linux-kernel - Re: [PATCH v8 4/7] rust: time: Add wrapper for fsleep function

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Message-Id: <20250122.202713.205090167743426793.fujita.tomonori@gmail.com>
Date: Wed, 22 Jan 2025 20:27:13 +0900 (JST)
From: FUJITA Tomonori <fujita.tomonori@...il.com>
To: aliceryhl@...gle.com
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Subject: Re: [PATCH v8 4/7] rust: time: Add wrapper for fsleep function

On Wed, 22 Jan 2025 11:47:38 +0100
Alice Ryhl <aliceryhl@...gle.com> wrote:

>> >> Ah, it might work. The following doesn't work. Seems that we need to
>> >> add another const like MAX_DELTA_NANOS or something. No strong
>> >> preference but I feel the current is simpler.
>> >>
>> >> let delta = match delta.as_nanos() {
>> >>     0..=MAX_DELTA.as_nanos() as i32 => delta,
>> >>     _ => MAX_DELTA,
>> >> };
>> >
>> > Could you do Delta::min(delta, MAX_DELTA).as_nanos() ?
>>
>> We need Delta type here so you meant:
>>
>> let delta = std::cmp::min(delta, MAX_DELTA);
> 
> If `Delta` implements the `Ord` trait, then you can write `Delta::min`
> to take the minimum of two deltas. It's equivalent to `std::cmp::min`,
> of course.

Ah, nice.

>> We also need to convert a negative delta to MAX_DELTA so we could do:
>>
>> let delta = if delta.is_negative() {
>>     MAX_DELTA
>> } else {
>>     min(delta, MAX_DELTA)
>> };
>>
>> looks a bit readable than the original code?
> 
> At that point we might as well write
> 
>     if delta.is_negative() || delta > MAX_DELTA
> 
> and skip the call to `min`.

Yeah, it's what the original code does. I'll leave this code alone.