> -----Original Message----- > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Olivier Matz > Sent: Friday, November 14, 2014 5:03 PM > To: dev at dpdk.org > Cc: jigsaw at gmail.com > Subject: [dpdk-dev] [PATCH v2 10/13] mbuf: generic support for TCP > segmentation offload > > Some of the NICs supported by DPDK have a possibility to accelerate TCP > traffic by using segmentation offload. The application prepares a packet > with valid TCP header with size up to 64K and deleguates the > segmentation to the NIC. > > Implement the generic part of TCP segmentation offload in rte_mbuf. It > introduces 2 new fields in rte_mbuf: l4_len (length of L4 header in bytes) > and tso_segsz (MSS of packets). > > To delegate the TCP segmentation to the hardware, the user has to: > > - set the PKT_TX_TCP_SEG flag in mbuf->ol_flags (this flag implies > PKT_TX_TCP_CKSUM) > - set PKT_TX_IP_CKSUM if it's IPv4, and set the IP checksum to 0 in > the packet > - fill the mbuf offload information: l2_len, l3_len, l4_len, tso_segsz > - calculate the pseudo header checksum without taking ip_len in account, > and set it in the TCP header, for instance by using > rte_ipv4_phdr_cksum(ip_hdr, ol_flags) > > The API is inspired from ixgbe hardware (the next commit adds the > support for ixgbe), but it seems generic enough to be used for other > hw/drivers in the future. > > This commit also reworks the way l2_len and l3_len are used in igb > and ixgbe drivers as the l2_l3_len is not available anymore in mbuf. > > Signed-off-by: Mirek Walukiewicz <miroslaw.walukiewicz at intel.com> > Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev at intel.com> > --- > app/test-pmd/testpmd.c | 2 +- > examples/ipv4_multicast/main.c | 2 +- > lib/librte_mbuf/rte_mbuf.c | 1 + > lib/librte_mbuf/rte_mbuf.h | 44 > +++++++++++++++++++++++---------------- > lib/librte_net/rte_ip.h | 39 +++++++++++++++++++++++++++------- > lib/librte_pmd_e1000/igb_rxtx.c | 11 +++++++++- > lib/librte_pmd_ixgbe/ixgbe_rxtx.c | 11 +++++++++- > 7 files changed, 81 insertions(+), 29 deletions(-) > > diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c > index 12adafa..632a993 100644 > --- a/app/test-pmd/testpmd.c > +++ b/app/test-pmd/testpmd.c > @@ -408,7 +408,7 @@ testpmd_mbuf_ctor(struct rte_mempool *mp, > mb->ol_flags = 0; > mb->data_off = RTE_PKTMBUF_HEADROOM; > mb->nb_segs = 1; > - mb->l2_l3_len = 0; > + mb->tx_offload = 0; > mb->vlan_tci = 0; > mb->hash.rss = 0; > } > diff --git a/examples/ipv4_multicast/main.c b/examples/ipv4_multicast/main.c > index 590d11a..80c5140 100644 > --- a/examples/ipv4_multicast/main.c > +++ b/examples/ipv4_multicast/main.c > @@ -302,7 +302,7 @@ mcast_out_pkt(struct rte_mbuf *pkt, int use_clone) > /* copy metadata from source packet*/ > hdr->port = pkt->port; > hdr->vlan_tci = pkt->vlan_tci; > - hdr->l2_l3_len = pkt->l2_l3_len; > + hdr->tx_offload = pkt->tx_offload; > hdr->hash = pkt->hash; > > hdr->ol_flags = pkt->ol_flags; > diff --git a/lib/librte_mbuf/rte_mbuf.c b/lib/librte_mbuf/rte_mbuf.c > index 5cd9137..75295c8 100644 > --- a/lib/librte_mbuf/rte_mbuf.c > +++ b/lib/librte_mbuf/rte_mbuf.c > @@ -238,6 +238,7 @@ const char *rte_get_tx_ol_flag_name(uint64_t mask) > case PKT_TX_UDP_CKSUM: return "PKT_TX_UDP_CKSUM"; > case PKT_TX_IEEE1588_TMST: return "PKT_TX_IEEE1588_TMST"; > case PKT_TX_VXLAN_CKSUM: return "PKT_TX_VXLAN_CKSUM"; > + case PKT_TX_TCP_SEG: return "PKT_TX_TCP_SEG"; > default: return NULL; > } > } > diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h > index 3c8e825..9f44d08 100644 > --- a/lib/librte_mbuf/rte_mbuf.h > +++ b/lib/librte_mbuf/rte_mbuf.h > @@ -127,6 +127,20 @@ extern "C" { > > #define PKT_TX_VXLAN_CKSUM (1ULL << 50) /**< TX checksum of VXLAN computed > by NIC */ > > +/** > + * TCP segmentation offload. To enable this offload feature for a > + * packet to be transmitted on hardware supporting TSO: > + * - set the PKT_TX_TCP_SEG flag in mbuf->ol_flags (this flag implies > + * PKT_TX_TCP_CKSUM) > + * - if it's IPv4, set the PKT_TX_IP_CKSUM flag and write the IP checksum > + * to 0 in the packet > + * - fill the mbuf offload information: l2_len, l3_len, l4_len, tso_segsz > + * - calculate the pseudo header checksum without taking ip_len in accound, > + * and set it in the TCP header. Refer to rte_ipv4_phdr_cksum() and > + * rte_ipv6_phdr_cksum() that can be used as helpers. > + */ > +#define PKT_TX_TCP_SEG (1ULL << 49) > + > /* Use final bit of flags to indicate a control mbuf */ > #define CTRL_MBUF_FLAG (1ULL << 63) /**< Mbuf contains control data */ > > @@ -228,22 +242,18 @@ struct rte_mbuf { > > /* fields to support TX offloads */ > union { > - uint16_t l2_l3_len; /**< combined l2/l3 lengths as single var */ > + uint64_t tx_offload; /**< combined for easy fetch */ > struct { > - uint16_t l3_len:9; /**< L3 (IP) Header Length. */ > - uint16_t l2_len:7; /**< L2 (MAC) Header Length. */ > - }; > - }; > + uint64_t l2_len:7; /**< L2 (MAC) Header Length. */ > + 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 */ > > - /* fields for TX offloading of tunnels */ > - union { > - uint16_t inner_l2_l3_len; > - /**< combined inner l2/l3 lengths as single var */ > - struct { > - uint16_t inner_l3_len:9; > - /**< inner L3 (IP) Header Length. */ > - uint16_t inner_l2_len:7; > - /**< inner L2 (MAC) Header Length. */ > + /* fields for TX offloading of tunnels */ > + uint64_t inner_l3_len:9; /**< inner L3 (IP) Hdr Length. > */ > + uint64_t inner_l2_len:7; /**< inner L2 (MAC) Hdr > Length. */ > + > + /* uint64_t unused:8; */ > }; > }; > } __rte_cache_aligned; > @@ -595,8 +605,7 @@ static inline void rte_pktmbuf_reset(struct rte_mbuf *m) > { > m->next = NULL; > m->pkt_len = 0; > - m->l2_l3_len = 0; > - m->inner_l2_l3_len = 0; > + m->tx_offload = 0; > m->vlan_tci = 0; > m->nb_segs = 1; > m->port = 0xff; > @@ -665,8 +674,7 @@ static inline void rte_pktmbuf_attach(struct rte_mbuf > *mi, struct rte_mbuf *md) > mi->data_len = md->data_len; > mi->port = md->port; > mi->vlan_tci = md->vlan_tci; > - mi->l2_l3_len = md->l2_l3_len; > - mi->inner_l2_l3_len = md->inner_l2_l3_len; > + mi->tx_offload = md->tx_offload; > mi->hash = md->hash; > > mi->next = NULL; > diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h > index 9cfca7f..1fafa73 100644 > --- a/lib/librte_net/rte_ip.h > +++ b/lib/librte_net/rte_ip.h > @@ -80,6 +80,7 @@ > > #include <rte_memcpy.h> > #include <rte_byteorder.h> > +#include <rte_mbuf.h> > > #ifdef __cplusplus > extern "C" { > @@ -308,13 +309,21 @@ rte_ipv4_cksum(const struct ipv4_hdr *ipv4_hdr) > * > * The checksum field must be set to 0 by the caller. > * > + * Depending on the ol_flags, the pseudo-header checksum expected by the > + * drivers is not the same. For instance, when TSO is enabled, the IP > + * payload length must not be included in the packet. > + * > + * When ol_flags is 0, it computes the standard pseudo-header checksum. > + * > * @param ipv4_hdr > * The pointer to the contiguous IPv4 header. > + * @param ol_flags > + * The ol_flags of the associated mbuf. > * @return > * The non-complemented checksum to set in the L4 header. > */ > static inline uint16_t > -rte_ipv4_phdr_cksum(const struct ipv4_hdr *ipv4_hdr) > +rte_ipv4_phdr_cksum(const struct ipv4_hdr *ipv4_hdr, uint64_t ol_flags) > { > struct ipv4_psd_header { > uint32_t src_addr; /* IP address of source host. */ > @@ -328,9 +337,13 @@ rte_ipv4_phdr_cksum(const struct ipv4_hdr *ipv4_hdr) > psd_hdr.dst_addr = ipv4_hdr->dst_addr; > psd_hdr.zero = 0; > psd_hdr.proto = ipv4_hdr->next_proto_id; > - psd_hdr.len = rte_cpu_to_be_16( > - (uint16_t)(rte_be_to_cpu_16(ipv4_hdr->total_length) > - - sizeof(struct ipv4_hdr))); > + if (ol_flags & PKT_TX_TCP_SEG) { > + psd_hdr.len = 0; > + } else { > + psd_hdr.len = rte_cpu_to_be_16( > + (uint16_t)(rte_be_to_cpu_16(ipv4_hdr->total_length) > + - sizeof(struct ipv4_hdr))); > + } > return rte_raw_cksum((const char *)&psd_hdr, sizeof(psd_hdr)); > } > > @@ -357,7 +370,7 @@ rte_ipv4_udptcp_cksum(const struct ipv4_hdr *ipv4_hdr, > const void *l4_hdr) > sizeof(struct ipv4_hdr); > > cksum = rte_raw_cksum(l4_hdr, l4_len); > - cksum += rte_ipv4_phdr_cksum(ipv4_hdr); > + cksum += rte_ipv4_phdr_cksum(ipv4_hdr, 0); > > cksum = ((cksum & 0xffff0000) >> 16) + (cksum & 0xffff); > cksum = (~cksum) & 0xffff; > @@ -382,13 +395,21 @@ struct ipv6_hdr { > /** > * Process the pseudo-header checksum of an IPv6 header. > * > + * Depending on the ol_flags, the pseudo-header checksum expected by the > + * drivers is not the same. For instance, when TSO is enabled, the IPv6 > + * payload length must not be included in the packet. > + * > + * When ol_flags is 0, it computes the standard pseudo-header checksum. > + * > * @param ipv6_hdr > * The pointer to the contiguous IPv6 header. > + * @param ol_flags > + * The ol_flags of the associated mbuf. > * @return > * The non-complemented checksum to set in the L4 header. > */ > static inline uint16_t > -rte_ipv6_phdr_cksum(const struct ipv6_hdr *ipv6_hdr) > +rte_ipv6_phdr_cksum(const struct ipv6_hdr *ipv6_hdr, uint64_t ol_flags) > { > struct ipv6_psd_header { > uint8_t src_addr[16]; /* IP address of source host. */ > @@ -400,7 +421,11 @@ rte_ipv6_phdr_cksum(const struct ipv6_hdr *ipv6_hdr) > rte_memcpy(&psd_hdr.src_addr, ipv6_hdr->src_addr, > sizeof(ipv6_hdr->src_addr) + sizeof(ipv6_hdr->dst_addr)); > psd_hdr.proto = (ipv6_hdr->proto << 24); > - psd_hdr.len = ipv6_hdr->payload_len; > + if (ol_flags & PKT_TX_TCP_SEG) { > + psd_hdr.len = 0; > + } else { > + psd_hdr.len = ipv6_hdr->payload_len; > + } > > return rte_raw_cksum((const char *)&psd_hdr, sizeof(psd_hdr)); > } > diff --git a/lib/librte_pmd_e1000/igb_rxtx.c b/lib/librte_pmd_e1000/igb_rxtx.c > index 433c616..848d5d1 100644 > --- a/lib/librte_pmd_e1000/igb_rxtx.c > +++ b/lib/librte_pmd_e1000/igb_rxtx.c > @@ -367,6 +367,13 @@ eth_igb_xmit_pkts(void *tx_queue, struct rte_mbuf > **tx_pkts, > struct rte_mbuf *tx_pkt; > struct rte_mbuf *m_seg; > union igb_vlan_macip vlan_macip_lens; > + union { > + uint16_t u16; > + struct { > + uint16_t l3_len:9; > + uint16_t l2_len:7; > + }; > + } l2_l3_len; > uint64_t buf_dma_addr; > uint32_t olinfo_status; > uint32_t cmd_type_len; > @@ -404,8 +411,10 @@ eth_igb_xmit_pkts(void *tx_queue, struct rte_mbuf > **tx_pkts, > tx_last = (uint16_t) (tx_id + tx_pkt->nb_segs - 1); > > ol_flags = tx_pkt->ol_flags; > + l2_l3_len.l2_len = tx_pkt->l2_len; > + l2_l3_len.l3_len = tx_pkt->l3_len; > vlan_macip_lens.f.vlan_tci = tx_pkt->vlan_tci; > - vlan_macip_lens.f.l2_l3_len = tx_pkt->l2_l3_len; > + vlan_macip_lens.f.l2_l3_len = l2_l3_len.u16; > tx_ol_req = ol_flags & IGB_TX_OFFLOAD_MASK; > > /* If a Context Descriptor need be built . */ > diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c > b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c > index ca35db2..2df3385 100644 > --- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c > +++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c > @@ -546,6 +546,13 @@ ixgbe_xmit_pkts(void *tx_queue, struct rte_mbuf > **tx_pkts, > struct rte_mbuf *tx_pkt; > struct rte_mbuf *m_seg; > union ixgbe_vlan_macip vlan_macip_lens; > + union { > + uint16_t u16; > + struct { > + uint16_t l3_len:9; > + uint16_t l2_len:7; > + }; > + } l2_l3_len; > uint64_t buf_dma_addr; > uint32_t olinfo_status; > uint32_t cmd_type_len; > @@ -588,8 +595,10 @@ ixgbe_xmit_pkts(void *tx_queue, struct rte_mbuf > **tx_pkts, > /* If hardware offload required */ > tx_ol_req = ol_flags & IXGBE_TX_OFFLOAD_MASK; > if (tx_ol_req) { > + l2_l3_len.l2_len = tx_pkt->l2_len; > + l2_l3_len.l3_len = tx_pkt->l3_len; > vlan_macip_lens.f.vlan_tci = tx_pkt->vlan_tci; > - vlan_macip_lens.f.l2_l3_len = tx_pkt->l2_l3_len; > + vlan_macip_lens.f.l2_l3_len = l2_l3_len.u16; > > /* If new context need be built or reuse the exist ctx. > */ > ctx = what_advctx_update(txq, tx_ol_req, > -- > 2.1.0