Open Source Summit Europe 2022

Brendan will explain what is different about using Linux in the automotive segment specifically around the boot time requirements and other interesting performance indicators which are maybe different to other industries. We will show how we use yocto/poky with a mix of android derived features as well as genivi/covesa components to implement internally 10 automotive control units in infotainment, telematics, instrument cluster and body domains. The talk will center around how to handle the challenging 2 seconds rear view camera KPI in Linux userspace as well as other lifecycle KPIs (shutdown, suspend to ram) using a relatively classic systemd/glibc Linux whilst having modern security features enabled (secure boot, dm-verity, ipsec & selinux). We will especially focus on how we configure multiple different SOC platforms to achieve these goals and what hardware characteristics are most important to achieve fast boot times. The talk will then discuss the specific patches and configuration BMW proposed to systemd specifically to allow an 'early' boot target. We would also like to use the opportunity to understand if other industries have similar issues around boot times and if we could work together to jointly maintain a systemd 'fast' profile.

Systemd is the init daemon of choice for all but the smallest of embedded Linux project. Systemd is complex and can do many things (*). In this presentation I focus on the features most relevant to embedded devices

I begin with a review of the basics: Units, Targets, Services, and dependencies. Then I build on that to look at:
• Loading services on-demand, rather than just loading everything at boot time
• Controlling resource usage of daemons, following the principle of least privilege
• Using watchdogs to protect against lockups of key services
• Optimizing boot time

There will be demos, based on images built using Yocto Project

(*) Some people say systemd does too many things, but it’s up to you to decide