Commit d89d04ab authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: move EXIT_FASTPATH_REENTER_GUEST to common code 



Now that KVM is using static calls, calling vmx_vcpu_run and
vmx_sync_pir_to_irr does not incur anymore the cost of a
retpoline.

Therefore there is no need anymore to handle EXIT_FASTPATH_REENTER_GUEST
in vendor code.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent fb18d053

arch/x86/kvm/vmx/vmx.c

+1 −18
Original line number Diff line number Diff line
@@ -6711,11 +6711,9 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu, 


static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)

{

	fastpath_t exit_fastpath;

	struct vcpu_vmx *vmx = to_vmx(vcpu);

	unsigned long cr3, cr4;



reenter_guest:

	/* Record the guest's net vcpu time for enforced NMI injections. */

	if (unlikely(!enable_vnmi &&

		     vmx->loaded_vmcs->soft_vnmi_blocked))
@@ -6865,22 +6863,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) 
	if (is_guest_mode(vcpu))

		return EXIT_FASTPATH_NONE;



	exit_fastpath = vmx_exit_handlers_fastpath(vcpu);

	if (exit_fastpath == EXIT_FASTPATH_REENTER_GUEST) {

		if (!kvm_vcpu_exit_request(vcpu)) {

			/*

			 * FIXME: this goto should be a loop in vcpu_enter_guest,

			 * but it would incur the cost of a retpoline for now.

			 * Revisit once static calls are available.

			 */

			if (vcpu->arch.apicv_active)

				vmx_sync_pir_to_irr(vcpu);

			goto reenter_guest;

		}

		exit_fastpath = EXIT_FASTPATH_EXIT_HANDLED;

	}



	return exit_fastpath;

	return vmx_exit_handlers_fastpath(vcpu);

}



static void vmx_free_vcpu(struct kvm_vcpu *vcpu)

arch/x86/kvm/x86.c

+14 −3
Original line number Diff line number Diff line
@@ -1796,12 +1796,11 @@ int kvm_emulate_wrmsr(struct kvm_vcpu *vcpu) 
}

EXPORT_SYMBOL_GPL(kvm_emulate_wrmsr);



bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu)

static inline bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu)

{

	return vcpu->mode == EXITING_GUEST_MODE || kvm_request_pending(vcpu) ||

		xfer_to_guest_mode_work_pending();

}

EXPORT_SYMBOL_GPL(kvm_vcpu_exit_request);



/*

 * The fast path for frequent and performance sensitive wrmsr emulation,
@@ -9044,7 +9043,19 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) 
		vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_RELOAD;

	}



	for (;;) {

		exit_fastpath = static_call(kvm_x86_run)(vcpu);

		if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))

			break;



                if (unlikely(kvm_vcpu_exit_request(vcpu))) {

			exit_fastpath = EXIT_FASTPATH_EXIT_HANDLED;

			break;

		}



		if (vcpu->arch.apicv_active)

			static_call(kvm_x86_sync_pir_to_irr)(vcpu);

        }



	/*

	 * Do this here before restoring debug registers on the host.  And

arch/x86/kvm/x86.h

+0 −1
Original line number Diff line number Diff line
@@ -395,7 +395,6 @@ void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu); 
void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu);

int kvm_spec_ctrl_test_value(u64 value);

bool kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);

bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu);

int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r,

			      struct x86_exception *e);

int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva);