Processes are a fundamental abstraction of the operating system. To support
processes, the OS uses two key data structures (task_struct and
thread_info), as well as a host of auxiliary functions for
managing processes in the system.
arch/arm/include/asm/thread_info.h - Definition of the
thread_info structure.
include/linux/sched.h - Definition of the
task_struct structure, plus many process management functions.
arch/arm/include/asm/switch_to.h - Defintion of the process switch routine
arch/arm/kernel/entry-armv.S - Implementation of the
assembly level process switch routine (__switch_to)