From 8df14af42f00a434c492c9964a8095bf59831a45 Mon Sep 17 00:00:00 2001 From: Suravee Suthikulpanit Date: Thu, 14 Nov 2019 14:15:06 -0600 Subject: kvm: x86: Add support for dynamic APICv activation Certain runtime conditions require APICv to be temporary deactivated during runtime. The current implementation only support run-time deactivation of APICv when Hyper-V SynIC is enabled, which is not temporary. In addition, for AMD, when APICv is (de)activated at runtime, all vcpus in the VM have to operate in the same mode. Thus the requesting vcpu must notify the others. So, introduce the following: * A new KVM_REQ_APICV_UPDATE request bit * Interfaces to request all vcpus to update APICv status * A new interface to update APICV-related parameters for each vcpu Signed-off-by: Suravee Suthikulpanit Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'arch/x86/kvm/x86.c') diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 98209b8c18c1..616491c134ae 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -26,6 +26,7 @@ #include "cpuid.h" #include "pmu.h" #include "hyperv.h" +#include "lapic.h" #include #include @@ -8013,6 +8014,40 @@ void kvm_make_scan_ioapic_request(struct kvm *kvm) kvm_make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC); } +void kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu) +{ + if (!lapic_in_kernel(vcpu)) + return; + + vcpu->arch.apicv_active = kvm_apicv_activated(vcpu->kvm); + kvm_apic_update_apicv(vcpu); + kvm_x86_ops->refresh_apicv_exec_ctrl(vcpu); +} +EXPORT_SYMBOL_GPL(kvm_vcpu_update_apicv); + +/* + * NOTE: Do not hold any lock prior to calling this. + * + * In particular, kvm_request_apicv_update() expects kvm->srcu not to be + * locked, because it calls __x86_set_memory_region() which does + * synchronize_srcu(&kvm->srcu). + */ +void kvm_request_apicv_update(struct kvm *kvm, bool activate, ulong bit) +{ + if (activate) { + if (!test_and_clear_bit(bit, &kvm->arch.apicv_inhibit_reasons) || + !kvm_apicv_activated(kvm)) + return; + } else { + if (test_and_set_bit(bit, &kvm->arch.apicv_inhibit_reasons) || + kvm_apicv_activated(kvm)) + return; + } + + kvm_make_all_cpus_request(kvm, KVM_REQ_APICV_UPDATE); +} +EXPORT_SYMBOL_GPL(kvm_request_apicv_update); + static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu) { if (!kvm_apic_present(vcpu)) @@ -8203,6 +8238,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) */ if (kvm_check_request(KVM_REQ_HV_STIMER, vcpu)) kvm_hv_process_stimers(vcpu); + if (kvm_check_request(KVM_REQ_APICV_UPDATE, vcpu)) + kvm_vcpu_update_apicv(vcpu); } if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win) { -- cgit v1.2.3