On Wed, 2021-10-27 at 17:10 +0300, Maxim Levitsky wrote:
> On Fri, 2021-10-08 at 19:12 -0700, Sean Christopherson wrote:
> > Rename a variety of HLT-related helpers to free up the function name
> > "kvm_vcpu_halt" for future use in generic KVM code, e.g. to differentiate
> > between "block" and "halt".
> >
> > No functional change intended.
> >
> > Reviewed-by: David Matlack <dmatlack@xxxxxxxxxx>
> > Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> > ---
> > arch/x86/include/asm/kvm_host.h | 2 +-
> > arch/x86/kvm/vmx/nested.c | 2 +-
> > arch/x86/kvm/vmx/vmx.c | 4 ++--
> > arch/x86/kvm/x86.c | 13 +++++++------
> > 4 files changed, 11 insertions(+), 10 deletions(-)
> >
> > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> > index 7aafc27ce7a9..328103a520d3 100644
> > --- a/arch/x86/include/asm/kvm_host.h
> > +++ b/arch/x86/include/asm/kvm_host.h
> > @@ -1689,7 +1689,7 @@ int kvm_emulate_monitor(struct kvm_vcpu *vcpu);
> > int kvm_fast_pio(struct kvm_vcpu *vcpu, int size, unsigned short port, int in);
> > int kvm_emulate_cpuid(struct kvm_vcpu *vcpu);
> > int kvm_emulate_halt(struct kvm_vcpu *vcpu);
> > -int kvm_vcpu_halt(struct kvm_vcpu *vcpu);
> > +int kvm_emulate_halt_noskip(struct kvm_vcpu *vcpu);
> > int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu);
> > int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu);
> >
> > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
> > index af1bbb73430a..d0237a441feb 100644
> > --- a/arch/x86/kvm/vmx/nested.c
> > +++ b/arch/x86/kvm/vmx/nested.c
> > @@ -3619,7 +3619,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
> > !(nested_cpu_has(vmcs12, CPU_BASED_INTR_WINDOW_EXITING) &&
> > (vmcs12->guest_rflags & X86_EFLAGS_IF))) {
> > vmx->nested.nested_run_pending = 0;
> > - return kvm_vcpu_halt(vcpu);
> > + return kvm_emulate_halt_noskip(vcpu);
> > }
> > break;
> > case GUEST_ACTIVITY_WAIT_SIPI:
> > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> > index 1c8b2b6e7ed9..5517893f12fc 100644
> > --- a/arch/x86/kvm/vmx/vmx.c
> > +++ b/arch/x86/kvm/vmx/vmx.c
> > @@ -4741,7 +4741,7 @@ static int handle_rmode_exception(struct kvm_vcpu *vcpu,
> > if (kvm_emulate_instruction(vcpu, 0)) {
> > if (vcpu->arch.halt_request) {
> > vcpu->arch.halt_request = 0;
> > - return kvm_vcpu_halt(vcpu);
> > + return kvm_emulate_halt_noskip(vcpu);
>
> Could you elaborate on why you choose _noskip suffix?
>
> As far as I see, kvm_vcpu_halt just calls __kvm_vcpu_halt with new VCPU run state/exit reason,
> which is used only when local apic is not in the kernel (which is these days not that
> supported configuration).
>
> Other user of __kvm_vcpu_halt is something SEV related.
>
> Best regards,
> Maxim Levitsky
>
>
> > }
> > return 1;
> > }
> > @@ -5415,7 +5415,7 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
> >
> > if (vcpu->arch.halt_request) {
> > vcpu->arch.halt_request = 0;
> > - return kvm_vcpu_halt(vcpu);
> > + return kvm_emulate_halt_noskip(vcpu);
> > }
> >
> > /*
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index 4a52a08707de..9c23ae1d483d 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -8649,7 +8649,7 @@ void kvm_arch_exit(void)
> > #endif
> > }
> >
> > -static int __kvm_vcpu_halt(struct kvm_vcpu *vcpu, int state, int reason)
> > +static int __kvm_emulate_halt(struct kvm_vcpu *vcpu, int state, int reason)
> > {
> > ++vcpu->stat.halt_exits;
> > if (lapic_in_kernel(vcpu)) {
> > @@ -8661,11 +8661,11 @@ static int __kvm_vcpu_halt(struct kvm_vcpu *vcpu, int state, int reason)
> > }
> > }
> >
> > -int kvm_vcpu_halt(struct kvm_vcpu *vcpu)
> > +int kvm_emulate_halt_noskip(struct kvm_vcpu *vcpu)
> > {
> > - return __kvm_vcpu_halt(vcpu, KVM_MP_STATE_HALTED, KVM_EXIT_HLT);
> > + return __kvm_emulate_halt(vcpu, KVM_MP_STATE_HALTED, KVM_EXIT_HLT);
> > }
> > -EXPORT_SYMBOL_GPL(kvm_vcpu_halt);
> > +EXPORT_SYMBOL_GPL(kvm_emulate_halt_noskip);
> >
> > int kvm_emulate_halt(struct kvm_vcpu *vcpu)
> > {
> > @@ -8674,7 +8674,7 @@ int kvm_emulate_halt(struct kvm_vcpu *vcpu)
> > * TODO: we might be squashing a GUESTDBG_SINGLESTEP-triggered
> > * KVM_EXIT_DEBUG here.
> > */
> > - return kvm_vcpu_halt(vcpu) && ret;
> > + return kvm_emulate_halt_noskip(vcpu) && ret;
> > }
> > EXPORT_SYMBOL_GPL(kvm_emulate_halt);
> >
> > @@ -8682,7 +8682,8 @@ int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu)
> > {
> > int ret = kvm_skip_emulated_instruction(vcpu);
> >
> > - return __kvm_vcpu_halt(vcpu, KVM_MP_STATE_AP_RESET_HOLD, KVM_EXIT_AP_RESET_HOLD) && ret;
> > + return __kvm_emulate_halt(vcpu, KVM_MP_STATE_AP_RESET_HOLD,
> > + KVM_EXIT_AP_RESET_HOLD) && ret;
> > }
> > EXPORT_SYMBOL_GPL(kvm_emulate_ap_reset_hold);
> >
Also while at it, why not to use say '__kvm_emulate_hlt' ('hlt' instead of 'halt') to
put emphasis on the fact that we are emulating a cpu instruction?
Best regards,
Maxim Levitsky
