Received-SPF: pass (google.com: domain of linux-kernel+bounces-204928-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
Feedback-ID: iad51458e:Fastmail
Date: Thu, 6 Jun 2024 12:00:36 -0700
From: Boqun Feng <boqun.feng@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Alice Ryhl <aliceryhl@google.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Josh Poimboeuf <jpoimboe@kernel.org>,
	Jason Baron <jbaron@akamai.com>, Ard Biesheuvel <ardb@kernel.org>,
	Miguel Ojeda <ojeda@kernel.org>,
	Alex Gaynor <alex.gaynor@gmail.com>,
	Wedson Almeida Filho <wedsonaf@gmail.com>,
	Gary Guo <gary@garyguo.net>,
	=?iso-8859-1?Q?Bj=F6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
	Benno Lossin <benno.lossin@proton.me>,
	Andreas Hindborg <a.hindborg@samsung.com>,
	linux-trace-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/3] rust: add tracepoint support
Message-ID: <ZmIHVIqEukWWRMgd@boqun-archlinux>
References: <20240606-tracepoint-v1-0-6551627bf51b@google.com>
 <20240606-tracepoint-v1-3-6551627bf51b@google.com>
 <389a8c55-a169-47ef-99c0-48f58003b40c@efficios.com>
 <ZmHacqvRwBj7OvWm@boqun-archlinux>
 <20240606173544.GI8774@noisy.programming.kicks-ass.net>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20240606173544.GI8774@noisy.programming.kicks-ass.net>

On Thu, Jun 06, 2024 at 07:35:44PM +0200, Peter Zijlstra wrote:
> On Thu, Jun 06, 2024 at 08:49:06AM -0700, Boqun Feng wrote:
> 
> > Long-term plan is to 1) compile the C helpers in some IR and 2) inline
> > the helpers with Rust in IR-level, as what Gary has:
> > 
> > 	https://lore.kernel.org/rust-for-linux/20240529202817.3641974-1-gary@garyguo.net/
> 
> Urgh, that still needs us to maintain that silly list of helpers :-/
> 

But it's an improvement from the current stage, right? ;-)

> Can't we pretty please have clang parse the actual header files into IR
> and munge that into rust? So that we don't get to manually duplicate
> everything+dog.

That won't always work, because some of our kernel APIs are defined as
macros, and I don't think it's a trivial job to generate a macro
definition to a function definition so that it can be translated to
something in IR. We will have to do the macro -> function mapping
ourselves somewhere, if we want to inline the API across languages.

Regards,
Boqun