[PATCH v4 2/3] KVM: PPC: epapr: Add idle hcall support for host

[Liu Yu-B13201]

> -----Original Message-----
> From: Alexander Graf [mailto:agraf at suse.de]
> Sent: Thursday, February 16, 2012 6:20 PM
> To: Liu Yu-B13201
> Cc: <kvm-ppc at vger.kernel.org>; <kvm at vger.kernel.org>; <linuxppc-
> dev at ozlabs.org>; Wood Scott-B07421; Liu Yu-B13201
> Subject: Re: [PATCH v4 2/3] KVM: PPC: epapr: Add idle hcall support for
> host
> 
> 
> 
> On 16.02.2012, at 10:26, Liu Yu <yu.liu at freescale.com> wrote:
> 
> > And add a new flag definition in kvm_ppc_pvinfo to indicate whether
> > host support EV_IDLE hcall.
> >
> > Signed-off-by: Liu Yu <yu.liu at freescale.com>
> > ---
> > v4:
> > no change
> >
> > arch/powerpc/include/asm/kvm_para.h |   14 ++++++++++++--
> > arch/powerpc/kvm/powerpc.c          |    8 ++++++++
> > include/linux/kvm.h                 |    2 ++
> > 3 files changed, 22 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/powerpc/include/asm/kvm_para.h
> > b/arch/powerpc/include/asm/kvm_para.h
> > index 7b754e7..81a34c9 100644
> > --- a/arch/powerpc/include/asm/kvm_para.h
> > +++ b/arch/powerpc/include/asm/kvm_para.h
> > @@ -75,9 +75,19 @@ struct kvm_vcpu_arch_shared { };
> >
> > #define KVM_SC_MAGIC_R0        0x4b564d21 /* "KVM!" */
> > -#define HC_VENDOR_KVM        (42 << 16)
> > +
> > +#include <asm/epapr_hcalls.h>
> > +
> > +/* ePAPR Hypercall Vendor ID */
> > +#define HC_VENDOR_EPAPR        (EV_EPAPR_VENDOR_ID << 16)
> > +#define HC_VENDOR_KVM        (EV_KVM_VENDOR_ID << 16)
> > +
> > +/* ePAPR Hypercall Token */
> > +#define HC_EV_IDLE        EV_IDLE
> > +
> > +/* ePAPR Hypercall Return Codes */
> > #define HC_EV_SUCCESS        0
> > -#define HC_EV_UNIMPLEMENTED    12
> > +#define HC_EV_UNIMPLEMENTED    EV_UNIMPLEMENTED
> >
> > #define KVM_FEATURE_MAGIC_PAGE    1
> >
> > diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
> > index 0e21d15..03ebd5d 100644
> > --- a/arch/powerpc/kvm/powerpc.c
> > +++ b/arch/powerpc/kvm/powerpc.c
> > @@ -81,6 +81,10 @@ int kvmppc_kvm_pv(struct kvm_vcpu *vcpu)
> >
> >        /* Second return value is in r4 */
> >        break;
> > +    case HC_VENDOR_EPAPR | HC_EV_IDLE:
> > +        r = HC_EV_SUCCESS;
> > +        kvm_vcpu_block(vcpu);
> > +        break;
> >    default:
> >        r = HC_EV_UNIMPLEMENTED;
> >        break;
> > @@ -746,6 +750,10 @@ static int kvm_vm_ioctl_get_pvinfo(struct
> kvm_ppc_pvinfo *pvinfo)
> >    pvinfo->hcall[2] = inst_sc;
> >    pvinfo->hcall[3] = inst_nop;
> >
> > +#ifdef CONFIG_BOOKE
> > +    pvinfo->flags |= KVM_PPC_PVINFO_FLAGS_EV_IDLE; #endif
> > +
> >    return 0;
> > }> 
>
> Why limit it to booke? The less ifdefs our code has, the better :)

The code here tells userspace that kvm support ev_idle.
But I'm not sure if the ev_idle code works for other platforms.

So I think we should keep the ifdef until other platform test the code :)

Thanks,
Yu