Re: [dpdk-dev] [PATCH v5] app/testpmd: fix the default RSS key configuration

[oulijun <oulijun@huawei.com>]

在 2020/10/16 14:46, Ophir Munk 写道:
> 
> 
>> -----Original Message-----
>> From: Ferruh Yigit <ferruh.yigit@intel.com>
> <..>
>>>>
>>>
>>> Ferruh, your suggestion ([1] + update) looks correct. I also verified it on
>> mlx5 PMD.
>>> Advantage: it's a generic fix for all dpdk applications using rte_flows (not
>> just testpmd).
>>> It reduces code.
>>> With this fix the responsibility of handling key==NULL and/or len==0 is
>> moved to the PMDs (which is good).
>>>
>>> With regard to Lijun patch - I liked the approach of overriding the default
>> testpmd key with the default PMD key.
>>> But it only addresses testpmd. More code was added.
>>> It seems OK to call rte_eth_dev_rss_hash_conf_get() as part of parsing
>> RSS, but it would feel more confident if we could confirm it for all the PMDs
>> (by testing) or at least review the PMDs rss_hash_conf_get()
>> implementations.
>>>
>>
>> Lijun's idea can work. There was a problem in implementation related to the
>> key size assumption, which can be fixed.
>>
>> Even it is fixed, when user gives a rss rule without a key, we are getting key
>> from device and feeding same key back to device, this is unnecessary I think.
> 
> I agree.
> 
>> When user didn't provide a key, rss rule shouldn't touch the key at all.
> 
> Agreed as well.
> 
>> Complication was when user provides key_len without a key, I think both
>> ignoring or returning error in this case is OK.
> 
> I think that in general flow rules should arrive "as is" to the PMD which has its
> validation and translation APIs to handle all cases.
> 
Do you agree with [1] + Ferruh update solution？