Re: [PATCH] sched/mmcid: Fix affinity-triggered switch back to per-task mode

[Hui Su]

> Thomas, I recall you had tests for those state transitions when
> rewriting rseq mm_cid. Were those local or did they make it upstream ?

Thanks for the feedback.

I checked the current rseq selftests and the related MM CID history.
Thomas' January [0/4] series mentions a thread-pool emulator which was used
to stress-test the ownership transitions. The series did not include a
selftest patch, and I couldn't find equivalent transition coverage in the
current upstream tools/testing/selftests/rseq/.

In particular, I couldn't find a test covering the affinity-expansion case
which switches ownership from per-CPU back to per-task. Unless I missed an
existing test, I'll add a focused selftest for this case and send a v2.

Thomas, if that emulator is still available, or if there is a preferred way
to exercise these transitions, I'd be happy to use it as a reference for
the selftest.

Thanks,
Hui