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Date: Tue, 12 Oct 2010 23:28:19 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Jacob Pan <jacob.jun.pan@linux.intel.com>
cc: linux-kernel@vger.kernel.org, mingo@redhat.com, hpa@zytor.com,
        mingo@elte.hu, linux-tip-commits@vger.kernel.org
Subject: Re: [tip:irq/core] x86: Sanitize apb timer interrupt handling
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On Tue, 12 Oct 2010, Jacob Pan wrote:

> 
> >x86: Sanitize apb timer interrupt handling
> >
> >Disable the interrupt in CPU_DEAD where it belongs.
> My main concern is the performance cost. The power management code for
> Moorestown system make use of the cpu hotplug code (disable_nonboot_cpus)
> but much more frequently. The system low power states are call S0 idle
> state (s0ix).
> 
> Leaving the irq enabled at the chip and desc level between S0ix states
> might give some performance benefit. That was my original thought.
> Will it cause problems?

Errm. I merily moved it to the place where it should be. You do the
disable/enable dance already today.

Thanks,

	tglx