Re: [PATCH 3/3] x86/cpufreq: Drop opencoded CPUID handling from powernow

[Andrew Cooper <amc96@xxxxxxxx>]

On 12/11/2021 18:28, Andrew Cooper wrote:
> Xen already collects CPUID.0x80000007.edx by default, meaning that we can
> refer to per-cpu data directly.  This also avoids the need IPI the onlining
> CPU to identify whether Core Performance Boost is available.
>
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> ---
> CC: Jan Beulich <JBeulich@xxxxxxxx>
> CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
> CC: Wei Liu <wl@xxxxxxx>
>
> I don't think the printk() is very helpful.  I could be talked into retaining
> it as a prink_once(), but (irrespective of cpufreq_verbose), it doesn't want
> repeating on each CPU because it will either be all or none of them.

I should note that the printk() is also false.  Nothing AFAICT
synchronises the software turbo setting with hardware, until the next
time set-turbo is called.

~Andrew