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Date: Mon, 19 Nov 2007 03:10:05 -0800 (PST)
Message-Id: <20071119.031005.127194576.davem@davemloft.net>
To: mingo@elte.hu
Cc: linux-kernel@vger.kernel.org, jeremy@goop.org, gregkh@suse.de,
       akpm@linux-foundation.org
Subject: Re: regression from softlockup fix
From: David Miller <davem@davemloft.net>
In-Reply-To: <20071119094338.GA19271@elte.hu>
References: <20071119.012119.118043374.davem@davemloft.net>
	<20071119094338.GA19271@elte.hu>
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From: Ingo Molnar <mingo@elte.hu>
Date: Mon, 19 Nov 2007 10:43:38 +0100

> * David Miller <davem@davemloft.net> wrote:
> 
> > I suspect that what is happening is that the NOHZ period is longer 
> > than the softlockup timeout (10 seconds) and we get an interrupt 
> > before the watchdog thread gets onto the cpu.
> 
> indeed! Does the patch below do the trick?

I'm sure it works but it partly defeats the purpose of NOHZ.

I really like it that my cpus sleep completely for hours at a time
when not in use. :)

Anyways, I'll give your patch a test.