From: Ingo Molnar <mingo@elte.hu>
To: Christoph Lameter <cl@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
tj@kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org,
linux-arch@vger.kernel.org, andi@firstfloor.org, hpa@zytor.com,
tglx@linutronix.de
Subject: Re: [PATCHSET] percpu: generalize first chunk allocators and improve lpage NUMA support
Date: Wed, 1 Jul 2009 01:07:43 +0200 [thread overview]
Message-ID: <20090630230743.GA17968@elte.hu> (raw)
In-Reply-To: <alpine.DEB.1.10.0906301847260.19482@gentwo.org>
* Christoph Lameter <cl@linux-foundation.org> wrote:
> On Wed, 1 Jul 2009, Ingo Molnar wrote:
>
> > The usecase i'm talking about is to boot a generic,
> > many-CPUs-capable kernel in a guest image.
>
> The many-cpu-capable kernel is not the issue. The number of
> potential cpus is config information provided by the hardware. In
> your case the host system provides the number of possible
> processors.
Say it says "256 CPUs".
But i only run a 2 CPU guest system. But i want to run it with the
_on demand capability_ to scale up to 256 virtual CPUs if needed,
without having to reboot the guest and without having to allocate
all the percpu space for 256 CPUs beforehand. Ok?
It is a simple, basic OS feature and concept.
Ingo
next prev parent reply other threads:[~2009-06-30 23:07 UTC|newest]
Thread overview: 66+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-06-24 13:30 [PATCHSET] percpu: generalize first chunk allocators and improve lpage NUMA support Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 01/10] x86: make pcpu_chunk_addr_search() matching stricter Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 02/10] percpu: drop @unit_size from embed first chunk allocator Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 03/10] x86,percpu: generalize 4k " Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 04/10] percpu: make 4k first chunk allocator map memory Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 05/10] x86,percpu: generalize lpage first chunk allocator Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 06/10] percpu: simplify pcpu_setup_first_chunk() Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 07/10] percpu: reorder a few functions in mm/percpu.c Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 08/10] percpu: drop pcpu_chunk->page[] Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 09/10] percpu: allow non-linear / sparse cpu -> unit mapping Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 13:30 ` [PATCH 10/10] percpu: teach large page allocator about NUMA Tejun Heo
2009-06-24 13:30 ` Tejun Heo
2009-06-24 23:55 ` [PATCHSET] percpu: generalize first chunk allocators and improve lpage NUMA support Andrew Morton
2009-06-25 0:02 ` Andi Kleen
2009-06-25 0:13 ` H. Peter Anvin
2009-06-25 9:19 ` Andi Kleen
2009-06-25 14:18 ` H. Peter Anvin
2009-06-25 19:54 ` Andi Kleen
2009-06-25 20:15 ` H. Peter Anvin
2009-06-25 20:26 ` Andi Kleen
2009-06-26 0:40 ` Tejun Heo
2009-06-26 2:02 ` H. Peter Anvin
2009-06-26 6:54 ` Andi Kleen
2009-06-25 2:35 ` Tejun Heo
2009-06-25 9:20 ` Ingo Molnar
2009-06-29 23:20 ` Christoph Lameter
2009-06-29 23:39 ` Andrew Morton
2009-06-30 14:24 ` Christoph Lameter
2009-06-30 19:15 ` Ingo Molnar
2009-06-30 19:39 ` Christoph Lameter
2009-06-30 20:21 ` Scott Lurndal
2009-06-30 21:31 ` Ingo Molnar
2009-06-30 22:16 ` Christoph Lameter
2009-06-30 22:31 ` Ingo Molnar
2009-06-30 22:40 ` Andi Kleen
2009-07-01 0:48 ` Tejun Heo
2009-06-30 22:55 ` Christoph Lameter
2009-06-30 22:55 ` Christoph Lameter
2009-06-30 23:07 ` Ingo Molnar [this message]
2009-06-30 23:18 ` Christoph Lameter
2009-06-30 23:30 ` Ingo Molnar
2009-07-01 6:34 ` Andi Kleen
2009-06-30 23:20 ` Tejun Heo
2009-06-30 23:31 ` Ingo Molnar
2009-06-30 23:34 ` H. Peter Anvin
2009-07-01 6:42 ` Andi Kleen
2009-07-01 10:21 ` Tejun Heo
2009-07-01 12:23 ` Andi Kleen
2009-07-01 12:53 ` Tejun Heo
2009-07-01 13:11 ` Andi Kleen
2009-07-01 17:33 ` Christoph Lameter
2009-07-01 22:42 ` Tejun Heo
2009-07-03 23:14 ` Tejun Heo
2009-07-03 23:14 ` Tejun Heo
2009-07-13 10:12 ` [PATCH 04/10] percpu: make 4k first chunk allocator map memory David Howells
2009-07-15 3:17 ` Tejun Heo
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