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Date:   Fri, 16 Aug 2019 16:49:12 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Joel Fernandes <joel@joelfernandes.org>
Cc:     Alan Stern <stern@rowland.harvard.edu>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Valentin Schneider <valentin.schneider@arm.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        paulmck <paulmck@linux.ibm.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        Will Deacon <will.deacon@arm.com>,
        David Howells <dhowells@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 1/1] Fix: trace sched switch start/stop racy updates
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On Fri, 16 Aug 2019 16:44:10 -0400
Joel Fernandes <joel@joelfernandes.org> wrote:


> I am also more on the side of using *_ONCE. To me, by principal, I
> would be willing to convert any concurrent plain access using _ONCE,
> just so we don't have to worry about it now or in the future and also
> documents the access.
> 
> Perhaps the commit message can be reworded to mention that the _ONCE
> is an additional clean up for safe access.

The most I'll take is two separate patches. One is going to be marked
for stable as it fixes a real bug. The other is more for cosmetic or
theoretical issues, that I will state clearly "NOT FOR STABLE", such
that the autosel doesn't take them.

-- Steve