At the Linux Plumbers Conference in 2023, Thomas Gleixner announced that the addition of realtime support to Linux is almost complete. The main challenge left to tackle is printk(), which handles printing messages to system consoles and logs. Gleixner described printk() as “stupid” and explained that it is currently synchronous, causing unnecessary latency and hindering the goals of the realtime work. To resolve this issue, the realtime developers have moved printk() output into separate threads, but a more robust solution is needed. Several patch sets are currently being developed to address the printk() problem, with the hope of having the realtime preemption code in the mainline by late 2024.
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