linux/kernel/irq/debugfs.c

216 lines
5.7 KiB
C
Raw Normal View History

genirq/debugfs: Add proper debugfs interface Debugging (hierarchical) interupt domains is tedious as there is no information about the hierarchy and no information about states of interrupts in the various domain levels. Add a debugfs directory 'irq' and subdirectories 'domains' and 'irqs'. The domains directory contains the domain files. The content is information about the domain. If the domain is part of a hierarchy then the parent domains are printed as well. # ls /sys/kernel/debug/irq/domains/ default INTEL-IR-2 INTEL-IR-MSI-2 IO-APIC-IR-2 PCI-MSI DMAR-MSI INTEL-IR-3 INTEL-IR-MSI-3 IO-APIC-IR-3 unknown-1 INTEL-IR-0 INTEL-IR-MSI-0 IO-APIC-IR-0 IO-APIC-IR-4 VECTOR INTEL-IR-1 INTEL-IR-MSI-1 IO-APIC-IR-1 PCI-HT # cat /sys/kernel/debug/irq/domains/VECTOR name: VECTOR size: 0 mapped: 216 flags: 0x00000041 # cat /sys/kernel/debug/irq/domains/IO-APIC-IR-0 name: IO-APIC-IR-0 size: 24 mapped: 19 flags: 0x00000041 parent: INTEL-IR-3 name: INTEL-IR-3 size: 65536 mapped: 167 flags: 0x00000041 parent: VECTOR name: VECTOR size: 0 mapped: 216 flags: 0x00000041 Unfortunately there is no per cpu information about the VECTOR domain (yet). The irqs directory contains detailed information about mapped interrupts. # cat /sys/kernel/debug/irq/irqs/3 handler: handle_edge_irq status: 0x00004000 istate: 0x00000000 ddepth: 1 wdepth: 0 dstate: 0x01018000 IRQD_IRQ_DISABLED IRQD_SINGLE_TARGET IRQD_MOVE_PCNTXT node: 0 affinity: 0-143 effectiv: 0 pending: domain: IO-APIC-IR-0 hwirq: 0x3 chip: IR-IO-APIC flags: 0x10 IRQCHIP_SKIP_SET_WAKE parent: domain: INTEL-IR-3 hwirq: 0x20000 chip: INTEL-IR flags: 0x0 parent: domain: VECTOR hwirq: 0x3 chip: APIC flags: 0x0 This was developed to simplify the debugging of the managed affinity changes. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235444.537566163@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-06-19 23:37:17 +00:00
/*
* Copyright 2017 Thomas Gleixner <tglx@linutronix.de>
*
* This file is licensed under the GPL V2.
*/
#include <linux/debugfs.h>
#include <linux/irqdomain.h>
#include <linux/irq.h>
#include "internals.h"
static struct dentry *irq_dir;
struct irq_bit_descr {
unsigned int mask;
char *name;
};
#define BIT_MASK_DESCR(m) { .mask = m, .name = #m }
static void irq_debug_show_bits(struct seq_file *m, int ind, unsigned int state,
const struct irq_bit_descr *sd, int size)
{
int i;
for (i = 0; i < size; i++, sd++) {
if (state & sd->mask)
seq_printf(m, "%*s%s\n", ind + 12, "", sd->name);
}
}
#ifdef CONFIG_SMP
static void irq_debug_show_masks(struct seq_file *m, struct irq_desc *desc)
{
struct irq_data *data = irq_desc_get_irq_data(desc);
struct cpumask *msk;
msk = irq_data_get_affinity_mask(data);
seq_printf(m, "affinity: %*pbl\n", cpumask_pr_args(msk));
#ifdef CONFIG_GENERIC_PENDING_IRQ
msk = desc->pending_mask;
seq_printf(m, "pending: %*pbl\n", cpumask_pr_args(msk));
#endif
}
#else
static void irq_debug_show_masks(struct seq_file *m, struct irq_desc *desc) { }
#endif
static const struct irq_bit_descr irqchip_flags[] = {
BIT_MASK_DESCR(IRQCHIP_SET_TYPE_MASKED),
BIT_MASK_DESCR(IRQCHIP_EOI_IF_HANDLED),
BIT_MASK_DESCR(IRQCHIP_MASK_ON_SUSPEND),
BIT_MASK_DESCR(IRQCHIP_ONOFFLINE_ENABLED),
BIT_MASK_DESCR(IRQCHIP_SKIP_SET_WAKE),
BIT_MASK_DESCR(IRQCHIP_ONESHOT_SAFE),
BIT_MASK_DESCR(IRQCHIP_EOI_THREADED),
};
static void
irq_debug_show_chip(struct seq_file *m, struct irq_data *data, int ind)
{
struct irq_chip *chip = data->chip;
if (!chip) {
seq_printf(m, "chip: None\n");
return;
}
seq_printf(m, "%*schip: %s\n", ind, "", chip->name);
seq_printf(m, "%*sflags: 0x%lx\n", ind + 1, "", chip->flags);
irq_debug_show_bits(m, ind, chip->flags, irqchip_flags,
ARRAY_SIZE(irqchip_flags));
}
static void
irq_debug_show_data(struct seq_file *m, struct irq_data *data, int ind)
{
seq_printf(m, "%*sdomain: %s\n", ind, "",
data->domain ? data->domain->name : "");
seq_printf(m, "%*shwirq: 0x%lx\n", ind + 1, "", data->hwirq);
irq_debug_show_chip(m, data, ind + 1);
#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
if (!data->parent_data)
return;
seq_printf(m, "%*sparent:\n", ind + 1, "");
irq_debug_show_data(m, data->parent_data, ind + 4);
#endif
}
static const struct irq_bit_descr irqdata_states[] = {
BIT_MASK_DESCR(IRQ_TYPE_EDGE_RISING),
BIT_MASK_DESCR(IRQ_TYPE_EDGE_FALLING),
BIT_MASK_DESCR(IRQ_TYPE_LEVEL_HIGH),
BIT_MASK_DESCR(IRQ_TYPE_LEVEL_LOW),
BIT_MASK_DESCR(IRQD_LEVEL),
BIT_MASK_DESCR(IRQD_ACTIVATED),
BIT_MASK_DESCR(IRQD_IRQ_STARTED),
BIT_MASK_DESCR(IRQD_IRQ_DISABLED),
BIT_MASK_DESCR(IRQD_IRQ_MASKED),
BIT_MASK_DESCR(IRQD_IRQ_INPROGRESS),
BIT_MASK_DESCR(IRQD_PER_CPU),
BIT_MASK_DESCR(IRQD_NO_BALANCING),
BIT_MASK_DESCR(IRQD_MOVE_PCNTXT),
BIT_MASK_DESCR(IRQD_AFFINITY_SET),
BIT_MASK_DESCR(IRQD_SETAFFINITY_PENDING),
BIT_MASK_DESCR(IRQD_AFFINITY_MANAGED),
BIT_MASK_DESCR(IRQD_MANAGED_SHUTDOWN),
BIT_MASK_DESCR(IRQD_FORWARDED_TO_VCPU),
BIT_MASK_DESCR(IRQD_WAKEUP_STATE),
BIT_MASK_DESCR(IRQD_WAKEUP_ARMED),
};
static const struct irq_bit_descr irqdesc_states[] = {
BIT_MASK_DESCR(_IRQ_NOPROBE),
BIT_MASK_DESCR(_IRQ_NOREQUEST),
BIT_MASK_DESCR(_IRQ_NOTHREAD),
BIT_MASK_DESCR(_IRQ_NOAUTOEN),
BIT_MASK_DESCR(_IRQ_NESTED_THREAD),
BIT_MASK_DESCR(_IRQ_PER_CPU_DEVID),
BIT_MASK_DESCR(_IRQ_IS_POLLED),
BIT_MASK_DESCR(_IRQ_DISABLE_UNLAZY),
};
static const struct irq_bit_descr irqdesc_istates[] = {
BIT_MASK_DESCR(IRQS_AUTODETECT),
BIT_MASK_DESCR(IRQS_SPURIOUS_DISABLED),
BIT_MASK_DESCR(IRQS_POLL_INPROGRESS),
BIT_MASK_DESCR(IRQS_ONESHOT),
BIT_MASK_DESCR(IRQS_REPLAY),
BIT_MASK_DESCR(IRQS_WAITING),
BIT_MASK_DESCR(IRQS_PENDING),
BIT_MASK_DESCR(IRQS_SUSPENDED),
};
static int irq_debug_show(struct seq_file *m, void *p)
{
struct irq_desc *desc = m->private;
struct irq_data *data;
raw_spin_lock_irq(&desc->lock);
data = irq_desc_get_irq_data(desc);
seq_printf(m, "handler: %pf\n", desc->handle_irq);
seq_printf(m, "status: 0x%08x\n", desc->status_use_accessors);
irq_debug_show_bits(m, 0, desc->status_use_accessors, irqdesc_states,
ARRAY_SIZE(irqdesc_states));
seq_printf(m, "istate: 0x%08x\n", desc->istate);
irq_debug_show_bits(m, 0, desc->istate, irqdesc_istates,
ARRAY_SIZE(irqdesc_istates));
seq_printf(m, "ddepth: %u\n", desc->depth);
seq_printf(m, "wdepth: %u\n", desc->wake_depth);
seq_printf(m, "dstate: 0x%08x\n", irqd_get(data));
irq_debug_show_bits(m, 0, irqd_get(data), irqdata_states,
ARRAY_SIZE(irqdata_states));
seq_printf(m, "node: %d\n", irq_data_get_node(data));
irq_debug_show_masks(m, desc);
irq_debug_show_data(m, data, 0);
raw_spin_unlock_irq(&desc->lock);
return 0;
}
static int irq_debug_open(struct inode *inode, struct file *file)
{
return single_open(file, irq_debug_show, inode->i_private);
}
static const struct file_operations dfs_irq_ops = {
.open = irq_debug_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc)
{
char name [10];
if (!irq_dir || !desc || desc->debugfs_file)
return;
sprintf(name, "%d", irq);
desc->debugfs_file = debugfs_create_file(name, 0444, irq_dir, desc,
&dfs_irq_ops);
}
void irq_remove_debugfs_entry(struct irq_desc *desc)
{
if (desc->debugfs_file)
debugfs_remove(desc->debugfs_file);
}
static int __init irq_debugfs_init(void)
{
struct dentry *root_dir;
int irq;
root_dir = debugfs_create_dir("irq", NULL);
if (!root_dir)
return -ENOMEM;
irq_domain_debugfs_init(root_dir);
irq_dir = debugfs_create_dir("irqs", root_dir);
irq_lock_sparse();
for_each_active_irq(irq)
irq_add_debugfs_entry(irq, irq_to_desc(irq));
irq_unlock_sparse();
return 0;
}
__initcall(irq_debugfs_init);