Commit 6de12732 authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: VMX: Optimize vmx_get_rflags() 



If called several times within the same exit, return cached results.

Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent f6e78475

arch/x86/include/asm/kvm_host.h

+1 −0
Original line number Diff line number Diff line
@@ -118,6 +118,7 @@ enum kvm_reg { 
enum kvm_reg_ex {

	VCPU_EXREG_PDPTR = NR_VCPU_REGS,

	VCPU_EXREG_CR3,

	VCPU_EXREG_RFLAGS,

};



enum {

arch/x86/kvm/vmx.c

+14 −6
Original line number Diff line number Diff line
@@ -130,6 +130,7 @@ struct vcpu_vmx { 
	u8                    fail;

	u32                   exit_intr_info;

	u32                   idt_vectoring_info;

	ulong                 rflags;

	struct shared_msr_entry *guest_msrs;

	int                   nmsrs;

	int                   save_nmsrs;
@@ -970,17 +971,23 @@ static unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu) 
{

	unsigned long rflags, save_rflags;



	if (!test_bit(VCPU_EXREG_RFLAGS, (ulong *)&vcpu->arch.regs_avail)) {

		__set_bit(VCPU_EXREG_RFLAGS, (ulong *)&vcpu->arch.regs_avail);

		rflags = vmcs_readl(GUEST_RFLAGS);

		if (to_vmx(vcpu)->rmode.vm86_active) {

			rflags &= RMODE_GUEST_OWNED_EFLAGS_BITS;

			save_rflags = to_vmx(vcpu)->rmode.save_rflags;

			rflags |= save_rflags & ~RMODE_GUEST_OWNED_EFLAGS_BITS;

		}

	return rflags;

		to_vmx(vcpu)->rflags = rflags;

	}

	return to_vmx(vcpu)->rflags;

}



static void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)

{

	__set_bit(VCPU_EXREG_RFLAGS, (ulong *)&vcpu->arch.regs_avail);

	to_vmx(vcpu)->rflags = rflags;

	if (to_vmx(vcpu)->rmode.vm86_active) {

		to_vmx(vcpu)->rmode.save_rflags = rflags;

		rflags |= X86_EFLAGS_IOPL | X86_EFLAGS_VM;
@@ -4124,6 +4131,7 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu) 
	      );



	vcpu->arch.regs_avail = ~((1 << VCPU_REGS_RIP) | (1 << VCPU_REGS_RSP)

				  | (1 << VCPU_EXREG_RFLAGS)

				  | (1 << VCPU_EXREG_PDPTR)

				  | (1 << VCPU_EXREG_CR3));

	vcpu->arch.regs_dirty = 0;