Re: [dpdk-dev] [PATCH v8 0/3]: Add LRO support to ixgbe PMD

[Vlad Zolotarov <vladz@cloudius-systems.com>]

On 03/18/15 19:52, Vlad Zolotarov wrote:
> This series adds the missing flow for enabling the LRO in the ethdev and
> adds a support for this feature in the ixgbe PMD. There is a big hope that this
> initiative is going to be picked up by some Intel developer that would add the LRO support
> to other Intel PMDs.
>
> The series starts with some cleanup work in the code the final patch (the actual adding of
> the LRO support) is going to touch/use/change. There are still quite a few issues in the ixgbe
> PMD code left but they have to be a matter of a different series and I've left a few "TODO"
> remarks in the code.
>
> The LRO ("RSC" in Intel's context) PMD completion handling code follows the same design as the
> corresponding Linux and FreeBSD implementation: pass the aggregation's cluster HEAD buffer to
> the NEXTP entry of the software ring till EOP is met.
>
> HW configuration follows the corresponding specs: this feature is supported only by x540 and
> 82599 PF devices.
>
> The feature has been tested with seastar TCP stack with the following configuration on Tx side:
>     - MTU: 400B
>     - 100 concurrent TCP connections.
>
> The results were:
>     - Without LRO: total throughput: 0.12Gbps, coefficient of variance: 1.41%
>     - With LRO:    total throughput: 8.21Gbps, coefficient of variance: 0.59%
>
> This is an almost factor 80 improvement.

ping

>
> New in v8:
>     - Fixed the structs naming: igb_xxx -> ixgbe_xxx (some leftovers in PATCH2).
>     - Took the RSC configuration code from ixgbe_dev_rx_init() into a separate
>       function - ixgbe_set_rsc().
>     - Added some missing macros for HW configuration.
>     - Styling adjustments:
>        - Functions names.
>        - Functions descriptions.
>     - Reworked the ixgbe_free_rsc_cluster() code to make it more readable.
>     - Kill the HEADER_SPLIT flow in ixgbe_set_rsc() since it's not supported by
>       ixgbe PMD.
>
> New in v7:
>     - Free not-yet-completed RSC aggregations in rte_eth_dev_stop() flow.
>     - Fixed rx_bulk_alloc_allowed and rx_vec_allowed initialization:
>        - Don't set them to FALSE in rte_eth_dev_stop() flow - the following
>          rte_eth_dev_start() will need them.
>        - Reset them to TRUE in rte_eth_dev_configure() and not in a probe() flow.
>          This will ensure the proper behaviour if port is re-configured.
>     - Reset the sw_ring[].mbuf entry in a bulk allocation case.
>       This is needed for ixgbe_rx_queue_release_mbufs().
>     - _recv_pkts_lro(): added the missing memory barrier before RDT update in a
>       non-bulk allocation case.
>     - Don't allow RSC when device is configured in an SR-IOV mode.
>
> New in v6:
>     - Fix of the typo in the "bug fixes" series that broke the compilation caused a
>       minor change in this follow-up series.
>
> New in v5:
>     - Split the series into "bug fixes" and "all the rest" so that the former could be
>       integrated into a 2.0 release.
>     - Put the RTE_ETHDEV_HAS_LRO_SUPPORT definition at the beginning of rte_ethdev.h.
>     - Removed the "TODO: Remove me" comment near RTE_ETHDEV_HAS_LRO_SUPPORT.
>
> New in v4:
>     - Remove CONFIG_RTE_ETHDEV_LRO_SUPPORT from config/common_linuxapp.
>     - Define RTE_ETHDEV_HAS_LRO_SUPPORT in rte_ethdev.h.
>     - As a result of "ixgbe: check rxd number to avoid mbuf leak" (352078e8e) Vector Rx
>       had to get the same treatment as Rx Bulk Alloc (see PATCH4 for more details).
>
> New in v3:
>     - ixgbe_rx_alloc_bufs(): Always reset refcnt of the buffers to 1. Otherwise rte_pktmbuf_free()
>       won't free them.
>
> New in v2:
>     - Removed rte_eth_dev_data.lro_bulk_alloc and added ixgbe_hw.rx_bulk_alloc_allowed
>       instead.
>     - Unified the rx_pkt_bulk callback setting (a separate new patch).
>     - Fixed a few styling and spelling issues.
>
>
> Vlad Zolotarov (3):
>    ixgbe: Cleanups
>    ixgbe: Code refactoring
>    ixgbe: Add LRO support
>
>   lib/librte_ether/rte_ethdev.h           |   9 +-
>   lib/librte_net/rte_ip.h                 |   3 +
>   lib/librte_pmd_ixgbe/ixgbe/ixgbe_type.h |   6 +
>   lib/librte_pmd_ixgbe/ixgbe_ethdev.c     |  11 +
>   lib/librte_pmd_ixgbe/ixgbe_ethdev.h     |   5 +
>   lib/librte_pmd_ixgbe/ixgbe_rxtx.c       | 766 +++++++++++++++++++++++++++++---
>   lib/librte_pmd_ixgbe/ixgbe_rxtx.h       |   6 +
>   7 files changed, 737 insertions(+), 69 deletions(-)
>