Re: [PATCH 03/13] rust: lock: introduce `Mutex`

[Boqun Feng]

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@xxxxxxxxxxxxx>
> > 
> > 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