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Subject: Re: [PATCH] Define flush_wc, a way to flush write combining store
	buffers
From: "Bryan O'Sullivan" <bos@pathscale.com>
To: Andi Kleen <ak@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>, akpm@osdl.org,
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On Wed, 2006-03-08 at 15:38 +0100, Andi Kleen wrote:

> Hmm, I reread the thread and with the "i don't need a flush, just ordering" 
> part of your description it makes sense.

Actually, the sfence architecturally guarantees a WC store buffer flush
on x86_64 too, which I need.  Obviously, on CPUs that don't have WC
on-chip, this is not an issue.

> My second objection still stands though. Maybe we should add this as
> part of a generic portable PAT/WC infrastructure. But isolated
> it doesn't make sense.

Fine.  I'll put it in the driver for now, and work on the generic WC
infrastructure in parallel.

	<b

-- 
Bryan O'Sullivan <bos@pathscale.com>

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