Re: [PATCH v1 3/9] powercap: intel_rapl: Use GENMASK() and BIT() macros

[David Laight]

On Thu, 29 Jan 2026 10:36:40 -0800
Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote:

> Replace hardcoded bitmasks and bit shift operations with standard
> GENMASK(), GENMASK_ULL(), BIT(), and BIT_ULL() macros for better
> readability and to follow kernel coding conventions.
> 
> No functional changes.

Assuming that changing values to 'unsigned long' doesn't have any
subtle side effects.

...
>  	value = (ra.value & ENERGY_UNIT_MASK) >> ENERGY_UNIT_OFFSET;
> -	rd->energy_unit = ENERGY_UNIT_SCALE * 1000000 / (1 << value);
> +	rd->energy_unit = ENERGY_UNIT_SCALE * 1000000 / BIT(value);

That should really be:
	rd->energy_unit = ENERGY_UNIT_SCALE * 1000000 >> value;

While using BIT() for bit patterns is resonable, wholesale substition
isn't really right - and that isn't a bit pattern.

	David