Ubuntu Manpage: rte_eth_rxseg

NAME

       rte_eth_rxseg_split

SYNOPSIS

       #include <rte_ethdev.h>

   Data Fields
       struct rte_mempool * mp
       uint16_t length
       uint16_t offset
       uint32_t proto_hdr

Detailed Description

Warning
EXPERIMENTAL: this structure may change without prior notice.

A structure used to configure an Rx packet segment to split.

If RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT flag is set in offloads field, the PMD will split the received packets
into multiple segments according to the specification in the description array:

• The first network buffer will be allocated from the memory pool, specified in the first array element,
the second buffer, from the pool in the second element, and so on.

• The proto_hdrs in the elements define the split position of received packets.

• The offsets from the segment description elements specify the data offset from the buffer beginning
except the first mbuf. The first segment offset is added with RTE_PKTMBUF_HEADROOM.

• The lengths in the elements define the maximal data amount being received to each segment. The
receiving starts with filling up the first mbuf data buffer up to specified length. If the there are
data remaining (packet is longer than buffer in the first mbuf) the following data will be pushed to
the next segment up to its own length, and so on.

• If the length in the segment description element is zero the actual buffer size will be deduced from
the appropriate memory pool properties.

• If there is not enough elements to describe the buffer for entire packet of maximal length the
following parameters will be used for the all remaining segments:

• pool from the last valid element

• the buffer size from this pool

• zero offset

• Length based buffer split:

• mp, length, offset should be configured.

• The proto_hdr field must be 0.

• Protocol header based buffer split:

• mp, offset, proto_hdr should be configured.

• The length field must be 0.

• The proto_hdr field in the last segment should be 0.

• When protocol header split is enabled, NIC may receive packets which do not match all the protocol
headers within the Rx segments. At this point, NIC will have two possible split behaviors according to
matching results, one is exact match, another is longest match. The split result of NIC must belong to
one of them. The exact match means NIC only do split when the packets exactly match all the protocol
headers in the segments. Otherwise, the whole packet will be put into the last valid mempool. The
longest match means NIC will do split until packets mismatch the protocol header in the segments. The
rest will be put into the last valid pool.

Definition at line 1092 of file rte_ethdev.h.

Field Documentation

   struct rte_mempool* mp
       Memory pool to allocate segment from.

       Definition at line 1093 of file rte_ethdev.h.

   uint16_t length
       Segment data length, configures split point.

       Definition at line 1094 of file rte_ethdev.h.

   uint16_t offset
       Data offset from beginning of mbuf data buffer.

       Definition at line 1095 of file rte_ethdev.h.

   uint32_t proto_hdr
       proto_hdr defines a bit mask of the protocol sequence as RTE_PTYPE_*. The last  RTE_PTYPE*  in  the  mask
       indicates the split position.

       If  one  protocol  header  is  defined to split packets into two segments, for non-tunneling packets, the
       complete protocol sequence should be defined. For tunneling packets, for simplicity, only the tunnel  and
       inner  part  of  complete protocol sequence is required. If several protocol headers are defined to split
       packets into multi-segments, the repeated parts of adjacent segments should be omitted.

       Definition at line 1107 of file rte_ethdev.h.

Author

       Generated automatically by Doxygen for DPDK from the source code.

DPDK                                             Version 24.11.2                          rte_eth_rxseg_split(3)