From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Date: Wed, 20 Sep 2006 20:23:25 +0000
Subject: Re: [PATCH] export cpu_sibling_map
Message-Id: <20060920202325.GB22954@infradead.org>
List-Id: <linux-ia64.vger.kernel.org>
References: <20060920195347.GD27323@frankl.hpl.hp.com>
In-Reply-To: <20060920195347.GD27323@frankl.hpl.hp.com>
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To: linux-ia64@vger.kernel.org

On Wed, Sep 20, 2006 at 12:53:47PM -0700, Stephane Eranian wrote:
> Hello Tony,
> 
> For Montecito PMU support, I need to determine, in a kernel module, whether
> or not threads are enabled. The only reliable way of doing this is to
> compute the bit-weight of cpu_sibling_map[]. This symbol is exported on
> x86 systems, but not on IA-64 so far. This patch exports the symbol.

Exporting global variables is a very bad thing, and we only do it if we
can't avoid it at all.  In this case it could be easily avoided by
exporting a nr_siblings_per_cpu() helper.