Re: [PATCHv3 04/10] linux/kernel: introduce lower_48_bits macro

Chaitanya Kulkarni
2022-02-22T17:15:01Z

On 2/22/22 08:50, Christoph Hellwig wrote:
> On Tue, Feb 22, 2022 at 08:45:53AM -0800, Joe Perches wrote:
>> On Tue, 2022-02-22 at 08:31 -0800, Keith Busch wrote:
>>> Recent data integrity field enhancements allow 48-bit reference tags.
>>> Introduce a helper macro since this will be a repeated operation.
>> []
>>> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
>> []
>>> @@ -63,6 +63,12 @@
>>> } \
>>> )
>>>
>>> +/**
>>> + * lower_48_bits - return bits 0-47 of a number
>>> + * @n: the number we're accessing
>>> + */
>>> +#define lower_48_bits(n) ((u64)((n) & 0xffffffffffffull))
>>
>> why not make this a static inline function?
>
> Agreed.
>

All the bit maskd macros in the same file needs to be converted into
static inline to have the right data type, however that needs to be
done once this series is in, since clearly objective of this series
is different than cleanup of include/linux/kernel.h bit macros.

-ck