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Date: Thu, 5 Sep 2024 17:20:29 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Lorenzo Bianconi <lorenzo@kernel.org>
Cc: Alexander Lobakin <aleksander.lobakin@intel.com>, Alexei Starovoitov
 <ast@kernel.org>, Daniel Borkmann <daniel@iogearbox.net>, Andrii Nakryiko
 <andrii@kernel.org>, Daniel Xu <dxu@dxuuu.xyz>, John Fastabend
 <john.fastabend@gmail.com>, Jesper Dangaard Brouer <hawk@kernel.org>,
 Martin KaFai Lau <martin.lau@linux.dev>, "David S. Miller"
 <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>, Paolo Abeni
 <pabeni@redhat.com>, bpf@vger.kernel.org, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH bpf-next 0/9] bpf: cpumap: enable GRO for XDP_PASS
 frames
Message-ID: <20240905172029.5e9ca520@kernel.org>
In-Reply-To: <Ztnj9ujDg4NLZFDm@lore-desk>
References: <20240830162508.1009458-1-aleksander.lobakin@intel.com>
	<20240903135158.7031a3ab@kernel.org>
	<ZteAuB-QjYU6PIf7@lore-desk>
	<Ztnj9ujDg4NLZFDm@lore-desk>
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On Thu, 5 Sep 2024 19:01:42 +0200 Lorenzo Bianconi wrote:
> In particular, the cpumap kthread pinned on cpu 'n' can schedule the
> backlog NAPI associated to cpu 'n'. However according to my understanding
> it seems the backlog NAPI APIs (in process_backlog()) do not support GRO,
> right? Am I missing something?

I meant to use the struct directly, not to schedule it. All you need
is GRO - feed it packets, flush it. 
But maybe you can avoid the netdev allocation and patch 3 in other ways.
Using backlog NAPI was just the first thing that came to mind.