Currently, the dpdk-vhost side in ovs doesn't support tcp/udp tx cksum. So L4 packets's cksum were calculated in VM side but performance is not good. Implementing tcp/udp tx cksum in ovs-dpdk side improves throughput and makes virtio-net frontend-driver support NETIF_F_SG as well
Signed-off-by: Zhenyu Gao <[email protected]> --- Here is some performance number: Setup: qperf client +---------+ | VM | +---------+ | | qperf server +--------------+ +------------+ | vswitch+dpdk | | bare-metal | +--------------+ +------------+ | | | | pNic---------PhysicalSwitch---- do cksum in ovs-dpdk: Applied this patch and execute 'ethtool -K eth0 tx on' in VM side. It offload cksum job to ovs-dpdk side. do cksum in VM: Applied this patch and execute 'ethtool -K eth0 tx off' in VM side. VM calculate cksum for tcp/udp packets. We can see huge improvment in TCP throughput if we leverage ovs-dpdk cksum. [root@localhost ~]# qperf -t 10 -oo msg_size:1:64K:*2 host-qperf-server01 tcp_bw tcp_lat udp_bw udp_lat do cksum in ovs-dpdk do cksum in VM without this patch tcp_bw: bw = 2.05 MB/sec bw = 1.92 MB/sec bw = 1.95 MB/sec tcp_bw: bw = 3.9 MB/sec bw = 3.99 MB/sec bw = 3.98 MB/sec tcp_bw: bw = 8.09 MB/sec bw = 7.82 MB/sec bw = 8.19 MB/sec tcp_bw: bw = 14.9 MB/sec bw = 14.8 MB/sec bw = 15.7 MB/sec tcp_bw: bw = 27.7 MB/sec bw = 28 MB/sec bw = 29.7 MB/sec tcp_bw: bw = 51.2 MB/sec bw = 50.9 MB/sec bw = 54.9 MB/sec tcp_bw: bw = 86.7 MB/sec bw = 86.8 MB/sec bw = 95.1 MB/sec tcp_bw: bw = 149 MB/sec bw = 160 MB/sec bw = 149 MB/sec tcp_bw: bw = 211 MB/sec bw = 205 MB/sec bw = 216 MB/sec tcp_bw: bw = 271 MB/sec bw = 254 MB/sec bw = 275 MB/sec tcp_bw: bw = 326 MB/sec bw = 303 MB/sec bw = 321 MB/sec tcp_bw: bw = 407 MB/sec bw = 359 MB/sec bw = 361 MB/sec tcp_bw: bw = 816 MB/sec bw = 512 MB/sec bw = 419 MB/sec tcp_bw: bw = 840 MB/sec bw = 756 MB/sec bw = 457 MB/sec tcp_bw: bw = 1.07 GB/sec bw = 880 MB/sec bw = 480 MB/sec tcp_bw: bw = 1.17 GB/sec bw = 1.01 GB/sec bw = 488 MB/sec tcp_bw: bw = 1.17 GB/sec bw = 1.11 GB/sec bw = 483 MB/sec tcp_lat: latency = 29 us latency = 29.2 us latency = 29.6 us tcp_lat: latency = 28.9 us latency = 29.3 us latency = 29.5 us tcp_lat: latency = 29 us latency = 29.3 us latency = 29.6 us tcp_lat: latency = 29 us latency = 29.4 us latency = 29.5 us tcp_lat: latency = 29 us latency = 29.2 us latency = 29.6 us tcp_lat: latency = 29.1 us latency = 29.3 us latency = 29.7 us tcp_lat: latency = 29.4 us latency = 29.6 us latency = 30 us tcp_lat: latency = 29.8 us latency = 30.1 us latency = 30.2 us tcp_lat: latency = 30.9 us latency = 30.9 us latency = 31 us tcp_lat: latency = 46.9 us latency = 46.2 us latency = 32.2 us tcp_lat: latency = 51.5 us latency = 52.6 us latency = 34.5 us tcp_lat: latency = 43.9 us latency = 43.8 us latency = 43.6 us tcp_lat: latency = 47.6 us latency = 48 us latency = 48.1 us tcp_lat: latency = 77.7 us latency = 78.8 us latency = 78.8 us tcp_lat: latency = 82.8 us latency = 82.3 us latency = 116 us tcp_lat: latency = 94.8 us latency = 94.2 us latency = 134 us tcp_lat: latency = 167 us latency = 197 us latency = 172 us udp_bw: send_bw = 418 KB/sec send_bw = 413 KB/sec send_bw = 403 KB/sec recv_bw = 410 KB/sec recv_bw = 412 KB/sec recv_bw = 400 KB/sec udp_bw: send_bw = 831 KB/sec send_bw = 825 KB/sec send_bw = 810 KB/sec recv_bw = 828 KB/sec recv_bw = 816 KB/sec recv_bw = 807 KB/sec udp_bw: send_bw = 1.67 MB/sec send_bw = 1.65 MB/sec send_bw = 1.63 MB/sec recv_bw = 1.64 MB/sec recv_bw = 1.62 MB/sec recv_bw = 1.63 MB/sec udp_bw: send_bw = 3.36 MB/sec send_bw = 3.29 MB/sec send_bw = 3.26 MB/sec recv_bw = 3.29 MB/sec recv_bw = 3.25 MB/sec recv_bw = 2.82 MB/sec udp_bw: send_bw = 6.72 MB/sec send_bw = 6.61 MB/sec send_bw = 6.45 MB/sec recv_bw = 6.54 MB/sec recv_bw = 6.59 MB/sec recv_bw = 6.45 MB/sec udp_bw: send_bw = 13.4 MB/sec send_bw = 13.2 MB/sec send_bw = 13 MB/sec recv_bw = 13.1 MB/sec recv_bw = 13.1 MB/sec recv_bw = 13 MB/sec udp_bw: send_bw = 26.8 MB/sec send_bw = 26.4 MB/sec send_bw = 25.9 MB/sec recv_bw = 26.4 MB/sec recv_bw = 26.2 MB/sec recv_bw = 25.7 MB/sec udp_bw: send_bw = 53.4 MB/sec send_bw = 52.5 MB/sec send_bw = 52 MB/sec recv_bw = 48.4 MB/sec recv_bw = 51.8 MB/sec recv_bw = 51.2 MB/sec udp_bw: send_bw = 106 MB/sec send_bw = 104 MB/sec send_bw = 103 MB/sec recv_bw = 98.9 MB/sec recv_bw = 93.2 MB/sec recv_bw = 100 MB/sec udp_bw: send_bw = 213 MB/sec send_bw = 206 MB/sec send_bw = 205 MB/sec recv_bw = 197 MB/sec recv_bw = 196 MB/sec recv_bw = 202 MB/sec udp_bw: send_bw = 417 MB/sec send_bw = 405 MB/sec send_bw = 401 MB/sec recv_bw = 400 MB/sec recv_bw = 333 MB/sec recv_bw = 358 MB/sec udp_bw: send_bw = 556 MB/sec send_bw = 552 MB/sec send_bw = 557 MB/sec recv_bw = 361 MB/sec recv_bw = 365 MB/sec recv_bw = 362 MB/sec udp_bw: send_bw = 865 MB/sec send_bw = 866 MB/sec send_bw = 863 MB/sec recv_bw = 564 MB/sec recv_bw = 573 MB/sec recv_bw = 584 MB/sec udp_bw: send_bw = 1.05 GB/sec send_bw = 1.09 GB/sec send_bw = 1.08 GB/sec recv_bw = 789 MB/sec recv_bw = 732 MB/sec recv_bw = 793 MB/sec udp_bw: send_bw = 1.18 GB/sec send_bw = 1.23 GB/sec send_bw = 1.19 GB/sec recv_bw = 658 MB/sec recv_bw = 788 MB/sec recv_bw = 673 MB/sec udp_bw: send_bw = 1.3 GB/sec send_bw = 1.3 GB/sec send_bw = 1.3 GB/sec recv_bw = 659 MB/sec recv_bw = 763 MB/sec recv_bw = 762 MB/sec udp_bw: send_bw = 0 bytes/sec send_bw = 0 bytes/sec send_bw = 0 bytes/sec recv_bw = 0 bytes/sec recv_bw = 0 bytes/sec recv_bw = 0 bytes/sec udp_lat: latency = 26.7 us latency = 26.5 us latency = 26.4 us udp_lat: latency = 26.7 us latency = 26.5 us latency = 26.3 us udp_lat: latency = 26.7 us latency = 26.7 us latency = 26.3 us udp_lat: latency = 26.7 us latency = 26.6 us latency = 26.3 us udp_lat: latency = 26.7 us latency = 26.7 us latency = 26.7 us udp_lat: latency = 27 us latency = 26.7 us latency = 26.6 us udp_lat: latency = 27 us latency = 26.9 us latency = 26.7 us udp_lat: latency = 27.6 us latency = 27.4 us latency = 27.3 us udp_lat: latency = 28.1 us latency = 28 us latency = 28 us udp_lat: latency = 29.4 us latency = 29.2 us latency = 29.2 us udp_lat: latency = 31 us latency = 31 us latency = 30.8 us udp_lat: latency = 41.4 us latency = 41.4 us latency = 41.3 us udp_lat: latency = 41.6 us latency = 41.5 us latency = 41.5 us udp_lat: latency = 64.9 us latency = 65 us latency = 65 us udp_lat: latency = 72.3 us latency = 72 us latency = 72 us udp_lat: latency = 121 us latency = 122 us latency = 122 us udp_lat: latency = 0 ns latency = 0 ns latency = 0 ns lib/netdev-dpdk.c | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 77 insertions(+), 4 deletions(-) diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c index 1d82bca..cdaf21a 100644 --- a/lib/netdev-dpdk.c +++ b/lib/netdev-dpdk.c @@ -31,6 +31,7 @@ #include <rte_errno.h> #include <rte_eth_ring.h> #include <rte_ethdev.h> +#include <rte_ip.h> #include <rte_malloc.h> #include <rte_mbuf.h> #include <rte_meter.h> @@ -991,8 +992,7 @@ netdev_dpdk_vhost_construct(struct netdev *netdev) err = rte_vhost_driver_disable_features(dev->vhost_id, 1ULL << VIRTIO_NET_F_HOST_TSO4 - | 1ULL << VIRTIO_NET_F_HOST_TSO6 - | 1ULL << VIRTIO_NET_F_CSUM); + | 1ULL << VIRTIO_NET_F_HOST_TSO6); if (err) { VLOG_ERR("rte_vhost_driver_disable_features failed for vhost user " "port: %s\n", name); @@ -1454,6 +1454,78 @@ netdev_dpdk_rxq_dealloc(struct netdev_rxq *rxq) rte_free(rx); } +static inline void +netdev_refill_l4_cksum(const char *data, struct dp_packet *pkt, + uint8_t l4_proto, bool is_ipv4) +{ + void *l3hdr = (void *)(data + pkt->mbuf.l2_len); + + if (l4_proto == IPPROTO_TCP) { + struct tcp_header *tcp_hdr = (struct tcp_header *)(data + + pkt->mbuf.l2_len + pkt->mbuf.l3_len); + + tcp_hdr->tcp_csum = 0; + if (is_ipv4) { + tcp_hdr->tcp_csum = rte_ipv4_udptcp_cksum(l3hdr, tcp_hdr); + } else { + tcp_hdr->tcp_csum = rte_ipv6_udptcp_cksum(l3hdr, tcp_hdr); + } + } else if (l4_proto == IPPROTO_UDP) { + struct udp_header *udp_hdr = (struct udp_header *)(data + + pkt->mbuf.l2_len + pkt->mbuf.l3_len); + /* do not recalculate udp cksum if it was 0 */ + if (udp_hdr->udp_csum != 0) { + udp_hdr->udp_csum = 0; + if (is_ipv4) { + /*do not calculate udp cksum if it was a fragment IP*/ + if (IP_IS_FRAGMENT(((struct ipv4_hdr *)l3hdr)-> + fragment_offset)) { + return; + } + + udp_hdr->udp_csum = rte_ipv4_udptcp_cksum(l3hdr, udp_hdr); + } else { + udp_hdr->udp_csum = rte_ipv6_udptcp_cksum(l3hdr, udp_hdr); + } + } + } + + pkt->mbuf.ol_flags &= ~PKT_TX_L4_MASK; +} + +static inline void +netdev_dpdk_vhost_tx_csum(struct dp_packet **pkts, int pkt_cnt) +{ + int i; + + for (i = 0; i < pkt_cnt; i++) { + ovs_be16 dl_type; + struct dp_packet *pkt = (struct dp_packet *)pkts[i]; + const char *data = dp_packet_data(pkt); + void *l3hdr = (char *)(data + pkt->mbuf.l2_len); + + if (!(pkt->mbuf.ol_flags & PKT_TX_L4_MASK)) { + // DPDK vhost-user tags PKT_TX_L4_MASK if a L4 packet need cksum + continue; + } + + if (OVS_UNLIKELY(pkt->mbuf.l2_len == 0 || pkt->mbuf.l3_len == 0)) { + continue; + } + + dl_type = *(ovs_be16 *)(data + pkt->mbuf.l2_len - 2); + if (dl_type == htons(ETH_TYPE_IP)) { + netdev_refill_l4_cksum(data, pkt, + ((struct ipv4_hdr *)l3hdr)->next_proto_id, + true); + } else if (dl_type == htons(ETH_TYPE_IPV6)) { + netdev_refill_l4_cksum(data, pkt, + ((struct ipv6_hdr *)l3hdr)->proto, + false); + } + } +} + /* Tries to transmit 'pkts' to txq 'qid' of device 'dev'. Takes ownership of * 'pkts', even in case of failure. * @@ -1644,6 +1716,8 @@ netdev_dpdk_vhost_rxq_recv(struct netdev_rxq *rxq, rte_spinlock_unlock(&dev->stats_lock); batch->count = (int) nb_rx; + netdev_dpdk_vhost_tx_csum(batch->packets, batch->count); + return 0; } @@ -3285,8 +3359,7 @@ netdev_dpdk_vhost_client_reconfigure(struct netdev *netdev) err = rte_vhost_driver_disable_features(dev->vhost_id, 1ULL << VIRTIO_NET_F_HOST_TSO4 - | 1ULL << VIRTIO_NET_F_HOST_TSO6 - | 1ULL << VIRTIO_NET_F_CSUM); + | 1ULL << VIRTIO_NET_F_HOST_TSO6); if (err) { VLOG_ERR("rte_vhost_driver_disable_features failed for vhost user " "client port: %s\n", dev->up.name); -- 1.8.3.1 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
