Re: [PATCH RESEND net-next] wwan: core: Support slicing in port TX flow of WWAN subsystem

From: Simon Horman <simon.horman@corigine.com>
To: haozhe.chang@mediatek.com
Cc: M Chetan Kumar <m.chetan.kumar@intel.com>,
	Intel Corporation <linuxwwan@intel.com>,
	Loic Poulain <loic.poulain@linaro.org>,
	Sergey Ryazanov <ryazanov.s.a@gmail.com>,
	Johannes Berg <johannes@sipsolutions.net>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Stephan Gerhold <stephan@gerhold.net>,
	Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>,
	Chiranjeevi Rapolu <chiranjeevi.rapolu@linux.intel.com>,
	Liu Haijun <haijun.liu@mediatek.com>,
	Ricardo Martinez <ricardo.martinez@linux.intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Oliver Neukum <oneukum@suse.com>,
	Shang XiaoJing <shangxiaojing@huawei.com>,
	"open list:INTEL WWAN IOSM DRIVER" <netdev@vger.kernel.org>,
	open list <linux-kernel@vger.kernel.org>,
	"open list:REMOTE PROCESSOR MESSAGING (RPMSG) WWAN CONTROL..."
	<linux-remoteproc@vger.kernel.org>,
	"open list:USB SUBSYSTEM" <linux-usb@vger.kernel.org>,
	"moderated list:ARM/Mediatek SoC support"
	<linux-arm-kernel@lists.infradead.org>,
	"moderated list:ARM/Mediatek SoC support"
	<linux-mediatek@lists.infradead.org>,
	lambert.wang@mediatek.com, xiayu.zhang@mediatek.com,
	hua.yang@mediatek.com
Subject: Re: [PATCH RESEND net-next] wwan: core: Support slicing in port TX flow of WWAN subsystem
Date: Tue, 7 Mar 2023 16:37:31 +0100	[thread overview]
Message-ID: <ZAdaO0w2u8AL27un@corigine.com> (raw)
In-Reply-To: <20230307081113.67746-1-haozhe.chang@mediatek.com>

On Tue, Mar 07, 2023 at 04:11:04PM +0800, 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>
> 
> ---
> Changes in v2
>   -send fragments to device driver by skb frag_list.
> 
> Changes in v3
>   -move frag_len and headroom_len setting to wwan_create_port.
> 
> Changes in v4
>   -change unreadable parameters to macro definition.
> 
> Changes in v5
>   -optimize comments for WWAN_NO_HEADROOM, WWAN_NO_FRAGMENT.
> 
> Changes in v6
>   -add reviewer to patch commit.

Thanks for resending.

Perhaps I am missing something terribly obvious,
but this patch does not seem to apply against net-next (anymore?).

I think it would be best to rebase and post a v7.

Also, the version was missing from the patch subject (but present in v5).