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

Filesystem choices

So far, we have looked at the technology behind solid-state memory and at the many types of filesystems. Now, it is time to summarize the options that are available. In most cases, you will be able to divide your storage requirements into these three categories:

  • Permanent, read-write data: Runtime configuration, network parameters, passwords, data logs, and user data
  • Permanent, read-only data: Programs, libraries, and configurations files that are constant; for example, the root filesystem
  • Volatile data: Temporary storage; for example, /tmp

The choices for read-write storage are as follows:

  • NOR: UBIFS or JFFS2
  • NAND: UBIFS, JFFS2, or YAFFS2
  • eMMC: ext4 or F2FS

For read-only storage, you can use any of these, mounted with the ro attribute. Additionally, if you want to save space, you could use SquashFS. Finally, for volatile storage, there is only one choice: tmpfs.