Re: Re: [PATCH] sched_ext:SCX is preemptible by the Fair scheduler

[Andrea Righi]

On Sat, Jun 13, 2026 at 01:32:28AM +0800, cjian720 wrote:
> Hi Andrea, While this callback will be phased out eventually, SCX is still a relatively new scheduling framework. Incomplete preemption reason enums make it hard to analyze interactions between different schedulers, and filling this gap greatly boosts observability for existing SCX workloads. This patch does not touch core scheduling logic, carries zero performance overhead, and adds negligible long-term maintenance cost. 

You can get the same information directly from BPF using the sched_switch
tracepoint and looking at prev->sched_class and next->sched_class. As I
mentioned, ops.cpu_release() is a deprecated API, so I don't see much value
updating/improving it.

Thanks,
-Andrea