Re: [PATCH v2 2/3] KVM: VMX: Rename {vmx,nested_vmx}_vcpu_setup() and minor cleanup

[Xiaoyao Li]

On 10/19/2019 1:09 AM, Sean Christopherson wrote:

On Fri, Oct 18, 2019 at 05:37:22PM +0800, Xiaoyao Li wrote:

Rename {vmx,nested_vmx}_vcpu_setup() to {vmx,nested_vmx}_vmcs_setup,
to match what they really do.

Aslo remove the vmcs unrelated codes to vmx_vcpu_create().

Do this in a separate patch, just in case there is a dependencies we're
missing.

The initialization of vmx->hv_deadline_tsc can be removed here, because
it will be called in vmx_vcpu_reset() as the flow:

kvm_arch_vcpu_setup()
   -> kvm_vcpu_reset()
        -> vmx_vcpu_reset()

Definitely needs to be in a separate patch.

OK, I'll split it into 3 patches.

Signed-off-by: Xiaoyao Li <xiaoyao...@intel.com>
---
Changes in v2:
   - move out the vmcs unrelated codes
---
  arch/x86/kvm/vmx/nested.c |  2 +-
  arch/x86/kvm/vmx/nested.h |  2 +-
  arch/x86/kvm/vmx/vmx.c    | 45 +++++++++++++++++----------------------
  3 files changed, 22 insertions(+), 27 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 5e231da00310..7935422d311f 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -5768,7 +5768,7 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu,
        return ret;
  }

-void nested_vmx_vcpu_setup(void)

+void nested_vmx_vmcs_setup(void)

"vmcs_setup" sounds like we're allocating and loading a VMCS.  Maybe
{nested_,}vmx_set_initial_vmcs_state() a la vmx_set_constant_host_state()?

  {
        if (enable_shadow_vmcs) {
                vmcs_write64(VMREAD_BITMAP, __pa(vmx_vmread_bitmap));
diff --git a/arch/x86/kvm/vmx/nested.h b/arch/x86/kvm/vmx/nested.h
index 187d39bf0bf1..2be1ba7482c9 100644
--- a/arch/x86/kvm/vmx/nested.h
+++ b/arch/x86/kvm/vmx/nested.h
@@ -11,7 +11,7 @@ void nested_vmx_setup_ctls_msrs(struct nested_vmx_msrs *msrs, 
u32 ept_caps,
                                bool apicv);
  void nested_vmx_hardware_unsetup(void);
  __init int nested_vmx_hardware_setup(int (*exit_handlers[])(struct kvm_vcpu 
*));
-void nested_vmx_vcpu_setup(void);
+void nested_vmx_vmcs_setup(void);
  void nested_vmx_free_vcpu(struct kvm_vcpu *vcpu);
  int nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu, bool from_vmentry);
  bool nested_vmx_exit_reflected(struct kvm_vcpu *vcpu, u32 exit_reason);
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index ef567df344bf..b083316a598d 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4161,15 +4161,10 @@ static void ept_set_mmio_spte_mask(void)

#define VMX_XSS_EXIT_BITMAP 0 -/*

- * Sets up the vmcs for emulated real mode.
- */
-static void vmx_vcpu_setup(struct vcpu_vmx *vmx)
+static void vmx_vmcs_setup(struct vcpu_vmx *vmx)
  {
-       int i;
-
        if (nested)
-               nested_vmx_vcpu_setup();
+               nested_vmx_vmcs_setup();

if (cpu_has_vmx_msr_bitmap())

                vmcs_write64(MSR_BITMAP, __pa(vmx->vmcs01.msr_bitmap));
@@ -4178,7 +4173,6 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx)

/* Control */

        pin_controls_set(vmx, vmx_pin_based_exec_ctrl(vmx));
-       vmx->hv_deadline_tsc = -1;

exec_controls_set(vmx, vmx_exec_control(vmx)); @@ -4227,21 +4221,6 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx)

        if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT)
                vmcs_write64(GUEST_IA32_PAT, vmx->vcpu.arch.pat);

- for (i = 0; i < ARRAY_SIZE(vmx_msr_index); ++i) {

-               u32 index = vmx_msr_index[i];
-               u32 data_low, data_high;
-               int j = vmx->nmsrs;
-
-               if (rdmsr_safe(index, &data_low, &data_high) < 0)
-                       continue;
-               if (wrmsr_safe(index, data_low, data_high) < 0)
-                       continue;
-               vmx->guest_msrs[j].index = i;
-               vmx->guest_msrs[j].data = 0;
-               vmx->guest_msrs[j].mask = -1ull;
-               ++vmx->nmsrs;
-       }
-
        vm_exit_controls_set(vmx, vmx_vmexit_ctrl());

/* 22.2.1, 20.8.1 */

@@ -6710,7 +6689,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, 
unsigned int id)
        int err;
        struct vcpu_vmx *vmx;
        unsigned long *msr_bitmap;
-       int cpu;
+       int i, cpu;

BUILD_BUG_ON_MSG(offsetof(struct vcpu_vmx, vcpu) != 0,

                "struct kvm_vcpu must be at offset 0 for arch usercopy region");
@@ -6786,9 +6765,25 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, 
unsigned int id)
        cpu = get_cpu();
        vmx_vcpu_load(&vmx->vcpu, cpu);
        vmx->vcpu.cpu = cpu;
-       vmx_vcpu_setup(vmx);
+       vmx_vmcs_setup(vmx);
        vmx_vcpu_put(&vmx->vcpu);
        put_cpu();
+
+       for (i = 0; i < ARRAY_SIZE(vmx_msr_index); ++i) {
+               u32 index = vmx_msr_index[i];
+               u32 data_low, data_high;
+               int j = vmx->nmsrs;
+
+               if (rdmsr_safe(index, &data_low, &data_high) < 0)
+                       continue;
+               if (wrmsr_safe(index, data_low, data_high) < 0)
+                       continue;
+               vmx->guest_msrs[j].index = i;
+               vmx->guest_msrs[j].data = 0;
+               vmx->guest_msrs[j].mask = -1ull;
+               ++vmx->nmsrs;
+       }

I'd put this immediately after guest_msrs is allocated.  Yeah, we'll waste
a few cycles if allocating vmcs01 fails, but that should be a very rare
event.

OK.

+
        if (cpu_need_virtualize_apic_accesses(&vmx->vcpu)) {
                err = alloc_apic_access_page(kvm);
                if (err)
--
2.19.1