Re: [PATCH v2] blk-mq: use a housekeeping CPU for passthrough requests on isolated hctxs

From: Christoph Hellwig

Date: Wed Nov 04 2026 - 02:22:31 EST


On Tue, Nov 03, 2026 at 05:37:48PM +0100, Sebastian Andrzej Siewior wrote:
> What about
> guard(rcu);
> for_each_cpu_and(cpu, cpu_online_mask, housekeeping_cpumask(HK_TYPE_MANAGED_IRQ)) {
> if (!cpu_is_isolated(cpu)
> break;
> }
>
> this ends up with one less function call ;)

Please avoid this completely unreadable and unaditable guard crap.

How is anyone supposed to understand that above mess?