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Date:   Thu, 30 Mar 2023 22:15:26 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     davem@davemloft.net
Cc:     netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com,
        hawk@kernel.org, ilias.apalodimas@linaro.org
Subject: Re: [RFC net-next 1/2] page_pool: allow caching from safely
 localized NAPI
Message-ID: <20230330221526.36a5c7e1@kernel.org>
In-Reply-To: <20230331043906.3015706-1-kuba@kernel.org>
References: <20230331043906.3015706-1-kuba@kernel.org>
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On Thu, 30 Mar 2023 21:39:05 -0700 Jakub Kicinski wrote:
> +/* If caller didn't allow direct recycling check if we have other reasons
> + * to believe that the producer and consumer can't race.
> + *
> + * Result is only meaningful in softirq context.
> + */
> +static bool page_pool_safe_producer(struct page_pool *pool)
> +{
> +	struct napi_struct *napi = pool->p.napi;
> +
> +	return napi && READ_ONCE(napi->list_owner) == smp_processor_id();

Herm, this also needs && !in_hardirq()