Commit dcf068da authored by Wanpeng Li's avatar Wanpeng Li Committed by Paolo Bonzini
Browse files

KVM: VMX: Introduce generic fastpath handler 



Introduce generic fastpath handler to handle MSR fastpath, VMX-preemption
timer fastpath etc; move it after vmx_complete_interrupts() in order to
catch events delivered to the guest, and abort the fast path in later
patches.  While at it, move the kvm_exit tracepoint so that it is printed
for fastpath vmexits as well.

There is no observed performance effect for the IPI fastpath after this patch.

Tested-by: default avatarHaiwei Li <lihaiwei@tencent.com>
Cc: Haiwei Li <lihaiwei@tencent.com>
Signed-off-by: default avatarWanpeng Li <wanpengli@tencent.com>
Suggested-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <1588055009-12677-2-git-send-email-wanpengli@tencent.com>
Reviewed-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 9e826feb

arch/x86/kvm/vmx/vmx.c

+16 −7
Original line number Diff line number Diff line
@@ -5933,8 +5933,6 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, 
	u32 exit_reason = vmx->exit_reason;

	u32 vectoring_info = vmx->idt_vectoring_info;



	trace_kvm_exit(exit_reason, vcpu, KVM_ISA_VMX);



	/*

	 * Flush logged GPAs PML buffer, this will make dirty_bitmap more

	 * updated. Another good is, in kvm_vm_ioctl_get_dirty_log, before
@@ -6630,6 +6628,16 @@ void vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp) 
	}

}



static enum exit_fastpath_completion vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu)

{

	switch (to_vmx(vcpu)->exit_reason) {

	case EXIT_REASON_MSR_WRITE:

		return handle_fastpath_set_msr_irqoff(vcpu);

	default:

		return EXIT_FASTPATH_NONE;

	}

}



bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs, bool launched);



static enum exit_fastpath_completion vmx_vcpu_run(struct kvm_vcpu *vcpu)
@@ -6784,20 +6792,21 @@ static enum exit_fastpath_completion vmx_vcpu_run(struct kvm_vcpu *vcpu) 
	if (unlikely((u16)vmx->exit_reason == EXIT_REASON_MCE_DURING_VMENTRY))

		kvm_machine_check();



	trace_kvm_exit(vmx->exit_reason, vcpu, KVM_ISA_VMX);



	if (unlikely(vmx->exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY))

		return EXIT_FASTPATH_NONE;



	if (!is_guest_mode(vcpu) && vmx->exit_reason == EXIT_REASON_MSR_WRITE)

		exit_fastpath = handle_fastpath_set_msr_irqoff(vcpu);

	else

		exit_fastpath = EXIT_FASTPATH_NONE;



	vmx->loaded_vmcs->launched = 1;

	vmx->idt_vectoring_info = vmcs_read32(IDT_VECTORING_INFO_FIELD);



	vmx_recover_nmi_blocking(vmx);

	vmx_complete_interrupts(vmx);



	if (is_guest_mode(vcpu))

		return EXIT_FASTPATH_NONE;



	exit_fastpath = vmx_exit_handlers_fastpath(vcpu);

	return exit_fastpath;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE