Re: [PATCH v4 01/21] KVM: arm64: Introduce template for inline functions

Eric Auger
2021-11-09T15:26:08Z

Hi Gavin,

On 8/15/21 2:13 AM, Gavin Shan wrote:
> The inline functions used to get the SMCCC parameters have same
> layout. It means these functions can be presented by a template,
> to make the code simplified. Besides, this adds more similar inline
> functions like smccc_get_arg{4,5,6,7,8}() to visit more SMCCC arguments,
> which are needed by SDEI virtualization support.
>
> Signed-off-by: Gavin Shan <gshan@redhat.com>
> ---
> include/kvm/arm_hypercalls.h | 34 +++++++++++++++-------------------
> 1 file changed, 15 insertions(+), 19 deletions(-)
>
> diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h
> index 0e2509d27910..ebecb6c68254 100644
> --- a/include/kvm/arm_hypercalls.h
> +++ b/include/kvm/arm_hypercalls.h
> @@ -6,27 +6,21 @@
>
> #include <asm/kvm_emulate.h>
>
> -int kvm_hvc_call_handler(struct kvm_vcpu *vcpu);
> -
> -static inline u32 smccc_get_function(struct kvm_vcpu *vcpu)
> -{
> - return vcpu_get_reg(vcpu, 0);
> +#define SMCCC_DECLARE_GET_FUNC(type, name, reg) \
> +static inline type smccc_get_##name(struct kvm_vcpu *vcpu) \
> +{ \
> + return vcpu_get_reg(vcpu, reg); \
> }
>
> -static inline unsigned long smccc_get_arg1(struct kvm_vcpu *vcpu)
> -{
> - return vcpu_get_reg(vcpu, 1);
> -}
> -
> -static inline unsigned long smccc_get_arg2(struct kvm_vcpu *vcpu)
> -{
> - return vcpu_get_reg(vcpu, 2);
> -}
> -
> -static inline unsigned long smccc_get_arg3(struct kvm_vcpu *vcpu)
> -{
> - return vcpu_get_reg(vcpu, 3);
> -}
> +SMCCC_DECLARE_GET_FUNC(u32, function, 0)
> +SMCCC_DECLARE_GET_FUNC(unsigned long, arg1, 1)
> +SMCCC_DECLARE_GET_FUNC(unsigned long, arg2, 2)
> +SMCCC_DECLARE_GET_FUNC(unsigned long, arg3, 3)
> +SMCCC_DECLARE_GET_FUNC(unsigned long, arg4, 4)
> +SMCCC_DECLARE_GET_FUNC(unsigned long, arg5, 5)
> +SMCCC_DECLARE_GET_FUNC(unsigned long, arg6, 6)
> +SMCCC_DECLARE_GET_FUNC(unsigned long, arg7, 7)
> +SMCCC_DECLARE_GET_FUNC(unsigned long, arg8, 8)
I think I would keep smccc_get_function() and add macros to get the
64-bit args. SMCCC_DECLARE_GET_FUNC is an odd macro name for a function
fetching an arg. I would suggest:

> +#define SMCCC_DECLARE_GET_ARG(reg) \
> +static inline unsigned long smccc_get_arg##reg(struct kvm_vcpu *vcpu) \
> +{ \
> + return vcpu_get_reg(vcpu, reg); \
> }
>
> static inline void smccc_set_retval(struct kvm_vcpu *vcpu,
> unsigned long a0,
> @@ -40,4 +34,6 @@ static inline void smccc_set_retval(struct kvm_vcpu *vcpu,
> vcpu_set_reg(vcpu, 3, a3);
> }
>
> +int kvm_hvc_call_handler(struct kvm_vcpu *vcpu);
> +
spurious change?
> #endif
>
Thanks

Eric