Re: [PATCH v2 0/6] KVM: x86/pmu: Use binary search to check filtered events

[Paolo Bonzini <pbonzini@redhat.com>]

On 1/14/22 02:21, Jim Mattson wrote:
> This started out as a simple change to sort the (up to 300 element)
> PMU filtered event list and to use binary search rather than linear
> search to see if an event is in the list.
> 
> I thought it would be nice to add a directed test for the PMU event
> filter, and that's when things got complicated. The Intel side was
> fine, but the AMD side was a bit ugly, until I did a few
> refactorings. Imagine my dismay when I discovered that the PMU event
> filter works fine on the AMD side, but that fundamental PMU
> virtualization is broken. And I don't just mean erratum 1292, though
> that throws even more brokenness into the mix.
> 
> v1 -> v2
> * Drop the check for "AMDisbetter!" in is_amd_cpu() [David Dunn]
> * Drop the call to cpuid(0, 0) that fed the original check for
>    CPU vendor string "AuthenticAMD" in vm_compute_max_gfn().
> * Simplify the inline asm in the selftest by using the compound literal
>    for both input & output.

Queued, thanks.

Paolo

> Jim Mattson (6):
>    KVM: x86/pmu: Use binary search to check filtered events
>    selftests: kvm/x86: Parameterize the CPUID vendor string check
>    selftests: kvm/x86: Introduce is_amd_cpu()
>    selftests: kvm/x86: Export x86_family() for use outside of processor.c
>    selftests: kvm/x86: Introduce x86_model()
>    selftests: kvm/x86: Add test for KVM_SET_PMU_EVENT_FILTER
> 
>   arch/x86/kvm/pmu.c                            |  30 +-
>   tools/testing/selftests/kvm/.gitignore        |   1 +
>   tools/testing/selftests/kvm/Makefile          |   1 +
>   .../selftests/kvm/include/x86_64/processor.h  |  18 ++
>   .../selftests/kvm/lib/x86_64/processor.c      |  40 +--
>   .../kvm/x86_64/pmu_event_filter_test.c        | 306 ++++++++++++++++++
>   6 files changed, 361 insertions(+), 35 deletions(-)
>   create mode 100644 tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
>