27. Solarflare libefx-based Poll Mode Driver

The SFC EFX PMD (librte_pmd_sfc_efx) provides poll mode driver support for Solarflare SFN7xxx and SFN8xxx family of 10/40 Gbps adapters. SFC EFX PMD has support for the latest Linux and FreeBSD operating systems.

More information can be found at Solarflare Communications website.

27.1. Features

SFC EFX PMD has support for:

  • Multiple transmit and receive queues
  • Link state information including link status change interrupt
  • IPv4/IPv6 TCP/UDP transmit checksum offload
  • Inner IPv4/IPv6 TCP/UDP transmit checksum offload
  • Port hardware statistics
  • Extended statistics (see Solarflare Server Adapter User’s Guide for the statistics description)
  • Basic flow control
  • MTU update
  • Jumbo frames up to 9K
  • Promiscuous mode
  • Allmulticast mode
  • TCP segmentation offload (TSO)
  • Multicast MAC filter
  • IPv4/IPv6 TCP/UDP receive checksum offload
  • Inner IPv4/IPv6 TCP/UDP receive checksum offload
  • Received packet type information
  • Receive side scaling (RSS)
  • RSS hash
  • Scattered Rx DMA for packet that are larger that a single Rx descriptor
  • Deferred receive and transmit queue start
  • Transmit VLAN insertion (if running firmware variant supports it)
  • Flow API

27.2. Non-supported Features

The features not yet supported include:

  • Receive queue interupts
  • Priority-based flow control
  • Loopback
  • Configurable RX CRC stripping (always stripped)
  • Header split on receive
  • VLAN filtering
  • VLAN stripping
  • LRO

27.3. Limitations

Due to requirements on receive buffer alignment and usage of the receive buffer for the auxiliary packet information provided by the NIC up to extra 269 (14 bytes prefix plus up to 255 bytes for end padding) bytes may be required in the receive buffer. It should be taken into account when mbuf pool for receive is created.

27.4. Tunnels support

NVGRE, VXLAN and GENEVE tunnels are supported on SFN8xxx family adapters with full-feature firmware variant running. sfboot should be used to configure NIC to run full-feature firmware variant. See Solarflare Server Adapter User’s Guide for details.

SFN8xxx family adapters provide either inner or outer packet classes. If adapter firmware advertises support for tunnels then the PMD configures the hardware to report inner classes, and outer classes are not reported in received packets. However, for VXLAN and GENEVE tunnels the PMD does report UDP as the outer layer 4 packet type.

SFN8xxx family adapters report GENEVE packets as VXLAN. If UDP ports are configured for only one tunnel type then it is safe to treat VXLAN packet type indication as the corresponding UDP tunnel type.

27.5. Flow API support

Supported attributes:

  • Ingress

Supported pattern items:

  • VOID
  • ETH (exact match of source/destination addresses, individual/group match of destination address, EtherType)
  • VLAN (exact match of VID, double-tagging is supported)
  • IPV4 (exact match of source/destination addresses, IP transport protocol)
  • IPV6 (exact match of source/destination addresses, IP transport protocol)
  • TCP (exact match of source/destination ports)
  • UDP (exact match of source/destination ports)

Supported actions:

  • VOID
  • QUEUE
  • RSS

Validating flow rules depends on the firmware variant.

27.5.1. Ethernet destinaton individual/group match

Ethernet item supports I/G matching, if only the corresponding bit is set in the mask of destination address. If destinaton address in the spec is multicast, it matches all multicast (and broadcast) packets, oherwise it matches unicast packets that are not filtered by other flow rules.

27.6. Supported NICs

  • Solarflare Flareon [Ultra] Server Adapters:

    • Solarflare SFN8522 Dual Port SFP+ Server Adapter
    • Solarflare SFN8522M Dual Port SFP+ Server Adapter
    • Solarflare SFN8042 Dual Port QSFP+ Server Adapter
    • Solarflare SFN8542 Dual Port QSFP+ Server Adapter
    • Solarflare SFN8722 Dual Port SFP+ OCP Server Adapter
    • Solarflare SFN7002F Dual Port SFP+ Server Adapter
    • Solarflare SFN7004F Quad Port SFP+ Server Adapter
    • Solarflare SFN7042Q Dual Port QSFP+ Server Adapter
    • Solarflare SFN7122F Dual Port SFP+ Server Adapter
    • Solarflare SFN7124F Quad Port SFP+ Server Adapter
    • Solarflare SFN7142Q Dual Port QSFP+ Server Adapter
    • Solarflare SFN7322F Precision Time Synchronization Server Adapter

27.7. Prerequisites

  • Requires firmware version:

    • SFN7xxx: 4.7.1.1001 or higher
    • SFN8xxx: 6.0.2.1004 or higher

Visit Solarflare Support Downloads to get Solarflare Utilities (either Linux or FreeBSD) with the latest firmware. Follow instructions from Solarflare Server Adapter User’s Guide to update firmware and configure the adapter.

27.8. Pre-Installation Configuration

27.8.1. Config File Options

The following options can be modified in the .config file. Please note that enabling debugging options may affect system performance.

  • CONFIG_RTE_LIBRTE_SFC_EFX_PMD (default y)

    Enable compilation of Solarflare libefx-based poll-mode driver.

  • CONFIG_RTE_LIBRTE_SFC_EFX_DEBUG (default n)

    Enable compilation of the extra run-time consistency checks.

27.8.2. Per-Device Parameters

The following per-device parameters can be passed via EAL PCI device whitelist option like “-w 02:00.0,arg1=value1,...”.

Case-insensitive 1/y/yes/on or 0/n/no/off may be used to specify boolean parameters value.

  • rx_datapath [auto|efx|ef10] (default auto)

    Choose receive datapath implementation. auto allows the driver itself to make a choice based on firmware features available and required by the datapath implementation. efx chooses libefx-based datapath which supports Rx scatter. ef10 chooses EF10 (SFN7xxx, SFN8xxx) native datapath which is more efficient than libefx-based and provides richer packet type classification, but lacks Rx scatter support.

  • tx_datapath [auto|efx|ef10|ef10_simple] (default auto)

    Choose transmit datapath implementation. auto allows the driver itself to make a choice based on firmware features available and required by the datapath implementation. efx chooses libefx-based datapath which supports VLAN insertion (full-feature firmware variant only), TSO and multi-segment mbufs. Mbuf segments may come from different mempools, and mbuf reference counters are treated responsibly. ef10 chooses EF10 (SFN7xxx, SFN8xxx) native datapath which is more efficient than libefx-based but has no VLAN insertion and TSO support yet. Mbuf segments may come from different mempools, and mbuf reference counters are treated responsibly. ef10_simple chooses EF10 (SFN7xxx, SFN8xxx) native datapath which is even more faster then ef10 but does not support multi-segment mbufs, disallows multiple mempools and neglects mbuf reference counters.

  • perf_profile [auto|throughput|low-latency] (default throughput)

    Choose hardware tunning to be optimized for either throughput or low-latency. auto allows NIC firmware to make a choice based on installed licences and firmware variant configured using sfboot.

  • debug_init [bool] (default n)

    Enable extra logging during device initialization and startup.

  • mcdi_logging [bool] (default n)

    Enable extra logging of the communication with the NIC’s management CPU. The logging is done using RTE_LOG() with INFO level and PMD type. The format is consumed by the Solarflare netlogdecode cross-platform tool.

  • stats_update_period_ms [long] (default 1000)

    Adjust period in milliseconds to update port hardware statistics. The accepted range is 0 to 65535. The value of 0 may be used to disable periodic statistics update. One should note that it’s only possible to set an arbitrary value on SFN8xxx provided that firmware version is 6.2.1.1033 or higher, otherwise any positive value will select a fixed update period of 1000 milliseconds