Book Image

Mastering Embedded Linux Programming - Third Edition

By : Frank Vasquez, Chris Simmonds
5 (3)
Book Image

Mastering Embedded Linux Programming - Third Edition

5 (3)
By: Frank Vasquez, Chris Simmonds

Overview of this book

If you’re looking for a book that will demystify embedded Linux, then you’ve come to the right place. Mastering Embedded Linux Programming is a fully comprehensive guide that can serve both as means to learn new things or as a handy reference. The first few chapters of this book will break down the fundamental elements that underpin all embedded Linux projects: the toolchain, the bootloader, the kernel, and the root filesystem. After that, you will learn how to create each of these elements from scratch and automate the process using Buildroot and the Yocto Project. As you progress, the book will show you how to implement an effective storage strategy for flash memory chips and install updates to a device remotely once it’s deployed. You’ll also learn about the key aspects of writing code for embedded Linux, such as how to access hardware from apps, the implications of writing multi-threaded code, and techniques to manage memory in an efficient way. The final chapters demonstrate how to debug your code, whether it resides in apps or in the Linux kernel itself. You’ll also cover the different tracers and profilers that are available for Linux so that you can quickly pinpoint any performance bottlenecks in your system. By the end of this Linux book, you’ll be able to create efficient and secure embedded devices using Linux.
Table of Contents (27 chapters)
1
Section 1: Elements of Embedded Linux
10
Section 2: System Architecture and Design Decisions
18
Section 3: Writing Embedded Applications
22
Section 4: Debugging and Optimizing Performance

Using BPF

BPF (Berkeley Packet Filter) is a technology that was first introduced in 1992 to capture, filter, and analyze network traffic. In 2013, Alexi Starovoitov undertook a rewrite of BPF with help from Daniel Borkmann. Their work, then known as eBPF (extended BPF), was merged into the kernel in 2014, where it has been available since Linux 3.15. BPF provides a sandboxed execution environment for running programs inside the Linux kernel. BPF programs are written in C and are just-in-time (JIT) compiled to native code. Before that can happen, the intermediate BPF bytecode must first pass through a series of safety checks so that a program cannot crash the kernel.

Despite its networking origins, BPF is now a general-purpose virtual machine running inside the Linux kernel. By making it easy to run small programs on specific kernel and application events, BPF has quickly emerged as the most powerful tracer for Linux. Like what cgroups did for containerized deployments, BPF has the...