[dpdk-users] DPDK: MPLS packet processing

[Raslan Darawsheh]

> -----Original Message-----
> From: Thomas Monjalon <thomas at monjalon.net>
> Sent: Monday, January 18, 2021 12:08 PM
> To: raktim bhatt <rocky.cair at gmail.com>; Raslan Darawsheh
> <rasland at nvidia.com>
> Cc: users at dpdk.org; Slava Ovsiienko <viacheslavo at nvidia.com>; Asaf Penso
> <asafp at nvidia.com>
> Subject: Re: [dpdk-users] DPDK: MPLS packet processing
> 
> 18/01/2021 09:46, Raslan Darawsheh:
> > From: raktim bhatt
> >
> > > Hi All,
> > >
> > > I am trying to build a multi-RX-queue dpdk program, using RSS to split the
> > > incoming traffic into RX queues on a single port. Mellanox ConnectX-5
> and
> > > DPDK Version 19.11 is used for this purpose. It works fine when I use IP
> > > over Ethernet packets as input. However when the packet contains IP
> over
> > > MPLS over Ethernet, RSS does not seem to work. As a result, all packets
> > > belonging to various flows (with different src & dst IPs, ports over MPLS)
> > > are all sent into the same RX queue.
> > >
> > >
> > > My queries are
> > >
> > > 1. Is there any parameter/techniques in DPDK to distribute MPLS packets
> to
> > > multiple RX queues?
> > >
> > I've tried it over my setup with testpmd:
> > ./build/app/dpdk-testpmd -n 4 -w 0000:08:00.0 -- --mbcache=512 -i --nb-
> cores=27 --rxq=4 --txq=4 --rss-ip
> > testpmd> set verbose 1
> > testpmd> start
> >
> > then tried to send two MPLS packets with different src IP:
> > packet1 =  Ether()/MPLS()/IP(src='1.1.1.1')
> > packet2 =  Ether()/MPLS()/IP(src='1.1.1.2')
> >
> > and I see that both packets are being spread over the queues, see the
> bellow testpmd dump output:
> > testpmd> port 0/queue 3: received 1 packets
> >   src=00:00:00:00:00:00 - dst=FF:FF:FF:FF:FF:FF - type=0x8847 - length=60 -
> nb_segs=1 - RSS hash=0x43781943 - RSS queue=0x3 - hw ptype: L2_ETHER
> L3_IPV4_EXT_UNKNOWN L4_NONFRAG  - sw ptype: L2_ETHER  - l2_len=14 -
> Receive queue=0x3
> >   ol_flags: PKT_RX_RSS_HASH PKT_RX_L4_CKSUM_UNKNOWN
> PKT_RX_IP_CKSUM_GOOD PKT_RX_OUTER_L4_CKSUM_UNKNOWN
> > port 0/queue 1: received 1 packets
> >   src=00:00:00:00:00:00 - dst=FF:FF:FF:FF:FF:FF - type=0x8847 - length=60 -
> nb_segs=1 - RSS hash=0xb8631e05 - RSS queue=0x1 - hw ptype: L2_ETHER
> L3_IPV4_EXT_UNKNOWN L4_NONFRAG  - sw ptype: L2_ETHER  - l2_len=14 -
> Receive queue=0x1
> >   ol_flags: PKT_RX_RSS_HASH PKT_RX_L4_CKSUM_UNKNOWN
> PKT_RX_IP_CKSUM_GOOD PKT_RX_OUTER_L4_CKSUM_UNKNOWN
> >
> > first packet was received on queue 3 and the second one was received
> over queue 1,
> > by the way, this is with both 19.11.0 and v19.11.6
> >
> > > 2. Is there any way to strip off MPLS tags (between Eth and IP) in
> > > hardware, something like hw_vlan_strip?
> > >
> > For this I'm not sure we have such thing in dpdk maybe Thomas can confirm
> this here?
> 
> Look for "POP_MPLS" in rte_flow.
> 
Thanks, for pointing to it, I've just noticed it. 
But unfortunately, we don't have support for this action in MLX5 PMD.

Kindest regards
Raslan Darawsheh