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Date: Tue, 5 Mar 2024 13:54:59 -0800
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Subject: Re: [RFC PATCH net-next v6 02/15] net: page_pool: create hooks for
 custom page providers
To: Mina Almasry <almasrymina@google.com>, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
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Cc: "David S. Miller" <davem@davemloft.net>,
 Eric Dumazet <edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>,
 Paolo Abeni <pabeni@redhat.com>, Jonathan Corbet <corbet@lwn.net>,
 Richard Henderson <richard.henderson@linaro.org>,
 Ivan Kokshaysky <ink@jurassic.park.msu.ru>, Matt Turner
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 Praveen Kaligineedi <pkaligineedi@google.com>
References: <20240305020153.2787423-1-almasrymina@google.com>
 <20240305020153.2787423-3-almasrymina@google.com>
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From: David Wei <dw@davidwei.uk>
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On 2024-03-04 18:01, Mina Almasry wrote:
> +struct memory_provider_ops {
> +	int (*init)(struct page_pool *pool);
> +	void (*destroy)(struct page_pool *pool);
> +	struct page *(*alloc_pages)(struct page_pool *pool, gfp_t gfp);
> +	bool (*release_page)(struct page_pool *pool, struct page *page);

For ZC Rx we added a scrub() function to memory_provider_ops that is
called from page_pool_scrub(). Does TCP devmem not custom behaviour
waiting for all netmem_refs to return before destroying the page pool?
What happens if e.g. application crashes?