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Date:   Wed, 11 Jul 2018 18:28:04 +0200
From:   Andrea Parri <andrea.parri@amarulasolutions.com>
To:     Will Deacon <will.deacon@arm.com>
Cc:     Alan Stern <stern@rowland.harvard.edu>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        LKMM Maintainers -- Akira Yokosawa <akiyks@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        Daniel Lustig <dlustig@nvidia.com>,
        David Howells <dhowells@redhat.com>,
        Jade Alglave <j.alglave@ucl.ac.uk>,
        Luc Maranget <luc.maranget@inria.fr>,
        Nicholas Piggin <npiggin@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Kernel development list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] tools/memory-model: Add extra ordering for locks and
 remove it for ordinary release/acquire
Message-ID: <20180711162804.GA15081@andrea>
References: <Pine.LNX.4.44L0.1807091519180.2462-100000@iolanthe.rowland.org>
 <20180710093821.GA5414@andrea>
 <20180711094310.GA13963@arm.com>
 <20180711123421.GA9673@andrea>
 <20180711155751.GC18477@arm.com>
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> It might be simple to model, but I worry this weakens our locking
> implementations to a point where they will not be understood by the average
> kernel developer. As I've said before, I would prefer "full" RCsc locking,
> but that's not the case with architectures we currently support today, so
> the next best thing is this "everything apart from W->R in the
> inter-thread case" ordering, which isn't going to crop up unless you're
> doing weird stuff anyway afaict.

The "average kernel developer" thinks TSO or about, right?  ;-)

  Andrea


> 
> Will