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Subject: Re: [RFC][PATCH 17/18] sched: Move the second half of ttwu() to
 the remote cpu
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: frank.rowand@am.sony.com
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Date: Thu, 03 Feb 2011 18:16:53 +0100
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On Fri, 2011-01-28 at 16:04 -0800, Frank Rowand wrote:
> 
> I haven't yet tried to twist my head around either the sched_fair or the
> sched_rt load balance paths.  But wouldn't it just be safer (especially
> given that the load balance code will be modified by somebody at some
> point in the future, and that this locking complexity does require head
> twisting) to just add the pi_lock in the load-balance paths also? 

I don't think that's needed, and I'm generally hesitant to add atomics
where not strictly needed.