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Date: Mon, 19 Mar 2018 08:14:47 -0700
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH] percpu: Allow to kill tasks doing pcpu_alloc() and
 waiting for pcpu_balance_workfn()
Message-ID: <20180319151447.GL2943022@devbig577.frc2.facebook.com>
References: <152102825828.13166.9574628787314078889.stgit@localhost.localdomain>
 <20180314135631.3e21b31b154e9f3036fa6c52@linux-foundation.org>
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To: Andrew Morton <akpm@linux-foundation.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>, cl@linux.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org

On Wed, Mar 14, 2018 at 01:56:31PM -0700, Andrew Morton wrote:
> > +	if (!is_atomic) {
> > +		if (gfp & __GFP_NOFAIL)
> > +			mutex_lock(&pcpu_alloc_mutex);
> > +		else if (mutex_lock_killable(&pcpu_alloc_mutex))
> > +			return NULL;
> > +	}
> 
> It would benefit from a comment explaining why we're doing this (it's
> for the oom-killer).

And, yeah, this would be great.  Kirill, can you please send a patch
to add a comment there?

Thanks.

-- 
tejun