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Date: Thu, 9 Dec 2004 02:09:19 -0800
From: Andrew Morton <akpm@osdl.org>
To: Steve Lord <lord@xfs.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: negative dentry_stat.nr_unused causes aggressive dcache pruning
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Steve Lord <lord@xfs.org> wrote:
>
> I have seen this stat go negative (just from booting up a multi cpu box),
>  and looking at the code, it is manipulated without locking in a number
>  of places. I have only seen this in real life on a 2.4 kernel, but 2.6
>  also looks vulnerable.

In 2.6, both dentry_stat.nr_unused and dentry_stat.nr_dentry are covered
by dcache_lock.  I just double-checked and all seems well.