Re: [PATCH v9 3/8] rust: time: Introduce Delta type

[Gary Guo]

On Sat, 25 Jan 2025 19:18:48 +0900
FUJITA Tomonori <fujita.tomonori@xxxxxxxxx> wrote:

> Introduce a type representing a span of time. Define our own type
> because `core::time::Duration` is large and could panic during
> creation.
> 
> time::Ktime could be also used for time duration but timestamp and
> timedelta are different so better to use a new type.
> 
> i64 is used instead of u64 to represent a span of time; some C drivers
> uses negative Deltas and i64 is more compatible with Ktime using i64
> too (e.g., ktime_[us|ms]_delta() APIs return i64 so we create Delta
> object without type conversion.
> 
> i64 is used instead of bindings::ktime_t because when the ktime_t
> type is used as timestamp, it represents values from 0 to
> KTIME_MAX, which is different from Delta.
> 
> as_millis() method isn't used in this patchset. It's planned to be
> used in Binder driver.
> 
> Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
> Reviewed-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxx>

Reviewed-by: Gary Guo <gary@xxxxxxxxxxx>

> ---
>  rust/kernel/time.rs | 88 +++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 88 insertions(+)