Re: [PATCH v5] wwan: core: Support slicing in port TX flow of WWAN subsystem

From: Loic Poulain <loic.poulain@linaro.org>
To: "Haozhe Chang (常浩哲)" <Haozhe.Chang@mediatek.com>
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Subject: Re: [PATCH v5] wwan: core: Support slicing in port TX flow of WWAN subsystem
Date: Wed, 14 Dec 2022 10:10:54 +0100	[thread overview]
Message-ID: <CAMZdPi8NOfMn99yy043oYGrO1=UrnhhRvpZq-zWe4BfiU_08NA@mail.gmail.com> (raw)
In-Reply-To: <54c37c8f8eb7f35e4bb983b9104bd232758bae7b.camel@mediatek.com>

> On Thu, 2022-12-01 at 10:56 +0100, Loic Poulain wrote:
> > On Thu, 24 Nov 2022 at 08:47, <haozhe.chang@mediatek.com> wrote:
> > >
> > > From: haozhe chang <haozhe.chang@mediatek.com>
> > >
> > > wwan_port_fops_write inputs the SKB parameter to the TX callback of
> > > the WWAN device driver. However, the WWAN device (e.g., t7xx) may
> > > have an MTU less than the size of SKB, causing the TX buffer to be
> > > sliced and copied once more in the WWAN device driver.
> > >
> > > This patch implements the slicing in the WWAN subsystem and gives
> > > the WWAN devices driver the option to slice(by frag_len) or not. By
> > > doing so, the additional memory copy is reduced.
> > >
> > > Meanwhile, this patch gives WWAN devices driver the option to
> > > reserve
> > > headroom in fragments for the device-specific metadata.
> > >
> > > Signed-off-by: haozhe chang <haozhe.chang@mediatek.com>
> >
> > Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
>
> I have submitted patch V6 to add a reviewer, do you have any other
> suggestions about the patch?

You normally don't need to resubmit a version just for adding review
tags, as it is well tracked. You can see status of netdev changes from
patchwork:
https://patchwork.kernel.org/project/netdevbpf/list/?series=&submitter=207580&state=*&q=&archive=both&delegate=

Regarding this change you should however resubmit for the net-next
tree with appropriate subject since it is not a bug fix:
https://www.kernel.org/doc/html/latest/process/maintainer-netdev.html?highlight=netdev#how-do-i-indicate-which-tree-net-vs-net-next-my-patch-should-be-in

Then it should be picked by netdev maintainer(s). But note that we're
currently in the Linux 6.2 merge window, so merging for net-next can
be delayed until the mainline merge window is closed (and net-next
open):
https://www.kernel.org/doc/html/latest/process/maintainer-netdev.html?highlight=netdev#how-often-do-changes-from-these-trees-make-it-to-the-mainline-linus-tree

Regards,
Loic