Date: Fri, 14 Apr 2017 13:18:03 +0900
From: Tejun Heo <tj@kernel.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
        Sebastian Siewior <bigeasy@linutronix.de>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        "David S. Miller" <davem@davemloft.net>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        Lai Jiangshan <jiangshanlai@gmail.com>, Len Brown <lenb@kernel.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Tony Luck <tony.luck@intel.com>,
        Viresh Kumar <viresh.kumar@linaro.org>
Subject: Re: [patch 02/13] workqueue: Provide work_on_cpu_safe()
Message-ID: <20170414041803.GA13899@wtj.duckdns.org>
References: <20170412200726.941336635@linutronix.de>
 <20170412201042.262610721@linutronix.de>
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On Wed, Apr 12, 2017 at 10:07:28PM +0200, Thomas Gleixner wrote:
> work_on_cpu() is not protected against CPU hotplug. For code which requires
> to be either executed on an online CPU or to fail if the CPU is not
> available the callsite would have to protect against CPU hotplug.
> 
> Provide a function which does get/put_online_cpus() around the call to
> work_on_cpu() and fails the call with -ENODEV if the target CPU is not
> online.
> 
> Preparatory patch to convert several racy task affinity manipulations.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Tejun Heo <tj@kernel.org>
> Cc: Lai Jiangshan <jiangshanlai@gmail.com>

Acked-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun