From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- kernel/irq/proc.c | 501 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 501 insertions(+) create mode 100644 kernel/irq/proc.c (limited to 'kernel/irq/proc.c') diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c new file mode 100644 index 000000000..df2f4642d --- /dev/null +++ b/kernel/irq/proc.c @@ -0,0 +1,501 @@ +/* + * linux/kernel/irq/proc.c + * + * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar + * + * This file contains the /proc/irq/ handling code. + */ + +#include +#include +#include +#include +#include +#include + +#include "internals.h" + +/* + * Access rules: + * + * procfs protects read/write of /proc/irq/N/ files against a + * concurrent free of the interrupt descriptor. remove_proc_entry() + * immediately prevents new read/writes to happen and waits for + * already running read/write functions to complete. + * + * We remove the proc entries first and then delete the interrupt + * descriptor from the radix tree and free it. So it is guaranteed + * that irq_to_desc(N) is valid as long as the read/writes are + * permitted by procfs. + * + * The read from /proc/interrupts is a different problem because there + * is no protection. So the lookup and the access to irqdesc + * information must be protected by sparse_irq_lock. + */ +static struct proc_dir_entry *root_irq_dir; + +#ifdef CONFIG_SMP + +static int show_irq_affinity(int type, struct seq_file *m, void *v) +{ + struct irq_desc *desc = irq_to_desc((long)m->private); + const struct cpumask *mask = desc->irq_data.affinity; + +#ifdef CONFIG_GENERIC_PENDING_IRQ + if (irqd_is_setaffinity_pending(&desc->irq_data)) + mask = desc->pending_mask; +#endif + if (type) + seq_printf(m, "%*pbl\n", cpumask_pr_args(mask)); + else + seq_printf(m, "%*pb\n", cpumask_pr_args(mask)); + return 0; +} + +static int irq_affinity_hint_proc_show(struct seq_file *m, void *v) +{ + struct irq_desc *desc = irq_to_desc((long)m->private); + unsigned long flags; + cpumask_var_t mask; + + if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) + return -ENOMEM; + + raw_spin_lock_irqsave(&desc->lock, flags); + if (desc->affinity_hint) + cpumask_copy(mask, desc->affinity_hint); + raw_spin_unlock_irqrestore(&desc->lock, flags); + + seq_printf(m, "%*pb\n", cpumask_pr_args(mask)); + free_cpumask_var(mask); + + return 0; +} + +#ifndef is_affinity_mask_valid +#define is_affinity_mask_valid(val) 1 +#endif + +int no_irq_affinity; +static int irq_affinity_proc_show(struct seq_file *m, void *v) +{ + return show_irq_affinity(0, m, v); +} + +static int irq_affinity_list_proc_show(struct seq_file *m, void *v) +{ + return show_irq_affinity(1, m, v); +} + + +static ssize_t write_irq_affinity(int type, struct file *file, + const char __user *buffer, size_t count, loff_t *pos) +{ + unsigned int irq = (int)(long)PDE_DATA(file_inode(file)); + cpumask_var_t new_value; + int err; + + if (!irq_can_set_affinity(irq) || no_irq_affinity) + return -EIO; + + if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) + return -ENOMEM; + + if (type) + err = cpumask_parselist_user(buffer, count, new_value); + else + err = cpumask_parse_user(buffer, count, new_value); + if (err) + goto free_cpumask; + + if (!is_affinity_mask_valid(new_value)) { + err = -EINVAL; + goto free_cpumask; + } + + /* + * Do not allow disabling IRQs completely - it's a too easy + * way to make the system unusable accidentally :-) At least + * one online CPU still has to be targeted. + */ + if (!cpumask_intersects(new_value, cpu_online_mask)) { + /* Special case for empty set - allow the architecture + code to set default SMP affinity. */ + err = irq_select_affinity_usr(irq, new_value) ? -EINVAL : count; + } else { + irq_set_affinity(irq, new_value); + err = count; + } + +free_cpumask: + free_cpumask_var(new_value); + return err; +} + +static ssize_t irq_affinity_proc_write(struct file *file, + const char __user *buffer, size_t count, loff_t *pos) +{ + return write_irq_affinity(0, file, buffer, count, pos); +} + +static ssize_t irq_affinity_list_proc_write(struct file *file, + const char __user *buffer, size_t count, loff_t *pos) +{ + return write_irq_affinity(1, file, buffer, count, pos); +} + +static int irq_affinity_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_affinity_proc_show, PDE_DATA(inode)); +} + +static int irq_affinity_list_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_affinity_list_proc_show, PDE_DATA(inode)); +} + +static int irq_affinity_hint_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_affinity_hint_proc_show, PDE_DATA(inode)); +} + +static const struct file_operations irq_affinity_proc_fops = { + .open = irq_affinity_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = irq_affinity_proc_write, +}; + +static const struct file_operations irq_affinity_hint_proc_fops = { + .open = irq_affinity_hint_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations irq_affinity_list_proc_fops = { + .open = irq_affinity_list_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = irq_affinity_list_proc_write, +}; + +static int default_affinity_show(struct seq_file *m, void *v) +{ + seq_printf(m, "%*pb\n", cpumask_pr_args(irq_default_affinity)); + return 0; +} + +static ssize_t default_affinity_write(struct file *file, + const char __user *buffer, size_t count, loff_t *ppos) +{ + cpumask_var_t new_value; + int err; + + if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) + return -ENOMEM; + + err = cpumask_parse_user(buffer, count, new_value); + if (err) + goto out; + + if (!is_affinity_mask_valid(new_value)) { + err = -EINVAL; + goto out; + } + + /* + * Do not allow disabling IRQs completely - it's a too easy + * way to make the system unusable accidentally :-) At least + * one online CPU still has to be targeted. + */ + if (!cpumask_intersects(new_value, cpu_online_mask)) { + err = -EINVAL; + goto out; + } + + cpumask_copy(irq_default_affinity, new_value); + err = count; + +out: + free_cpumask_var(new_value); + return err; +} + +static int default_affinity_open(struct inode *inode, struct file *file) +{ + return single_open(file, default_affinity_show, PDE_DATA(inode)); +} + +static const struct file_operations default_affinity_proc_fops = { + .open = default_affinity_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = default_affinity_write, +}; + +static int irq_node_proc_show(struct seq_file *m, void *v) +{ + struct irq_desc *desc = irq_to_desc((long) m->private); + + seq_printf(m, "%d\n", desc->irq_data.node); + return 0; +} + +static int irq_node_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_node_proc_show, PDE_DATA(inode)); +} + +static const struct file_operations irq_node_proc_fops = { + .open = irq_node_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; +#endif + +static int irq_spurious_proc_show(struct seq_file *m, void *v) +{ + struct irq_desc *desc = irq_to_desc((long) m->private); + + seq_printf(m, "count %u\n" "unhandled %u\n" "last_unhandled %u ms\n", + desc->irq_count, desc->irqs_unhandled, + jiffies_to_msecs(desc->last_unhandled)); + return 0; +} + +static int irq_spurious_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_spurious_proc_show, PDE_DATA(inode)); +} + +static const struct file_operations irq_spurious_proc_fops = { + .open = irq_spurious_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +#define MAX_NAMELEN 128 + +static int name_unique(unsigned int irq, struct irqaction *new_action) +{ + struct irq_desc *desc = irq_to_desc(irq); + struct irqaction *action; + unsigned long flags; + int ret = 1; + + raw_spin_lock_irqsave(&desc->lock, flags); + for (action = desc->action ; action; action = action->next) { + if ((action != new_action) && action->name && + !strcmp(new_action->name, action->name)) { + ret = 0; + break; + } + } + raw_spin_unlock_irqrestore(&desc->lock, flags); + return ret; +} + +void register_handler_proc(unsigned int irq, struct irqaction *action) +{ + char name [MAX_NAMELEN]; + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc->dir || action->dir || !action->name || + !name_unique(irq, action)) + return; + + memset(name, 0, MAX_NAMELEN); + snprintf(name, MAX_NAMELEN, "%s", action->name); + + /* create /proc/irq/1234/handler/ */ + action->dir = proc_mkdir(name, desc->dir); +} + +#undef MAX_NAMELEN + +#define MAX_NAMELEN 10 + +void register_irq_proc(unsigned int irq, struct irq_desc *desc) +{ + char name [MAX_NAMELEN]; + + if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip) || desc->dir) + return; + + memset(name, 0, MAX_NAMELEN); + sprintf(name, "%d", irq); + + /* create /proc/irq/1234 */ + desc->dir = proc_mkdir(name, root_irq_dir); + if (!desc->dir) + return; + +#ifdef CONFIG_SMP + /* create /proc/irq//smp_affinity */ + proc_create_data("smp_affinity", 0644, desc->dir, + &irq_affinity_proc_fops, (void *)(long)irq); + + /* create /proc/irq//affinity_hint */ + proc_create_data("affinity_hint", 0444, desc->dir, + &irq_affinity_hint_proc_fops, (void *)(long)irq); + + /* create /proc/irq//smp_affinity_list */ + proc_create_data("smp_affinity_list", 0644, desc->dir, + &irq_affinity_list_proc_fops, (void *)(long)irq); + + proc_create_data("node", 0444, desc->dir, + &irq_node_proc_fops, (void *)(long)irq); +#endif + + proc_create_data("spurious", 0444, desc->dir, + &irq_spurious_proc_fops, (void *)(long)irq); +} + +void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) +{ + char name [MAX_NAMELEN]; + + if (!root_irq_dir || !desc->dir) + return; +#ifdef CONFIG_SMP + remove_proc_entry("smp_affinity", desc->dir); + remove_proc_entry("affinity_hint", desc->dir); + remove_proc_entry("smp_affinity_list", desc->dir); + remove_proc_entry("node", desc->dir); +#endif + remove_proc_entry("spurious", desc->dir); + + memset(name, 0, MAX_NAMELEN); + sprintf(name, "%u", irq); + remove_proc_entry(name, root_irq_dir); +} + +#undef MAX_NAMELEN + +void unregister_handler_proc(unsigned int irq, struct irqaction *action) +{ + proc_remove(action->dir); +} + +static void register_default_affinity_proc(void) +{ +#ifdef CONFIG_SMP + proc_create("irq/default_smp_affinity", 0644, NULL, + &default_affinity_proc_fops); +#endif +} + +void init_irq_proc(void) +{ + unsigned int irq; + struct irq_desc *desc; + + /* create /proc/irq */ + root_irq_dir = proc_mkdir("irq", NULL); + if (!root_irq_dir) + return; + + register_default_affinity_proc(); + + /* + * Create entries for all existing IRQs. + */ + for_each_irq_desc(irq, desc) { + if (!desc) + continue; + + register_irq_proc(irq, desc); + } +} + +#ifdef CONFIG_GENERIC_IRQ_SHOW + +int __weak arch_show_interrupts(struct seq_file *p, int prec) +{ + return 0; +} + +#ifndef ACTUAL_NR_IRQS +# define ACTUAL_NR_IRQS nr_irqs +#endif + +int show_interrupts(struct seq_file *p, void *v) +{ + static int prec; + + unsigned long flags, any_count = 0; + int i = *(loff_t *) v, j; + struct irqaction *action; + struct irq_desc *desc; + + if (i > ACTUAL_NR_IRQS) + return 0; + + if (i == ACTUAL_NR_IRQS) + return arch_show_interrupts(p, prec); + + /* print header and calculate the width of the first column */ + if (i == 0) { + for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec) + j *= 10; + + seq_printf(p, "%*s", prec + 8, ""); + for_each_online_cpu(j) + seq_printf(p, "CPU%-8d", j); + seq_putc(p, '\n'); + } + + irq_lock_sparse(); + desc = irq_to_desc(i); + if (!desc) + goto outsparse; + + raw_spin_lock_irqsave(&desc->lock, flags); + for_each_online_cpu(j) + any_count |= kstat_irqs_cpu(i, j); + action = desc->action; + if (!action && !any_count) + goto out; + + seq_printf(p, "%*d: ", prec, i); + for_each_online_cpu(j) + seq_printf(p, "%10u ", kstat_irqs_cpu(i, j)); + + if (desc->irq_data.chip) { + if (desc->irq_data.chip->irq_print_chip) + desc->irq_data.chip->irq_print_chip(&desc->irq_data, p); + else if (desc->irq_data.chip->name) + seq_printf(p, " %8s", desc->irq_data.chip->name); + else + seq_printf(p, " %8s", "-"); + } else { + seq_printf(p, " %8s", "None"); + } + if (desc->irq_data.domain) + seq_printf(p, " %*d", prec, (int) desc->irq_data.hwirq); +#ifdef CONFIG_GENERIC_IRQ_SHOW_LEVEL + seq_printf(p, " %-8s", irqd_is_level_type(&desc->irq_data) ? "Level" : "Edge"); +#endif + if (desc->name) + seq_printf(p, "-%-8s", desc->name); + + if (action) { + seq_printf(p, " %s", action->name); + while ((action = action->next) != NULL) + seq_printf(p, ", %s", action->name); + } + + seq_putc(p, '\n'); +out: + raw_spin_unlock_irqrestore(&desc->lock, flags); +outsparse: + irq_unlock_sparse(); + return 0; +} +#endif -- cgit v1.2.3