**
* handle_bad_irq - handle spurious and unhandled irqs
* @irq: the interrupt number
* @desc: description of the interrupt
*
* Handles spurious and unhandled IRQ's. It also prints a debugmessage.
*/
void handle_bad_irq(unsigned int irq, struct irq_desc *desc)
{
print_irq_desc(irq, desc);
kstat_incr_irqs_this_cpu(irq, desc);
ack_bad_irq(irq);
}
#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
static void __init init_irq_default_affinity(void)
{
alloc_bootmem_cpumask_var(&irq_default_affinity);
cpumask_setall(irq_default_affinity);
}
#else
static void __init init_irq_default_affinity(void)
{
}
#endif
/*
* Linux has a controller-independent interrupt architecture.
* Every controller has a 'controller-template', that is used
* by the main code to do the right thing. Each driver-visible
* interrupt source is transparently wired to the appropriate
* controller. Thus drivers need not be aware of the
* interrupt-controller.
*
* The code is designed to be easily extended with new/different
* interrupt controllers, without having to do assembly magic or
* having to touch the generic code.
*
* Controller mappings for all interrupt sources:
*/
int nr_irqs = NR_IRQS;
EXPORT_SYMBOL_GPL(nr_irqs);
#ifdef CONFIG_SPARSE_IRQ
static struct irq_desc irq_desc_init = {
.irq = -1,
.status = IRQ_DISABLED,
.chip = &no_irq_chip,
.handle_irq = handle_bad_irq,
.depth = 1,
.lock = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
};
void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr)
{
int node;
void *ptr;
node = cpu_to_node(cpu);
ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs), GFP_ATOMIC, node);
/*
* don't overwite if can not get new one
* init_copy_kstat_irqs() could still use old one
*/
if (ptr) {
printk(KERN_DEBUG " alloc kstat_irqs on cpu %d node %d\n",
cpu, node);
desc->kstat_irqs = ptr;
}
}
static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
{
memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));
spin_lock_init(&desc->lock);
desc->irq = irq;
#ifdef CONFIG_SMP
desc->cpu = cpu;
#endif
lockdep_set_class(&desc->lock, &irq_desc_lock_class);
init_kstat_irqs(desc, cpu, nr_cpu_ids);
if (!desc->kstat_irqs) {
printk(KERN_ERR "can not alloc kstat_irqs\n");
BUG_ON(1);
}
if (!init_alloc_desc_masks(desc, cpu, false)) {
printk(KERN_ERR "can not alloc irq_desc cpumasks\n");
BUG_ON(1);
}
arch_init_chip_data(desc, cpu);
}
/*
* Protect the sparse_irqs:
*/
DEFINE_SPINLOCK(sparse_irq_lock);
struct irq_desc **irq_desc_ptrs __read_mostly;
static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
[0 ... NR_IRQS_LEGACY-1] = {
.irq = -1,
.status = IRQ_DISABLED,
.chip = &no_irq_chip,
.handle_irq = handle_bad_irq,
.depth = 1,
.lock = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
}
};
static unsigned int *kstat_irqs_legacy;
int __init early_irq_init(void)
{
struct irq_desc *desc;
int legacy_count;
int i;
init_irq_default_affinity();
/* initialize nr_irqs based on nr_cpu_ids */
arch_probe_nr_irqs();
printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d\n", NR_IRQS, nr_irqs);
desc = irq_desc_legacy;
legacy_count = ARRAY_SIZE(irq_desc_legacy);
/* allocate irq_desc_ptrs array based on nr_irqs */
irq_desc_ptrs = alloc_bootmem(nr_irqs * sizeof(void *));
/* allocate based on nr_cpu_ids */
/* FIXME: invert kstat_irgs, and it'd be a per_cpu_alloc'd thing */
kstat_irqs_legacy = alloc_bootmem(NR_IRQS_LEGACY * nr_cpu_ids *
sizeof(int));
for (i = 0; i < legacy_count; i++) {
desc[i].irq = i;
desc[i].kstat_irqs = kstat_irqs_legacy + i * nr_cpu_ids;
lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
init_alloc_desc_masks(&desc[i], 0, true);
irq_desc_ptrs[i] = desc + i;
}
for (i = legacy_count; i < nr_irqs; i++)
irq_desc_ptrs[i] = NULL;
return arch_early_irq_init();
}
struct irq_desc *irq_to_desc(unsigned int irq)
{
if (irq_desc_ptrs && irq < nr_irqs)
return irq_desc_ptrs[irq];
return NULL;
}
struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
{
struct irq_desc *desc;
unsigned long flags;
int node;
if (irq >= nr_irqs) {
WARN(1, "irq (%d) >= nr_irqs (%d) in irq_to_desc_alloc\n",
irq, nr_irqs);
return NULL;
}
desc = irq_desc_ptrs[irq];
if (desc)
return desc;
spin_lock_irqsave(&sparse_irq_lock, flags);
/* We have to check it to avoid races with another CPU */
desc = irq_desc_ptrs[irq];
if (desc)
goto out_unlock;
node = cpu_to_node(cpu);
desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
printk(KERN_DEBUG " alloc irq_desc for %d on cpu %d node %d\n",
irq, cpu, node);
if (!desc) {
printk(KERN_ERR "can not alloc irq_desc\n");
BUG_ON(1);
}
init_one_irq_desc(irq, desc, cpu);
irq_desc_ptrs[irq] = desc;
out_unlock:
spin_unlock_irqrestore(&sparse_irq_lock, flags);
return desc;
}
#else /* !CONFIG_SPARSE_IRQ */
struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
[0 ... NR_IRQS-1] = {
.status = IRQ_DISABLED,
.chip = &no_irq_chip,
.handle_irq = handle_bad_irq,
.depth = 1,
.lock = __SPIN_LOCK_UNLOCKED(irq_desc->lock),
}
};
static unsigned int kstat_irqs_all[NR_IRQS][NR_CPUS];
int __init early_irq_init(void)
{
struct irq_desc *desc;
int count;
int i;
init_irq_default_affinity();
printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
desc = irq_desc;
count = ARRAY_SIZE(irq_desc);
for (i = 0; i < count; i++) {
desc[i].irq = i;
init_alloc_desc_masks(&desc[i], 0, true);
desc[i].kstat_irqs = kstat_irqs_all[i];
}
return arch_early_irq_init();
}
struct irq_desc *irq_to_desc(unsigned int irq)
{
return (irq < NR_IRQS) ? irq_desc + irq : NULL;
}
struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
{
return irq_to_desc(irq);
}
#endif /* !CONFIG_SPARSE_IRQ */
void clear_kstat_irqs(struct irq_desc *desc)
{
memset(desc->kstat_irqs<
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