Re: [PATCH v4 04/18] KVM: arm64: selftests: Introduce ARM64_SYS_KVM_REG

[Raghavendra Rao Ananta]

On Wed, Sep 8, 2021 at 8:02 PM Oliver Upton <oupton@xxxxxxxxxx> wrote:
>
> Hi Raghu,
>
> On Thu, Sep 09, 2021 at 01:38:04AM +0000, Raghavendra Rao Ananta wrote:
> > With the inclusion of sysreg.h, that brings in system register
> > encodings, it would be redundant to re-define register encodings
> > again in processor.h to use it with ARM64_SYS_REG for the KVM
> > functions such as set_reg() or get_reg(). Hence, add helper macro,
> > ARM64_SYS_KVM_REG, that converts SYS_* definitions in sysreg.h
> > into ARM64_SYS_REG definitions.
> >
> > Signed-off-by: Raghavendra Rao Ananta <rananta@xxxxxxxxxx>
> > ---
> >  .../selftests/kvm/include/aarch64/processor.h      | 14 ++++++++++++++
> >  1 file changed, 14 insertions(+)
> >
> > diff --git a/tools/testing/selftests/kvm/include/aarch64/processor.h b/tools/testing/selftests/kvm/include/aarch64/processor.h
> > index bed4ffa70905..ac8b63f8aab7 100644
> > --- a/tools/testing/selftests/kvm/include/aarch64/processor.h
> > +++ b/tools/testing/selftests/kvm/include/aarch64/processor.h
> > @@ -26,6 +26,20 @@
> >
> >  #define ID_AA64DFR0_EL1         3, 0,  0, 5, 0
> >
> > +/*
> > + * ARM64_SYS_KVM_REG(sys_reg_id): Helper macro to convert
> > + * SYS_* register definitions in sysreg.h to use in KVM
> > + * calls such as get_reg() and set_reg().
> > + */
> > +#define ARM64_SYS_KVM_REG(sys_reg_id)                        \
>
> nit: KVM_ARM64_SYS_REG() perhaps? Dunno which is more readable.
>
> > +({                                                   \
> > +     ARM64_SYS_REG(sys_reg_Op0(sys_reg_id),          \
> > +                     sys_reg_Op1(sys_reg_id),        \
> > +                     sys_reg_CRn(sys_reg_id),        \
> > +                     sys_reg_CRm(sys_reg_id),        \
> > +                     sys_reg_Op2(sys_reg_id));       \
> > +})
> > +
>
Heh, I came up with the logic faster than picking a name for the
macro. I guess KVM_ARM64_SYS_REG may be more readable, just for the
fact that it begins with KVM_. I'll change it.

Regards,
Raghavendra
> Could you also switch all current users of ARM64_SYS_REG() in the KVM
> selftests directory in this commit? You can also drop the system
> register encodings defined in processor.h
>
I did that in a separate patch, but I can squash it here to avoid confusion.

Regards,
Raghavendra
> --
> Thanks,
> Oliver