From 0baedd792713063213f1e2060dc6a5d536638f0a Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Wed, 25 Mar 2020 12:28:24 -0400 Subject: [PATCH] KVM: x86: make Hyper-V PV TLB flush use tlb_flush_guest() Hyper-V PV TLB flush mechanism does TLB flush on behalf of the guest so doing tlb_flush_all() is an overkill, switch to using tlb_flush_guest() (just like KVM PV TLB flush mechanism) instead. Introduce KVM_REQ_HV_TLB_FLUSH to support the change. Signed-off-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/hyperv.c | 3 +-- arch/x86/kvm/x86.c | 10 +++++++++- 3 files changed, 12 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index a7c1ea1..9951b01 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -83,6 +83,8 @@ #define KVM_REQ_GET_VMCS12_PAGES KVM_ARCH_REQ(24) #define KVM_REQ_APICV_UPDATE \ KVM_ARCH_REQ_FLAGS(25, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) +#define KVM_REQ_HV_TLB_FLUSH \ + KVM_ARCH_REQ_FLAGS(26, KVM_REQUEST_NO_WAKEUP) #define CR0_RESERVED_BITS \ (~(unsigned long)(X86_CR0_PE | X86_CR0_MP | X86_CR0_EM | X86_CR0_TS \ diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index bcefa9d..b850f67 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1425,8 +1425,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa, * vcpu->arch.cr3 may not be up-to-date for running vCPUs so we can't * analyze it here, flush TLB regardless of the specified address space. */ - kvm_make_vcpus_request_mask(kvm, - KVM_REQ_TLB_FLUSH | KVM_REQUEST_NO_WAKEUP, + kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask, &hv_vcpu->tlb_flush); ret_success: diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c7ad142..a7df68a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2696,6 +2696,12 @@ static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa) kvm_x86_ops.tlb_flush(vcpu, invalidate_gpa); } +static void kvm_vcpu_flush_tlb_guest(struct kvm_vcpu *vcpu) +{ + ++vcpu->stat.tlb_flush; + kvm_x86_ops.tlb_flush_guest(vcpu); +} + static void record_steal_time(struct kvm_vcpu *vcpu) { struct kvm_host_map map; @@ -2719,7 +2725,7 @@ static void record_steal_time(struct kvm_vcpu *vcpu) trace_kvm_pv_tlb_flush(vcpu->vcpu_id, st->preempted & KVM_VCPU_FLUSH_TLB); if (xchg(&st->preempted, 0) & KVM_VCPU_FLUSH_TLB) - kvm_x86_ops.tlb_flush_guest(vcpu); + kvm_vcpu_flush_tlb_guest(vcpu); vcpu->arch.st.preempted = 0; @@ -8218,6 +8224,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) kvm_mmu_load_pgd(vcpu); if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) kvm_vcpu_flush_tlb(vcpu, true); + if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu)) + kvm_vcpu_flush_tlb_guest(vcpu); if (kvm_check_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu)) { vcpu->run->exit_reason = KVM_EXIT_TPR_ACCESS; r = 0; -- 2.7.4