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From:   Matteo Croce <mcroce@linux.microsoft.com>
Date:   Mon, 22 Mar 2021 20:38:40 +0100
Message-ID: <CAFnufp0t3EzB=kSbCFax4b=TNbvPp=JS1PaZAzM5F4-RfoCbRQ@mail.gmail.com>
Subject: Re: [PATCH net-next 3/6] page_pool: DMA handling and allow to
 recycles frames via SKB
To:     netdev@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org,
        Jonathan Lemon <jonathan.lemon@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Ilias Apalodimas <ilias.apalodimas@linaro.org>,
        Jesper Dangaard Brouer <hawk@kernel.org>,
        Lorenzo Bianconi <lorenzo@kernel.org>,
        Saeed Mahameed <saeedm@nvidia.com>,
        David Ahern <dsahern@gmail.com>,
        Saeed Mahameed <saeed@kernel.org>, Andrew Lunn <andrew@lunn.ch>
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On Mon, Mar 22, 2021 at 6:03 PM Matteo Croce <mcroce@linux.microsoft.com> wrote:
>
> From: Ilias Apalodimas <ilias.apalodimas@linaro.org>
>
> During skb_release_data() intercept the packet and if it's a buffer
> coming from our page_pool API recycle it back to the pool for further
> usage.
> To achieve that we introduce a bit in struct sk_buff (pp_recycle:1) and
> store the xdp_mem_info in page->private. The SKB bit is needed since
> page->private is used by skb_copy_ubufs, so we can't rely solely on
> page->private to trigger recycling.
>
> The driver has to take care of the sync operations on it's own
> during the buffer recycling since the buffer is never unmapped.
>
> In order to enable recycling the driver must call skb_mark_for_recycle()
> to store the information we need for recycling in page->private and
> enabling the recycling bit
>
> Storing the information in page->private allows us to recycle both SKBs
> and their fragments
>
> Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> Signed-off-by: Matteo Croce <mcroce@microsoft.com>
> ---

Hi, the patch title really should be:

page_pool: DMA handling and frame recycling via SKBs

As in the previous RFC.
Sorry,
-- 
per aspera ad upstream