From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vitaly Kuznetsov Subject: [PATCH v2 0/5] Enlightened VMCS support for KVM on Hyper-V Date: Mon, 26 Feb 2018 18:11:16 +0100 Message-ID: <20180226171121.18974-1-vkuznets@redhat.com> Cc: x86@kernel.org, Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , "Michael Kelley (EOSG)" , Mohammed Gamal , Cathy Avery , Bandan Das , linux-kernel@vger.kernel.org To: kvm@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Changes since v1: - The only comment I got for v1 was from kbuild test robot. The issue was addressed by moving HV_X64_ENLIGHTENED_VMCS_RECOMMENDED definition to PATCH2. - Rebased to current kvm/queue. When running nested KVM on Hyper-V it's possible to use so called 'Enlightened VMCS' and do normal memory reads/writes instead of doing VMWRITE/VMREAD instructions. In addition, clean field mask provides a huge room for optimization on L0's side. Tight CPUID loop test shows significant speedup (current kvm/queue on E5-2667 v4 @ 3.20GHz): Before: 20766 cycles After: 8912 cycles The series is based on current kvm/queue tree. Ladi Prosek (1): x86/kvm: rename HV_X64_MSR_APIC_ASSIST_PAGE to HV_X64_MSR_VP_ASSIST_PAGE Vitaly Kuznetsov (4): x86/hyper-v: allocate and use Virtual Processor Assist Pages x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits x86/hyper-v: detect nested features x86/kvm: use Enlightened VMCS when running on Hyper-V arch/x86/hyperv/hv_init.c | 33 +++ arch/x86/include/asm/mshyperv.h | 12 + arch/x86/include/uapi/asm/hyperv.h | 223 ++++++++++++++- arch/x86/kernel/cpu/mshyperv.c | 3 + arch/x86/kvm/hyperv.c | 8 +- arch/x86/kvm/lapic.h | 2 +- arch/x86/kvm/vmx.c | 561 ++++++++++++++++++++++++++++++++++++- arch/x86/kvm/x86.c | 2 +- 8 files changed, 825 insertions(+), 19 deletions(-) -- 2.14.3