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Date: Fri, 9 Jun 2006 19:42:36 -0700
From: Andrew Morton <akpm@osdl.org>
To: rohitseth@google.com
Cc: Linux-mm@kvack.org, Linux-kernel@vger.kernel.org
Subject: Re: [PATCH]: Adding a counter in vma to indicate the number of
 physical pages backing it
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On Fri, 09 Jun 2006 18:33:55 -0700
Rohit Seth <rohitseth@google.com> wrote:

> Below is a patch that adds number of physical pages that each vma is
> using in a process.  Exporting this information to user space
> using /proc/<pid>/maps interface.

Ouch, that's an awful lot of open-coded incs and decs.  Isn't there some
more centralised place we can do this?

What locking protects vma.nphys (can we call this nr_present or something?)

Will this patch do the right thing with weird vmas such as the gate vma and
mmaps of device memory, etc?