[dpdk-users] DPDK: MPLS packet processing

[Raslan Darawsheh]

++,

Hi Raktim,

> -----Original Message-----
> From: users <users-bounces at dpdk.org> On Behalf Of raktim bhatt
> Sent: Saturday, January 16, 2021 10:46 AM
> To: users at dpdk.org
> Subject: [dpdk-users] DPDK: MPLS packet processing
> 
> 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?
> 
> My Port configuration is
> 
> 
> const struct rte_eth_conf default_port_conf = {
> 
>     .rxmode = {
> 
>             .hw_vlan_strip  = 0,    /* VLAN strip enabled. */
> 
>             .header_split   = 0,    /* Header Split disabled. */
> 
>             .hw_ip_checksum = 0,    /* IP checksum offload disabled. */
> 
>             .hw_strip_crc   = 0,    /* CRC stripping by hardware disabled.
> */
> 
>     },
> 
>     .rx_adv_conf = {
> 
>             .rss_conf = {
> 
>                     .rss_key = NULL,
> 
>                     .rss_key_len = 0,
> 
>                     .rss_hf = ETH_RSS_IP,
> 
>             },
> 
>     } };
> 
> _______________________
> 
> 
> Thanks and Regards
> 
> Raktim Bhatt