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From: Shakeel Butt <shakeelb@google.com>
Date: Sat, 16 Dec 2023 11:46:54 -0800
Message-ID: <CALvZod5myy2SvuCMNmqjjYeNONqSArV+8y8mrkfnNeog8WLjng@mail.gmail.com>
Subject: Re: [RFC PATCH net-next v1 4/4] net: page_pool: use netmem_t instead
 of struct page in API
To: Jakub Kicinski <kuba@kernel.org>
Cc: Mina Almasry <almasrymina@google.com>, Yunsheng Lin <linyunsheng@huawei.com>, 
	linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, 
	Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>, 
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On Fri, Dec 15, 2023 at 7:01=E2=80=AFPM Jakub Kicinski <kuba@kernel.org> wr=
ote:
>
> On Fri, 15 Dec 2023 02:11:14 +0000 Shakeel Butt wrote:
> > > From my POV it has to be the first one. We want to abstract the memor=
y
> > > type from the drivers as much as possible, not introduce N new memory
> > > types and ask the driver to implement new code for each of them
> > > separately.
> >
> > Agree with Mina's point. Let's aim to decouple memory types from
> > drivers.
>
> What does "decouple" mean? Drivers should never convert netmem
> to pages. Either a path in the driver can deal with netmem,
> i.e. never touch the payload, or it needs pages.

"Decouple" might not be the right word. What I wanted to say was to
avoid too much specialization such that we have to have a new API for
every new fancy thing.

>
> Perhaps we should aim to not export netmem_to_page(),
> prevent modules from accessing it directly.

+1.