From owner-freebsd-net@freebsd.org  Mon Jun 29 17:55:23 2015
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Date: Mon, 29 Jun 2015 20:55:19 +0300
From: Slawa Olhovchenkov <slw@zxy.spb.ru>
To: Adrian Chadd <adrian.chadd@gmail.com>
Cc: Navdeep Parhar <np@freebsd.org>, FreeBSD Net <freebsd-net@freebsd.org>
Subject: Re: netmap custom RSS and custom packet info
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On Mon, Jun 29, 2015 at 10:41:39AM -0700, Adrian Chadd wrote:

> Hi,
> 
> PPPoE will not be hashed according to RSS on the 1g/10g (igb, ixgbe)
> intel hardware. you're going to have to figure out some other method
> for traffic redistribution.

I propose ephemeral but permanent NETMAP RX pipe with redistribution
function from user-loadable kernel module.

Hardware RxRing(i) => loadable hash => user-visible RxRing(j).

As I perceive overhead is packet-parsing and hash computation +
swaping of slot indexes (zero-copying between hardware ring and
user-visible ring).

In other (Tx) direction user-visible direct mapped to hardware ring.

> If it's inside GRE, then it's IPv4/IPv6 and thus yes, you can do
> symmetric hashing. But if it's raw pppoe coming in, you're SoL.

This is will be only hashed tunnel IPs, yes?
Not sessions inside tunnel.