[PATCH 33/43] KVM: VMX: Shadow VMCS pin controls

From: Paolo Bonzini
Date: Thu Jun 13 2019 - 13:10:29 EST


From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>

Prepare to shadow all major control fields on a per-VMCS basis, which
allows KVM to avoid costly VMWRITEs when switching between vmcs01 and
vmcs02.

Shadowing pin controls also allows a future patch to remove the per-VMCS
'hv_timer_armed' flag, as the shadow copy is a superset of said flag.

Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/vmx/nested.c | 3 ++-
arch/x86/kvm/vmx/vmx.c | 10 ++++------
arch/x86/kvm/vmx/vmx.h | 2 ++
3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index f5612b475393..0179ac083dd1 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -285,6 +285,7 @@ static void vmx_switch_vmcs(struct kvm_vcpu *vcpu, struct loaded_vmcs *vmcs)

vm_entry_controls_reset_shadow(vmx);
vm_exit_controls_reset_shadow(vmx);
+ pin_controls_reset_shadow(vmx);
vmx_segment_cache_clear(vmx);
}

@@ -2026,7 +2027,7 @@ static void prepare_vmcs02_early(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12)
} else {
exec_control &= ~PIN_BASED_POSTED_INTR;
}
- vmcs_write32(PIN_BASED_VM_EXEC_CONTROL, exec_control);
+ pin_controls_init(vmx, exec_control);

/*
* EXEC CONTROLS
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 91e43c03144d..6eb4063d98fc 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -3844,7 +3844,7 @@ static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);

- vmcs_write32(PIN_BASED_VM_EXEC_CONTROL, vmx_pin_based_exec_ctrl(vmx));
+ pin_controls_set(vmx, vmx_pin_based_exec_ctrl(vmx));
if (cpu_has_secondary_exec_ctrls()) {
if (kvm_vcpu_apicv_active(vcpu))
vmcs_set_bits(SECONDARY_VM_EXEC_CONTROL,
@@ -4042,7 +4042,7 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx)
vmcs_write64(VMCS_LINK_POINTER, -1ull); /* 22.3.1.5 */

/* Control */
- vmcs_write32(PIN_BASED_VM_EXEC_CONTROL, vmx_pin_based_exec_ctrl(vmx));
+ pin_controls_init(vmx, vmx_pin_based_exec_ctrl(vmx));
vmx->hv_deadline_tsc = -1;

vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, vmx_exec_control(vmx));
@@ -6366,8 +6366,7 @@ static void vmx_arm_hv_timer(struct vcpu_vmx *vmx, u32 val)
{
vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, val);
if (!vmx->loaded_vmcs->hv_timer_armed)
- vmcs_set_bits(PIN_BASED_VM_EXEC_CONTROL,
- PIN_BASED_VMX_PREEMPTION_TIMER);
+ pin_controls_setbit(vmx, PIN_BASED_VMX_PREEMPTION_TIMER);
vmx->loaded_vmcs->hv_timer_armed = true;
}

@@ -6396,8 +6395,7 @@ static void vmx_update_hv_timer(struct kvm_vcpu *vcpu)
}

if (vmx->loaded_vmcs->hv_timer_armed)
- vmcs_clear_bits(PIN_BASED_VM_EXEC_CONTROL,
- PIN_BASED_VMX_PREEMPTION_TIMER);
+ pin_controls_clearbit(vmx, PIN_BASED_VMX_PREEMPTION_TIMER);
vmx->loaded_vmcs->hv_timer_armed = false;
}

diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 0a1b37d69f13..3c0a8b01f1f0 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -88,6 +88,7 @@ struct pt_desc {
struct vmx_controls_shadow {
u32 vm_entry;
u32 vm_exit;
+ u32 pin;
};

/*
@@ -423,6 +424,7 @@ static inline u8 vmx_get_rvi(void)
}
BUILD_CONTROLS_SHADOW(vm_entry, VM_ENTRY_CONTROLS)
BUILD_CONTROLS_SHADOW(vm_exit, VM_EXIT_CONTROLS)
+BUILD_CONTROLS_SHADOW(pin, PIN_BASED_VM_EXEC_CONTROL)

static inline void vmx_segment_cache_clear(struct vcpu_vmx *vmx)
{
--
1.8.3.1