From 80154d77c922d0f9bb1e4d115ff760c066c12d8f Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 24 Aug 2017 13:55:35 +0200 Subject: [PATCH] KVM: VMX: cache secondary exec controls Currently, secondary execution controls are divided in three groups: - static, depending mostly on the module arguments or the processor (vmx_secondary_exec_control) - static, depending on CPUID (vmx_cpuid_update) - dynamic, depending on nested VMX or local APIC state Because walking CPUID is expensive, prepare_vmcs02 is using only the first group. This however is unnecessarily complicated. Just cache the static secondary execution controls, and then prepare_vmcs02 does not need to compute them every time. Computation of all static secondary execution controls is now kept in a single function, vmx_compute_secondary_exec_control. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx.c | 100 ++++++++++++++++++++++++--------------------- 1 file changed, 54 insertions(+), 46 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 19aa69af7c2d..08381a5d8879 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -576,6 +576,8 @@ struct vcpu_vmx { #endif u32 vm_entry_controls_shadow; u32 vm_exit_controls_shadow; + u32 secondary_exec_control; + /* * loaded_vmcs points to the VMCS currently used in this vcpu. For a * non-nested (L1) guest, it always points to vmcs01. For a nested @@ -2807,7 +2809,10 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx) vmx->nested.nested_vmx_procbased_ctls_low &= ~(CPU_BASED_CR3_LOAD_EXITING | CPU_BASED_CR3_STORE_EXITING); - /* secondary cpu-based controls */ + /* + * secondary cpu-based controls. Do not include those that + * depend on CPUID bits, they are added later by vmx_cpuid_update. + */ rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2, vmx->nested.nested_vmx_secondary_ctls_low, vmx->nested.nested_vmx_secondary_ctls_high); @@ -2815,7 +2820,6 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx) vmx->nested.nested_vmx_secondary_ctls_high &= SECONDARY_EXEC_RDRAND | SECONDARY_EXEC_RDSEED | SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES | - SECONDARY_EXEC_RDTSCP | SECONDARY_EXEC_DESC | SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE | SECONDARY_EXEC_APIC_REGISTER_VIRT | @@ -5269,10 +5273,12 @@ static u32 vmx_exec_control(struct vcpu_vmx *vmx) return exec_control; } -static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx) +static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx) { + struct kvm_vcpu *vcpu = &vmx->vcpu; + u32 exec_control = vmcs_config.cpu_based_2nd_exec_ctrl; - if (!cpu_need_virtualize_apic_accesses(&vmx->vcpu)) + if (!cpu_need_virtualize_apic_accesses(vcpu)) exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES; if (vmx->vpid == 0) exec_control &= ~SECONDARY_EXEC_ENABLE_VPID; @@ -5286,7 +5292,7 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx) exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST; if (!ple_gap) exec_control &= ~SECONDARY_EXEC_PAUSE_LOOP_EXITING; - if (!kvm_vcpu_apicv_active(&vmx->vcpu)) + if (!kvm_vcpu_apicv_active(vcpu)) exec_control &= ~(SECONDARY_EXEC_APIC_REGISTER_VIRT | SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY); exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE; @@ -5300,7 +5306,43 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx) if (!enable_pml) exec_control &= ~SECONDARY_EXEC_ENABLE_PML; - return exec_control; + if (vmx_rdtscp_supported()) { + bool rdtscp_enabled = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP); + if (!rdtscp_enabled) + exec_control &= ~SECONDARY_EXEC_RDTSCP; + + if (nested) { + if (rdtscp_enabled) + vmx->nested.nested_vmx_secondary_ctls_high |= + SECONDARY_EXEC_RDTSCP; + else + vmx->nested.nested_vmx_secondary_ctls_high &= + ~SECONDARY_EXEC_RDTSCP; + } + } + + if (vmx_invpcid_supported()) { + /* Exposing INVPCID only when PCID is exposed */ + bool invpcid_enabled = + guest_cpuid_has(vcpu, X86_FEATURE_INVPCID) && + guest_cpuid_has(vcpu, X86_FEATURE_PCID); + + if (!invpcid_enabled) { + exec_control &= ~SECONDARY_EXEC_ENABLE_INVPCID; + guest_cpuid_clear(vcpu, X86_FEATURE_INVPCID); + } + + if (nested) { + if (invpcid_enabled) + vmx->nested.nested_vmx_secondary_ctls_high |= + SECONDARY_EXEC_ENABLE_INVPCID; + else + vmx->nested.nested_vmx_secondary_ctls_high &= + ~SECONDARY_EXEC_ENABLE_INVPCID; + } + } + + vmx->secondary_exec_control = exec_control; } static void ept_set_mmio_spte_mask(void) @@ -5344,8 +5386,9 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx) vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, vmx_exec_control(vmx)); if (cpu_has_secondary_exec_ctrls()) { + vmx_compute_secondary_exec_control(vmx); vmcs_write32(SECONDARY_VM_EXEC_CONTROL, - vmx_secondary_exec_control(vmx)); + vmx->secondary_exec_control); } if (kvm_vcpu_apicv_active(&vmx->vcpu)) { @@ -9623,47 +9666,12 @@ static void nested_vmx_cr_fixed1_bits_update(struct kvm_vcpu *vcpu) static void vmx_cpuid_update(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); - u32 secondary_exec_ctl = vmx_secondary_exec_control(vmx); - - if (vmx_rdtscp_supported()) { - bool rdtscp_enabled = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP); - if (!rdtscp_enabled) - secondary_exec_ctl &= ~SECONDARY_EXEC_RDTSCP; - - if (nested) { - if (rdtscp_enabled) - vmx->nested.nested_vmx_secondary_ctls_high |= - SECONDARY_EXEC_RDTSCP; - else - vmx->nested.nested_vmx_secondary_ctls_high &= - ~SECONDARY_EXEC_RDTSCP; - } - } - - if (vmx_invpcid_supported()) { - /* Exposing INVPCID only when PCID is exposed */ - bool invpcid_enabled = - guest_cpuid_has(vcpu, X86_FEATURE_INVPCID) && - guest_cpuid_has(vcpu, X86_FEATURE_PCID); - - if (!invpcid_enabled) { - secondary_exec_ctl &= ~SECONDARY_EXEC_ENABLE_INVPCID; - guest_cpuid_clear(vcpu, X86_FEATURE_INVPCID); - } - if (nested) { - if (invpcid_enabled) - vmx->nested.nested_vmx_secondary_ctls_high |= - SECONDARY_EXEC_ENABLE_INVPCID; - else - vmx->nested.nested_vmx_secondary_ctls_high &= - ~SECONDARY_EXEC_ENABLE_INVPCID; - } + if (cpu_has_secondary_exec_ctrls()) { + vmx_compute_secondary_exec_control(vmx); + vmcs_set_secondary_exec_control(vmx->secondary_exec_control); } - if (cpu_has_secondary_exec_ctrls()) - vmcs_set_secondary_exec_control(secondary_exec_ctl); - if (nested_vmx_allowed(vcpu)) to_vmx(vcpu)->msr_ia32_feature_control_valid_bits |= FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX; @@ -10356,7 +10364,7 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, enable_ept ? vmcs12->page_fault_error_code_match : 0); if (cpu_has_secondary_exec_ctrls()) { - exec_control = vmx_secondary_exec_control(vmx); + exec_control = vmx->secondary_exec_control; /* Take the following fields only from vmcs12 */ exec_control &= ~(SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES | -- 2.20.1