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Date:   Thu, 5 Jul 2018 17:09:45 +0200
From:   Andrea Parri <andrea.parri@amarulasolutions.com>
To:     Alan Stern <stern@rowland.harvard.edu>
Cc:     Will Deacon <will.deacon@arm.com>,
        LKMM Maintainers -- Akira Yokosawa <akiyks@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        David Howells <dhowells@redhat.com>,
        Jade Alglave <j.alglave@ucl.ac.uk>,
        Luc Maranget <luc.maranget@inria.fr>,
        Nicholas Piggin <npiggin@gmail.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Kernel development list <linux-kernel@vger.kernel.org>,
        dlustig@nvidia.com
Subject: Re: [PATCH 2/2] tools/memory-model: Add write ordering by
 release-acquire and by locks
Message-ID: <20180705150945.GA3699@andrea>
References: <20180704121103.GB26941@arm.com>
 <Pine.LNX.4.44L0.1807051010380.1697-100000@iolanthe.rowland.org>
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> At any rate, it looks like instead of strengthening the relation, I
> should write a patch that removes it entirely.  I also will add new,
> stronger relations for use with locking, essentially making spin_lock
> and spin_unlock be RCsc.

Thank you.

Ah let me put this forward: please keep an eye on the (generic)

  queued_spin_lock()
  queued_spin_unlock()

(just to point out an example). Their implementation (in part.,
the fast-path) suggests that if we will stick to RCsc lock then
we should also stick to RCsc acq. load from RMW and rel. store.

  Andrea


> 
> Alan
>