RE: [PATCH] staging: pi433: Use div64_u64 instead of do_div

[David Laight]

From: Kang Minchul
> Sent: 19 October 2022 10:40
> 
> This commit removes warning generated by cocci as follows:
> 
> do_div() does a 64-by-32 division, please consider using div64_u64 instead.
> 
> Using div64_u64 instead of do_div can avoid potential truncation.

Cocci is lying to you.

do_div() exists because a 64 by 32 bit divide is significantly
faster than a 64 by 64 divide.
This is particularly true on 32bit cpu, but is also true on
Intel x86_64 bit cpu.

So unless the result might actually be larger than 32 bits
(which requires code analysis) then do_div() is correct.

	David

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