KVM: Lazify fpu activation and deactivation

[safe/jmp/linux-2.6] / arch / x86 / kvm / vmx.c

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index dbcdb55..d11be3f 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -66,7 +66,7 @@ module_param(emulate_invalid_guest_state, bool, S_IRUGO);
 #define KVM_GUEST_CR0_MASK                                             \
        (KVM_GUEST_CR0_MASK_UNRESTRICTED_GUEST | X86_CR0_PG | X86_CR0_PE)
 #define KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST                                \
-       (X86_CR0_WP | X86_CR0_NE | X86_CR0_TS | X86_CR0_MP)
+       (X86_CR0_WP | X86_CR0_NE | X86_CR0_MP)
 #define KVM_VM_CR0_ALWAYS_ON                                           \
        (KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST | X86_CR0_PG | X86_CR0_PE)
 #define KVM_CR4_GUEST_OWNED_BITS                                     \
@@ -579,9 +579,8 @@ static void update_exception_bitmap(struct kvm_vcpu *vcpu)
 {
        u32 eb;
 
-       eb = (1u << PF_VECTOR) | (1u << UD_VECTOR) | (1u << MC_VECTOR);
-       if (!vcpu->fpu_active)
-               eb |= 1u << NM_VECTOR;
+       eb = (1u << PF_VECTOR) | (1u << UD_VECTOR) | (1u << MC_VECTOR)
+               | (1u << NM_VECTOR);
        /*
         * Unconditionally intercept #DB so we can maintain dr6 without
         * reading it every exit.
@@ -595,6 +594,8 @@ static void update_exception_bitmap(struct kvm_vcpu *vcpu)
                eb = ~0;
        if (enable_ept)
                eb &= ~(1u << PF_VECTOR); /* bypass_guest_pf = 0 */
+       if (vcpu->fpu_active)
+               eb &= ~(1u << NM_VECTOR);
        vmcs_write32(EXCEPTION_BITMAP, eb);
 }
 
@@ -806,9 +807,6 @@ static void vmx_fpu_activate(struct kvm_vcpu *vcpu)
 
 static void vmx_fpu_deactivate(struct kvm_vcpu *vcpu)
 {
-       if (!vcpu->fpu_active)
-               return;
-       vcpu->fpu_active = 0;
        vmcs_set_bits(GUEST_CR0, X86_CR0_TS);
        update_exception_bitmap(vcpu);
 }
@@ -1737,8 +1735,6 @@ static void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
        else
                hw_cr0 = (cr0 & ~KVM_GUEST_CR0_MASK) | KVM_VM_CR0_ALWAYS_ON;
 
-       vmx_fpu_deactivate(vcpu);
-
        if (vmx->rmode.vm86_active && (cr0 & X86_CR0_PE))
                enter_pmode(vcpu);
 
@@ -1757,12 +1753,12 @@ static void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
        if (enable_ept)
                ept_update_paging_mode_cr0(&hw_cr0, cr0, vcpu);
 
+       if (!vcpu->fpu_active)
+               hw_cr0 |= X86_CR0_TS;
+
        vmcs_writel(CR0_READ_SHADOW, cr0);
        vmcs_writel(GUEST_CR0, hw_cr0);
        vcpu->arch.cr0 = cr0;
-
-       if (!(cr0 & X86_CR0_TS) || !(cr0 & X86_CR0_PE))
-               vmx_fpu_activate(vcpu);
 }
 
 static u64 construct_eptp(unsigned long root_hpa)
@@ -1793,8 +1789,6 @@ static void vmx_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
 
        vmx_flush_tlb(vcpu);
        vmcs_writel(GUEST_CR3, guest_cr3);
-       if (kvm_read_cr0_bits(vcpu, X86_CR0_PE))
-               vmx_fpu_deactivate(vcpu);
 }
 
 static void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
@@ -3002,11 +2996,9 @@ static int handle_cr(struct kvm_vcpu *vcpu)
                };
                break;
        case 2: /* clts */
-               vmx_fpu_deactivate(vcpu);
                vcpu->arch.cr0 &= ~X86_CR0_TS;
                vmcs_writel(CR0_READ_SHADOW, kvm_read_cr0(vcpu));
                trace_kvm_cr_write(0, kvm_read_cr0(vcpu));
-               vmx_fpu_activate(vcpu);
                skip_emulated_instruction(vcpu);
                return 1;
        case 1: /*mov from cr*/
@@ -4127,6 +4119,7 @@ static struct kvm_x86_ops vmx_x86_ops = {
        .cache_reg = vmx_cache_reg,
        .get_rflags = vmx_get_rflags,
        .set_rflags = vmx_set_rflags,
+       .fpu_deactivate = vmx_fpu_deactivate,
 
        .tlb_flush = vmx_flush_tlb,