Re: [PATCH v3 0/3] sched_ext: Improve exit-time diagnostics

[Tejun Heo <tj@kernel.org>]

Hello,

> Changwoo Min (3):
>   sched_ext: Extract scx_dump_cpu() from scx_dump_state()
>   sched_ext: Dump the exit CPU first
>   sched_ext: Expose exit_cpu to BPF and userspace

Applied 1-3 to sched_ext/for-7.2, thank you.

A few things I noticed that might be worth a follow-up:

1. scx_rcu_cpu_stall() takes no cpu, so the captured exit_cpu ends
   up being the detector rather than the stalled one. We could
   probably plumb it through from print_other_cpu_stall(), where
   the stalled cpu is known.

2. scx_hardlockup_irq_workfn() already has the hung cpu locally, so
   passing it via __scx_exit() might be a bit more robust than
   relying on irq_work routing.

3. Minor: "on cpu N" (kernel) vs "on CPU N" (UEI) - the casing
   could probably match.

Thanks.

--
tejun