Showing posts with label irq. Show all posts
Showing posts with label irq. Show all posts

Saturday, May 11, 2019

How do I list all IRQS currently used under Linux?

An interrupt request (IRQ) is a hardware signal sent to the processor instructing it to suspend its
current activity and handle some external event, such as a keyboard input or a mouse movement. In
x86 based computer systems, IRQs are numbered from 0 to 15. Newer computers, including x86-64
systems, provide more than these 16 interrupts (usually 24). Some interrupts are reserved for
specific purposes, such as the keyboard and the real-time clock; others have common uses but may
be reassigned; and some are left available for extra devices that may be added to the system.
Here is a list of the IRQs and their common purposes in the x86 system:

irq list and purpose
There is a file called /proc/interrupts. The proc file system is a pseudo file system which is used as an
interface to kernel data structures. It is commonly mounted at /proc.

This is used to record the number of interrupts per each IRQ on (at least) the i386 architecture. Very
easy to read formatting, done in ASCII.

Display /proc/interrupts

Use cat or less command:

$ cat /proc/interrupts