Re: [PATCH net-next v6 2/4] ethtool: provide customized dim profile management

[Brett Creeley <bcreeley@amd.com>]

On 4/11/2024 7:07 PM, Heng Qi wrote:
> Caution: This message originated from an External Source. Use proper 
> caution when opening attachments, clicking links, or responding.
> 
> 
> 在 2024/4/11 下午11:19, Brett Creeley 写道:
>>
>>
>> On 4/11/2024 7:12 AM, Heng Qi wrote:
>>> Caution: This message originated from an External Source. Use proper
>>> caution when opening attachments, clicking links, or responding.
>>>
>>>
>>> The NetDIM library, currently leveraged by an array of NICs, delivers
>>> excellent acceleration benefits. Nevertheless, NICs vary significantly
>>> in their dim profile list prerequisites.
>>>
>>> Specifically, virtio-net backends may present diverse sw or hw device
>>> implementation, making a one-size-fits-all parameter list impractical.
>>> On Alibaba Cloud, the virtio DPU's performance under the default DIM
>>> profile falls short of expectations, partly due to a mismatch in
>>> parameter configuration.
>>>
>>> I also noticed that ice/idpf/ena and other NICs have customized
>>> profilelist or placed some restrictions on dim capabilities.
>>>
>>> Motivated by this, I tried adding new params for "ethtool -C" that
>>> provides
>>> a per-device control to modify and access a device's interrupt
>>> parameters.
>>>
>>> Usage
>>> ========
>>> 1. Query the currently customized list of the device
>>>
>>> $ ethtool -c ethx
>>> ...
>>> rx-eqe-profile:
>>> {.usec =   1, .pkts = 256, .comps =   0,},
>>> {.usec =   8, .pkts = 256, .comps =   0,},
>>> {.usec =  64, .pkts = 256, .comps =   0,},
>>> {.usec = 128, .pkts = 256, .comps =   0,},
>>> {.usec = 256, .pkts = 256, .comps =   0,}
>>> rx-cqe-profile:   n/a
>>> tx-eqe-profile:   n/a
>>> tx-cqe-profile:   n/a
>>>
>>> 2. Tune
>>> $ ethtool -C ethx rx-eqe-profile 1,1,0_2,2,0_3,3,0_4,4,0_5,5,0
>>> $ ethtool -c ethx
>>> ...
>>> rx-eqe-profile:
>>> {.usec =   1, .pkts =   1, .comps =   0,},
>>> {.usec =   2, .pkts =   2, .comps =   0,},
>>> {.usec =   3, .pkts =   3, .comps =   0,},
>>> {.usec =   4, .pkts =   4, .comps =   0,},
>>> {.usec =   5, .pkts =   5, .comps =   0,}
>>> rx-cqe-profile:   n/a
>>> tx-eqe-profile:   n/a
>>> tx-cqe-profile:   n/a
>>>
>>> 3. Hint
>>> If the device does not support some type of customized dim
>>> profiles, the corresponding "n/a" will display.
>>
>> What if the user specifies a *-eqe-profile and *-cqe-profile for rx
>> and/or tx? Is that supported? If so, which one is the active profile?
> 
> 
> I think you mean GET? GET currently does not support any parameters, the
> working profile will be displayed.

Yeah, I meant the GET operation. As long as the currently in-use/working 
profile is displayed that makes sense.

> 
>>
>> Maybe I missed this, but it doesn't seem like the output from "ethtool
>> -c ethX" shows the active profile it just dumps the profile
>> configurations.
> 
> Now it is required that dev->priv_flags is set to one of
> IFF_PROFILE_{USEC, PKTS, COMPS} (which means that the
> driver supports configurable profiles) before the profile can be queried
> or do you want to query without this restriction?

No, just as I mentioned above it seems okay.

> 
> Thanks!
> 
>>
>> Thanks,
>>
>> Brett
>>
>> [snip]
>