Re: [PATCHSET sched_ext/for-7.2] sched_ext: cid/cmask interface prep

[Andrea Righi <arighi@nvidia.com>]

On Wed, Jun 03, 2026 at 07:21:50AM -1000, Tejun Heo wrote:
> Hello,
> 
> Three preparatory changes to the cid/cmask interface that landed in for-7.2
> this cycle - a helper-argument reorder, two new helpers, and a kfunc
> return-type change. Posting ahead of the merge window, in particular the
> scx_bpf_kick_cid() return-type change in patch 3 - it changes a kfunc's
> signature and is cleaner to settle before 7.2 ships.
> 
> - Patch 1 reorders the single-cid cmask helpers to (cid, mask), matching the
>   kernel's index-first bit and cpumask predicates.
> - Patch 2 adds scx_cmask_test() and scx_cmask_for_each_cid().
> - Patch 3 switches scx_bpf_kick_cid() from void to s32 so future cap
>   enforcement can surface failures. The cid interface has no external users
>   yet, so the ABI change is safe now.
> 
> These are extracted from the in-development sub-scheduler series. Nothing
> here depends on the rest of that work.

I sent a comment about patch 3, other than that looks good to me (and thanks for
the cid / mask reordering).

Reviewed-by: Andrea Righi <arighi@nvidia.com>

Thanks,
-Andrea