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Date:   Wed, 15 Feb 2023 09:35:05 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Jamal Hadi Salim <jhs@mojatatu.com>
Cc:     davem@davemloft.net, netdev@vger.kernel.org, edumazet@google.com,
        pabeni@redhat.com, willemb@google.com, fw@strlen.de,
        saeedm@nvidia.com, leon@kernel.org, xiyou.wangcong@gmail.com,
        jiri@resnulli.us, roid@nvidia.com, ozsh@nvidia.com,
        paulb@nvidia.com
Subject: Re: [PATCH net-next 3/3] net: create and use NAPI version of
 tc_skb_ext_alloc()
Message-ID: <20230215093505.4b27c8ea@kernel.org>
In-Reply-To: <CAM0EoMnkcvHpbJY-Tqo8CngN4Y_hnYoeaYCMW+OVXcNVAbwzug@mail.gmail.com>
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        <20230215034355.481925-4-kuba@kernel.org>
        <CAM0EoMnkcvHpbJY-Tqo8CngN4Y_hnYoeaYCMW+OVXcNVAbwzug@mail.gmail.com>
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On Wed, 15 Feb 2023 11:50:55 -0500 Jamal Hadi Salim wrote:
> Dumb question: Would this work with a consumer of the metadata past
> RPS stage? didnt look closely but assumed per cpu skb_ext because of
> the napi context - which will require a per cpu pointer to fetch it
> later.

The cache is just for allocation, specifically for the case where
driver allocates the skb and it's quickly coalesced by GRO.
The lifetime of the allocated object is not changed.