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Subject: Re: [PATCH 0/8] v2 De-Couple sysfs memory directories from memory
	sections
From: Dave Hansen <dave@linux.vnet.ibm.com>
To: Avi Kivity <avi@redhat.com>
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Date: Tue, 28 Sep 2010 08:17:36 -0700
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Cc: linuxppc-dev@ozlabs.org, Greg KH <greg@kroah.com>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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On Tue, 2010-09-28 at 14:44 +0200, Avi Kivity wrote:
> Why not update sysfs directory creation to be fast, for example by using 
> an rbtree instead of a linked list.  This fixes an implementation 
> problem in the kernel instead of working around it and creating a new ABI.
> 
> New ABIs mean old tools won't work, and new tools need to understand 
> both ABIs.

Just to be clear _these_ patches do not change the existing ABI.

They do add a new ABI: the end_phys_index file.  But, it is completely
redundant at the moment.  It could be taken out of these patches.

That said, fixing the directory creation speed is probably a worthwhile
endeavor too.

-- Dave