diff options
author | Wanpeng Li <wanpengli@tencent.com> | 2018-03-12 04:53:04 -0700 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2018-03-16 22:03:53 +0100 |
commit | b31c114b82b2b55913d2cf744e6a665c2ca090ac (patch) | |
tree | 56aabff42789a37caea34841c397c5caf066bd34 /arch/x86/kvm | |
parent | caa057a2cad647fb368a12c8e6c410ac4c28e063 (diff) |
KVM: X86: Provide a capability to disable PAUSE intercepts
Allow to disable pause loop exit/pause filtering on a per VM basis.
If some VMs have dedicated host CPUs, they won't be negatively affected
due to needlessly intercepted PAUSE instructions.
Thanks to Jan H. Schönherr's initial patch.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
-rw-r--r-- | arch/x86/kvm/svm.c | 3 | ||||
-rw-r--r-- | arch/x86/kvm/vmx.c | 17 | ||||
-rw-r--r-- | arch/x86/kvm/x86.c | 4 | ||||
-rw-r--r-- | arch/x86/kvm/x86.h | 9 |
4 files changed, 26 insertions, 7 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 0f801d82f493..9729b7e59cc9 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1460,7 +1460,8 @@ static void init_vmcb(struct vcpu_svm *svm) svm->nested.vmcb = 0; svm->vcpu.arch.hflags = 0; - if (boot_cpu_has(X86_FEATURE_PAUSEFILTER)) { + if (boot_cpu_has(X86_FEATURE_PAUSEFILTER) && + !kvm_pause_in_guest(svm->vcpu.kvm)) { control->pause_filter_count = 3000; set_intercept(svm, INTERCEPT_PAUSE); } diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 65747d1194ac..12473e769b0d 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5595,7 +5595,7 @@ static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx) } if (!enable_unrestricted_guest) exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST; - if (!ple_gap) + if (kvm_pause_in_guest(vmx->vcpu.kvm)) exec_control &= ~SECONDARY_EXEC_PAUSE_LOOP_EXITING; if (!kvm_vcpu_apicv_active(vcpu)) exec_control &= ~(SECONDARY_EXEC_APIC_REGISTER_VIRT | @@ -5758,7 +5758,7 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx) vmcs_write64(POSTED_INTR_DESC_ADDR, __pa((&vmx->pi_desc))); } - if (ple_gap) { + if (!kvm_pause_in_guest(vmx->vcpu.kvm)) { vmcs_write32(PLE_GAP, ple_gap); vmx->ple_window = ple_window; vmx->ple_window_dirty = true; @@ -7207,7 +7207,7 @@ static __exit void hardware_unsetup(void) */ static int handle_pause(struct kvm_vcpu *vcpu) { - if (ple_gap) + if (!kvm_pause_in_guest(vcpu->kvm)) grow_ple_window(vcpu); /* @@ -9903,6 +9903,13 @@ free_vcpu: return ERR_PTR(err); } +static int vmx_vm_init(struct kvm *kvm) +{ + if (!ple_gap) + kvm->arch.pause_in_guest = true; + return 0; +} + static void __init vmx_check_processor_compat(void *rtn) { struct vmcs_config vmcs_conf; @@ -12052,7 +12059,7 @@ static void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu) static void vmx_sched_in(struct kvm_vcpu *vcpu, int cpu) { - if (ple_gap) + if (!kvm_pause_in_guest(vcpu->kvm)) shrink_ple_window(vcpu); } @@ -12412,6 +12419,8 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = { .cpu_has_accelerated_tpr = report_flexpriority, .cpu_has_high_real_mode_segbase = vmx_has_high_real_mode_segbase, + .vm_init = vmx_vm_init, + .vcpu_create = vmx_create_vcpu, .vcpu_free = vmx_free_vcpu, .vcpu_reset = vmx_vcpu_reset, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 9e6aaf62bf3c..26a8cd93be0c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2878,7 +2878,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = KVM_CLOCK_TSC_STABLE; break; case KVM_CAP_X86_DISABLE_EXITS: - r |= KVM_X86_DISABLE_EXITS_HTL; + r |= KVM_X86_DISABLE_EXITS_HTL | KVM_X86_DISABLE_EXITS_PAUSE; if(kvm_can_mwait_in_guest()) r |= KVM_X86_DISABLE_EXITS_MWAIT; break; @@ -4235,6 +4235,8 @@ split_irqchip_unlock: kvm->arch.mwait_in_guest = true; if (cap->args[0] & KVM_X86_DISABLE_EXITS_HTL) kvm->arch.hlt_in_guest = true; + if (cap->args[0] & KVM_X86_DISABLE_EXITS_PAUSE) + kvm->arch.pause_in_guest = true; r = 0; break; default: diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 6d14589c1a91..b620cfa8e8d5 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -266,8 +266,10 @@ static inline u64 nsec_to_cycles(struct kvm_vcpu *vcpu, u64 nsec) #define KVM_X86_DISABLE_EXITS_MWAIT (1 << 0) #define KVM_X86_DISABLE_EXITS_HTL (1 << 1) +#define KVM_X86_DISABLE_EXITS_PAUSE (1 << 2) #define KVM_X86_DISABLE_VALID_EXITS (KVM_X86_DISABLE_EXITS_MWAIT | \ - KVM_X86_DISABLE_EXITS_HTL) + KVM_X86_DISABLE_EXITS_HTL | \ + KVM_X86_DISABLE_EXITS_PAUSE) static inline bool kvm_mwait_in_guest(struct kvm *kvm) { @@ -279,4 +281,9 @@ static inline bool kvm_hlt_in_guest(struct kvm *kvm) return kvm->arch.hlt_in_guest; } +static inline bool kvm_pause_in_guest(struct kvm *kvm) +{ + return kvm->arch.pause_in_guest; +} + #endif |