Re: [PATCH v3 5/7] rust: percpu: Support non-zeroable types for DynamicPerCpu

[Yury Norov <yury.norov@gmail.com>]

> > 
> >         for_each_possible_cpu(cpu) {
> >                 let remote_ptr = unsafe { ptr.get_remote_ptr(cpu) };
> >                 unsafe { (*remote_ptr).write(val.clone()); }
> >                 let arc = Arc::new(alloc, flags).ok()?;
> >                 Some(Self { alloc: arc })
> >         }
> > 
> > Is it possible to do the above in rust?
> 
> Ah, I see.
> 
> The syntax would be slightly different, probably something like
> 
>         use cpu::for_each_possible_cpu;
> 
>         for_each_possible_cpu(|&cpu| {
>                 let remote_ptr = unsafe { ptr.get_remote_ptr(cpu) };
>                 // ...
>         })
> 
> it *might* also be possible to use a macro and dispense with the need for
> a closure, though I'm not familiar enough with proc macros to say for
> sure. That would probably look like
> 
>         for_each_possible_cpu!(cpu) {
>                 let remote_ptr = unsafe { ptr.get_remote_ptr(cpu) };
>                 // ...
>         }
> 
> though personally I think the first one is better (simpler
> implementation without too much syntactic overhead, especially since
> closures are already used some within R4L).

Sure, #1 is OK if you prefer it.