Re: [PATCH 2/2] sched_ext: Maintain an online cid mask in the scheduler arena

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] cleanup: mixing goto-based error handling with scoped_guard
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commit 60f284d9a4235976e8b99adae7dd47c5aa1ab1af
Author: Tejun Heo <tj@kernel.org>
Subject: sched_ext: Maintain an online cid mask in the scheduler arena

This commit adds a kernel-maintained online cid mask to the scheduler's
arena, which is allocated alongside per-CPU scratch masks. This mask is
updated during hotplug transitions, allowing custom-mapped schedulers to
accurately learn which cids are online without needing a restart.

> diff --git a/kernel/sched/ext/sub.c b/kernel/sched/ext/sub.c
> --- a/kernel/sched/ext/sub.c
> +++ b/kernel/sched/ext/sub.c
> @@ -1805,6 +1805,12 @@ void scx_sub_enable_workfn(struct kthread_work *work)
>  		goto err_disable;
>  	}
>  
> +	scoped_guard(cpus_read_lock) {
> +		ret = scx_alloc_kern_arena_objs(sch);
> +		if (ret)
> +			goto err_disable;

[Severity: Low]
Does this code mix goto-based error handling with scope-based cleanup in
scx_sub_enable_workfn()? 

The cleanup subsystem guidelines specify that functions should either convert
all resources that need a goto cleanup to scope-based cleanup, or convert
none of them. Mixing goto error labels (like goto err_disable) with
scoped_guard within the same function creates confusing ownership semantics.

> +	}
> +
>  	if (sch->ops.init) {
>  		ret = SCX_CALL_OP_RET(sch, init, NULL);
>  		if (ret) {

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Sashiko AI review · https://sashiko.dev/#/patchset/20260914234259.3585373-1-tj@kernel.org?part=2