Re: [PATCH v7 3/6] rust: irq: add support for non-threaded IRQs and handlers

[Daniel Almeida]

> On 21 Jul 2025, at 12:28, Danilo Krummrich <dakr@xxxxxxxxxx> wrote:
> 
> On Mon Jul 21, 2025 at 5:10 PM CEST, Daniel Almeida wrote:
>> Hi Alice, thanks for looking into this again :)
>> 
>> 
>> […]
>> 
>>>> diff --git a/rust/kernel/irq/request.rs b/rust/kernel/irq/request.rs
>>>> new file mode 100644
>>>> index 0000000000000000000000000000000000000000..2f4637d8bc4c9fda23cbc8307687035957b0042a
>>>> --- /dev/null
>>>> +++ b/rust/kernel/irq/request.rs
>>>> @@ -0,0 +1,267 @@
>>>> +// SPDX-License-Identifier: GPL-2.0
>>>> +// SPDX-FileCopyrightText: Copyright 2025 Collabora ltd.
>>>> +
>>>> +//! This module provides types like [`Registration`] which allow users to
>>>> +//! register handlers for a given IRQ line.
>>>> +
>>>> +use core::marker::PhantomPinned;
>>>> +
>>>> +use crate::alloc::Allocator;
>>>> +use crate::device::Bound;
>>>> +use crate::device::Device;
>>> 
>>> The usual style is to write this as:
>>> 
>>> use crate::device::{Bound, Device};
>> 
>> I dislike this syntax because I think it is a conflict magnet. Moreover, when
>> you get conflicts, they are harder to solve than they are when each import
>> is in its own line, at least IMHO.  
> 
> Intuitively, I would agree. However, I think practically it's not that bad.
> 
> While it's true that Rust has generally more conflict potential - especially in
> the current phase - my feeling hasn't been that includes produce significantly
> more conflicts then any other code so far.

Hmm, I faced lots of conflicts for the platform I/O stuff, for example. They
were all on the imports and it was a bit hard to fix it by hand. i.e.: it’s
much simpler to discard the modifications and then ask rust-analyzer to figure
out what should be grouped where on the new code. This is a bit undesirable.


> 
>> In any case, I don't think we have a guideline for imports at the moment?
> 
> No, but I think we should try to be as consistent as possible (at least within a
> a certain logical unit, e.g. subsystem, module, etc.). Not sure where exactly
> the IRQ stuff will end up yet. :)


Sure, I just think we should discuss this at the kernel crate level at a future
point then, at least IMHO. I think it's something that Andreas had already
commented on, by the way.

— Daniel