Re: [dpdk-dev] [PATCH] net/i40evf: add multicast MAC address filtering

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 3/28/2018 3:23 PM, Zhang, Qi Z wrote:
> 
> 
>> -----Original Message-----
>> From: Yigit, Ferruh
>> Sent: Wednesday, March 28, 2018 9:53 PM
>> To: Zhang, Qi Z <qi.z.zhang@intel.com>; Olivier Matz
>> <olivier.matz@6wind.com>; dev@dpdk.org; Xing, Beilei
>> <beilei.xing@intel.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>; Thomas
>> Monjalon <thomas@monjalon.net>
>> Subject: Re: [dpdk-dev] [PATCH] net/i40evf: add multicast MAC address
>> filtering
>>
>> On 3/28/2018 11:15 AM, Zhang, Qi Z wrote:
>>> Hi Ferruh:
>>>
>>>> -----Original Message-----
>>>> From: Yigit, Ferruh
>>>> Sent: Wednesday, March 28, 2018 6:01 PM
>>>> To: Zhang, Qi Z <qi.z.zhang@intel.com>; Olivier Matz
>>>> <olivier.matz@6wind.com>; dev@dpdk.org; Xing, Beilei
>>>> <beilei.xing@intel.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>
>>>> Subject: Re: [dpdk-dev] [PATCH] net/i40evf: add multicast MAC address
>>>> filtering
>>>>
>>>> On 3/27/2018 2:51 PM, Zhang, Qi Z wrote:
>>>>>
>>>>>
>>>>>> -----Original Message-----
>>>>>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Olivier Matz
>>>>>> Sent: Thursday, January 25, 2018 10:36 PM
>>>>>> To: dev@dpdk.org; Xing, Beilei <beilei.xing@intel.com>; Zhang, Qi Z
>>>>>> <qi.z.zhang@intel.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>
>>>>>> Subject: [dpdk-dev] [PATCH] net/i40evf: add multicast MAC address
>>>>>> filtering
>>>>>>
>>>>>> Add support the set_mc_addr_list device operation in the i40evf PMD.
>>>>>>
>>>>>> The configured addresses are stored in the device private area, so
>>>>>> they can be flushed before adding new ones.
>>>>>>
>>>>>> Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
>>>>>
>>>>> Acked-by: Qi Zhang <qi.z.zhang@intel.com>
>>>>>
>>>>> Thanks for enable this!
>>>>
>>>> Hi Qi,
>>>>
>>>> This feature was already documented as supported in i40e_vf.ini which
>>>> seems wrong but now it is supported.
>>>>
>>>> i40e also documents this feature as supported, can you please check
>>>> if the feature is supported there and update i40e.ini if required?
>>>
>>> Do you mean
>>>
>>> " Multicast MAC filter = Y" ?
>>>
>>> My understanding is, though i40e PF/VF doesn't support set_mc_addr_list,
>> but we still can use mac_addr_add to add a multi cast address, so we still
>> have that flag on in i40e.ini.
>>
>> Right, current "mac_addr_add" dev_ops lets setting multicast addresses. In
>> this logic if HW supports setting multicast address PMD may claim this
>> support.
>>
>> Or this may explicitly mean implementing set_mc_addr_list dev_ops in
>> driver.
>>
>>
>> These feature list is to help user / application developer about what to expect
>> and what to not from drivers.
>>
>> A user may expect set_mc_addr_list dev_ops is implemented when this
>> feature documented and it may be confusing when it fails.
>>
>> Overall which information, hw supports setting mc mad address or
>> set_mc_addr_list implemented, adds more value from user point of view?
>> What do you think?
> 
> I'm not sure if it is feasible to bind "Multicast MAC filter = Y" to set_mc_addr_list's implementation only in document.
> For me, I think it's reasonable to support two ways to enable mc filters
> set_mc_addr_list support batch, but it also overwrite, in the case user don't want to overwrite, mac_addr_add could be taken.
> so for i40e, it just not support batch overwrite and if just set "Multicast MAC filter = N" seems a little bit unfair to i40e, 
> properly we should update the document?

As long as agreed on it, no problem on updating the document [1].

[1]
https://dpdk.org/doc/guides/nics/features.html

> 
>>
>>>
>>> Regards
>>> Qi
>>>
>>>>
>>>> Thanks,
>>>> ferruh
>