| Message ID | 1505199911-21153-1-git-send-email-yanhaishuang@cmss.chinamobile.com |
|---|---|
| State | Deferred, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | [v2] geneve: Fix setting ttl value in collect metadata mode | expand |
On Tue, Sep 12, 2017 at 12:05 AM, Haishuang Yan <yanhaishuang@cmss.chinamobile.com> wrote: > Similar to vxlan/ipip tunnel, if key->tos is zero in collect metadata > mode, tos should also fallback to ip{4,6}_dst_hoplimit. > > Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> > > --- > Changes since v2: > * Make the commit message more clearer. > --- > drivers/net/geneve.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c > index f640407..d52a65f 100644 > --- a/drivers/net/geneve.c > +++ b/drivers/net/geneve.c > @@ -834,11 +834,10 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev, > 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); > - ttl = key->ttl; > } else { > tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, ip_hdr(skb), skb); > - ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst); > } > + ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst); > df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0; > This changes user API of Geneve collect-metadata mode. I do not see good reason for this. Why user can not set right TTL for the flow?
> On 2017年9月13日, at 上午7:43, Pravin Shelar <pshelar@ovn.org> wrote: > > On Tue, Sep 12, 2017 at 12:05 AM, Haishuang Yan > <yanhaishuang@cmss.chinamobile.com> wrote: >> Similar to vxlan/ipip tunnel, if key->tos is zero in collect metadata >> mode, tos should also fallback to ip{4,6}_dst_hoplimit. >> >> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> >> >> --- >> Changes since v2: >> * Make the commit message more clearer. >> --- >> drivers/net/geneve.c | 6 ++---- >> 1 file changed, 2 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c >> index f640407..d52a65f 100644 >> --- a/drivers/net/geneve.c >> +++ b/drivers/net/geneve.c >> @@ -834,11 +834,10 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev, >> 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); >> - ttl = key->ttl; >> } else { >> tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, ip_hdr(skb), skb); >> - ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst); >> } >> + ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst); >> df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0; >> > This changes user API of Geneve collect-metadata mode. I do not see > good reason for this. Why user can not set right TTL for the flow? > For example, I test this case with script samples/bpf/test_tunnel_bpf.sh, and modify samples/bpf/tcbpf2_kern.c with following patch: diff --git a/samples/bpf/tcbpf2_kern.c b/samples/bpf/tcbpf2_kern.c index 370b749..16b09ed 100644 --- a/samples/bpf/tcbpf2_kern.c +++ b/samples/bpf/tcbpf2_kern.c @@ -204,7 +204,6 @@ int _geneve_set_tunnel(struct __sk_buff *skb) key.remote_ipv4 = 0xac100164; /* 172.16.1.100 */ key.tunnel_id = 2; key.tunnel_tos = 0; - key.tunnel_ttl = 64; __builtin_memset(&gopt, 0x0, sizeof(gopt)); gopt.opt_class = 0x102; /* Open Virtual Networking (OVN) */ The user didn’t set key.tunnel_ttl and then key.tunnel_ttl is 0, so tcpdump output on veth1 would have ttl value of 0 in ip header: PING 10.1.1.100 (10.1.1.100) 56(84) bytes of data. 18:59:27.347373 82:81:85:8a:72:62 > 7e:99:fb:3b:15:73, ethertype IPv4 (0x0800), length 104: (tos 0x0, id 7386, offset 0, flags [none], proto UDP (17), length 90) 64 bytes from 10.1.1.100: icmp_seq=1 ttl=64 time=0.083 ms 172.16.1.200.57776 > 172.16.1.100.6081: [no cksum] UDP, length 62 --- 10.1.1.100 ping statistics — After my patch, tcpdump output on veth1 would have ttl value of 64 in ip header: PING 10.1.1.100 (10.1.1.100) 56(84) bytes of data. 19:12:10.870410 f2:56:13:68:e9:a9 > 8a:1e:93:dc:59:27, ethertype IPv4 (0x0800), length 104: (tos 0x0, ttl 64, id 48595, offset 0, flags [none], p roto UDP (17), length 90) 64 bytes from 10.1.1.100: icmp_seq=1 ttl=64 time=0.091 ms 172.16.1.200.57776 > 172.16.1.100.6081: [no cksum] UDP, length 62 --- 10.1.1.100 ping statistics ---
On Wed, Sep 13, 2017 at 4:15 AM, 严海双 <yanhaishuang@cmss.chinamobile.com> wrote: > > >> On 2017年9月13日, at 上午7:43, Pravin Shelar <pshelar@ovn.org> wrote: >> >> On Tue, Sep 12, 2017 at 12:05 AM, Haishuang Yan >> <yanhaishuang@cmss.chinamobile.com> wrote: >>> Similar to vxlan/ipip tunnel, if key->tos is zero in collect metadata >>> mode, tos should also fallback to ip{4,6}_dst_hoplimit. >>> >>> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> >>> >>> --- >>> Changes since v2: >>> * Make the commit message more clearer. >>> --- >>> drivers/net/geneve.c | 6 ++---- >>> 1 file changed, 2 insertions(+), 4 deletions(-) >>> >>> diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c >>> index f640407..d52a65f 100644 >>> --- a/drivers/net/geneve.c >>> +++ b/drivers/net/geneve.c >>> @@ -834,11 +834,10 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev, >>> 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); >>> - ttl = key->ttl; >>> } else { >>> tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, ip_hdr(skb), skb); >>> - ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst); >>> } >>> + ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst); >>> df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0; >>> >> This changes user API of Geneve collect-metadata mode. I do not see >> good reason for this. Why user can not set right TTL for the flow? >> > > For example, I test this case with script samples/bpf/test_tunnel_bpf.sh, > and modify samples/bpf/tcbpf2_kern.c with following patch: > But user is suppose to specify the TTL in collect-md mode for Geneve tunnel. That is the API.
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index f640407..d52a65f 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -834,11 +834,10 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev, 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); - ttl = key->ttl; } else { tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, ip_hdr(skb), skb); - ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst); } + ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst); df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0; err = geneve_build_skb(&rt->dst, skb, info, xnet, sizeof(struct iphdr)); @@ -873,12 +872,11 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev, 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); - ttl = key->ttl; } else { prio = ip_tunnel_ecn_encap(ip6_tclass(fl6.flowlabel), ip_hdr(skb), skb); - ttl = key->ttl ? : ip6_dst_hoplimit(dst); } + ttl = key->ttl ? : ip6_dst_hoplimit(dst); err = geneve_build_skb(dst, skb, info, xnet, sizeof(struct ipv6hdr)); if (unlikely(err)) return err;
Similar to vxlan/ipip tunnel, if key->tos is zero in collect metadata mode, tos should also fallback to ip{4,6}_dst_hoplimit. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> --- Changes since v2: * Make the commit message more clearer. --- drivers/net/geneve.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)