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Date: Thu, 14 Aug 2014 09:35:37 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
To: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Subject: Re: [RFC PATCH v3 1/4] topology: add support for node_to_mem_node()
 to determine the fallback node
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Cc: Han Pingtian <hanpt@linux.vnet.ibm.com>, Matt Mackall <mpm@selenic.com>,
 Pekka Enberg <penberg@kernel.org>,
 Linux Memory Management List <linux-mm@kvack.org>,
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On Wed, 13 Aug 2014, Nishanth Aravamudan wrote:

> +++ b/include/linux/topology.h
> @@ -119,11 +119,20 @@ static inline int numa_node_id(void)
>   * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem().
>   */
>  DECLARE_PER_CPU(int, _numa_mem_);
> +extern int _node_numa_mem_[MAX_NUMNODES];

Why are these variables starting with an _ ?
Maybe _numa_mem was defined that way because it is typically not defined.
We dont do this in other situations.