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Date: Wed, 11 Oct 2023 08:36:17 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Yunsheng Lin <linyunsheng@huawei.com>
Cc: <davem@davemloft.net>, <pabeni@redhat.com>, <netdev@vger.kernel.org>,
 <linux-kernel@vger.kernel.org>, Matthias Brugger <matthias.bgg@gmail.com>,
 AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>,
 Alexei Starovoitov <ast@kernel.org>, Daniel Borkmann
 <daniel@iogearbox.net>, Jesper Dangaard Brouer <hawk@kernel.org>, John
 Fastabend <john.fastabend@gmail.com>,
 <linux-arm-kernel@lists.infradead.org>,
 <linux-mediatek@lists.infradead.org>, <bpf@vger.kernel.org>
Subject: Re: [PATCH net-next v10 0/6] introduce page_pool_alloc() related
 API
Message-ID: <20231011083617.61bba987@kernel.org>
In-Reply-To: <20230922091138.18014-1-linyunsheng@huawei.com>
References: <20230922091138.18014-1-linyunsheng@huawei.com>
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On Fri, 22 Sep 2023 17:11:32 +0800 Yunsheng Lin wrote:
> In [1] & [2] & [3], there are usecases for veth and virtio_net
> to use frag support in page pool to reduce memory usage, and it
> may request different frag size depending on the head/tail
> room space for xdp_frame/shinfo and mtu/packet size. When the
> requested frag size is large enough that a single page can not
> be split into more than one frag, using frag support only have
> performance penalty because of the extra frag count handling
> for frag support.
> 
> So this patchset provides a page pool API for the driver to
> allocate memory with least memory utilization and performance
> penalty when it doesn't know the size of memory it need
> beforehand.

Could you rebase & repost? Patches no longer apply :(