diff options
Diffstat (limited to 'kernel/irq')
| -rw-r--r-- | kernel/irq/irqdesc.c | 231 |
1 files changed, 223 insertions, 8 deletions
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 29963f99f24d..4eea48b4f576 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -13,6 +13,7 @@ #include <linux/interrupt.h> #include <linux/kernel_stat.h> #include <linux/radix-tree.h> +#include <linux/bitmap.h> #include "internals.h" @@ -33,9 +34,54 @@ static void __init init_irq_default_affinity(void) } #endif +#ifdef CONFIG_SMP +static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) +{ + if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node)) + return -ENOMEM; + +#ifdef CONFIG_GENERIC_PENDING_IRQ + if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) { + free_cpumask_var(desc->irq_data.affinity); + return -ENOMEM; + } +#endif + return 0; +} + +static void desc_smp_init(struct irq_desc *desc, int node) +{ + desc->node = node; + cpumask_copy(desc->irq_data.affinity, irq_default_affinity); +} + +#else +static inline int +alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; } +static inline void desc_smp_init(struct irq_desc *desc, int node) { } +#endif + +static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node) +{ + desc->irq_data.irq = irq; + desc->irq_data.chip = &no_irq_chip; + desc->irq_data.chip_data = NULL; + desc->irq_data.handler_data = NULL; + desc->irq_data.msi_desc = NULL; + desc->status = IRQ_DEFAULT_INIT_FLAGS; + desc->handle_irq = handle_bad_irq; + desc->depth = 1; + desc->name = NULL; + memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs))); + desc_smp_init(desc, node); +} + int nr_irqs = NR_IRQS; EXPORT_SYMBOL_GPL(nr_irqs); +DEFINE_RAW_SPINLOCK(sparse_irq_lock); +static DECLARE_BITMAP(allocated_irqs, NR_IRQS); + #ifdef CONFIG_SPARSE_IRQ static struct irq_desc irq_desc_init = { @@ -85,14 +131,9 @@ static void init_one_irq_desc(int irq, struct irq_desc *desc, int node) 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) +static void irq_insert_desc(unsigned int irq, struct irq_desc *desc) { radix_tree_insert(&irq_desc_tree, irq, desc); } @@ -111,6 +152,94 @@ void replace_irq_desc(unsigned int irq, struct irq_desc *desc) radix_tree_replace_slot(ptr, desc); } +static void delete_irq_desc(unsigned int irq) +{ + radix_tree_delete(&irq_desc_tree, irq); +} + +#ifdef CONFIG_SMP +static void free_masks(struct irq_desc *desc) +{ +#ifdef CONFIG_GENERIC_PENDING_IRQ + free_cpumask_var(desc->pending_mask); +#endif + free_cpumask_var(desc->affinity); +} +#else +static inline void free_masks(struct irq_desc *desc) { } +#endif + +static struct irq_desc *alloc_desc(int irq, int node) +{ + struct irq_desc *desc; + gfp_t gfp = GFP_KERNEL; + + desc = kzalloc_node(sizeof(*desc), gfp, node); + if (!desc) + return NULL; + /* allocate based on nr_cpu_ids */ + desc->kstat_irqs = kzalloc_node(nr_cpu_ids * sizeof(*desc->kstat_irqs), + gfp, node); + if (!desc->kstat_irqs) + goto err_desc; + + if (alloc_masks(desc, gfp, node)) + goto err_kstat; + + raw_spin_lock_init(&desc->lock); + lockdep_set_class(&desc->lock, &irq_desc_lock_class); + + desc_set_defaults(irq, desc, node); + + return desc; + +err_kstat: + kfree(desc->kstat_irqs); +err_desc: + kfree(desc); + return NULL; +} + +static void free_desc(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + unsigned long flags; + + raw_spin_lock_irqsave(&sparse_irq_lock, flags); + delete_irq_desc(irq); + raw_spin_unlock_irqrestore(&sparse_irq_lock, flags); + + free_masks(desc); + kfree(desc->kstat_irqs); + kfree(desc); +} + +static int alloc_descs(unsigned int start, unsigned int cnt, int node) +{ + struct irq_desc *desc; + unsigned long flags; + int i; + + for (i = 0; i < cnt; i++) { + desc = alloc_desc(start + i, node); + if (!desc) + goto err; + raw_spin_lock_irqsave(&sparse_irq_lock, flags); + irq_insert_desc(start + i, desc); + raw_spin_unlock_irqrestore(&sparse_irq_lock, flags); + } + return start; + +err: + for (i--; i >= 0; i--) + free_desc(start + i); + + raw_spin_lock_irqsave(&sparse_irq_lock, flags); + bitmap_clear(allocated_irqs, start, cnt); + raw_spin_unlock_irqrestore(&sparse_irq_lock, flags); + return -ENOMEM; +} + static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = { [0 ... NR_IRQS_LEGACY-1] = { .status = IRQ_DEFAULT_INIT_FLAGS, @@ -155,7 +284,7 @@ int __init early_irq_init(void) 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]); + irq_insert_desc(i, &desc[i]); } return arch_early_irq_init(); @@ -192,7 +321,7 @@ struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node) } init_one_irq_desc(irq, desc, node); - set_irq_desc(irq, desc); + irq_insert_desc(irq, desc); out_unlock: raw_spin_unlock_irqrestore(&sparse_irq_lock, flags); @@ -245,8 +374,94 @@ struct irq_desc *irq_to_desc_alloc_node(unsigned int irq, int node) { return irq_to_desc(irq); } + +#ifdef CONFIG_SMP +static inline int desc_node(struct irq_desc *desc) +{ + return desc->irq_data.node; +} +#else +static inline int desc_node(struct irq_desc *desc) { return 0; } +#endif + +static void free_desc(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + unsigned long flags; + + raw_spin_lock_irqsave(&desc->lock, flags); + desc_set_defaults(irq, desc, desc_node(desc)); + raw_spin_unlock_irqrestore(&desc->lock, flags); +} + +static inline int alloc_descs(unsigned int start, unsigned int cnt, int node) +{ + return start; +} #endif /* !CONFIG_SPARSE_IRQ */ +/* Dynamic interrupt handling */ + +/** + * irq_free_descs - free irq descriptors + * @from: Start of descriptor range + * @cnt: Number of consecutive irqs to free + */ +void irq_free_descs(unsigned int from, unsigned int cnt) +{ + unsigned long flags; + int i; + + if (from >= nr_irqs || (from + cnt) > nr_irqs) + return; + + for (i = 0; i < cnt; i++) + free_desc(from + i); + + raw_spin_lock_irqsave(&sparse_irq_lock, flags); + bitmap_clear(allocated_irqs, from, cnt); + raw_spin_unlock_irqrestore(&sparse_irq_lock, flags); +} + +/** + * irq_alloc_descs - allocate and initialize a range of irq descriptors + * @irq: Allocate for specific irq number if irq >= 0 + * @from: Start the search from this irq number + * @cnt: Number of consecutive irqs to allocate. + * @node: Preferred node on which the irq descriptor should be allocated + * + * Returns the first irq number or error code + */ +int __ref +irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node) +{ + unsigned long flags; + int start, ret; + + if (!cnt) + return -EINVAL; + + raw_spin_lock_irqsave(&sparse_irq_lock, flags); + + start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0); + ret = -EEXIST; + if (irq >=0 && start != irq) + goto err; + + ret = -ENOMEM; + if (start >= nr_irqs) + goto err; + + bitmap_set(allocated_irqs, start, cnt); + raw_spin_unlock_irqrestore(&sparse_irq_lock, flags); + return alloc_descs(start, cnt, node); + +err: + raw_spin_unlock_irqrestore(&sparse_irq_lock, flags); + return ret; +} + +/* Statistics access */ void clear_kstat_irqs(struct irq_desc *desc) { memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs))); |