From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Hansen <dave.hansen@intel.com>
Subject: Re: [PATCH v6 07/11] VFS hot tracking: Add a /proc interface to control
 memory usage
Date: Mon, 11 Nov 2013 14:15:00 -0800
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Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>,
	Chandra Seetharaman <sekharan@us.ibm.com>
To: Zhi Yong Wu <zwu.kernel@gmail.com>, viro@zeniv.linux.org.uk
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On 11/06/2013 05:45 AM, Zhi Yong Wu wrote:
> Introduce a /proc interface hot-mem-high-thresh and
> to cap the memory which is consumed by hot_inode_item
> and hot_range_item, and they will be in the unit of
> 1M bytes.

You don't seem to have any documentation for this, btw... :(

> +		.procname       = "hot-mem-high-thresh",

*Always* put units on these.  I know you mention it in a code comment,
but please also include it in the proc filename too.

In general, why do you have to control the number of these statically?
Shouldn't you just define a shrinker and let memory pressure determine
how many of these we allow to exist?