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Message-ID: <6599ad830807150911jede167ewbcdfdff905b5059e@mail.gmail.com>
Date: Tue, 15 Jul 2008 09:11:10 -0700
From: "Paul Menage" <menage@google.com>
To: "Paul Jackson" <pj@sgi.com>
Subject: Re: [PATCH] cpuset: Make rebuild_sched_domains() usable from any context
Cc: "Max Krasnyansky" <maxk@qualcomm.com>, mingo@elte.hu,
       linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl
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On Tue, Jul 15, 2008 at 9:07 AM, Paul Jackson <pj@sgi.com> wrote:
> If this rebuild thread was the -only- way that sched domains were
> allowed to be rebuilt, and if this rebuild was done -asynchronously-
> sometime shortly after requested, without any error or status feedback,
> then it would seem to simplify the locking issues.

I sent a patch that was similar a couple of weeks ago, that used a
workqueue to do the rebuild. It didn't quite work then since it wasn't
safe to call get_online_cpus() from a multi-threaded workqueue then,
but I believe there's been a patch since then that makes this safe.
And if not, we could always have a single-threaded workqueue that
wasn't bound to any particular CPU.

Paul
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