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From: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date: Fri, 9 Jul 2021 01:09:54 +0200
Message-ID: <CANiq72nt7yD2kVjq9mUt+M5eVqfpvaPrZbaGZp1ftWJX3J7FXw@mail.gmail.com>
Subject: Re: [TECH TOPIC] Rust for Linux
To: Greg KH <greg@kroah.com>
Cc: Wedson Almeida Filho <wedsonaf@google.com>, Jan Kara <jack@suse.cz>, 
	James Bottomley <James.Bottomley@hansenpartnership.com>, 
	Julia Lawall <julia.lawall@inria.fr>, 
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>, 
	Linus Walleij <linus.walleij@linaro.org>, Roland Dreier <roland@kernel.org>, ksummit@lists.linux.dev
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On Thu, Jul 8, 2021 at 8:44 PM Greg KH <greg@kroah.com> wrote:
>
> kref does not contain the lock, but you need to use a lock lots of time
> when dealing with them.  See my response to Andy for why.

A lock may be needed in certain scenarios, but that is because
something else is involved -- i.e. to maintain the refcount itself we
don't need a lock.

Let me give an inefficient, unrealistic counter-example: we could use
an atomic with sequential consistency for the refcount.

Cheers,
Miguel