Preparing Linux Real-Time Kernel and Tuning Robotics Platform with Modern ARM..
summary
Mainline 6.1/6.3 kernel with PREEMPT_RT is built for a Qualcomm RB5 (QRB5165) and reveals driver bugs: spinlocks become sleepable, PM-runtime calls and GFP_ATOMIC can sleep, and CPUidle interactions break probe paths. Debugging uses cyclictest, stress-ng and tracing (hardware-latency tracer, rtla) to find wake sources. Tuning (cpuset cgroups, isolcpus, nohz_full, performance governor, disable deep-sleep, IRQ affinity) cuts maximum latencies from ~1 ms down to single-digit microseconds — e.g. tuned RT shows ~4 µs max vs ~38 µs for tuned vanilla under load.
AI-written summary · about
chapters (12)
- 0:00Introduction to RT kernel
- 1:24Kernel configuration
- 3:06Driver debugging tools
- 5:23Spinlock and IRQ issues
- 7:45PM runtime and memory issues
- 9:34Evaluation and measurement
- 12:49Initial latency results
- 15:17System tuning techniques
- 19:21Tuned performance results
- 21:42Partitioning and benchmarks
- 24:00Vanila vs RT kernel comparison
- 25:41Advanced debugging tools
related talks
53mPREEMPT_RT - How Not to Break It.
46mPREEMPT_RT - how not to break it.
36mStatus of Embedded Linux
39mCloudLinux runtime kernel update for ARM growth difficulties
45mWhy Won't My CPU Sleep? Debugging CPUIdle Mysteries on ARM SoCs
46mKernel Hardening for 32-bit Arm Processors
44mKernel TEE subsystem BoF
31mSponsored Session: Can We Do Better than Shipping 4 Year Old Software in Products?