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Message-ID: <1442592934.7946.22.camel@edumazet-glaptop2.roam.corp.google.com>
Subject: Re: [PATCH] kernel: fix data race in put_pid
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>, Dmitry Vyukov <dvyukov@google.com>,
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        Hans Boehm <hboehm@google.com>
Date: Fri, 18 Sep 2015 09:15:34 -0700
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On Fri, 2015-09-18 at 13:22 +0200, Peter Zijlstra wrote:

...

>  
> +#ifndef atomic_read_ctrl
> +static inline int atomic_read_ctrl(atomic_t *v)

const atomic_t *v

> +{
> +	int val = atomic_read(v);
> +	smp_read_barrier_depends(); /* Enforce control dependency. */
> +	return val;
> +}
> +#endif