genirq: Expose interrupt information through sysfs
Information about interrupts is exposed via /proc/interrupts, but the
format of that file has changed over kernel versions and differs across
architectures. It also has varying column numbers depending on hardware.
That all makes it hard for tools to parse.
To solve this, expose the information through sysfs so each irq attribute
is in a separate file in a consistent, machine parsable way.
This feature is only available when both CONFIG_SPARSE_IRQ and
CONFIG_SYSFS are enabled.
Examples:
/sys/kernel/irq/18/actions: i801_smbus,ehci_hcd:usb1,uhci_hcd:usb7
/sys/kernel/irq/18/chip_name: IR-IO-APIC
/sys/kernel/irq/18/hwirq: 18
/sys/kernel/irq/18/name: fasteoi
/sys/kernel/irq/18/per_cpu_count: 0,0
/sys/kernel/irq/18/type: level
/sys/kernel/irq/25/actions: ahci0
/sys/kernel/irq/25/chip_name: IR-PCI-MSI
/sys/kernel/irq/25/hwirq: 512000
/sys/kernel/irq/25/name: edge
/sys/kernel/irq/25/per_cpu_count: 29036,0
/sys/kernel/irq/25/type: edge
[ tglx: Moved kobject_del() under sparse_irq_lock, massaged code comments
and changelog ]
Signed-off-by: Craig Gallek <kraig@google.com>
Cc: David Decotigny <decot@google.com>
Link: http://lkml.kernel.org/r/1473783291-122873-1-git-send-email-kraigatgoog@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index b51beeb..c9be579 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -2,6 +2,7 @@
#define _LINUX_IRQDESC_H
#include <linux/rcupdate.h>
+#include <linux/kobject.h>
/*
* Core internal functions to deal with irq descriptors
@@ -43,6 +44,7 @@
* @force_resume_depth: number of irqactions on a irq descriptor with
* IRQF_FORCE_RESUME set
* @rcu: rcu head for delayed free
+ * @kobj: kobject used to represent this struct in sysfs
* @dir: /proc/irq/ procfs entry
* @name: flow handler name for /proc/interrupts output
*/
@@ -88,6 +90,7 @@
#endif
#ifdef CONFIG_SPARSE_IRQ
struct rcu_head rcu;
+ struct kobject kobj;
#endif
int parent_irq;
struct module *owner;