Re: [PATCH v4 01/16] perf/x86/intel: Add x86_pmu.pebs_vmx for Ice Lake Servers

[Andi Kleen]

> AFAIK， Icelake supports adaptive PEBS and extended PEBS which Skylake
> doesn't.
> But we can still use IA32_PEBS_ENABLE MSR to indicate general-purpose
> counter in Skylake.
> Is there anything else that only Icelake supports in this patches set?

Only Icelake server has the support for recovering from a EPT violation
on the PEBS data structures. To use it on Skylake server you would
need to pin the whole guest, but that is currently not done.

> Besides, we have tried this patches set in Icelake.  We can use pebs(eg:
> "perf record -e cycles:pp")
> when guest is kernel-5.11, but can't when kernel-4.18.  Is there a minimum
> guest kernel version requirement?

You would need a guest kernel that supports Icelake server PEBS. 4.18
would need backports for tht.


-Andi