[dpdk-dev] ethdev flow director/filtering/steering API

[Andrew Rybchenko]

On 4/12/19 8:57 PM, Ferruh Yigit wrote:
> On 4/11/2019 9:43 AM, Andrew Rybchenko wrote:
>> On 4/11/19 10:49 AM, Thomas Monjalon wrote:
>>> About the features called flow director, filtering or flow steering,
>>> we have some overlap in our API that we should clean.
>>> It is especially important when considering to freeze the API for stability.
>>>
>>> Please read this deprecation notice from December 2016:
>>>
>>> * ethdev: the legacy filter API, including
>>>    ``rte_eth_dev_filter_supported()``, ``rte_eth_dev_filter_ctrl()`` as well
>>>    as filter types MACVLAN, ETHERTYPE, FLEXIBLE, SYN, NTUPLE, TUNNEL, FDIR,
>>>    HASH and L2_TUNNEL, is superseded by the generic flow API (rte_flow) in
>>>    PMDs that implement the latter.
>>>    Target release for removal of the legacy API will be defined once most
>>>    PMDs have switched to rte_flow.
>>>
>>> We must mark the eth_dev_filter API as deprecated and decide about
>>> a date to remove it.
>>>
>>> Which PMD is implementing this API and not rte_flow?
>> In accordance with feature matrix is it i40e_vec, ixgbe_vec and qede, but
>> I think it is just a mistake in documentation.
>>
>> Flow API support tick is missing for many PMDs which actually implement
>> (as far as I can see): bonding, dppa2, e100, mlx4, qede, mvpp2, softnic.
>> I've added maintainers to CC.
> I think having both "Flow control" and "Flow API" is confusing, it looks to me
> "Flow control" is name of the feature, "Flow API" is implementation detail and
> other implementation detail is "Flow director"
>
>  From the consumers point of view, to they need to know if the flow control
> implemented using "Flow API"? This information looks like more driver internal.

Flow control and flow API are absolutely different features.
Flow control is about Ethernet pauses etc.
Flow API is about filtering and actions.
Flow director is mainly filtering approach and I would agree to classify 
it as
implementation detail. I'd consider to move it under flow API umbrella
finally, but I don't know enough details on it.

> Keeping only "Flow control" in feature list, and remove "Flow API" & "Flow
> director", and set "Flow control" as support both with implementations makes
> sense to me. What do you think?
>
>>> If there are still some, deadlines should help them to be converted :)
>>> If some help is needed, please ask.
>>>
>>> Anyway, after more than 2 years of notice, I think it is fair to mark
>>> the legacy API as deprecated in 19.05 release.
>> I agree. I think it is a good idea.
>>
>> Andrew.