linux/kernel/irq/proc.c
Linus Torvalds 670310dfba Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq core updates from Thomas Gleixner:
 "A rather large update for the interrupt core code and the irq chip drivers:

   - Add a new bitmap matrix allocator and supporting changes, which is
     used to replace the x86 vector allocator which comes with separate
     pull request. This allows to replace the convoluted nested loop
     allocation function in x86 with a facility which supports the
     recently added property of managed interrupts proper and allows to
     switch to a best effort vector reservation scheme, which addresses
     problems with vector exhaustion.

   - A large update to the ARM GIC-V3-ITS driver adding support for
     range selectors.

   - New interrupt controllers:
       - Meson and Meson8 GPIO
       - BCM7271 L2
       - Socionext EXIU

     If you expected that this will stop at some point, I have to
     disappoint you. There are new ones posted already. Sigh!

   - STM32 interrupt controller support for new platforms.

   - A pile of fixes, cleanups and updates to the MIPS GIC driver

   - The usual small fixes, cleanups and updates all over the place.
     Most visible one is to move the irq chip drivers Kconfig switches
     into a separate Kconfig menu"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
  genirq: Fix type of shifting literal 1 in __setup_irq()
  irqdomain: Drop pointless NULL check in virq_debug_show_one
  genirq/proc: Return proper error code when irq_set_affinity() fails
  irq/work: Use llist_for_each_entry_safe
  irqchip: mips-gic: Print warning if inherited GIC base is used
  irqchip/mips-gic: Add pr_fmt and reword pr_* messages
  irqchip/stm32: Move the wakeup on interrupt mask
  irqchip/stm32: Fix initial values
  irqchip/stm32: Add stm32h7 support
  dt-bindings/interrupt-controllers: Add compatible string for stm32h7
  irqchip/stm32: Add multi-bank management
  irqchip/stm32: Select GENERIC_IRQ_CHIP
  irqchip/exiu: Add support for Socionext Synquacer EXIU controller
  dt-bindings: Add description of Socionext EXIU interrupt controller
  irqchip/gic-v3-its: Fix VPE activate callback return value
  irqchip: mips-gic: Make IPI bitmaps static
  irqchip: mips-gic: Share register writes in gic_set_type()
  irqchip: mips-gic: Remove gic_vpes variable
  irqchip: mips-gic: Use num_possible_cpus() to reserve IPIs
  irqchip: mips-gic: Configure EIC when CPUs come online
  ...
2017-11-13 17:33:11 -08:00

592 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/kernel/irq/proc.c
*
* Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
*
* This file contains the /proc/irq/ handling code.
*/
#include <linux/irq.h>
#include <linux/gfp.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/mutex.h>
#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
enum {
AFFINITY,
AFFINITY_LIST,
EFFECTIVE,
EFFECTIVE_LIST,
};
static int show_irq_affinity(int type, struct seq_file *m)
{
struct irq_desc *desc = irq_to_desc((long)m->private);
const struct cpumask *mask;
switch (type) {
case AFFINITY:
case AFFINITY_LIST:
mask = desc->irq_common_data.affinity;
#ifdef CONFIG_GENERIC_PENDING_IRQ
if (irqd_is_setaffinity_pending(&desc->irq_data))
mask = desc->pending_mask;
#endif
break;
case EFFECTIVE:
case EFFECTIVE_LIST:
#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
mask = irq_data_get_effective_affinity_mask(&desc->irq_data);
break;
#endif
default:
return -EINVAL;
}
switch (type) {
case AFFINITY_LIST:
case EFFECTIVE_LIST:
seq_printf(m, "%*pbl\n", cpumask_pr_args(mask));
break;
case AFFINITY:
case EFFECTIVE:
seq_printf(m, "%*pb\n", cpumask_pr_args(mask));
break;
}
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(AFFINITY, m);
}
static int irq_affinity_list_proc_show(struct seq_file *m, void *v)
{
return show_irq_affinity(AFFINITY_LIST, m);
}
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_usr(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) ? -EINVAL : count;
} else {
err = irq_set_affinity(irq, new_value);
if (!err)
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,
};
#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
static int irq_effective_aff_proc_show(struct seq_file *m, void *v)
{
return show_irq_affinity(EFFECTIVE, m);
}
static int irq_effective_aff_list_proc_show(struct seq_file *m, void *v)
{
return show_irq_affinity(EFFECTIVE_LIST, m);
}
static int irq_effective_aff_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, irq_effective_aff_proc_show, PDE_DATA(inode));
}
static int irq_effective_aff_list_proc_open(struct inode *inode,
struct file *file)
{
return single_open(file, irq_effective_aff_list_proc_show,
PDE_DATA(inode));
}
static const struct file_operations irq_effective_aff_proc_fops = {
.open = irq_effective_aff_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations irq_effective_aff_list_proc_fops = {
.open = irq_effective_aff_list_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#endif
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", irq_desc_get_node(desc));
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_each_action_of_desc(desc, action) {
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;
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)
{
static DEFINE_MUTEX(register_lock);
void __maybe_unused *irqp = (void *)(unsigned long) irq;
char name [MAX_NAMELEN];
if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip))
return;
/*
* irq directories are registered only when a handler is
* added, not when the descriptor is created, so multiple
* tasks might try to register at the same time.
*/
mutex_lock(&register_lock);
if (desc->dir)
goto out_unlock;
sprintf(name, "%d", irq);
/* create /proc/irq/1234 */
desc->dir = proc_mkdir(name, root_irq_dir);
if (!desc->dir)
goto out_unlock;
#ifdef CONFIG_SMP
/* create /proc/irq/<irq>/smp_affinity */
proc_create_data("smp_affinity", 0644, desc->dir,
&irq_affinity_proc_fops, irqp);
/* create /proc/irq/<irq>/affinity_hint */
proc_create_data("affinity_hint", 0444, desc->dir,
&irq_affinity_hint_proc_fops, irqp);
/* create /proc/irq/<irq>/smp_affinity_list */
proc_create_data("smp_affinity_list", 0644, desc->dir,
&irq_affinity_list_proc_fops, irqp);
proc_create_data("node", 0444, desc->dir,
&irq_node_proc_fops, irqp);
# ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
proc_create_data("effective_affinity", 0444, desc->dir,
&irq_effective_aff_proc_fops, irqp);
proc_create_data("effective_affinity_list", 0444, desc->dir,
&irq_effective_aff_list_proc_fops, irqp);
# endif
#endif
proc_create_data("spurious", 0444, desc->dir,
&irq_spurious_proc_fops, (void *)(long)irq);
out_unlock:
mutex_unlock(&register_lock);
}
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);
# ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
remove_proc_entry("effective_affinity", desc->dir);
remove_proc_entry("effective_affinity_list", desc->dir);
# endif
#endif
remove_proc_entry("spurious", desc->dir);
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)
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 || irq_desc_is_chained(desc)) && !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);
else
seq_printf(p, " %*s", prec, "");
#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