From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pascal Mazon <pascal.mazon@6wind.com>
Subject: Re: [PATCH] net/tap: add Rx/Tx checksum offload support
Date: Tue, 23 May 2017 08:51:43 +0200
Message-ID: <20170523085143.73bb3f50@paques.dev.6wind.com>
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To: Ferruh Yigit <ferruh.yigit@intel.com>
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Hi Ferruh,

I'm not sure it would actually be so useful for other vPMDs.
Virtio and vmxnet3 for instance have their own mechanisms for handling
offloading.

Software offload is especially relevant for tap as packets may come from
anywhere (from another process, from a remote netdevice), and the
application would be interested in knowing how good the packet is.

At first, I'd rather keep the code as-is in tap, which is generic enough
to be easily moved later when actual need arise.

Best regards,

Pascal

On Mon, 22 May 2017 13:24:41 +0100
Ferruh Yigit <ferruh.yigit@intel.com> wrote:

> Hi Pascal,
> 
> On 5/22/2017 12:20 PM, Pascal Mazon wrote:
> > This patch adds basic offloading support, widely expected in a PMD.
> > 
> > Verify IPv4 and UDP/TCP checksums upon packet reception, and set
> > ol_flags accordingly.
> > 
> > On Tx, set IPv4 and UDP/TCP checksums when required, considering
> > ol_flags.
> 
> These are not specific to tap and can be used by any virtual PMD, right?
> 
> What do you think moving implementation into more generic location (I
> don't know where right now) and use from there, and other PMDs also can
> benefit from these?
> 
> Thanks,
> ferruh
> 
> > 
> > Signed-off-by: Pascal Mazon <pascal.mazon@6wind.com>
> 
> <...>
>