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Date: Tue, 4 Feb 2014 16:57:44 -0800 (PST)
From: David Rientjes <rientjes@google.com>
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To: Christoph Lameter <cl@linux.com>
cc: Vladimir Davydov <vdavydov@parallels.com>, akpm@linux-foundation.org,
        penberg@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] slub: fix false-positive lockdep warning in
 free_partial()
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On Tue, 4 Feb 2014, Christoph Lameter wrote:

> > Although this cannot actually result in a race, because on cache
> > destruction there should not be any concurrent frees or allocations from
> > the cache, let's add spin_lock/unlock to free_partial() just to keep
> > lockdep happy.
> 
> Please add a comment that says this in the source so we know why this was
> added.
> 

Makes sense since there is a comment there already saying we don't need 
the lock, then with this patch we end up taking it away.  The nice thing 
is that there should be no lock contention here :)

I'm not sure we need to disable irqs as in the patch, though.