On 2020/6/13 16:09, Like Xu wrote:
Hi all, Please help review this new version for the Kenrel 5.9 release. Now, you may apply the last two qemu-devel patches to the upstream qemu and try the guest LBR feature with '-cpu host' command line. v11->v12 Changelog: - apply "Signed-off-by" form PeterZ and his codes for the perf subsystem; - add validity checks before expose LBR via MSR_IA32_PERF_CAPABILITIES; - refactor MSR_IA32_DEBUGCTLMSR emulation with validity check; - reorder "perf_event_attr" fields according to how they're declared; - replace event_is_oncpu() with "event->state" check; - make LBR emualtion specific to vmx rather than x86 generic; - move pass-through LBR code to vmx.c instead of pmu_intel.c; - add vmx_lbr_en/disable_passthrough layer to make code readable; - rewrite pmu availability check with vmx_passthrough_lbr_msrs(); You may check more details in each commit. Previous: https://lore.kernel.org/kvm/20200514083054.62538-1-like.xu@xxxxxxxxxxxxxxx/ ---
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Wei Wang (1): perf/x86: Fix variable types for LBR registers > Like Xu (10): perf/x86/core: Refactor hw->idx checks and cleanup perf/x86/lbr: Add interface to get LBR information perf/x86: Add constraint to create guest LBR event without hw counter perf/x86: Keep LBR records unchanged in host context for guest usage
Hi Peter, Would you like to add "Acked-by" to the first three perf patches ?
KVM: vmx/pmu: Expose LBR to guest via MSR_IA32_PERF_CAPABILITIES KVM: vmx/pmu: Unmask LBR fields in the MSR_IA32_DEBUGCTLMSR emualtion KVM: vmx/pmu: Pass-through LBR msrs when guest LBR event is scheduled KVM: vmx/pmu: Emulate legacy freezing LBRs on virtual PMI KVM: vmx/pmu: Reduce the overhead of LBR pass-through or cancellation KVM: vmx/pmu: Release guest LBR event via lazy release mechanism
Hi Paolo, Would you like to take a moment to review the KVM part for this feature ? Thanks, Like Xu
Qemu-devel: target/i386: add -cpu,lbr=true support to enable guest LBR arch/x86/events/core.c | 26 +-- arch/x86/events/intel/core.c | 109 ++++++++----- arch/x86/events/intel/lbr.c | 51 +++++- arch/x86/events/perf_event.h | 8 +- arch/x86/include/asm/perf_event.h | 34 +++- arch/x86/kvm/pmu.c | 12 +- arch/x86/kvm/pmu.h | 5 + arch/x86/kvm/vmx/capabilities.h | 23 ++- arch/x86/kvm/vmx/pmu_intel.c | 253 +++++++++++++++++++++++++++++- arch/x86/kvm/vmx/vmx.c | 86 +++++++++- arch/x86/kvm/vmx/vmx.h | 17 ++ arch/x86/kvm/x86.c | 13 -- 12 files changed, 559 insertions(+), 78 deletions(-)
