Re: [PATCH] ACPI: rename acpi_arm_init to acpi_arch_init

[Hanjun Guo <guohanjun@huawei.com>]

On 2024/7/27 2:23, Miao Wang wrote:
> 
>> 2024年7月27日 01:55，Sunil V L <sunilvl@ventanamicro.com> 写道：
>>
>> On Sat, Jul 27, 2024 at 12:39:03AM +0800, Miao Wang wrote:
>>> Hi,
>>>
>>> Thanks for your quick reply.
>>>
>>>> 2024年7月27日 00:05，Sudeep Holla <sudeep.holla@arm.com> 写道：
>>>>
>>>> On Fri, Jul 26, 2024 at 11:03:01PM +0800, Miao Wang via B4 Relay wrote:
[...]
>>>>>
>>>>> -#ifdef CONFIG_ARM64
>>>>> -void acpi_arm_init(void);
>>>>> +#ifdef ACPI_HAVE_ARCH_INIT
>>>>> +void acpi_arch_init(void);
>>>>
>>>> This is bit inconsistent. The Makefile is still conditional on
>>>> CONFIG_ARM64 while here you move to ACPI_HAVE_ARCH_INIT.
>>>> So while not just undefine and redefine acpi_arch_init to acpi_arm_init.
>>>> Something like this must work ?
>>>>
>>>> #define acpi_arch_init() do { }while(0)
>>>>
>>>> #ifdef CONFIG_ARM64
>>>> #undef acpi_arch_init
>>>> #define acpi_arch_init() acpi_arm_init()
>>>> #endif
>>>
>>> It will work. However I can see the pattern in other parts, where
>>> the definition of a macro named HAVE_xxx is checked, and define an
>>> inline static function with empty body if such macro is not defined
>>> or define a function prototype with the same name otherwise, like
>>> acpi_arch_set_root_pointer. I'm just trying to follow this pattern.
>>>
>> I was thinking to make it weak function similar to cpc_read_ffh().
>> Wouldn't it be better than ifdefery?
> 
> I believe there would be performance loss for those arches with a stub
> function definition if a weak function is used (correct me if wrong).
> So the approach with a static inline stub is more common in the kernel
> code.

ACPI init is not in the hot code path, no worries for the performance
loss.

Weak function is my preference too :)

Thanks
Hanjun