Sign In Start Free Trial
Account

Add to playlist

Create a Playlist

Modal Close icon
You need to login to use this feature.
  • Book Overview & Buying Mastering Embedded Linux Programming
  • Table Of Contents Toc
  • Feedback & Rating feedback
Mastering Embedded Linux Programming

Mastering Embedded Linux Programming - Second Edition

By : Chris Simmonds
4.3 (12)
close
close
Mastering Embedded Linux Programming

Mastering Embedded Linux Programming

4.3 (12)
By: Chris Simmonds

Overview of this book

Embedded Linux runs many of the devices we use every day, from smart TVs to WiFi routers, test equipment to industrial controllers - all of them have Linux at their heart. Linux is a core technology in the implementation of the inter-connected world of the Internet of Things. You will begin by learning about the fundamental elements that underpin all embedded Linux projects: the toolchain, the bootloader, the kernel, and the root filesystem. You’ll see how to create each of these elements from scratch, and how to automate the process using Buildroot and the Yocto Project. Moving on, you’ll find out how to implement an effective storage strategy for flash memory chips, and how to install updates to the device remotely once it is deployed. You’ll also get to know the key aspects of writing code for embedded Linux, such as how to access hardware from applications, the implications of writing multi-threaded code, and techniques to manage memory in an efficient way. The final chapters show you how to debug your code, both in applications and in the Linux kernel, and how to profile the system so that you can look out for performance bottlenecks. By the end of the book, you will have a complete overview of the steps required to create a successful embedded Linux system.
Table of Contents (23 chapters)
close
close
Title Page
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Kernel space memory layout


Kernel memory is managed in a fairly straightforward way. It is not demand-paged, which means that for every allocation using kmalloc() or a similar function, there is real physical memory. Kernel memory is never discarded or paged out.

Some architectures show a summary of the memory mapping at boot time in the kernel log messages. This trace is taken from a 32-bit ARM device (a BeagleBone Black):

Memory: 511MB = 511MB total 
Memory: 505980k/505980k available, 18308k reserved, 0K highmem 
Virtual kernel memory layout: 
  vector  : 0xffff0000 - 0xffff1000   (   4 kB) 
  fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB) 
  vmalloc : 0xe0800000 - 0xff000000   ( 488 MB) 
  lowmem  : 0xc0000000 - 0xe0000000   ( 512 MB) 
  pkmap   : 0xbfe00000 - 0xc0000000   (   2 MB) 
  modules : 0xbf800000 - 0xbfe00000   (   6 MB) 
    .text : 0xc0008000 - 0xc0763c90   (7536 kB) 
    .init : 0xc0764000 - 0xc079f700   ( 238 kB) 
    .data : 0xc07a0000 - 0xc0827240   ( 541 kB) 
     .bss ...

Limited Time Offer

$10p/m for 3 months

Get online access to our library of over 7000 practical eBooks and videos, constantly updated with the latest in tech and supported with AI assistants
notes
bookmark Notes and Bookmarks search Search in title playlist Add to playlist download Download options font-size Font size

Change the font size

margin-width Margin width

Change margin width

day-mode Day/Sepia/Night Modes

Change background colour

Close icon Search
Country selected

Close icon Your notes and bookmarks

Confirmation

Modal Close icon
claim successful

Buy this book with your credits?

Modal Close icon
Are you sure you want to buy this book with one of your credits?
Close
YES, BUY

Submit Your Feedback

Modal Close icon
Modal Close icon
Modal Close icon