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Date:   Fri, 19 Apr 2019 02:53:02 +0200
From:   Andrea Parri <andrea.parri@amarulasolutions.com>
To:     Alan Stern <stern@rowland.harvard.edu>
Cc:     "Paul E. McKenney" <paulmck@linux.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>,
        Will Deacon <will.deacon@arm.com>,
        Daniel Kroening <kroening@cs.ox.ac.uk>,
        Kernel development list <linux-kernel@vger.kernel.org>
Subject: Re: Adding plain accesses and detecting data races in the LKMM
Message-ID: <20190419005302.GA5311@andrea>
References: <20190418125412.GA10817@andrea>
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> Are you saying that on x86, atomic_inc() acts as a full memory barrier 
> but not as a compiler barrier, and vice versa for 
> smp_mb__after_atomic()?  Or that neither atomic_inc() nor 
> smp_mb__after_atomic() implements a full memory barrier?

I'd say the former; AFAICT, these boil down to:

  https://elixir.bootlin.com/linux/v5.1-rc5/source/arch/x86/include/asm/atomic.h#L95
  https://elixir.bootlin.com/linux/v5.1-rc5/source/arch/x86/include/asm/barrier.h#L84

  Andrea