Linux 7.2 Kernel Released with Cache-Aware Scheduling and Raspberry Pi GPU Power Management

Linux 7.2 Release Overview

The Linux kernel version 7.2 has been officially released, following its regular development schedule. This release cycle was noted as one of the busiest, comparable to the 6.7 cycle, indicating a continued high pace of development and integration into the kernel.

Key Technical Advancements

Significant technical achievements in Linux 7.2 include the implementation of cache-aware scheduling, which optimizes how tasks utilize CPU caches. Improvements were also made to MGLRU (Multi-Generational Least Recently Used) memory management. The release introduces the concept of sub-schedulers for sched_ext and automatic creation of multi-size transparent hugepages, enhancing system performance and resource management.

GPU Enhancements and Power Management

Igalia contributed to the release, notably with the DRM scheduler fair policy, which aims to improve GPU sharing scenarios. However, due to a last-minute regression report, this policy is currently opt-in rather than default. Additionally, runtime power management support for GPUs in the Raspberry Pi 4 and 5 has been integrated, allowing for more efficient power usage on these devices. Improvements were also made to sched_ext and futex, alongside general bug fixes.

Improved sched_ext Observability

The observability of sched_ext has been enhanced to simplify debugging. When a custom sched_ext scheduler encounters a runtime error, the kernel now prioritizes dumping the status of the exit CPU and surfaces its CPU ID directly to BPF schedulers and userspace tools. This mitigation addresses previous issues where buffer size limits could truncate diagnostic dumps on high-core systems.