netdev - Re: [PATCH net-next v10 02/14] net: page_pool: create hooks for custom page providers

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Date: Tue, 11 Jun 2024 10:48:47 -0700
From: Mina Almasry <almasrymina@...gle.com>
To: Christoph Hellwig <hch@...radead.org>
Cc: David Ahern <dsahern@...nel.org>, Jason Gunthorpe <jgg@...pe.ca>, 
	Pavel Begunkov <asml.silence@...il.com>, David Wei <dw@...idwei.uk>, netdev@...r.kernel.org, 
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	Jeroen de Borst <jeroendb@...gle.com>, Praveen Kaligineedi <pkaligineedi@...gle.com>
Subject: Re: [PATCH net-next v10 02/14] net: page_pool: create hooks for
 custom page providers

On Mon, Jun 10, 2024 at 11:26 PM Christoph Hellwig <hch@...radead.org> wrote:
>
> On Mon, Jun 10, 2024 at 09:16:43AM -0600, David Ahern wrote:
> >
> > exactly. io_uring, page_pool, dmabuf - all kernel building blocks for
> > solutions. This why I was pushing for Mina's set not to be using the
> > name `devmem` - it is but one type of memory and with dmabuf it should
> > not matter if it is gpu or host (or something else later on - cxl?).
>
> While not really realted to the rest of the discussion I agree.
> It really is dmabuf integration now, so let's call it that?

My mental model is that the feature folks care about is the ability to
use TCP with device memory, and dmabuf is an implementation detail
that is the format that device memory is packaged in. Although not
likely given this discussion, in theory we could want to extend devmem
TCP to support p2pdma for nvme, or some other format if a new one
arises in device drivers. I also think it's more obvious to an end
user what 'devmem TCP' aims to do rather than 'dmabuf TCP' especially
if the user is not a kernel developer familiar with dmabuf.

-- 
Thanks,
Mina