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![Thomas Gleixner](/assets/img/avatar_default.png)
Convert locks which cannot be sleeping locks in preempt-rt to raw_spinlocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
280 lines
6.2 KiB
C
280 lines
6.2 KiB
C
/*
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* linux/kernel/irq/proc.c
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*
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* Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
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*
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* This file contains the /proc/irq/ handling code.
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*/
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#include <linux/irq.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/interrupt.h>
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#include "internals.h"
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static struct proc_dir_entry *root_irq_dir;
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#ifdef CONFIG_SMP
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static int irq_affinity_proc_show(struct seq_file *m, void *v)
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{
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struct irq_desc *desc = irq_to_desc((long)m->private);
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const struct cpumask *mask = desc->affinity;
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#ifdef CONFIG_GENERIC_PENDING_IRQ
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if (desc->status & IRQ_MOVE_PENDING)
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mask = desc->pending_mask;
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#endif
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seq_cpumask(m, mask);
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seq_putc(m, '\n');
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return 0;
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}
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#ifndef is_affinity_mask_valid
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#define is_affinity_mask_valid(val) 1
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#endif
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int no_irq_affinity;
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static ssize_t irq_affinity_proc_write(struct file *file,
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const char __user *buffer, size_t count, loff_t *pos)
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{
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unsigned int irq = (int)(long)PDE(file->f_path.dentry->d_inode)->data;
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cpumask_var_t new_value;
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int err;
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if (!irq_to_desc(irq)->chip->set_affinity || no_irq_affinity ||
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irq_balancing_disabled(irq))
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return -EIO;
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if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
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return -ENOMEM;
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err = cpumask_parse_user(buffer, count, new_value);
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if (err)
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goto free_cpumask;
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if (!is_affinity_mask_valid(new_value)) {
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err = -EINVAL;
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goto free_cpumask;
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}
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/*
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* Do not allow disabling IRQs completely - it's a too easy
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* way to make the system unusable accidentally :-) At least
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* one online CPU still has to be targeted.
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*/
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if (!cpumask_intersects(new_value, cpu_online_mask)) {
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/* Special case for empty set - allow the architecture
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code to set default SMP affinity. */
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err = irq_select_affinity_usr(irq) ? -EINVAL : count;
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} else {
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irq_set_affinity(irq, new_value);
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err = count;
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}
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free_cpumask:
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free_cpumask_var(new_value);
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return err;
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}
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static int irq_affinity_proc_open(struct inode *inode, struct file *file)
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{
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return single_open(file, irq_affinity_proc_show, PDE(inode)->data);
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}
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static const struct file_operations irq_affinity_proc_fops = {
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.open = irq_affinity_proc_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = single_release,
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.write = irq_affinity_proc_write,
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};
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static int default_affinity_show(struct seq_file *m, void *v)
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{
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seq_cpumask(m, irq_default_affinity);
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seq_putc(m, '\n');
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return 0;
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}
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static ssize_t default_affinity_write(struct file *file,
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const char __user *buffer, size_t count, loff_t *ppos)
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{
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cpumask_var_t new_value;
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int err;
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if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
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return -ENOMEM;
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err = cpumask_parse_user(buffer, count, new_value);
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if (err)
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goto out;
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if (!is_affinity_mask_valid(new_value)) {
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err = -EINVAL;
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goto out;
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}
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/*
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* Do not allow disabling IRQs completely - it's a too easy
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* way to make the system unusable accidentally :-) At least
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* one online CPU still has to be targeted.
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*/
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if (!cpumask_intersects(new_value, cpu_online_mask)) {
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err = -EINVAL;
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goto out;
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}
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cpumask_copy(irq_default_affinity, new_value);
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err = count;
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out:
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free_cpumask_var(new_value);
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return err;
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}
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static int default_affinity_open(struct inode *inode, struct file *file)
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{
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return single_open(file, default_affinity_show, PDE(inode)->data);
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}
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static const struct file_operations default_affinity_proc_fops = {
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.open = default_affinity_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = single_release,
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.write = default_affinity_write,
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};
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#endif
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static int irq_spurious_proc_show(struct seq_file *m, void *v)
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{
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struct irq_desc *desc = irq_to_desc((long) m->private);
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seq_printf(m, "count %u\n" "unhandled %u\n" "last_unhandled %u ms\n",
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desc->irq_count, desc->irqs_unhandled,
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jiffies_to_msecs(desc->last_unhandled));
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return 0;
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}
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static int irq_spurious_proc_open(struct inode *inode, struct file *file)
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{
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return single_open(file, irq_spurious_proc_show, NULL);
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}
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static const struct file_operations irq_spurious_proc_fops = {
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.open = irq_spurious_proc_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = single_release,
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};
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#define MAX_NAMELEN 128
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static int name_unique(unsigned int irq, struct irqaction *new_action)
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{
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struct irq_desc *desc = irq_to_desc(irq);
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struct irqaction *action;
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unsigned long flags;
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int ret = 1;
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raw_spin_lock_irqsave(&desc->lock, flags);
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for (action = desc->action ; action; action = action->next) {
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if ((action != new_action) && action->name &&
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!strcmp(new_action->name, action->name)) {
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ret = 0;
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break;
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}
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}
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raw_spin_unlock_irqrestore(&desc->lock, flags);
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return ret;
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}
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void register_handler_proc(unsigned int irq, struct irqaction *action)
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{
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char name [MAX_NAMELEN];
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struct irq_desc *desc = irq_to_desc(irq);
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if (!desc->dir || action->dir || !action->name ||
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!name_unique(irq, action))
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return;
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memset(name, 0, MAX_NAMELEN);
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snprintf(name, MAX_NAMELEN, "%s", action->name);
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/* create /proc/irq/1234/handler/ */
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action->dir = proc_mkdir(name, desc->dir);
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}
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#undef MAX_NAMELEN
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#define MAX_NAMELEN 10
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void register_irq_proc(unsigned int irq, struct irq_desc *desc)
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{
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char name [MAX_NAMELEN];
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if (!root_irq_dir || (desc->chip == &no_irq_chip) || desc->dir)
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return;
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memset(name, 0, MAX_NAMELEN);
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sprintf(name, "%d", irq);
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/* create /proc/irq/1234 */
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desc->dir = proc_mkdir(name, root_irq_dir);
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if (!desc->dir)
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return;
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#ifdef CONFIG_SMP
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/* create /proc/irq/<irq>/smp_affinity */
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proc_create_data("smp_affinity", 0600, desc->dir,
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&irq_affinity_proc_fops, (void *)(long)irq);
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#endif
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proc_create_data("spurious", 0444, desc->dir,
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&irq_spurious_proc_fops, (void *)(long)irq);
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}
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#undef MAX_NAMELEN
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void unregister_handler_proc(unsigned int irq, struct irqaction *action)
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{
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if (action->dir) {
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struct irq_desc *desc = irq_to_desc(irq);
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remove_proc_entry(action->dir->name, desc->dir);
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}
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}
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static void register_default_affinity_proc(void)
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{
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#ifdef CONFIG_SMP
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proc_create("irq/default_smp_affinity", 0600, NULL,
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&default_affinity_proc_fops);
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#endif
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}
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void init_irq_proc(void)
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{
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unsigned int irq;
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struct irq_desc *desc;
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/* create /proc/irq */
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root_irq_dir = proc_mkdir("irq", NULL);
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if (!root_irq_dir)
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return;
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register_default_affinity_proc();
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/*
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* Create entries for all existing IRQs.
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*/
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for_each_irq_desc(irq, desc) {
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if (!desc)
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continue;
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register_irq_proc(irq, desc);
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}
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}
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