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

Gavin Shan
2022-01-11T07:53:03Z

Hi Eric,

On 11/9/21 11:26 PM, Eric Auger wrote:
> 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:
>

I agree. The code will be changed accordingly in next respin.

>> +#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?

I thought the inline function would come before the exposed ones. However,
I don't think it's necessary. I will drop the changes in next respin.

>> #endif
>>

Thanks,
Gavin