From mboxrd@z Thu Jan  1 00:00:00 1970
From: Boris Ostrovsky <boris.ostrovsky@amd.com>
Subject: Re: [PATCH 58/76] idle, x86: Allow off-lined CPU to enter deeper
 C states
Date: Mon, 2 Apr 2012 14:10:50 -0400
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To: Tony Luck <tony.luck@gmail.com>
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On 04/02/12 14:02, Tony Luck wrote:
>> x86 halt() causes processor to go to C1 state (which is often not the
>> deepest). But other than that it seems similar to what you are describing.
>
> OK - then Konrad's suggestion of using "safe_halt()" here rather than
> "halt()" would work for ia64.

I originally didn't want to use safe_halt() because the CPU will wake up 
on an unmasked HW interrupt unlike halt(). But I guess we are not 
supposed to get any such interrupts when we are off-lining a CPU so 
safe_halt() should be OK.

Thanks.
-boris