Linux Kernel Development, Third Edition

7. Interrupts and Interrupt Handlers

A core responsibility of any operating system kernel is managing the hardware connected to the machine—hard drives and Blu-ray discs, keyboards and mice, 3D processors and wireless radios. To meet this responsibility, the kernel needs to communicate with the machine’s individual devices. Given that processors can be orders of magnitudes faster than the hardware they talk to, it is not ideal for the kernel to issue a request and wait for a response from the significantly slower hardware. Instead, because the hardware is comparatively slow to respond, the kernel must be free to go and handle other work, dealing with the hardware only after that hardware has actually completed its work.

How can the processor ...