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Date:   Tue, 6 Oct 2020 18:10:39 +0200
From:   Willy Tarreau <w@1wt.eu>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     David Laight <David.Laight@ACULAB.COM>,
        "'Nick Clifton'" <nickc@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        "stern@rowland.harvard.edu" <stern@rowland.harvard.edu>,
        "linux-toolchains@vger.kernel.org" <linux-toolchains@vger.kernel.org>,
        Will Deacon <will@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "parri.andrea@gmail.com" <parri.andrea@gmail.com>,
        "boqun.feng@gmail.com" <boqun.feng@gmail.com>,
        "npiggin@gmail.com" <npiggin@gmail.com>,
        "dhowells@redhat.com" <dhowells@redhat.com>,
        "j.alglave@ucl.ac.uk" <j.alglave@ucl.ac.uk>,
        "luc.maranget@inria.fr" <luc.maranget@inria.fr>,
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        "joel@joelfernandes.org" <joel@joelfernandes.org>,
        "torvalds@linux-foundation.org" <torvalds@linux-foundation.org>
Subject: Re: Control Dependencies vs C Compilers
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On Tue, Oct 06, 2020 at 08:50:52AM -0700, Paul E. McKenney wrote:
> Comparing 25+ assembly languages to but two compilers most definitely
> motivates looking hard at doing something with the compilers.

+1, especially since the kernel is not special; anyone working with
threads faces the same issues in userland, which are often hidden
behind the implicit whole-memory clobbers of certain operations or
the call to mutex manipulation functions, but which become a reality
again as soon as you go slightly away from these and try to use
lockless mechanisms.

Willy