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From: Con Kolivas <kernel@kolivas.org>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Subject: Re: [PATCH RFC] smt nice introduces significant lock contention
Date: Fri, 2 Jun 2006 16:08:33 +1000
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Cc: linux-kernel@vger.kernel.org, "Chen, Kenneth W" <kenneth.w.chen@intel.com>,
       "'Chris Mason'" <mason@suse.com>, Ingo Molnar <mingo@elte.hu>
References: <000101c685d7$1bc84390$d234030a@amr.corp.intel.com> <200606021355.23671.kernel@kolivas.org> <447FBC28.8030401@yahoo.com.au>
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On Friday 02 June 2006 14:18, Nick Piggin wrote:
> Con Kolivas wrote:
> > On Friday 02 June 2006 12:28, Con Kolivas wrote:
> >>Actually looking even further, we only introduced the extra lookup of the
> >>next task when we started unlocking the runqueue in schedule(). Since we
> >>can get by without locking this_rq in schedule with this approach we can
> >>simplify dependent_sleeper even further by doing the dependent sleeper
> >>check after we have discovered what next is in schedule and avoid looking
> >>it up twice. I'll hack something up to do that soon.
> >
> > Something like this (sorry I couldn't help but keep hacking on it).
>
> Looking pretty good.

Thanks

> Nice to acknowledge Chris's idea for 
> trylocks in your changelog when you submit a final patch.

I absolutely would and I would ask for him to sign off on it as well, once we 
agreed on a final form.

-- 
-ck