From: Tejun Heo <tj@kernel.org>
To: David Rientjes <rientjes@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>, Ingo Molnar <mingo@elte.hu>,
tglx@linutronix.de, "H. Peter Anvin" <hpa@zytor.com>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH x86/mm UPDATED] x86-64, NUMA: Fix distance table handling
Date: Fri, 4 Mar 2011 15:32:56 +0100 [thread overview]
Message-ID: <20110304143256.GR20499@htj.dyndns.org> (raw)
In-Reply-To: <alpine.DEB.2.00.1103031205070.9993@chino.kir.corp.google.com>
Hello,
On Thu, Mar 03, 2011 at 12:07:10PM -0800, David Rientjes wrote:
> The new emulation code needs to remove the assumption that node 0 always
> is online and become more robust since there's no such restriction in the
> ACPI spec.
Yeah, indeed, that's possible. ACPI spec isn't really the deciding
factor here. The node IDs are purely software and a system is
required to have at least one node, so it seems reasonable to require
node 0 to be always online - or even to require all online node IDs to
be consecutive starting from 0. The only reason we may have holes in
node IDs now is because PXM -> nid mapping isn't released for empty
memory-only nodes.
The biggest downside of deferring checks for this type of rare
conditions to upper layers when not strictly necessary is that it
tends to lead to one-off bugs which trigger very infrequently.
That said, maybe we're already too deep toward that direction and it's
much easier to weed out the assumptions that node0 is always online.
Thanks.
--
tejun
next prev parent reply other threads:[~2011-03-04 14:33 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-24 14:51 [GIT PULL tip:x86/mm] Tejun Heo
2011-02-24 14:52 ` [GIT PULL tip:x86/mm] bootmem,x86: cleanup changes Tejun Heo
2011-02-24 19:08 ` [GIT PULL tip:x86/mm] Yinghai Lu
2011-02-24 19:23 ` Ingo Molnar
2011-02-24 19:28 ` Yinghai Lu
2011-02-24 19:32 ` Ingo Molnar
2011-02-24 19:46 ` Tejun Heo
2011-02-24 22:46 ` [patch] x86, mm: Fix size of numa_distance array David Rientjes
2011-02-24 23:30 ` Yinghai Lu
2011-02-24 23:31 ` David Rientjes
2011-02-25 9:05 ` Tejun Heo
2011-02-25 9:03 ` Tejun Heo
2011-02-25 10:58 ` Tejun Heo
2011-02-25 11:05 ` Tejun Heo
2011-02-25 9:11 ` [PATCH x86-mm] x86-64, NUMA: " Tejun Heo
2011-03-01 17:18 ` [GIT PULL tip:x86/mm] David Rientjes
2011-03-01 18:25 ` Tejun Heo
2011-03-01 22:19 ` Yinghai Lu
2011-03-02 9:17 ` Tejun Heo
2011-03-02 10:04 ` [PATCH x86/mm] x86-64, NUMA: Fix distance table handling Tejun Heo
2011-03-02 10:07 ` Ingo Molnar
2011-03-02 10:15 ` Tejun Heo
2011-03-02 10:36 ` Ingo Molnar
2011-03-02 10:25 ` [PATCH x86/mm UPDATED] " Tejun Heo
2011-03-02 10:39 ` [PATCH x86/mm] x86-64, NUMA: Better explain numa_distance handling Tejun Heo
2011-03-02 10:42 ` [PATCH UPDATED " Tejun Heo
2011-03-02 14:31 ` David Rientjes
2011-03-02 14:30 ` [PATCH x86/mm UPDATED] x86-64, NUMA: Fix distance table handling David Rientjes
2011-03-02 15:42 ` Tejun Heo
2011-03-02 21:12 ` Yinghai Lu
2011-03-02 21:36 ` Yinghai Lu
2011-03-03 20:07 ` David Rientjes
2011-03-04 14:32 ` Tejun Heo [this message]
2011-03-03 20:04 ` David Rientjes
2011-03-03 20:00 ` David Rientjes
2011-03-04 15:31 ` [PATCH x86/mm] x86-64, NUMA: Don't assume phys node 0 is always online in numa_emulation() handling Tejun Heo
2011-03-04 21:33 ` David Rientjes
2011-03-05 7:50 ` Tejun Heo
2011-03-05 15:50 ` [tip:x86/mm] x86-64, NUMA: Don't assume phys node 0 is always online in numa_emulation() tip-bot for Tejun Heo
2011-03-02 16:16 ` [PATCH x86/mm UPDATED] x86-64, NUMA: Fix distance table handling Yinghai Lu
2011-03-02 16:37 ` Tejun Heo
2011-03-02 16:46 ` Yinghai Lu
2011-03-02 16:55 ` Tejun Heo
2011-03-02 18:52 ` Yinghai Lu
2011-03-02 19:02 ` Tejun Heo
2011-03-02 19:06 ` Yinghai Lu
2011-03-02 19:13 ` Tejun Heo
2011-03-02 20:32 ` Yinghai Lu
2011-03-02 20:57 ` Tejun Heo
2011-03-02 21:14 ` Yinghai Lu
2011-03-03 6:17 ` Tejun Heo
2011-03-10 18:46 ` Yinghai Lu
2011-03-11 8:29 ` Tejun Heo
2011-03-11 8:33 ` Tejun Heo
2011-03-11 15:48 ` Yinghai Lu
2011-03-11 15:54 ` Tejun Heo
2011-03-11 18:02 ` Yinghai Lu
2011-03-11 18:19 ` Tejun Heo
2011-03-11 18:25 ` Yinghai Lu
2011-03-11 18:29 ` Tejun Heo
2011-03-11 18:45 ` Yinghai Lu
2011-03-11 9:31 ` [PATCH x86/mm] x86-64, NUMA: Don't call numa_set_distanc() for all possible node combinations during emulation Tejun Heo
2011-03-11 15:42 ` Yinghai Lu
2011-03-11 16:03 ` Tejun Heo
2011-03-11 19:05 ` Yinghai Lu
2011-03-02 10:43 ` [PATCH x86/mm] x86-64, NUMA: Fix distance table handling Ingo Molnar
2011-03-02 10:53 ` Tejun Heo
2011-03-02 10:59 ` Tejun Heo
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