Hi Jianfeng,
>
> Hi,
>
> On 7/18/2016 7:56 PM, Zhe Tao wrote:
> > Problem:
> > When using the TSO + VXLAN feature in i40e, the outer UDP length
> > fields in the multiple UDP segments which are TSOed by the i40e will
> > have a wrong value.
> >
> > Fix this problem by adding the tunnel type field in the i40e
> > descriptor which was missed before.
> >
> > Fixes: 77b8301733c3 ("i40e: VXLAN Tx checksum offload")
> >
> > Signed-off-by: Zhe Tao <zhe.tao at intel.com>
> > ---
> > v2: edited the comments
> > v3: added external IP offload flag when TSO is enabled for tunnelling
> > packets
> >
> > app/test-pmd/csumonly.c | 29 +++++++++++++++++++++--------
> > drivers/net/i40e/i40e_rxtx.c | 12 +++++++++---
> > lib/librte_mbuf/rte_mbuf.h | 16 +++++++++++++++-
> > 3 files changed, 45 insertions(+), 12 deletions(-)
> >
> ...
> > diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
> > index 15e3a10..90812ea 100644
> > --- a/lib/librte_mbuf/rte_mbuf.h
> > +++ b/lib/librte_mbuf/rte_mbuf.h
> > @@ -133,6 +133,17 @@ extern "C" {
> > /* add new TX flags here */
> >
> > /**
> > + * Bits 45:48 used for the tunnel type.
> > + * When doing Tx offload like TSO or checksum, the HW needs to
> > +configure the
> > + * tunnel type into the HW descriptors.
> > + */
> > +#define PKT_TX_TUNNEL_VXLAN (1ULL << 45)
> > +#define PKT_TX_TUNNEL_GRE (2ULL << 45)
> > +#define PKT_TX_TUNNEL_IPIP (3ULL << 45)
> > +/* add new TX TUNNEL type here */
> > +#define PKT_TX_TUNNEL_MASK (0xFULL << 45)
> > +
>
> Above flag bits are added so that i40e driver can tell tunnel type of this
> packet (udp or gre or ipip), just interested to know how about just do
> a simple analysis like below without introducing these flags?
>
> if outer_ether.proto == ipv4
> l4_proto = ipv4_hdr->next_proto;
> else outer_ether.proto == ipv6
> l4_proto = ipv6_hdr->next_proto;
>
> switch (l4_proto)
> case ipv4:
> case ipv6:
> tunnel_type = ipip;
> break;
> case udp:
> tunnel_type = udp;
> break;
> case gre:
> tunnel_type = gre;
> break;
> default:
> error;
Right now none of our PMDs reads/writes actual packet data,
and I think it is better to keep it that way.
It is an upper layer responsibility to specify which offload
needs to be enabled and provide necessary information.
Konstantin
>
> Thanks,
> Jianfeng
>
>
> > +/**
> > * Second VLAN insertion (QinQ) flag.
> > */
> > #define PKT_TX_QINQ_PKT (1ULL << 49) /**< TX packet with double VLAN
> > inserted. */
> > @@ -867,7 +878,10 @@ struct rte_mbuf {
> > union {
> > uint64_t tx_offload; /**< combined for easy fetch */
> > struct {
> > - uint64_t l2_len:7; /**< L2 (MAC) Header Length. */
> > + uint64_t l2_len:7;
> > + /**< L2 (MAC) Header Length if it isn't a tunneling pkt.
> > + * for tunnel it is outer L4 len+tunnel len+inner L2 len
> > + */
> > uint64_t l3_len:9; /**< L3 (IP) Header Length. */
> > uint64_t l4_len:8; /**< L4 (TCP/UDP) Header Length. */
> > uint64_t tso_segsz:16; /**< TCP TSO segment size */
