Introduction to the Linux kernel

1. Preface

This article briefly describes the functions of the Linux kernel, and what parts of the Linux kernel are composed, and gives a brief description of the main functions completed by each part.

2. Functions of the kernel

The kernel is a middle tier of hardware and software, which is the function of passing application requests to hardware.

• From the perspective of the application

Any requests made by the application are abstracted by the kernel, masking the details of the operation, so the kernel is an enhancement to the hardware for the application.

• From the perspective of multi-process concurrency execution

When multiple processes are executing, the kernel needs to allocate and manage resources such as memory, so the kernel is a resource manager

• From the angle of the system call

Applications can request the kernel to do some functions through system calls, which are like libraries that the application calls

3. Implementation strategy of the kernel

There are two implementation strategies for the kernel:

Microkernel: The kernel only implements the most basic functions, non-basic functions such as file system, memory management, etc. delegated to some independent process processing

Macro kernel: In addition to the most basic functions of the kernel, other functions include file system, memory management, drivers are packaged in the same file

Linux kernel belongs to the macro kernel, but can be plugged into the kernel code or removed from the kernel code.

4. Components of the kernel

Introduction to the Linux kernel