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 for <linuxppc-dev@lists.ozlabs.org>; Wed, 15 Jun 2016 23:14:23 +1000 (AEST)
Date: Wed, 15 Jun 2016 15:14:15 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Gautham R Shenoy <ego@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Tejun Heo <htejun@gmail.com>,
 Michael Ellerman <mpe@ellerman.id.au>,
 Abdul Haleem <abdhalee@linux.vnet.ibm.com>,
 Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>,
 linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] workqueue:Fix affinity of an unbound worker of a
 node with 1 online CPU
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On Wed, Jun 15, 2016 at 06:20:33PM +0530, Gautham R Shenoy wrote:
> We will no longer have the optimization in
> restore_unbound_workers_cpumask() but I suppose we don't lose much by
> resetting the affinity every time a CPU in the pool->attr->cpumask
> comes online.

Right; optimizing hotplug really isn't worth it. The code needs to be
simple and robust (ha! funny).

In any case, Tejun, does this work for you?