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

Mounting the root filesystem using NFS

If your device has a network interface, it is often useful to mount the root filesystem over the network during development. It gives you access to the almost unlimited storage on your host machine, so you can add in debug tools and executables with large symbol tables. As an added bonus, updates made to the root filesystem on the development machine are made available on the target immediately. You can also access all the target's log files from the host.

To begin with, you need to install and configure an NFS server on your host. On Ubuntu, the package to install is named nfs-kernel-server:

$ sudo apt install nfs-kernel-server

The NFS server needs to be told which directories are being exported to the network; this is controlled by /etc/exports. There is one line for each export. The format is described in the manual page exports(5). As an example, to export the root filesystem on my host, I have this:

/home/chris/rootfs *(rw...