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Date: Wed, 5 Feb 2014 17:26:35 -0800 (PST)
From: David Rientjes <rientjes@google.com>
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To: Steven Rostedt <rostedt@goodmis.org>
cc: LKML <linux-kernel@vger.kernel.org>, Pekka Enberg <penberg@kernel.org>,
        Christoph Lameter <cl@linux.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vladimir Davydov <vdavydov@parallels.com>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH] slub: Do not assert not having lock in removing freed
 partial
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On Wed, 5 Feb 2014, Steven Rostedt wrote:

> > We'll want to do something similiar for the add_partial() called from
> > early_kmem_cache_node_alloc(), right?  It had the added n->list_lock for 
> > the same reason and is done during early init where nobody else can be 
> > referencing a kmem_cache_node.
> > 
> > It would probably be better to define these in terms of "partial slabs 
> > that cannot have anyone else accessing it" rather than "freed slabs".
> 
> Perhaps then we just use the __remove_partial() and __add_partial()
> that does not do the checks. That's common practice to use a "__" to
> denote that it's special and usually doesn't require locking.
> 

Sounds appropriate.  Andrew released a mmotm today so I'm assuming it will 
be in linux-next tomorrow with my {add,remove}_full() patch but it 
shouldn't matter if you're going to be playing with 
{add,remove}_partial().