Book Image

Embedded Linux Development Using Yocto Project Cookbook - Second Edition

By : Alex Gonzalez
Book Image

Embedded Linux Development Using Yocto Project Cookbook - Second Edition

By: Alex Gonzalez

Overview of this book

The Yocto Project has become the de facto distribution build framework for reliable and robust embedded systems with a reduced time to market.You'll get started by working on a build system where you set up Yocto, create a build directory, and learn how to debug it. Then, you'll explore everything about the BSP layer, from creating a custom layer to debugging device tree issues. In addition to this, you’ll learn how to add a new software layer, packages, data, scripts, and configuration files to your system. You will then cover topics based on application development, such as using the Software Development Kit and how to use the Yocto project in various development environments. Toward the end, you will learn how to debug, trace, and profile a running system. This second edition has been updated to include new content based on the latest Yocto release.
Table of Contents (13 chapters)
Title Page
Packt Upsell

Using static kernel tracing

The Linux kernel is continuously being instrumented with static probe points called tracepoints, which when disabled have a negligible overhead. They allow us to record more information than the function tracer we saw in Chapter 2, The BSP Layer. Tracepoints are used by multiple tracing and profiling tools in Yocto.

This recipe will explain how to use and define static tracepoints independently of user space tools.

Getting ready

Static tracepoints can be instrumented using custom kernel modules, and also through the event tracing infrastructure. Enabling any of the tracing features in the kernel will create a /sys/kernel/debug/tracing/ directory; for example, the function tracing feature as explained in the Using the kernel function tracing system in Chapter 2, The BSP Layer.

So before continuing with this recipe, you need to configure the function tracing feature in the Linux kernel as explained before.

How to do it...

The static tracing functionality is exposed via...