KVM: X86: Reduce the overhead when lapic_timer_advance is disabled

[platform/kernel/linux-rpi.git] / arch / x86 / kvm / x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index eee8e7f..54d66f2 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -794,6 +794,9 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
        if (!guest_cpuid_has(vcpu, X86_FEATURE_LA57) && (cr4 & X86_CR4_LA57))
                return 1;
 
+       if (!guest_cpuid_has(vcpu, X86_FEATURE_UMIP) && (cr4 & X86_CR4_UMIP))
+               return 1;
+
        if (is_long_mode(vcpu)) {
                if (!(cr4 & X86_CR4_PAE))
                        return 1;
@@ -1036,6 +1039,7 @@ static u32 emulated_msrs[] = {
        MSR_IA32_MCG_CTL,
        MSR_IA32_MCG_EXT_CTL,
        MSR_IA32_SMBASE,
+       MSR_SMI_COUNT,
        MSR_PLATFORM_INFO,
        MSR_MISC_FEATURES_ENABLES,
 };
@@ -2228,6 +2232,11 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
                        return 1;
                vcpu->arch.smbase = data;
                break;
+       case MSR_SMI_COUNT:
+               if (!msr_info->host_initiated)
+                       return 1;
+               vcpu->arch.smi_count = data;
+               break;
        case MSR_KVM_WALL_CLOCK_NEW:
        case MSR_KVM_WALL_CLOCK:
                vcpu->kvm->arch.wall_clock = data;
@@ -2502,6 +2511,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
                        return 1;
                msr_info->data = vcpu->arch.smbase;
                break;
+       case MSR_SMI_COUNT:
+               msr_info->data = vcpu->arch.smi_count;
+               break;
        case MSR_IA32_PERF_STATUS:
                /* TSC increment by tick */
                msr_info->data = 1000ULL;
@@ -2937,7 +2949,6 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
        srcu_read_unlock(&vcpu->kvm->srcu, idx);
        pagefault_enable();
        kvm_x86_ops->vcpu_put(vcpu);
-       kvm_put_guest_fpu(vcpu);
        vcpu->arch.last_host_tsc = rdtsc();
 }
 
@@ -5252,17 +5263,6 @@ static void emulator_halt(struct x86_emulate_ctxt *ctxt)
        emul_to_vcpu(ctxt)->arch.halt_request = 1;
 }
 
-static void emulator_get_fpu(struct x86_emulate_ctxt *ctxt)
-{
-       preempt_disable();
-       kvm_load_guest_fpu(emul_to_vcpu(ctxt));
-}
-
-static void emulator_put_fpu(struct x86_emulate_ctxt *ctxt)
-{
-       preempt_enable();
-}
-
 static int emulator_intercept(struct x86_emulate_ctxt *ctxt,
                              struct x86_instruction_info *info,
                              enum x86_intercept_stage stage)
@@ -5340,8 +5340,6 @@ static const struct x86_emulate_ops emulate_ops = {
        .halt                = emulator_halt,
        .wbinvd              = emulator_wbinvd,
        .fix_hypercall       = emulator_fix_hypercall,
-       .get_fpu             = emulator_get_fpu,
-       .put_fpu             = emulator_put_fpu,
        .intercept           = emulator_intercept,
        .get_cpuid           = emulator_get_cpuid,
        .set_nmi_mask        = emulator_set_nmi_mask,
@@ -6462,6 +6460,7 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
                kvm_x86_ops->queue_exception(vcpu);
        } else if (vcpu->arch.smi_pending && !is_smm(vcpu) && kvm_x86_ops->smi_allowed(vcpu)) {
                vcpu->arch.smi_pending = false;
+               ++vcpu->arch.smi_count;
                enter_smm(vcpu);
        } else if (vcpu->arch.nmi_pending && kvm_x86_ops->nmi_allowed(vcpu)) {
                --vcpu->arch.nmi_pending;
@@ -6778,6 +6777,20 @@ static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
        kvm_x86_ops->tlb_flush(vcpu);
 }
 
+void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,
+               unsigned long start, unsigned long end)
+{
+       unsigned long apic_address;
+
+       /*
+        * The physical address of apic access page is stored in the VMCS.
+        * Update it when it becomes invalid.
+        */
+       apic_address = gfn_to_hva(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT);
+       if (start <= apic_address && apic_address < end)
+               kvm_make_all_cpus_request(kvm, KVM_REQ_APIC_PAGE_RELOAD);
+}
+
 void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
 {
        struct page *page = NULL;
@@ -6952,7 +6965,6 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
        preempt_disable();
 
        kvm_x86_ops->prepare_guest_switch(vcpu);
-       kvm_load_guest_fpu(vcpu);
 
        /*
         * Disable IRQs before setting IN_GUEST_MODE.  Posted interrupt
@@ -7006,7 +7018,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
        }
 
        trace_kvm_entry(vcpu->vcpu_id);
-       wait_lapic_expire(vcpu);
+       if (lapic_timer_advance_ns)
+               wait_lapic_expire(vcpu);
        guest_enter_irqoff();
 
        if (unlikely(vcpu->arch.switch_db_regs)) {
@@ -7265,13 +7278,12 @@ static int complete_emulated_mmio(struct kvm_vcpu *vcpu)
 
 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 {
-       struct fpu *fpu = &current->thread.fpu;
        int r;
 
-       fpu__initialize(fpu);
-
        kvm_sigset_activate(vcpu);
 
+       kvm_load_guest_fpu(vcpu);
+
        if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) {
                if (kvm_run->immediate_exit) {
                        r = -EINTR;
@@ -7312,6 +7324,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                r = vcpu_run(vcpu);
 
 out:
+       kvm_put_guest_fpu(vcpu);
        post_kvm_run_save(vcpu);
        kvm_sigset_deactivate(vcpu);
 
@@ -7381,7 +7394,7 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 #endif
 
        kvm_rip_write(vcpu, regs->rip);
-       kvm_set_rflags(vcpu, regs->rflags);
+       kvm_set_rflags(vcpu, regs->rflags | X86_EFLAGS_FIXED);
 
        vcpu->arch.exception.pending = false;
 
@@ -7704,32 +7717,25 @@ static void fx_init(struct kvm_vcpu *vcpu)
        vcpu->arch.cr0 |= X86_CR0_ET;
 }
 
+/* Swap (qemu) user FPU context for the guest FPU context. */
 void kvm_load_guest_fpu(struct kvm_vcpu *vcpu)
 {
-       if (vcpu->guest_fpu_loaded)
-               return;
-
-       /*
-        * Restore all possible states in the guest,
-        * and assume host would use all available bits.
-        * Guest xcr0 would be loaded later.
-        */
-       vcpu->guest_fpu_loaded = 1;
-       __kernel_fpu_begin();
+       preempt_disable();
+       copy_fpregs_to_fpstate(&vcpu->arch.user_fpu);
        /* PKRU is separately restored in kvm_x86_ops->run.  */
        __copy_kernel_to_fpregs(&vcpu->arch.guest_fpu.state,
                                ~XFEATURE_MASK_PKRU);
+       preempt_enable();
        trace_kvm_fpu(1);
 }
 
+/* When vcpu_run ends, restore user space FPU context. */
 void kvm_put_guest_fpu(struct kvm_vcpu *vcpu)
 {
-       if (!vcpu->guest_fpu_loaded)
-               return;
-
-       vcpu->guest_fpu_loaded = 0;
+       preempt_disable();
        copy_fpregs_to_fpstate(&vcpu->arch.guest_fpu);
-       __kernel_fpu_end();
+       copy_kernel_to_fpregs(&vcpu->arch.user_fpu.state);
+       preempt_enable();
        ++vcpu->stat.fpu_reload;
        trace_kvm_fpu(0);
 }
@@ -7813,6 +7819,7 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
        vcpu->arch.hflags = 0;
 
        vcpu->arch.smi_pending = 0;
+       vcpu->arch.smi_count = 0;
        atomic_set(&vcpu->arch.nmi_queued, 0);
        vcpu->arch.nmi_pending = 0;
        vcpu->arch.nmi_injected = false;
@@ -7846,7 +7853,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
                 * To avoid have the INIT path from kvm_apic_has_events() that be
                 * called with loaded FPU and does not let userspace fix the state.
                 */
-               kvm_put_guest_fpu(vcpu);
+               if (init_event)
+                       kvm_put_guest_fpu(vcpu);
                mpx_state_buffer = get_xsave_addr(&vcpu->arch.guest_fpu.state.xsave,
                                        XFEATURE_MASK_BNDREGS);
                if (mpx_state_buffer)
@@ -7855,6 +7863,8 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
                                        XFEATURE_MASK_BNDCSR);
                if (mpx_state_buffer)
                        memset(mpx_state_buffer, 0, sizeof(struct mpx_bndcsr));
+               if (init_event)
+                       kvm_load_guest_fpu(vcpu);
        }
 
        if (!init_event) {