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From:   Marco Elver <elver@google.com>
Date:   Mon, 3 Feb 2020 16:54:47 +0100
Message-ID: <CANpmjNNVstV4AJHtf0aht1xyj+_a-Kj4so4Mi1DpOWDPYN=-2Q@mail.gmail.com>
Subject: Re: Confused about hlist_unhashed_lockless()
To:     David Laight <David.Laight@aculab.com>
Cc:     Eric Dumazet <edumazet@google.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Will Deacon <will@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        "the arch/x86 maintainers" <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Mon, 3 Feb 2020 at 16:45, David Laight <David.Laight@aculab.com> wrote:
>
> From: Eric Dumazet
> > Sent: 31 January 2020 18:53
> >
> > On Fri, Jan 31, 2020 at 10:48 AM Eric Dumazet <edumazet@google.com> wrote:
> > >
> >
> > > This is nice, now with have data_race()
> > >
> > > Remember these patches were sent 2 months ago, at a time we were
> > > trying to sort out things.
> > >
> > > data_race() was merged a few days ago.
> >
> > Well, actually data_race() is not there yet anyway.
>
> Shouldn't it be NO_DATA_RACE() ??

Various options were considered, and based on feedback from Linus,
decided 'data_race(..)' is the best option:
  https://lore.kernel.org/linux-fsdevel/CAHk-=wg5CkOEF8DTez1Qu0XTEFw_oHhxN98bDnFqbY7HL5AB2g@mail.gmail.com/

It's meant to be as unobtrusive as possible, and an all-caps macro was
ruled out.

Second, the "NO_" prefix would be incorrect, since it'd be the
opposite of what it is. The macro is meant to document and mark a
deliberate data race.

Thanks,
-- Marco