2020-04-23 02:29:19

by Sean Christopherson

Subject: [PATCH 13/13] KVM: VMX: Use vmx_get_rflags() to query RFLAGS in vmx_interrupt_blocked()

Use vmx_get_rflags() instead of manually reading vmcs.GUEST_RFLAGS when
querying RFLAGS.IF so that multiple checks against interrupt blocking in
a single run loop only require a single VMREAD.

Signed-off-by: Sean Christopherson <[email protected]>
---
arch/x86/kvm/vmx/vmx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 68b3748b5383..9c4dd481b588 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4537,7 +4537,7 @@ bool vmx_interrupt_blocked(struct kvm_vcpu *vcpu)
if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu))
return false;

- return !(vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) ||
+ return !(vmx_get_rflags(vcpu) & X86_EFLAGS_IF) ||
(vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
(GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS));
}
--
2.26.0

2020-04-28 22:17:45

by Jim Mattson

Subject: Re: [PATCH 13/13] KVM: VMX: Use vmx_get_rflags() to query RFLAGS in vmx_interrupt_blocked()

On Wed, Apr 22, 2020 at 7:26 PM Sean Christopherson
<[email protected]> wrote:
>
> Use vmx_get_rflags() instead of manually reading vmcs.GUEST_RFLAGS when
> querying RFLAGS.IF so that multiple checks against interrupt blocking in
> a single run loop only require a single VMREAD.
>
> Signed-off-by: Sean Christopherson <[email protected]>
Reviewed-by: Jim Mattson <[email protected]>