Re: [PATCH] rust: time: add Ktime

[Alice Ryhl]

On Wed, Mar 20, 2024 at 4:30 PM Boqun Feng <boqun.feng@xxxxxxxxx> wrote:
>
> Hi,
>
> On Wed, Mar 20, 2024 at 10:08:45AM +0000, Alice Ryhl wrote:
> > Introduce a wrapper around `ktime_t` with a few different useful
> > methods.
> >
> > Rust Binder will use these bindings to compute how many milliseconds a
> > transaction has been active for when dumping the current state of the
> > Binder driver. This replicates the logic in C Binder [1].
> >
>
> I wonder whether Lina's previous patch also works for your case?
>
>         https://lore.kernel.org/rust-for-linux/20230714-rust-time-v2-1-f5aed84218c4@xxxxxxxxxxxxx/
>
> You don't need to implement all the `Clock`s since you only need
> MONOTONIC time. But maybe `Duration::as_nanos` and `Duration::as_millis`
> return `u128` is problematic?

It would work for me too, but adds more than what I need. As for
`u128`, I don't really know what the status on that is. I need to be
able to print it as a base-10 integer.

Adding an API with separate types that distinguish between Instant and
Duration and different clock sources so that you don't mix them up is
reasonable, but a bit overkill for my needs. I am spending enough API
design cycles on my uaccess, file, and linked list patchsets. Someone
else can submit patches to add a more well-typed time API in the
future.

Alice