Subject: Re: [RFC PATCH 0/2] rx zero copy interface for af_packet

From: John Fastabend <[email-masked]>
Date: Tue, 31 Jan 2017 21:09:07 -0800

On 17-01-31 11:39 AM, tndave wrote:
> 
> 
> On 01/27/2017 01:33 PM, John Fastabend wrote:
>> This is an experimental implementation of rx zero copy for af_packet.
>> Its a bit rough and likely has errors but the plan is to clean it up
>> over the next few months.
>>
>> And seeing I said I would post it in another thread a few days back
>> here it is.
> 
> This sounds good (believe me I have been thinking along the lines :)
> From driver Rx side, we always premap RX buffers so best to map them to
> shmem for PF_PACKET sockets.
> Also, I like the idea that user can put selected queue (may be queues in
> future?) to PF_PACKET mode keeping rest of the queues as it is.
> Zero copy and removing skb setup & processing overhead on RX certainly
> makes things faster and help latency. Zero copy is good on Tx however
> without skb should we figure out how to use segmentation and checksum offloading
> features of HW. Can this be considered in tpacket V4 hdr!
> 

Yes, I'll try to create another RFC in a week or two. Thanks.

> -Tushar