Re: [PATCH net-next v3 3/8] rust: time: Change output of Ktime's sub operation to Delta

[FUJITA Tomonori]

On Wed, 16 Oct 2024 13:03:48 -0700
Boqun Feng <boqun.feng@xxxxxxxxx> wrote:

>>  impl core::ops::Sub for Ktime {
>> -    type Output = Ktime;
>> +    type Output = Delta;
>>  
>>      #[inline]
>> -    fn sub(self, other: Ktime) -> Ktime {
>> -        Self {
>> -            inner: self.inner - other.inner,
>> +    fn sub(self, other: Ktime) -> Delta {
>> +        Delta {
>> +            nanos: self.inner - other.inner,
> 
> My understanding is that ktime_t, when used as a timestamp, can only
> have a value in range [0, i64::MAX], so this substraction here never
> overflows, maybe we want add a comment here?

Sure, I'll add.