Hi Paolo, On 2020/5/14 16:30, Like Xu wrote:
Hi Peter, Would you mind acking the host perf patches if it looks good to you ? Hi Paolo, Please help review the KVM proposal changes in this stable version. Now, we can use upstream QEMU w/ '-cpu host' to test this feature, and disable it by clearing the LBR format bits in the IA32_PERF_CAPABILITIES. v10->v11 Changelog: - add '.config = INTEL_FIXED_VLBR_EVENT' to the guest LBR event config; - rewrite is_guest_lbr_event() with 'config == INTEL_FIXED_VLBR_EVENT'; - emit pr_warn() on the host when guest LBR is temporarily unavailable; - drop the KVM_CAP_X86_GUEST_LBR patch; - rewrite MSR_IA32_PERF_CAPABILITIES patch LBR record format; - split 'kvm_pmu->lbr_already_available' into a separate patch; - split 'pmu_ops->availability_check' into a separate patch; - comments and naming refinement, misc; You may check more details in each commit. Previous: https://lore.kernel.org/kvm/20200423081412.164863-1-like.xu@xxxxxxxxxxxxxxx/
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Like Xu (9): perf/x86/core: Refactor hw->idx checks and cleanup perf/x86/lbr: Add interface to get basic information about LBR stack perf/x86: Add constraint to create guest LBR event without hw counter perf/x86: Keep LBR stack unchanged in host context for guest LBR event
Do you have a moment to review the KVM changes in this version to enable guest LBR on most Intel platforms ? It would be great if I can address most of your comments in the next version. Thanks, Like Xu
KVM: x86: Expose MSR_IA32_PERF_CAPABILITIES for LBR record format KVM: x86/pmu: Emulate LBR feature via guest LBR event KVM: x86/pmu: Release guest LBR event via vPMU lazy release mechanism KVM: x86/pmu: Check guest LBR availability in case host reclaims them KVM: x86/pmu: Reduce the overhead of LBR passthrough or cancellation Wei Wang (2): perf/x86: Fix variable types for LBR registers KVM: x86/pmu: Tweak kvm_pmu_get_msr to pass 'struct msr_data' in arch/x86/events/core.c | 26 ++- arch/x86/events/intel/core.c | 105 ++++++---- arch/x86/events/intel/lbr.c | 56 +++++- arch/x86/events/perf_event.h | 12 +- arch/x86/include/asm/kvm_host.h | 13 ++ arch/x86/include/asm/perf_event.h | 34 +++- arch/x86/kvm/cpuid.c | 2 +- arch/x86/kvm/pmu.c | 19 +- arch/x86/kvm/pmu.h | 15 +- arch/x86/kvm/svm/pmu.c | 7 +- arch/x86/kvm/vmx/capabilities.h | 15 ++ arch/x86/kvm/vmx/pmu_intel.c | 320 +++++++++++++++++++++++++++++- arch/x86/kvm/vmx/vmx.c | 12 +- arch/x86/kvm/vmx/vmx.h | 2 + arch/x86/kvm/x86.c | 18 +- 15 files changed, 564 insertions(+), 92 deletions(-)
