diff options
Diffstat (limited to 'kernel/irq/irqdesc.c')
-rw-r--r-- | kernel/irq/irqdesc.c | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c new file mode 100644 index 0000000..fbf8cfa --- /dev/null +++ b/kernel/irq/irqdesc.c @@ -0,0 +1,269 @@ +/* + * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar + * Copyright (C) 2005-2006, Thomas Gleixner, Russell King + * + * This file contains the interrupt descriptor management code + * + * Detailed information is available in Documentation/DocBook/genericirq + * + */ +#include <linux/irq.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/radix-tree.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; + +#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS) +static void __init init_irq_default_affinity(void) +{ + alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT); + cpumask_setall(irq_default_affinity); +} +#else +static void __init init_irq_default_affinity(void) +{ +} +#endif + +int nr_irqs = NR_IRQS; +EXPORT_SYMBOL_GPL(nr_irqs); + +#ifdef CONFIG_SPARSE_IRQ + +static struct irq_desc irq_desc_init = { + .status = IRQ_DISABLED, + .handle_irq = handle_bad_irq, + .depth = 1, + .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc_init.lock), +}; + +void __ref init_kstat_irqs(struct irq_desc *desc, int node, int nr) +{ + void *ptr; + + 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 node %d\n", node); + desc->kstat_irqs = ptr; + } +} + +static void init_one_irq_desc(int irq, struct irq_desc *desc, int node) +{ + memcpy(desc, &irq_desc_init, sizeof(struct irq_desc)); + + raw_spin_lock_init(&desc->lock); + desc->irq_data.irq = irq; +#ifdef CONFIG_SMP + desc->irq_data.node = node; +#endif + lockdep_set_class(&desc->lock, &irq_desc_lock_class); + init_kstat_irqs(desc, node, nr_cpu_ids); + if (!desc->kstat_irqs) { + printk(KERN_ERR "can not alloc kstat_irqs\n"); + BUG_ON(1); + } + if (!alloc_desc_masks(desc, node, false)) { + printk(KERN_ERR "can not alloc irq_desc cpumasks\n"); + BUG_ON(1); + } + init_desc_masks(desc); + arch_init_chip_data(desc, node); +} + +/* + * Protect the sparse_irqs: + */ +DEFINE_RAW_SPINLOCK(sparse_irq_lock); + +static RADIX_TREE(irq_desc_tree, GFP_ATOMIC); + +static void set_irq_desc(unsigned int irq, struct irq_desc *desc) +{ + radix_tree_insert(&irq_desc_tree, irq, desc); +} + +struct irq_desc *irq_to_desc(unsigned int irq) +{ + return radix_tree_lookup(&irq_desc_tree, irq); +} + +void replace_irq_desc(unsigned int irq, struct irq_desc *desc) +{ + void **ptr; + + ptr = radix_tree_lookup_slot(&irq_desc_tree, irq); + if (ptr) + radix_tree_replace_slot(ptr, desc); +} + +static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = { + [0 ... NR_IRQS_LEGACY-1] = { + .status = IRQ_DISABLED, + .handle_irq = handle_bad_irq, + .depth = 1, + .lock = __RAW_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 node; + 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); + node = first_online_node; + + /* allocate based on nr_cpu_ids */ + kstat_irqs_legacy = kzalloc_node(NR_IRQS_LEGACY * nr_cpu_ids * + sizeof(int), GFP_NOWAIT, node); + + irq_desc_init.irq_data.chip = &no_irq_chip; + + for (i = 0; i < legacy_count; i++) { + desc[i].irq_data.irq = i; + desc[i].irq_data.chip = &no_irq_chip; +#ifdef CONFIG_SMP + desc[i].irq_data.node = node; +#endif + desc[i].kstat_irqs = kstat_irqs_legacy + i * nr_cpu_ids; + lockdep_set_class(&desc[i].lock, &irq_desc_lock_class); + alloc_desc_masks(&desc[i], node, true); + init_desc_masks(&desc[i]); + set_irq_desc(i, &desc[i]); + } + + return arch_early_irq_init(); +} + +struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node) +{ + struct irq_desc *desc; + unsigned long flags; + + if (irq >= nr_irqs) { + WARN(1, "irq (%d) >= nr_irqs (%d) in irq_to_desc_alloc\n", + irq, nr_irqs); + return NULL; + } + + desc = irq_to_desc(irq); + if (desc) + return desc; + + raw_spin_lock_irqsave(&sparse_irq_lock, flags); + + /* We have to check it to avoid races with another CPU */ + desc = irq_to_desc(irq); + if (desc) + goto out_unlock; + + desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node); + + printk(KERN_DEBUG " alloc irq_desc for %d on node %d\n", irq, node); + if (!desc) { + printk(KERN_ERR "can not alloc irq_desc\n"); + BUG_ON(1); + } + init_one_irq_desc(irq, desc, node); + + set_irq_desc(irq, desc); + +out_unlock: + raw_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, + .handle_irq = handle_bad_irq, + .depth = 1, + .lock = __RAW_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_data.irq = i; + desc[i].irq_data.chip = &no_irq_chip; + alloc_desc_masks(&desc[i], 0, true); + init_desc_masks(&desc[i]); + 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_node(unsigned int irq, int node) +{ + return irq_to_desc(irq); +} +#endif /* !CONFIG_SPARSE_IRQ */ + +void clear_kstat_irqs(struct irq_desc *desc) +{ + memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs))); +} + +void early_init_irq_lock_class(void) +{ + struct irq_desc *desc; + int i; + + for_each_irq_desc(i, desc) { + lockdep_set_class(&desc->lock, &irq_desc_lock_class); + } +} + +unsigned int kstat_irqs_cpu(unsigned int irq, int cpu) +{ + struct irq_desc *desc = irq_to_desc(irq); + return desc ? desc->kstat_irqs[cpu] : 0; +} +EXPORT_SYMBOL(kstat_irqs_cpu); |