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Message-ID: <4421307F.8020300@yahoo.com.au>
Date: Wed, 22 Mar 2006 22:09:51 +1100
From: Nick Piggin <nickpiggin@yahoo.com.au>
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To: Anton Blanchard <anton@samba.org>
CC: linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, mingo@elte.hu,
       akpm@osdl.org
Subject: Re: [PATCH] possible scheduler deadlock in 2.6.16
References: <20060322104143.GC30422@krispykreme>
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Anton Blanchard wrote:

> One way to solve this is to always take runqueues in cpu id order. To do
> this we add a cpu variable to the runqueue and check it in the
> double runqueue locking functions.
> 
> Thoughts?
> 

You're right. I can't think of a better fix, although we've been trying
to avoid adding cpu to the runqueue structure.

I was going to suggest moving more work into wake_sleeping_dependent
instead, but cores with 4 and more threads now make that less desirable
I suppose.

-- 
SUSE Labs, Novell Inc.
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