Re: [PATCH v2] workqueue: Automatic affinity scope fallback for single-pod topologies

[Tejun Heo]

Hello, Chuck.

On Wed, Feb 04, 2026 at 09:49:11PM -0500, Chuck Lever wrote:
> +static bool __init cpus_share_cluster(int cpu0, int cpu1)
> +{
> +	return cpumask_test_cpu(cpu0, topology_cluster_cpumask(cpu1));
> +}

Cluster boundary == core boundary for a lot of CPUs. I don't think this is
going to work. Here are a couple options:

- Introduce an affinity level which splits CACHE according to some
  adjustable heuristics.

- Make the NFS workqueue default to WQ_AFFN_CORE (or maybe switch based on
  some heuristics) or switch to a per-cpu workqueue.

Thanks.

-- 
tejun