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Date:   Sat, 15 Jul 2023 10:14:57 +0200
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Subject: Re: [PATCH v2] rust: time: New module for timekeeping functions
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To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org,
        asahi@lists.linux.dev, Asahi Lina <lina@asahilina.net>,
        Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?UTF-8?Q?Bj=c3=b6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
        John Stultz <jstultz@google.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Josh Stone <jistone@redhat.com>,
        Gaelan Steele <gbs@canishe.com>,
        Heghedus Razvan <heghedus.razvan@protonmail.com>
References: <20230714-rust-time-v2-1-f5aed84218c4@asahilina.net>
 <87r0pax9a6.ffs@tglx>
From:   Alice Ryhl <alice@ryhl.io>
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On 7/15/23 03:17, Thomas Gleixner wrote:
> On Fri, Jul 14 2023 at 16:55, Asahi Lina wrote:
>> +ktime_t rust_helper_ktime_get_real(void) {
>> +	return ktime_get_real();
>> +}
>> +EXPORT_SYMBOL_GPL(rust_helper_ktime_get_real);
> 
> Colour me confused. But why does this need another export?
> 
> This just creates yet another layer of duct tape. If it's unsafe from
> the rust perspective then wrapping it into rust_"unsafe_function" does not
> make it any better.
> 
> Why on earth can't you use the actual C interfaces diretly which are
> already exported?

Currently, you can't call inline C functions directly from Rust. So we 
wrap them in non-inline functions for now.

It's something we definitely want to fix, but it hasn't been fixed yet.

Alice