On Thu, 18 May 2017 17:41:48 +0200 Jesper Dangaard Brouer <bro...@redhat.com> wrote:
> Introducing a new XDP feature and associated bpf helper bpf_xdp_rxhash. > > The rxhash and type allow filtering on packets without touching > packet memory. The performance difference on my system with a > 100 Gbit/s mlx5 NIC is 12Mpps to 19Mpps. The XDP/bpf program I use (called xdp_rxhash) for testing this feature is available via my github repo here: https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/samples/bpf/xdp_rxhash_kern.c https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/samples/bpf/xdp_rxhash_user.c The cmdline output looks like: $ sudo ./xdp_rxhash --dev mlx5p2 --sec 2 --notouch xdp-action pps pps-human-readable mem XDP_ABORTED 19694682 19,694,682 2.000205 no_touch XDP_DROP 0 0 2.000205 no_touch XDP_PASS 10 10 2.000205 no_touch XDP_TX 0 0 2.000205 no_touch rx_total 19694701 19,694,701 2.000205 no_touch hash_type:L3 pps pps-human-readable sample-period Unknown 0 0 2.000205 IPv4 19694725 19,694,725 2.000205 IPv6 0 0 2.000205 hash_type:L4 pps pps-human-readable sample-period Unknown 10 10 2.000205 TCP 0 0 2.000205 UDP 19694697 19,694,697 2.000205 ^CInterrupted: Removing XDP program on ifindex:5 device:mlx5p2 The 10 pps XDP_PASS is a ping command I rand at the same time. Notice how these ping-ICMP packets were categorized as L4=Unknown and L3=IPv4. The L4 categorization is usually UDP or TCP, but looking at driver-code it seems some HW support detecting other L4 types, like ICMP, SCTP, etc. $ sudo taskset -c 4 ping -i 0.1 -c 10000 198.18.100.1 -c 100 -q PING 198.18.100.1 (198.18.100.1) 56(84) bytes of data. --- 198.18.100.1 ping statistics --- 100 packets transmitted, 100 received, 0% packet loss, time 10294ms rtt min/avg/max/mdev = 0.010/0.071/0.113/0.043 ms p.s. xdp-newbies can via this commit find the links back to the netdev kernel RFC patches/mails: https://github.com/netoptimizer/prototype-kernel/commit/9647e1b563970 -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer
