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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu, 12 Jul 2018 11:10:58 -0700
Message-ID: <CA+55aFxwez8zSa2f2GpcaAkFX27Vt-s0nWdd0mZ6yGM8ipCR0A@mail.gmail.com>
Subject: Re: [PATCH v2] tools/memory-model: Add extra ordering for locks and
 remove it for ordinary release/acquire
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Paul McKenney <paulmck@linux.vnet.ibm.com>,
        Alan Stern <stern@rowland.harvard.edu>,
        andrea.parri@amarulasolutions.com,
        Will Deacon <will.deacon@arm.com>,
        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>,
        Nick Piggin <npiggin@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, Jul 12, 2018 at 11:05 AM Peter Zijlstra <peterz@infradead.org> wrote:
>
> The locking pattern is fairly simple and shows where RCpc comes apart
> from expectation real nice.

So who does RCpc right now for the unlock-lock sequence? Somebody
mentioned powerpc. Anybody else?

How nasty would be be to make powerpc conform? I will always advocate
tighter locking and ordering rules over looser ones..

           Linus