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Date:   Wed, 11 Jul 2018 19:00:53 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Will Deacon <will.deacon@arm.com>
Cc:     Andrea Parri <andrea.parri@amarulasolutions.com>,
        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>,
        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
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 <20180711094310.GA13963@arm.com>
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On Wed, Jul 11, 2018 at 04:57:51PM +0100, Will Deacon wrote:

> 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,

Another vote for RCsc locks. The (in)famous hold-out is of course
PowerPC, but it now looks like RISC-V is following where they I really
rather wish they didn't.