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From: Rusty Russell <rusty@rustcorp.com.au>
To: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 2/2] cpuhotplug: introduce try_get_online_cpus()
Date: Mon, 1 Jun 2009 17:01:50 +0930
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Cc: Lai Jiangshan <laijs@cn.fujitsu.com>, mingo@elte.hu,
       paulmck@linux.vnet.ibm.com, linux-kernel@vger.kernel.org,
       Oleg Nesterov <oleg@redhat.com>,
       Linus Torvalds <torvalds@linux-foundation.org>
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On Sat, 30 May 2009 06:01:18 am Andrew Morton wrote:
> I do think that we should look at
> alternative (non-trylocky) ways of fixing them.

Speculating: we could add a "keep_cpu()" (FIXME: improve name) which is kind 
of like get_cpu() only doesn't disable preemption and only stops *this* cpu 
from going down.

Not sure where that gets us, but if someone's going to dig deep into this it 
might help.

Thanks,
Rusty.