| Message ID | 20141021112946.30069.67329.stgit@gklab-18-011.igk.intel.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
Hello Miroslaw, On 10/21/2014 01:29 PM, miroslaw.walukiewicz@intel.com wrote: > From: Miroslaw Walukiewicz <miroslaw.walukiewicz@intel.com> > > The NICs supported by DPDK have a possibility to accelerate TCP > traffic by sergnention offload. The application preprares a packet > with valid TCP header with size up to 64K and NIC makes packet > segmenation generating valid checksums and TCP segments. > > The patch defines a generic support for TSO offload. > - Add new PKT_TX_TCP_SEG flag. > Only packets with this flag set in ol_flags will be handled as > TSO packets. > > - Add new fields in indicating TCP TSO segment size and TCP header len. > The TSO requires from application setting following fields in mbuf. > 1. L2 header len including MAC/VLANs/SNAP if present > 2. L3 header len including IP options > 3. L4 header len (new field) including TCP options > 4. tso_segsz (new field) the size of TCP segment > > The apllication has obligation to compute the pseudo header checksum > instead of full TCP checksum and put it in the TCP header csum field. > > Handling complexity of creation combined l2_l3_len field > a new macro RTE_MBUF_TO_L2_L3_LEN() is defined to retrieve this > part of rte_mbuf. > The patch you submitted does not include any changes in a driver (let's say ixgbe as it is the reference) taking advantage it. So it's difficult to validate that your modifications are sufficient to implement TSO. In addition of a driver, I think that testpmd should be modified to validate your changes and give an example to people wanting to use this feature. Based on your patch, I'll try to submit a series in the coming days (maybe today if the winds are favourable) that includes the remaining patches from the original TSO series [1] that were not applied by Bruce's mbuf rework. Regards, Olivier [1] http://dpdk.org/ml/archives/dev/2014-May/002537.html
Hello Olivier, > -----Original Message----- > From: Olivier MATZ [mailto:olivier.matz@6wind.com] > Sent: Friday, October 31, 2014 4:50 PM > To: Walukiewicz, Miroslaw; dev@dpdk.org > Subject: Re: [dpdk-dev] [PATCH v2] pmd: Add generic support for TCP TSO > (Transmit Segmentation Offload) > > Hello Miroslaw, > > On 10/21/2014 01:29 PM, miroslaw.walukiewicz@intel.com wrote: > > From: Miroslaw Walukiewicz <miroslaw.walukiewicz@intel.com> > > > > The NICs supported by DPDK have a possibility to accelerate TCP > > traffic by sergnention offload. The application preprares a packet > > with valid TCP header with size up to 64K and NIC makes packet > > segmenation generating valid checksums and TCP segments. > > > > The patch defines a generic support for TSO offload. > > - Add new PKT_TX_TCP_SEG flag. > > Only packets with this flag set in ol_flags will be handled as > > TSO packets. > > > > - Add new fields in indicating TCP TSO segment size and TCP header len. > > The TSO requires from application setting following fields in mbuf. > > 1. L2 header len including MAC/VLANs/SNAP if present > > 2. L3 header len including IP options > > 3. L4 header len (new field) including TCP options > > 4. tso_segsz (new field) the size of TCP segment > > > > The apllication has obligation to compute the pseudo header checksum > > instead of full TCP checksum and put it in the TCP header csum field. > > > > Handling complexity of creation combined l2_l3_len field > > a new macro RTE_MBUF_TO_L2_L3_LEN() is defined to retrieve this > > part of rte_mbuf. > > > > The patch you submitted does not include any changes in a driver > (let's say ixgbe as it is the reference) taking advantage it. > So it's difficult to validate that your modifications are sufficient > to implement TSO. I wanted to agree on the generic TSO API first and next to make driver modifications in next patches. > > In addition of a driver, I think that testpmd should be modified > to validate your changes and give an example to people wanting to use > this feature. > > Based on your patch, I'll try to submit a series in the coming days > (maybe today if the winds are favourable) that includes the remaining > patches from the original TSO series [1] that were not applied by > Bruce's mbuf rework. > Thank you Olivier, I will follow your patches with my i40e TSO changes when generic API will be accepted by community. > Regards, > Olivier > > [1] http://dpdk.org/ml/archives/dev/2014-May/002537.html
diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c index f76406f..d8fd025 100644 --- a/app/test-pmd/testpmd.c +++ b/app/test-pmd/testpmd.c @@ -408,7 +408,8 @@ 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->l2_len = 0; + mb->l3_len = 0; mb->vlan_tci = 0; mb->hash.rss = 0; } diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h index ddadc21..2e2e315 100644 --- a/lib/librte_mbuf/rte_mbuf.h +++ b/lib/librte_mbuf/rte_mbuf.h @@ -114,6 +114,9 @@ extern "C" { /* Bit 51 - IEEE1588*/ #define PKT_TX_IEEE1588_TMST (1ULL << 51) /**< TX IEEE1588 packet to timestamp. */ +/* Bit 49 - TCP transmit segmenation offload */ +#define PKT_TX_TCP_SEG (1ULL << 49) /**< TX TSO offload */ + /* Use final bit of flags to indicate a control mbuf */ #define CTRL_MBUF_FLAG (1ULL << 63) /**< Mbuf contains control data */ @@ -189,16 +192,28 @@ struct rte_mbuf { struct rte_mbuf *next; /**< Next segment of scattered packet. */ /* fields to support TX offloads */ - union { - uint16_t l2_l3_len; /**< combined l2/l3 lengths as single var */ + /* two bytes - l2 len (including MAC/VLANs/SNAP if present) + * two bytes - l3 len (including IP options) + * two bytes - l4 len TCP/UDP header len - including TCP options + * two bytes - TCP tso segment size + */ + union{ + uint64_t l2_l3_l4_tso_seg; /**< combined for easy fetch */ struct { - uint16_t l3_len:9; /**< L3 (IP) Header Length. */ - uint16_t l2_len:7; /**< L2 (MAC) Header Length. */ + uint16_t l3_len; /**< L3 (IP) Header */ + uint16_t l2_len; /**< L2 (MAC) Header */ + uint16_t l4_len; /**< TCP/UDP header len */ + uint16_t tso_segsz; /**< TCP TSO segment size */ }; }; } __rte_cache_aligned; /** + * Given the rte_mbuf returns the l2_l3_len combined + */ +#define RTE_MBUF_TO_L2_L3_LEN(mb) (uint32_t)(((mb)->l2_len << 16) | (mb)->l3_len) + +/** * Given the buf_addr returns the pointer to corresponding mbuf. */ #define RTE_MBUF_FROM_BADDR(ba) (((struct rte_mbuf *)(ba)) - 1) @@ -545,7 +560,7 @@ static inline void rte_pktmbuf_reset(struct rte_mbuf *m) { m->next = NULL; m->pkt_len = 0; - m->l2_l3_len = 0; + m->l2_l3_l4_tso_seg = 0; m->vlan_tci = 0; m->nb_segs = 1; m->port = 0xff; @@ -613,7 +628,7 @@ 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->l2_l3_l4_tso_seg = md->l2_l3_l4_tso_seg; mi->hash = md->hash; mi->next = NULL; diff --git a/lib/librte_pmd_e1000/igb_rxtx.c b/lib/librte_pmd_e1000/igb_rxtx.c index f09c525..0f3248e 100644 --- a/lib/librte_pmd_e1000/igb_rxtx.c +++ b/lib/librte_pmd_e1000/igb_rxtx.c @@ -399,7 +399,7 @@ eth_igb_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, ol_flags = tx_pkt->ol_flags; 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 = RTE_MBUF_TO_L2_L3_LEN(tx_pkt); tx_ol_req = ol_flags & PKT_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 123b8b3..5e92224 100644 --- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c +++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c @@ -583,7 +583,7 @@ ixgbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, tx_ol_req = ol_flags & PKT_TX_OFFLOAD_MASK; if (tx_ol_req) { 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 = RTE_MBUF_TO_L2_L3_LEN(tx_pkt); /* If new context need be built or reuse the exist ctx. */ ctx = what_advctx_update(txq, tx_ol_req,