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Date: Fri, 1 Dec 2023 19:48:29 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Lorenzo Bianconi <lorenzo@kernel.org>, aleksander.lobakin@intel.com
Cc: netdev@vger.kernel.org, davem@davemloft.net, edumazet@google.com,
 pabeni@redhat.com, lorenzo.bianconi@redhat.com, bpf@vger.kernel.org,
 hawk@kernel.org, toke@redhat.com, willemdebruijn.kernel@gmail.com,
 jasowang@redhat.com, sdf@google.com
Subject: Re: [PATCH v3 net-next 2/2] xdp: add multi-buff support for xdp
 running in generic mode
Message-ID: <20231201194829.428a96da@kernel.org>
In-Reply-To: <c9ee1db92c8baa7806f8949186b43ffc13fa01ca.1701437962.git.lorenzo@kernel.org>
References: <cover.1701437961.git.lorenzo@kernel.org>
	<c9ee1db92c8baa7806f8949186b43ffc13fa01ca.1701437962.git.lorenzo@kernel.org>
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On Fri,  1 Dec 2023 14:48:26 +0100 Lorenzo Bianconi wrote:
> Similar to native xdp, do not always linearize the skb in
> netif_receive_generic_xdp routine but create a non-linear xdp_buff to be
> processed by the eBPF program. This allow to add  multi-buffer support
> for xdp running in generic mode.

Hm. How close is the xdp generic code to veth?
I wonder if it'd make sense to create a page pool instance for each
core, we could then pass it into a common "reallocate skb into a
page-pool backed, fragged form" helper. Common between this code
and veth? Perhaps we could even get rid of the veth page pools
and use the per cpu pools there?