Re: [RFC PATCH] rhashtable: Bounce deferred worker kick through irq_work when insecure_elasticity is set

Herbert Xu
2026-04-20T08:44:35Z

On Sun, Apr 19, 2026 at 08:19:33AM -1000, Tejun Heo wrote:
>
> +/*
> + * Kick the deferred rehash worker. With insecure_elasticity the caller may
> + * hold a raw spinlock. schedule_work() under a raw spinlock records
> + * caller_lock -> pool->lock -> pi_lock -> rq->__lock. If any of these
> + * locks is acquired in the reverse direction elsewhere, the cycle closes.
> + * Bounce through irq_work so schedule_work() runs from hard IRQ context
> + * with the caller's lock no longer held.
> + */
> +static void rhashtable_kick_deferred_worker(struct rhashtable *ht)
> +{
> + if (ht->p.insecure_elasticity)
> + irq_work_queue(&ht->run_irq_work);
> + else
> + schedule_work(&ht->run_work);
> +}

Can we just do irq_work_queue unconditionally?

Thanks,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
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