Re: [dpdk-dev] [dpdk-stable] [PATCH v2 1/4] power: fix non thread-safe power env modification

[David Hunt <david.hunt@intel.com>]

On 25/10/2020 6:22 PM, Thomas Monjalon wrote:
> 29/03/2019 16:09, Burakov, Anatoly:
>> On 29-Mar-19 2:14 PM, Thomas Monjalon wrote:
>>> 18/03/2019 12:56, Hajkowski:
>>>> From: Marcin Hajkowski <marcinx.hajkowski@intel.com>
>>>> --- a/doc/guides/rel_notes/release_19_05.rst
>>>> +++ b/doc/guides/rel_notes/release_19_05.rst
>>>> @@ -120,6 +120,8 @@ API Changes
>>>> +   * power: ``rte_power_set_env`` and ``rte_power_unset_env`` functions
>>>> +     have been modified to be thread safe.
>>> The deprecation notice was recently sent,
>>> so I guess this patch is for DPDK 19.08.
>> Yes, this is changing API so the target was 19.08. However, first patch
>> is a fix and can be applied to 19.05 as well. The API documentation
>> stated that the function was not thread safe, but the code itself was
>> thread safe (it wasn't because it was buggy, but the intention of being
>> thread safe was there), so this could be considered fixing docs to match
>> the intended behavior of the code.
>>
>>> Review from the maintainer (David) may help.
>>> Thanks
> What is the follow-up here?
> We still have an old deprecation notice:
> 	http://git.dpdk.org/dpdk/commit/?id=3477b7a2cc
>
> I wonder how such things can be forgotten.
> I feel some help is needed in prioritization,
> so let's consider this deprecation as the priority #1
> gating any other change in the power library.


Hi Thomas,

#1 is now done, I've pushed a patch removing the deprication notice to 
the mailing list, as the change it describes had previously been applied.
Patch here: http://patches.dpdk.org/patch/82327/


> Priority #2: cleaning up API which are secretly exported
> for example convenience. It is an old design issue never fixed:
> 	http://inbox.dpdk.org/dev/6046120.mQ0ExDuKPD@thomas/


Regarding the virtio channel API, Bruce and I had a look at this, and I 
think I need to do some more research into it. I'd prefer not to make 
that API public, as it was intended to be mainly for the 
vm_power_manager app and the companion guest_cli.

So I'll look into this, and look at the best way to proceed with 
cleaning this up so that these apps can be build using meson/ninja as 
part of DPDK, as well as using 'make' extrernal to DPDK.

I hope to push up an RFC next week so we can get agreement on the best 
path forward on this item.


>
> Priority #3: request feedbacks from other maintainers
> to add a generic API in ethdev to get a hook for power management.
>

Would it be possible to look at #2 and #3 in parallel? I'm not sure I'd 
have #2 done fully in time for this release, and, if not, I will make 
sure it's done for 21.02.


Rgds,
Dave.