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Date: Thu, 9 Mar 2006 11:37:32 +1100
From: Paul Mackerras <paulus@samba.org>
Subject: Re: [PATCH] Document Linux's memory barriers [try #2]
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Sender: linux-arch-owner@vger.kernel.org
To: Matthew Wilcox <matthew@wil.cx>
Cc: Linus Torvalds <torvalds@osdl.org>, David Howells <dhowells@redhat.com>, Alan Cox <alan@redhat.com>, akpm@osdl.org, mingo@redhat.com, linux-arch@vger.kernel.org, linuxppc64-dev@ozlabs.org, linux-kernel@vger.kernel.org
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Matthew Wilcox writes:

> Looking at the SGI implementation, it's smarter than you think.  Looks
> like there's a register in the local I/O hub that lets you determine
> when this write has been queued in the appropriate host->pci bridge.

Given that mmiowb takes no arguments, how does it know which is the
appropriate PCI host bridge?

Paul.