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Date: Thu, 9 Aug 2007 12:27:19 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Subject: Re: [PATCH 17/23] mm: count writeback pages per BDI
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On Thu, 9 Aug 2007, Peter Zijlstra wrote:

> Less conditionals. We already have a branch for mapping, why create
> another?

Ah. Okay. This also avoids an interrupt enable disable since you can use 
__ functions. Hmmm... Would be good if we could move the vmstat 
NR_WRITEBACK update there too. Can a page without a mapping be under 
writeback? (Direct I/O?)