Starting with Zen4, core PMU on AMD platforms such as Genoa and Ryzen-7000 will support PerfMonV2, and it is also compatible with legacy PERFCTR_CORE behavior and MSR addresses. If you don't have access to the hardware specification, the commits d6d0c7f681fd..7685665c390d for host perf can also bring a quick overview. Its main change is the addition of three MSR's equivalent to Intel V2, namely global_ctrl, global_status, global_status_clear. It is worth noting that this feature is very attractive for reducing the overhead of PMU virtualization, since multiple MSR accesses to multiple counters will be replaced by a single access to the global register, plus more accuracy gain when multiple guest counters are used. All related testcases are passed on a Genoa box. Please feel free to run more tests, add more or share comments. Patch 0001-0007 could be applied earlier, which may help reduce the burden on industrious reviewers. Previous: https://lore.kernel.org/kvm/20230214050757.9623-1-likexu@xxxxxxxxxxx/ V5 -> V6 Changelog: - Introduce pmu_ops->MIN_NR_GP_COUNTERS and WARN_ON_ONCE; (Sean) - Set MIN_NR_GP_COUNTERS = 2 instead of 1 for Intel Arch PMU; Like Xu (10): KVM: x86/pmu: Expose reprogram_counters() in pmu.h KVM: x86/pmu: Return #GP if user sets the GLOBAL_STATUS reserved bits KVM: x86/pmu: Make part of the Intel v2 PMU MSRs handling x86 generic KVM: x86: Explicitly zero cpuid "0xa" leaf when PMU is disabled KVM: x86/pmu: Disable vPMU if the minimum num of counters isn't met KVM: x86/pmu: Forget PERFCTR_CORE if the min num of counters isn't met KVM: x86/pmu: Constrain the num of guest counters with kvm_pmu_cap KVM: x86/cpuid: Add a KVM-only leaf to redirect AMD PerfMonV2 flag KVM: x86/svm/pmu: Add AMD PerfMonV2 support KVM: x86/cpuid: Add AMD CPUID ExtPerfMonAndDbg leaf 0x80000022 arch/x86/include/asm/kvm-x86-pmu-ops.h | 1 - arch/x86/kvm/cpuid.c | 30 +++++++++- arch/x86/kvm/pmu.c | 83 +++++++++++++++++++++++--- arch/x86/kvm/pmu.h | 43 +++++++++++-- arch/x86/kvm/reverse_cpuid.h | 7 +++ arch/x86/kvm/svm/pmu.c | 68 +++++++++++++++------ arch/x86/kvm/svm/svm.c | 19 +++++- arch/x86/kvm/vmx/pmu_intel.c | 33 +++------- arch/x86/kvm/x86.c | 10 ++++ 9 files changed, 230 insertions(+), 64 deletions(-) base-commit: b9846a698c9aff4eb2214a06ac83638ad098f33f -- 2.40.1
