Re: [dpdk-dev] [PATCH v2 1/2] app/testpmd: add link speed check before port start

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

On 4/30/21 6:19 AM, Li, Xiaoyun wrote:
> 
>> -----Original Message-----
>> From: Min Hu (Connor) <humin29@huawei.com>
>> Sent: Wednesday, April 28, 2021 16:37
>> To: dev@dpdk.org
>> Cc: Yigit, Ferruh <ferruh.yigit@intel.com>; Li, Xiaoyun <xiaoyun.li@intel.com>
>> Subject: [PATCH v2 1/2] app/testpmd: add link speed check before port start
>>
>> From: Huisong Li <lihuisong@huawei.com>
>>
>> Currently, to check whether the configured link_speeds is valid, we have to run
>> "port start". In addition, if the configuration fails, "port->dev_conf.link_speeds"
>> maintained in testpmd cannot be restored.
>>
>> This patch adds the link_speeds check before port start by calling dev_configure,
>> and resolves these problems.
> 
> Not sure about this patch. I don't think you can fix the issue you mentioned.
> Probably only hns3 does speed check in dev_configure. I don't see this in other drivers, not in i40e/ice/mlx.

The configuration check may be done by passing the
configuration to HW and HW may reject it.
(Just as a side note that it is not that simple/)

> I guess it's because if it's not supported speed, it will just be UNKNOWN and user can config again?
> 
> BTW, even if this behavior is accepted by others, still some comments below.
> 

[snip]