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

[Ferruh Yigit]

On 10/9/2020 1:09 PM, oulijun wrote:
> 
> 
> 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.
 >

OK, understood.
Only, commands helped me to understand the problem, it is easy to grasp the 
issue with samples, so I thought it may help others later in if it is in the 
commit log, since cover letter won't be visible in the git repo.

@Phil, will you be OK to have them in the commit log if the checkpatch warnings 
fixed?

>> 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.

Above description looks good, can you include this to the commit log please?

>> 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(+)
>>>
>>
>> .
>>