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Date: Mon, 16 May 2016 19:02:57 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: mingo@kernel.org, linux-kernel@vger.kernel.org, clm@fb.com,
        matt@codeblueprint.co.uk, mgalbraith@suse.de, tglx@linutronix.de,
        fweisbec@gmail.com
Subject: Re: [RFC][PATCH 4/7] sched: Replace sd_busy/nr_busy_cpus with
 sched_domain_shared
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On Mon, May 16, 2016 at 04:31:08PM +0100, Dietmar Eggemann wrote:
> On 09/05/16 11:48, Peter Zijlstra wrote:
> 
> Couldn't you just always access sd->shared via
> sd = rcu_dereference(per_cpu(sd_llc, cpu)) for
> updating nr_busy_cpus?

Sure; but why would I want to add that extra dereference? Note that in
the next patch I add more users of sd_llc_shared.