From: Jesse Barnes <jbarnes@virtuousgeek.org>
To: Linus Torvalds <torvalds@osdl.org>
Cc: 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
Subject: Re: [PATCH] Document Linux's memory barriers [try #2]
Date: Wed, 8 Mar 2006 11:54:21 -0800 [thread overview]
Message-ID: <200603081154.21960.jbarnes@virtuousgeek.org> (raw)
In-Reply-To: <Pine.LNX.4.64.0603081115300.32577@g5.osdl.org>
On Wednesday, March 8, 2006 11:26 am, Linus Torvalds wrote:
> But if you have a separate IO fabric and basically two different CPU's
> can get to one device through two different paths, no amount of write
> barriers of any kind will ever help you.
No, that's exactly the case that mmiowb() was designed to protect
against. It ensures that your writes have arrived at the destination
bridge, which means after that point any other CPUs writing to the same
device will have their data actually hit the device afterwards.
Hopefully deviceiobook.tmpl makes that clear...
Jesse
next prev parent reply other threads:[~2006-03-08 19:54 UTC|newest]
Thread overview: 89+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-03-07 17:40 [PATCH] Document Linux's memory barriers David Howells
2006-03-07 10:34 ` Andi Kleen
2006-03-07 18:30 ` David Howells
2006-03-07 11:13 ` Andi Kleen
2006-03-07 19:24 ` David Howells
2006-03-07 18:46 ` Jesse Barnes
2006-03-07 19:23 ` Bryan O'Sullivan
2006-03-07 11:57 ` Andi Kleen
2006-03-07 20:01 ` Jesse Barnes
2006-03-07 21:14 ` Bryan O'Sullivan
2006-03-07 21:24 ` Andi Kleen
2006-03-08 0:36 ` Alan Cox
2006-03-08 0:35 ` Alan Cox
2006-03-07 18:40 ` Alan Cox
2006-03-07 18:54 ` linux-os (Dick Johnson)
2006-03-07 19:06 ` Matthew Wilcox
2006-03-07 19:15 ` linux-os (Dick Johnson)
2006-03-07 19:33 ` Alan Cox
2006-03-07 20:09 ` David Howells
2006-03-08 0:32 ` Alan Cox
2006-03-08 8:25 ` Duncan Sands
2006-03-08 22:06 ` Paul Mackerras
2006-03-08 22:24 ` David S. Miller
2006-03-08 22:31 ` Linus Torvalds
2006-03-08 22:42 ` Alan Cox
2006-03-08 2:07 ` Nick Piggin
2006-03-08 3:10 ` Paul Mackerras
2006-03-08 3:30 ` Linus Torvalds
2006-03-08 12:34 ` David Howells
2006-03-08 16:40 ` Bryan O'Sullivan
2006-03-08 7:41 ` Nick Piggin
2006-03-08 13:19 ` David Howells
2006-03-08 21:49 ` Paul Mackerras
2006-03-08 22:05 ` Alan Cox
2006-03-08 14:37 ` [PATCH] Document Linux's memory barriers [try #2] David Howells
2006-03-08 14:55 ` Alan Cox
2006-03-08 15:41 ` Matthew Wilcox
2006-03-08 17:19 ` David Howells
2006-03-08 22:10 ` Paul Mackerras
2006-03-08 23:08 ` Ivan Kokshaysky
2006-03-09 1:01 ` Paul Mackerras
2006-03-09 16:02 ` Ivan Kokshaysky
2006-03-08 17:04 ` David Howells
2006-03-08 17:36 ` Alan Cox
2006-03-08 18:35 ` David Howells
2006-03-08 18:45 ` Alan Cox
2006-03-08 18:59 ` David Howells
2006-03-08 11:38 ` Andi Kleen
2006-03-08 19:08 ` David Howells
2006-03-08 19:26 ` Linus Torvalds
2006-03-08 19:31 ` David Howells
2006-03-09 0:35 ` Paul Mackerras
2006-03-09 0:54 ` Linus Torvalds
2006-03-09 1:08 ` Paul Mackerras
2006-03-09 1:27 ` Linus Torvalds
2006-03-09 2:38 ` Nick Piggin
2006-03-09 3:45 ` Paul Mackerras
2006-03-09 4:36 ` Jesse Barnes
2006-03-09 7:41 ` Paul Mackerras
2006-03-09 5:38 ` Linus Torvalds
2006-03-09 12:27 ` David Howells
2006-03-09 11:44 ` Michael Buesch
2006-03-09 4:34 ` Jesse Barnes
2006-03-09 4:43 ` Paul Mackerras
2006-03-09 10:05 ` Jes Sorensen
2006-03-09 0:55 ` Jesse Barnes
2006-03-09 1:57 ` Paul Mackerras
2006-03-09 4:26 ` Jesse Barnes
2006-03-08 19:40 ` Matthew Wilcox
2006-03-09 0:37 ` Paul Mackerras
2006-03-09 0:59 ` Jesse Barnes
2006-03-09 1:36 ` Paul Mackerras
2006-03-09 4:18 ` Jesse Barnes
2006-03-08 19:54 ` Jesse Barnes [this message]
2006-03-08 20:02 ` Alan Cox
2006-03-08 22:01 ` Paul Mackerras
2006-03-08 22:23 ` David S. Miller
2006-03-08 19:37 ` [PATCH] Document Linux's memory barriers [try #3] David Howells
2006-03-09 14:01 ` David Howells
2006-03-08 16:18 ` [PATCH] Document Linux's memory barriers Pavel Machek
2006-03-08 20:16 ` David Howells
2006-03-08 22:01 ` Alan Cox
2006-03-09 11:41 ` David Howells
2006-03-09 12:28 ` Alan Cox
2006-03-09 13:02 ` David Howells
2006-03-09 16:32 ` Linus Torvalds
2006-03-09 17:39 ` David Howells
2006-03-09 17:54 ` Linus Torvalds
2006-03-09 17:56 ` Linus Torvalds
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