From 3a928a262c1c1c63c929ebe40c181376afbcfe41 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 25 Dec 2017 14:43:58 +0800 Subject: [PATCH] geneve: update skb dst pmtu on tx path commit 52a589d51f1008f62569bf89e95b26221ee76690 upstream. Commit a93bf0ff4490 ("vxlan: update skb dst pmtu on tx path") has fixed a performance issue caused by the change of lower dev's mtu for vxlan. The same thing needs to be done for geneve as well. Note that geneve cannot adjust it's mtu according to lower dev's mtu when creating it. The performance is very low later when netperfing over it without fixing the mtu manually. This patch could also avoid this issue. Signed-off-by: Xin Long Signed-off-by: David S. Miller Cc: Thomas Deutschmann Cc: Eddie Chapman Signed-off-by: Greg Kroah-Hartman --- drivers/net/geneve.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index b9d8d71a6ecc..1b0fcf0b2afa 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -825,6 +825,13 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev, if (IS_ERR(rt)) return PTR_ERR(rt); + if (skb_dst(skb)) { + int mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr) - + GENEVE_BASE_HLEN - info->options_len - 14; + + skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); + } + sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true); if (geneve->collect_md) { tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb); @@ -864,6 +871,13 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev, if (IS_ERR(dst)) return PTR_ERR(dst); + if (skb_dst(skb)) { + int mtu = dst_mtu(dst) - sizeof(struct ipv6hdr) - + GENEVE_BASE_HLEN - info->options_len - 14; + + skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); + } + sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true); if (geneve->collect_md) { prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb); -- 2.20.1