Re: [PATCH net-next 0/8] nfp: offload LAG for tc flower egress

[Jiri Pirko <jiri@resnulli.us>]

Wed, May 30, 2018 at 11:26:23AM CEST, john.hurley@netronome.com wrote:
>On Tue, May 29, 2018 at 11:09 PM, Jiri Pirko <jiri@resnulli.us> wrote:
>> Tue, May 29, 2018 at 04:08:48PM CEST, john.hurley@netronome.com wrote:
>>>On Sat, May 26, 2018 at 3:47 AM, Jakub Kicinski
>>><jakub.kicinski@netronome.com> wrote:
>>>> On Fri, 25 May 2018 08:48:09 +0200, Jiri Pirko wrote:
>>>>> Thu, May 24, 2018 at 04:22:47AM CEST, jakub.kicinski@netronome.com wrote:
>>>>> >Hi!
>>>>> >
>>>>> >This series from John adds bond offload to the nfp driver.  Patch 5
>>>>> >exposes the hash type for NETDEV_LAG_TX_TYPE_HASH to make sure nfp
>>>>> >hashing matches that of the software LAG.  This may be unnecessarily
>>>>> >conservative, let's see what LAG maintainers think :)
>>>>>
>>>>> So you need to restrict offload to only certain hash algo? In mlxsw, we
>>>>> just ignore the lag setting and do some hw default hashing. Would not be
>>>>> enough? Note that there's a good reason for it, as you see, in team, the
>>>>> hashing is done in a BPF function and could be totally arbitrary.
>>>>> Your patchset effectively disables team offload for nfp.
>>>>
>>>> My understanding is that the project requirements only called for L3/L4
>>>> hash algorithm offload, hence the temptation to err on the side of
>>>> caution and not offload all the bond configurations.  John can provide
>>>> more details.  Not being able to offload team is unfortunate indeed.
>>>
>>>Hi Jiri,
>>>Yes, as Jakub mentions, we restrict ourselves to L3/L4 hash algorithm
>>>as this is currently what is supported in fw.
>>
>> In mlxsw, a default l3/l4 is used always, no matter what the
>> bonding/team sets. It is not correct, but it works with team as well.
>> Perhaps we can have NETDEV_LAG_HASH_UNKNOWN to indicate to the driver to
>> do some default? That would make the "team" offload functional.
>>
>
>yes, I would agree with that.
>Thanks

Okay, would you please adjust your driver?

I will teka care of mlxsw bits.

Thanks!

>
>>>Hopefully this will change as fw features are expanded.
>>>I understand the issue this presents with offloading team.
>>>Perhaps resorting to a default hw hash for team is acceptable.
>>>John