Book Image

Mastering Embedded Linux Programming

By : Chris Simmonds
Book Image

Mastering Embedded Linux Programming

By: Chris Simmonds

Overview of this book

Mastering Embedded Linux Programming takes you through the product cycle and gives you an in-depth description of the components and options that are available at each stage. You will begin by learning about toolchains, bootloaders, the Linux kernel, and how to configure a root filesystem to create a basic working device. You will then learn how to use the two most commonly used build systems, Buildroot and Yocto, to speed up and simplify the development process. Building on this solid base, the next section considers how to make best use of raw NAND/NOR flash memory and managed flash eMMC chips, including mechanisms for increasing the lifetime of the devices and to perform reliable in-field updates. Next, you need to consider what techniques are best suited to writing applications for your device. We will then see how functions are split between processes and the usage of POSIX threads, which have a big impact on the responsiveness and performance of the final device The closing sections look at the techniques available to developers for profiling and tracing applications and kernel code using perf and ftrace.
Table of Contents (16 chapters)
15
Index

Helgrind

This is a thread error detector for detecting synchronization errors in C, C++, and Fortran programs that include POSIX threads.

Helgrind can detect three classes of error. Firstly, it can detect the incorrect use of the API. For example, it can unlock a mutex that is already unlocked, unlock a mutex that was locked by a different thread, not checking the return value of certain Pthread functions. Secondly, it monitors the order in which threads acquire locks and thus detects potential deadlocks which could arise from the formation of cycles of locks. Finally, it detects data races which can happen when two threads access a shared memory location without using suitable locks or other synchronization to ensure single-threaded access.

Using Helgrind is simple, you just need this command:

# valgrind --tool=helgrind <program>

It prints problems and potential problems as it finds them. You can direct these messages to a file by adding --log-file=<filename>.