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Date:   Fri, 1 Dec 2023 10:40:37 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Boqun Feng <boqun.feng@gmail.com>
Cc:     Matthew Wilcox <willy@infradead.org>,
        Alice Ryhl <aliceryhl@google.com>,
        Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
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        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>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <brauner@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Arve =?iso-8859-1?B?SGr4bm5lduVn?= <arve@android.com>,
        Todd Kjos <tkjos@android.com>,
        Martijn Coenen <maco@android.com>,
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        Carlos Llamas <cmllamas@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
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        Kees Cook <keescook@chromium.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Daniel Xu <dxu@dxuuu.xyz>, linux-kernel@vger.kernel.org,
        rust-for-linux@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Josh Triplett <josh@joshtriplett.org>
Subject: Re: [PATCH 1/7] rust: file: add Rust abstraction for `struct file`
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On Fri, Dec 01, 2023 at 01:19:14AM -0800, Boqun Feng wrote:

> > > 	https://github.com/Amanieu/rfcs/blob/inline-asm/text/0000-inline-asm.md#asm-goto
> > 
> > Reading that makes all this even worse, apparently rust can't even use
> > memops.
> 
> What do you mean by "memops"?

Above link has the below in "future possibilities":

"Memory operands

We could support mem as an alternative to specifying a register class
which would leave the operand in memory and instead produce a memory
address when inserted into the asm string. This would allow generating
more efficient code by taking advantage of addressing modes instead of
using an intermediate register to hold the computed address."

Just so happens that every x86 atomic block uses memops.. and per-cpu
and ...