diff options
Diffstat (limited to 'kernel/irq')
-rw-r--r-- | kernel/irq/irqdesc.c | 193 |
1 files changed, 191 insertions, 2 deletions
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index a623b44f2d4b..93b51727abaa 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -15,6 +15,7 @@ #include <linux/radix-tree.h> #include <linux/bitmap.h> #include <linux/irqdomain.h> +#include <linux/sysfs.h> #include "internals.h" @@ -123,6 +124,181 @@ static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS); #ifdef CONFIG_SPARSE_IRQ +static void irq_kobj_release(struct kobject *kobj); + +#ifdef CONFIG_SYSFS +static struct kobject *irq_kobj_base; + +#define IRQ_ATTR_RO(_name) \ +static struct kobj_attribute _name##_attr = __ATTR_RO(_name) + +static ssize_t per_cpu_count_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); + int cpu, irq = desc->irq_data.irq; + ssize_t ret = 0; + char *p = ""; + + for_each_possible_cpu(cpu) { + unsigned int c = kstat_irqs_cpu(irq, cpu); + + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c); + p = ","; + } + + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n"); + return ret; +} +IRQ_ATTR_RO(per_cpu_count); + +static ssize_t chip_name_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); + ssize_t ret = 0; + + raw_spin_lock_irq(&desc->lock); + if (desc->irq_data.chip && desc->irq_data.chip->name) { + ret = scnprintf(buf, PAGE_SIZE, "%s\n", + desc->irq_data.chip->name); + } + raw_spin_unlock_irq(&desc->lock); + + return ret; +} +IRQ_ATTR_RO(chip_name); + +static ssize_t hwirq_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); + ssize_t ret = 0; + + raw_spin_lock_irq(&desc->lock); + if (desc->irq_data.domain) + ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq); + raw_spin_unlock_irq(&desc->lock); + + return ret; +} +IRQ_ATTR_RO(hwirq); + +static ssize_t type_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); + ssize_t ret = 0; + + raw_spin_lock_irq(&desc->lock); + ret = sprintf(buf, "%s\n", + irqd_is_level_type(&desc->irq_data) ? "level" : "edge"); + raw_spin_unlock_irq(&desc->lock); + + return ret; + +} +IRQ_ATTR_RO(type); + +static ssize_t name_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); + ssize_t ret = 0; + + raw_spin_lock_irq(&desc->lock); + if (desc->name) + ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name); + raw_spin_unlock_irq(&desc->lock); + + return ret; +} +IRQ_ATTR_RO(name); + +static ssize_t actions_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); + struct irqaction *action; + ssize_t ret = 0; + char *p = ""; + + raw_spin_lock_irq(&desc->lock); + for (action = desc->action; action != NULL; action = action->next) { + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s", + p, action->name); + p = ","; + } + raw_spin_unlock_irq(&desc->lock); + + if (ret) + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n"); + + return ret; +} +IRQ_ATTR_RO(actions); + +static struct attribute *irq_attrs[] = { + &per_cpu_count_attr.attr, + &chip_name_attr.attr, + &hwirq_attr.attr, + &type_attr.attr, + &name_attr.attr, + &actions_attr.attr, + NULL +}; + +static struct kobj_type irq_kobj_type = { + .release = irq_kobj_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_attrs = irq_attrs, +}; + +static void irq_sysfs_add(int irq, struct irq_desc *desc) +{ + if (irq_kobj_base) { + /* + * Continue even in case of failure as this is nothing + * crucial. + */ + if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq)) + pr_warn("Failed to add kobject for irq %d\n", irq); + } +} + +static int __init irq_sysfs_init(void) +{ + struct irq_desc *desc; + int irq; + + /* Prevent concurrent irq alloc/free */ + irq_lock_sparse(); + + irq_kobj_base = kobject_create_and_add("irq", kernel_kobj); + if (!irq_kobj_base) { + irq_unlock_sparse(); + return -ENOMEM; + } + + /* Add the already allocated interrupts */ + for_each_irq_desc(irq, desc) + irq_sysfs_add(irq, desc); + irq_unlock_sparse(); + + return 0; +} +postcore_initcall(irq_sysfs_init); + +#else /* !CONFIG_SYSFS */ + +static struct kobj_type irq_kobj_type = { + .release = irq_kobj_release, +}; + +static void irq_sysfs_add(int irq, struct irq_desc *desc) {} + +#endif /* CONFIG_SYSFS */ + static RADIX_TREE(irq_desc_tree, GFP_KERNEL); static void irq_insert_desc(unsigned int irq, struct irq_desc *desc) @@ -187,6 +363,7 @@ static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags, desc_set_defaults(irq, desc, node, affinity, owner); irqd_set(&desc->irq_data, flags); + kobject_init(&desc->kobj, &irq_kobj_type); return desc; @@ -197,15 +374,22 @@ err_desc: return NULL; } -static void delayed_free_desc(struct rcu_head *rhp) +static void irq_kobj_release(struct kobject *kobj) { - struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu); + struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); free_masks(desc); free_percpu(desc->kstat_irqs); kfree(desc); } +static void delayed_free_desc(struct rcu_head *rhp) +{ + struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu); + + kobject_put(&desc->kobj); +} + static void free_desc(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); @@ -217,8 +401,12 @@ static void free_desc(unsigned int irq) * kstat_irq_usr(). Once we deleted the descriptor from the * sparse tree we can free it. Access in proc will fail to * lookup the descriptor. + * + * The sysfs entry must be serialized against a concurrent + * irq_sysfs_init() as well. */ mutex_lock(&sparse_irq_lock); + kobject_del(&desc->kobj); delete_irq_desc(irq); mutex_unlock(&sparse_irq_lock); @@ -261,6 +449,7 @@ static int alloc_descs(unsigned int start, unsigned int cnt, int node, goto err; mutex_lock(&sparse_irq_lock); irq_insert_desc(start + i, desc); + irq_sysfs_add(start + i, desc); mutex_unlock(&sparse_irq_lock); } return start; |