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In-Reply-To: <20210707114834.64037813@oasis.local.home>
From: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date: Wed, 7 Jul 2021 18:44:05 +0200
Message-ID: <CANiq72nkNrekzbxMci6vW02w=Q2L-SVTk_U4KN_LT8u_b=YPgw@mail.gmail.com>
Subject: Re: [TECH TOPIC] Rust for Linux
To: Steven Rostedt <rostedt@goodmis.org>
Cc: ksummit@lists.linux.dev, Alex Gaynor <alex.gaynor@gmail.com>
Content-Type: text/plain; charset="UTF-8"

On Wed, Jul 7, 2021 at 5:48 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> BTW, does rust support "fentry/mcount" code? If not, that means ftrace
> (and all the hooks we have inside the kernel) are not going to be able
> to use it? That's one big "notrace" across all drivers that implement
> Rust?

>From a quick look, there seems to be support for `mcount` [1], and an
open issue on `fentry` [2]. Rust is based on LLVM, so anything that we
already do through Clang should be doable in `rustc` too.

I have asked our in-house Rust experts in case they now something more
(thanks Alex for the `fentry` link!).

[1] https://github.com/rust-lang/rust/pull/57220
[2] https://github.com/rust-lang/rust/issues/55092

Cheers,
Miguel