From: Tejun Heo <tj@kernel.org>
To: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>,
Andrew Morton <akpm@linux-foundation.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, 01 Jul 2009 08:20:38 +0900 [thread overview]
Message-ID: <4A4A9DC6.6020003@kernel.org> (raw)
In-Reply-To: <alpine.DEB.1.10.0906301809330.11362@gentwo.org>
Hello, Christoph.
Christoph Lameter wrote:
> I looked at allocating for online cpus only a couple of years back but at
> that per cpu state was kept for offlined cpus in per cpu areas. There are
> numerous assumptions in per cpu handling all over the kernel that a percpu
> area is always available.
The plan is to allocate and keep percpu areas for cpus which have ever
been up. There'll be no taking down of percpu areas. Conversion from
possible to has_ever_been_up should be much easier than possible ->
online. State keeping will work fine too.
> We successfully restricted it to only possible
> cpus. ACPI may be the worst offender there. If you can get all of that
> addressed then we can move to pure on demand allocation. Which also would
> complicate a per cpu memory allocator allocator.
I don't think it will be too complex. The necessary bits are already
there and they are necessary for other stuff too, so...
Thanks.
--
tejun
next prev parent reply other threads:[~2009-06-30 23:21 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
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 [this message]
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
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4A4A9DC6.6020003@kernel.org \
--to=tj@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=andi@firstfloor.org \
--cc=cl@linux-foundation.org \
--cc=hpa@zytor.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).