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From: Daniel Phillips <phillips@phunq.net>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH 00/10] foundations for reserve-based allocation
Date: Mon, 6 Aug 2007 12:31:04 -0700
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Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
       David Miller <davem@davemloft.net>,
       Andrew Morton <akpm@linux-foundation.org>,
       Daniel Phillips <phillips@google.com>,
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       Lee Schermerhorn <Lee.Schermerhorn@hp.com>,
       Steve Dickson <SteveD@redhat.com>
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On Monday 06 August 2007 11:17, Peter Zijlstra wrote:
> And how do we know a page was taken out of the reserves?

Why not return that in the low bit of the page address?  This is a 
little more cache efficient, does not leave that odd footprint in the 
page union and forces the caller to examine the 
alloc_pages(...P_MEMALLOC) return, making it harder to overlook the 
fact that it got a page out of reserve and forget to put one back 
later.

Regards,

Daniel