Re: [Qemu-devel] [PATCH 5/6] qapi: extract CpuInfoCommon to mitigate schema duplication

[Laszlo Ersek]

On 04/25/18 21:12, Eric Blake wrote:
> On 04/25/2018 08:20 AM, Laszlo Ersek wrote:
> 
>> ...
>>
>> and people would ask themselves ever after, "are there some common
>> fields in there that we could extract ... hmmm, @props and @arch, okay,
>> maybe, maybe not, grey area". Let's do it now and save them the thinking.
> 
> No, CpuInfo is slated for death in the next year or so; per commit
> ff9a9156.  Once it disappears (in 2.14 or 2.15?), we will ONLY have
> CpuInfoFast (although we might rename it at that time, as the name of
> QMP structs is not part of the introspection interface).
> 
> So, my personal inclination is to just live with the mindless
> near-duplication until the deprecation period ends, rather than wasting
> cycles refactoring things just to refactor it back out when removing the
> dead code later.
> 

This is an important update; thank you for it. Because, it tells me that
we might not need to add @target to CpuInfo at all. Why *extend* an
interface that is deprecated to the point that we're reluctant even to
*refactor* it?

(BTW, I had noticed the deprecation note in the schema source code, from
what you've now identified as commit ff9a9156; I didn't know what it
meant -- I didn't know it carried a removal sentence.)

The consequence is that I could drop the painful modifications for
qmp_query_cpus() altogether, and just keep the simple ones for
qmp_query_cpus_fast().

Markus, does that work for you? Forget about @CpuInfo for good?

Thanks,
Laszlo