Re: [dpdk-dev] [PATCH v7 0/3]: Add LRO support to ixgbe PMD

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

On 03/11/15 16:13, Ananyev, Konstantin wrote:
>
>> -----Original Message-----
>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Vlad Zolotarov
>> Sent: Tuesday, March 10, 2015 7:31 PM
>> To: dev@dpdk.org
>> Subject: [dpdk-dev] [PATCH v7 0/3]: Add LRO support to ixgbe PMD
>>
>> 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.
>>
>> 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.
> That changes probably should be part of another patch you submitted:
> [PATCH v2 3/3] ixgbe: Unify the rx_pkt_bulk callbackinitialization
> ?
> Konstantin

Yeah.... ;)

>
>>     - 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_pmd_ixgbe/ixgbe_ethdev.c |  29 +-
>>   lib/librte_pmd_ixgbe/ixgbe_ethdev.h |   5 +
>>   lib/librte_pmd_ixgbe/ixgbe_rxtx.c   | 738 ++++++++++++++++++++++++++++++++----
>>   lib/librte_pmd_ixgbe/ixgbe_rxtx.h   |   6 +
>>   5 files changed, 710 insertions(+), 77 deletions(-)
>>
>> --
>> 2.1.0