Re: [RESEND v13 00/10] KVM: x86/pmu: Guest Last Branch Recording Enabling

Xu, Like
2021-01-15T08:52:21Z

Hi Alex,

Thank you for trying this guest feature on multiple Intel platforms!
If you have more specific comments or any concerns, just let me know.

---
thx, likexu

On 2021/1/15 16:19, Alex Shi wrote:
>
> 在 2021/1/8 上午9:36, Like Xu 写道:
>> Because saving/restoring tens of LBR MSRs (e.g. 32 LBR stack entries) in
>> VMX transition brings too excessive overhead to frequent vmx transition
>> itself, the guest LBR event would help save/restore the LBR stack msrs
>> during the context switching with the help of native LBR event callstack
>> mechanism, including LBR_SELECT msr.
>>
> Sounds the feature is much helpful for VMM guest performance tunning.
> Good job!
>
> Thanks
> Alex