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Date:   Thu, 30 Mar 2023 11:47:12 -0700
From:   Boqun Feng <boqun.feng@gmail.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Wedson Almeida Filho <wedsonaf@gmail.com>,
        rust-for-linux@vger.kernel.org, Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Gary Guo <gary@garyguo.net>,
        =?iso-8859-1?Q?Bj=F6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
        linux-kernel@vger.kernel.org,
        Wedson Almeida Filho <walmeida@microsoft.com>,
        Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
        Waiman Long <longman@redhat.com>
Subject: Re: [PATCH 03/13] rust: lock: introduce `Mutex`
Message-ID: <ZCXZMNj7aOKbC7Ev@boqun-archlinux>
References: <20230330043954.562237-1-wedsonaf@gmail.com>
 <20230330043954.562237-3-wedsonaf@gmail.com>
 <20230330130108.GE124812@hirez.programming.kicks-ass.net>
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On Thu, Mar 30, 2023 at 03:01:08PM +0200, Peter Zijlstra wrote:
> On Thu, Mar 30, 2023 at 01:39:44AM -0300, Wedson Almeida Filho wrote:
> > From: Wedson Almeida Filho <walmeida@microsoft.com>
> > 
> > This is the `struct mutex` lock backend and allows Rust code to use the
> > kernel mutex idiomatically.
> 
> What, if anything, are the plans to support the various lockdep
> annotations? Idem for the spinlock thing in the other patch I suppose.

FWIW:

*	At the init stage, SpinLock and Mutex in Rust use initializers
	that are aware of the lockdep, so everything (lockdep_map and
	lock_class) is all set up.

*	At acquire or release time, Rust locks just use ffi to call C
	functions that have lockdep annotations in them, so lockdep
	should just work.

In fact, I shared some same worry as you, so I already work on adding
lockdep selftests for Rust lock APIs, will send them shortly, although
they are just draft.

Regards,
Boqun