[dpdk-dev] [PATCH v4] RSS key use with testpmd

[oulijun]

在 2020/9/30 21:17, Ferruh Yigit 写道:
> On 9/24/2020 2:45 PM, Lijun Ou wrote:
>> Consider the follow usage with testpmd:
>> 1. first, startup testpmd:
>> testpmd> show port 0 rss-hash key
>> RSS functions:
>>   all ipv4-frag ipv4-other ipv6-frag ipv6-other ip
>> RSS key:
>> 6D5A56DA255B0EC24167253D43A38FB0D0CA2BCBAE7B30B477CB2DA38030F
>> 20C6A42B73BBEAC01FA
>> 2. create a rss rule
>> testpmd> flow create 0 ingress pattern eth / ipv4 / udp / end actions 
>> rss \
>> types ipv4-udp end queues end / end
>>
>> 3. show rss-hash key
>> testpmd> show port 0 rss-hash key
>> RSS functions:
>>   all ipv4-udp udp
>> RSS key:
>> 74657374706D6427732064656661756C74205253532068617368206B65792C206F
>> 76657272696465
>>
>> As a result, the step 3 with RSS key and the step 1 RSS key
>> is not the same. The patch[1] to solve the above problems.
>>
> 
> This is interesting, can you please provide above information in the 
> commit log too?
> 
Yes， I submitted detailed operation information in patch v3 as a commit, 
and Yang suggested that the operation information be included in the 
cover letter.
> Also can you please provide the details on why this happens, callstack 
> can help?
> 
When you start the testpmd, the pmd driver initializes the RSS 
configuration. Generally, the recommended RSS hash key is used as the 
default key in the driver. In addition, the default key is different 
from the default RSS flow in testpmd without specifying RSS hash key.
So， if you do not specify the RSS key when creating an RSS rule, the 
testpmd uses the default key as the default RSS key of the RSS rule.As a 
result, you may mistakenly consider that the RSS key in use is the valid 
default key of the NIC, actually, the key and the valid default key of 
the NIC are two values.
> Thanks,
> ferruh
> 
> 
>> Lijun Ou (1):
>>    app/testpmd: fix the default RSS key configuration
>>
>>   app/test-pmd/cmdline_flow.c | 8 ++++++++
>>   1 file changed, 8 insertions(+)
>>
> 
> .
>