KVM: x86: optimize steal time calculation

[karo-tx-linux.git] / arch / x86 / kvm / x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 742d0f7d3556e143e219c4ea474e85605be33cde..96e81d284deb36d58d62410f7bf940f4b7f6583c 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -700,7 +700,6 @@ static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
                if ((xcr0 & XFEATURE_MASK_AVX512) != XFEATURE_MASK_AVX512)
                        return 1;
        }
-       kvm_put_guest_xcr0(vcpu);
        vcpu->arch.xcr0 = xcr0;
 
        if ((xcr0 ^ old_xcr0) & XFEATURE_MASK_EXTEND)
@@ -2003,22 +2002,8 @@ static void kvmclock_reset(struct kvm_vcpu *vcpu)
        vcpu->arch.pv_time_enabled = false;
 }
 
-static void accumulate_steal_time(struct kvm_vcpu *vcpu)
-{
-       u64 delta;
-
-       if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
-               return;
-
-       delta = current->sched_info.run_delay - vcpu->arch.st.last_steal;
-       vcpu->arch.st.last_steal = current->sched_info.run_delay;
-       vcpu->arch.st.accum_steal = delta;
-}
-
 static void record_steal_time(struct kvm_vcpu *vcpu)
 {
-       accumulate_steal_time(vcpu);
-
        if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
                return;
 
@@ -2026,9 +2011,10 @@ static void record_steal_time(struct kvm_vcpu *vcpu)
                &vcpu->arch.st.steal, sizeof(struct kvm_steal_time))))
                return;
 
-       vcpu->arch.st.steal.steal += vcpu->arch.st.accum_steal;
+       vcpu->arch.st.steal.steal += current->sched_info.run_delay -
+               vcpu->arch.st.last_steal;
+       vcpu->arch.st.last_steal = current->sched_info.run_delay;
        vcpu->arch.st.steal.version += 2;
-       vcpu->arch.st.accum_steal = 0;
 
        kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.st.stime,
                &vcpu->arch.st.steal, sizeof(struct kvm_steal_time));
@@ -6095,12 +6081,10 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
        }
 
        /* try to inject new event if pending */
-       if (vcpu->arch.nmi_pending) {
-               if (kvm_x86_ops->nmi_allowed(vcpu)) {
-                       --vcpu->arch.nmi_pending;
-                       vcpu->arch.nmi_injected = true;
-                       kvm_x86_ops->set_nmi(vcpu);
-               }
+       if (vcpu->arch.nmi_pending && kvm_x86_ops->nmi_allowed(vcpu)) {
+               --vcpu->arch.nmi_pending;
+               vcpu->arch.nmi_injected = true;
+               kvm_x86_ops->set_nmi(vcpu);
        } else if (kvm_cpu_has_injectable_intr(vcpu)) {
                /*
                 * Because interrupts can be injected asynchronously, we are
@@ -6569,10 +6553,12 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
                if (inject_pending_event(vcpu, req_int_win) != 0)
                        req_immediate_exit = true;
                /* enable NMI/IRQ window open exits if needed */
-               else if (vcpu->arch.nmi_pending)
-                       kvm_x86_ops->enable_nmi_window(vcpu);
-               else if (kvm_cpu_has_injectable_intr(vcpu) || req_int_win)
-                       kvm_x86_ops->enable_irq_window(vcpu);
+               else {
+                       if (vcpu->arch.nmi_pending)
+                               kvm_x86_ops->enable_nmi_window(vcpu);
+                       if (kvm_cpu_has_injectable_intr(vcpu) || req_int_win)
+                               kvm_x86_ops->enable_irq_window(vcpu);
+               }
 
                if (kvm_lapic_enabled(vcpu)) {
                        update_cr8_intercept(vcpu);
@@ -6590,8 +6576,6 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
        kvm_x86_ops->prepare_guest_switch(vcpu);
        if (vcpu->fpu_active)
                kvm_load_guest_fpu(vcpu);
-       kvm_load_guest_xcr0(vcpu);
-
        vcpu->mode = IN_GUEST_MODE;
 
        srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
@@ -6618,6 +6602,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
                goto cancel_injection;
        }
 
+       kvm_load_guest_xcr0(vcpu);
+
        if (req_immediate_exit)
                smp_send_reschedule(vcpu->cpu);
 
@@ -6667,6 +6653,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
        vcpu->mode = OUTSIDE_GUEST_MODE;
        smp_wmb();
 
+       kvm_put_guest_xcr0(vcpu);
+
        /* Interrupt is enabled by handle_external_intr() */
        kvm_x86_ops->handle_external_intr(vcpu);
 
@@ -7314,7 +7302,6 @@ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu)
         * and assume host would use all available bits.
         * Guest xcr0 would be loaded later.
         */
-       kvm_put_guest_xcr0(vcpu);
        vcpu->guest_fpu_loaded = 1;
        __kernel_fpu_begin();
        __copy_kernel_to_fpregs(&vcpu->arch.guest_fpu.state);
@@ -7323,8 +7310,6 @@ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu)
 
 void kvm_put_guest_fpu(struct kvm_vcpu *vcpu)
 {
-       kvm_put_guest_xcr0(vcpu);
-
        if (!vcpu->guest_fpu_loaded) {
                vcpu->fpu_counter = 0;
                return;