Re: [PATCH 2/6] tools/xc: Add xc_cpu_policy to the public xenctrl.h header

[Alejandro Vallejo <alejandro.vallejo@xxxxxxxxx>]

On 19/03/2024 17:55, Roger Pau Monné wrote:
> On Tue, Jan 09, 2024 at 03:38:30PM +0000, Alejandro Vallejo wrote:
>> Move struct xc_cpu_policy data structure out of xg_private.h and into
>> the public xenguest.h so it can be used by libxl.
> 
> I will let Andrew comment on this one, IIRC the initial idea was to
> not leak cpu_policy into libxl, and to instead have it as an opaque
> object that libxl can interact with using helpers.

I wrote this a while ago, and can't quite remember why I left this here.
Looking closely I think it's leftover from something else I eventually
turned into its own series[1]. I don't _think_ it's needed for this
series, so I'll just drop it in v2. If everything blows up I'll tell you
why I needed it :)

[1]
https://lore.kernel.org/xen-devel/20240207173957.19811-1-alejandro.vallejo@xxxxxxxxx/

> 
> I haven't looked at followup patches - I assume this is done to
> manipulate the cpuid data more easily from libxl, and ultimately drop
> xc_xend_cpuid?

Yes, we can't drop that altogether because xl exposes an interface
allowing fine-grained manipulation of CPUID/MSR data, but it becomes
minimal. The general idea is to is to stop moving separate buffers
around in tandem and use a single data structure instead whenever possible.

Cheers,
Alejandro