2 * linux/kernel/irq/proc.c
4 * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
6 * This file contains the /proc/irq/ handling code.
10 #include <linux/proc_fs.h>
11 #include <linux/seq_file.h>
12 #include <linux/interrupt.h>
14 #include "internals.h"
16 static struct proc_dir_entry *root_irq_dir;
20 static int irq_affinity_proc_show(struct seq_file *m, void *v)
22 struct irq_desc *desc = irq_to_desc((long)m->private);
23 const struct cpumask *mask = desc->affinity;
25 #ifdef CONFIG_GENERIC_PENDING_IRQ
26 if (desc->status & IRQ_MOVE_PENDING)
27 mask = desc->pending_mask;
34 #ifndef is_affinity_mask_valid
35 #define is_affinity_mask_valid(val) 1
39 static ssize_t irq_affinity_proc_write(struct file *file,
40 const char __user *buffer, size_t count, loff_t *pos)
42 unsigned int irq = (int)(long)PDE(file->f_path.dentry->d_inode)->data;
43 cpumask_var_t new_value;
46 if (!irq_to_desc(irq)->chip->set_affinity || no_irq_affinity ||
47 irq_balancing_disabled(irq))
50 if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
53 err = cpumask_parse_user(buffer, count, new_value);
57 if (!is_affinity_mask_valid(new_value)) {
63 * Do not allow disabling IRQs completely - it's a too easy
64 * way to make the system unusable accidentally :-) At least
65 * one online CPU still has to be targeted.
67 if (!cpumask_intersects(new_value, cpu_online_mask)) {
68 /* Special case for empty set - allow the architecture
69 code to set default SMP affinity. */
70 err = irq_select_affinity_usr(irq) ? -EINVAL : count;
72 irq_set_affinity(irq, new_value);
77 free_cpumask_var(new_value);
81 static int irq_affinity_proc_open(struct inode *inode, struct file *file)
83 return single_open(file, irq_affinity_proc_show, PDE(inode)->data);
86 static const struct file_operations irq_affinity_proc_fops = {
87 .open = irq_affinity_proc_open,
90 .release = single_release,
91 .write = irq_affinity_proc_write,
94 static int default_affinity_show(struct seq_file *m, void *v)
96 seq_cpumask(m, irq_default_affinity);
101 static ssize_t default_affinity_write(struct file *file,
102 const char __user *buffer, size_t count, loff_t *ppos)
104 cpumask_var_t new_value;
107 if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
110 err = cpumask_parse_user(buffer, count, new_value);
114 if (!is_affinity_mask_valid(new_value)) {
120 * Do not allow disabling IRQs completely - it's a too easy
121 * way to make the system unusable accidentally :-) At least
122 * one online CPU still has to be targeted.
124 if (!cpumask_intersects(new_value, cpu_online_mask)) {
129 cpumask_copy(irq_default_affinity, new_value);
133 free_cpumask_var(new_value);
137 static int default_affinity_open(struct inode *inode, struct file *file)
139 return single_open(file, default_affinity_show, PDE(inode)->data);
142 static const struct file_operations default_affinity_proc_fops = {
143 .open = default_affinity_open,
146 .release = single_release,
147 .write = default_affinity_write,
150 static int irq_node_proc_show(struct seq_file *m, void *v)
152 struct irq_desc *desc = irq_to_desc((long) m->private);
154 seq_printf(m, "%d\n", desc->node);
158 static int irq_node_proc_open(struct inode *inode, struct file *file)
160 return single_open(file, irq_node_proc_show, PDE(inode)->data);
163 static const struct file_operations irq_node_proc_fops = {
164 .open = irq_node_proc_open,
167 .release = single_release,
171 static int irq_spurious_proc_show(struct seq_file *m, void *v)
173 struct irq_desc *desc = irq_to_desc((long) m->private);
175 seq_printf(m, "count %u\n" "unhandled %u\n" "last_unhandled %u ms\n",
176 desc->irq_count, desc->irqs_unhandled,
177 jiffies_to_msecs(desc->last_unhandled));
181 static int irq_spurious_proc_open(struct inode *inode, struct file *file)
183 return single_open(file, irq_spurious_proc_show, NULL);
186 static const struct file_operations irq_spurious_proc_fops = {
187 .open = irq_spurious_proc_open,
190 .release = single_release,
193 #define MAX_NAMELEN 128
195 static int name_unique(unsigned int irq, struct irqaction *new_action)
197 struct irq_desc *desc = irq_to_desc(irq);
198 struct irqaction *action;
202 raw_spin_lock_irqsave(&desc->lock, flags);
203 for (action = desc->action ; action; action = action->next) {
204 if ((action != new_action) && action->name &&
205 !strcmp(new_action->name, action->name)) {
210 raw_spin_unlock_irqrestore(&desc->lock, flags);
214 void register_handler_proc(unsigned int irq, struct irqaction *action)
216 char name [MAX_NAMELEN];
217 struct irq_desc *desc = irq_to_desc(irq);
219 if (!desc->dir || action->dir || !action->name ||
220 !name_unique(irq, action))
223 memset(name, 0, MAX_NAMELEN);
224 snprintf(name, MAX_NAMELEN, "%s", action->name);
226 /* create /proc/irq/1234/handler/ */
227 action->dir = proc_mkdir(name, desc->dir);
232 #define MAX_NAMELEN 10
234 void register_irq_proc(unsigned int irq, struct irq_desc *desc)
236 char name [MAX_NAMELEN];
238 if (!root_irq_dir || (desc->chip == &no_irq_chip) || desc->dir)
241 memset(name, 0, MAX_NAMELEN);
242 sprintf(name, "%d", irq);
244 /* create /proc/irq/1234 */
245 desc->dir = proc_mkdir(name, root_irq_dir);
250 /* create /proc/irq/<irq>/smp_affinity */
251 proc_create_data("smp_affinity", 0600, desc->dir,
252 &irq_affinity_proc_fops, (void *)(long)irq);
254 proc_create_data("node", 0444, desc->dir,
255 &irq_node_proc_fops, (void *)(long)irq);
258 proc_create_data("spurious", 0444, desc->dir,
259 &irq_spurious_proc_fops, (void *)(long)irq);
264 void unregister_handler_proc(unsigned int irq, struct irqaction *action)
267 struct irq_desc *desc = irq_to_desc(irq);
269 remove_proc_entry(action->dir->name, desc->dir);
273 static void register_default_affinity_proc(void)
276 proc_create("irq/default_smp_affinity", 0600, NULL,
277 &default_affinity_proc_fops);
281 void init_irq_proc(void)
284 struct irq_desc *desc;
286 /* create /proc/irq */
287 root_irq_dir = proc_mkdir("irq", NULL);
291 register_default_affinity_proc();
294 * Create entries for all existing IRQs.
296 for_each_irq_desc(irq, desc) {
300 register_irq_proc(irq, desc);