Message-ID: <4B5C0266.1040406@kernel.org>
Date: Sun, 24 Jan 2010 17:18:46 +0900
From: Tejun Heo <tj@kernel.org>
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To: Peter Zijlstra <peterz@infradead.org>
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       Mike Galbraith <efault@gmx.de>
Subject: Re: [PATCH 04/40] sched: implement __set_cpus_allowed()
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Hello,

On 01/20/2010 05:35 PM, Tejun Heo wrote:
> Wouldn't it make more sense to share the backend implementation
> between kthread_bind() and set_cpus_allowed_ptr() instead of making
> kthread_bind() a special case?  The goals of the two functions are
> basically identical.  Why have two separate implementations?
> kthread_bind() implementation as it currently stands is pretty fragile
> too.  Making kthread_bind() backed by set_cpus_allowed_ptr() will make
> it more robust and less error-prone and all that's necessary to
> achieve that is modifying sanity checks.

I gave it shot.  The interface is cleaner this way but I couldn't
figure out where to set PF_THREAD_BOUND as actual migration may happen
in different places and p->flags can only be set while it's known the
process is not running.  At this point, I can't think of a better way
to do this than the current patch.  :-(

Thanks.

-- 
tejun
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