Re: [PATCH 58/76] idle, x86: Allow off-lined CPU to enter deeperC states

From: Boris Ostrovsky
Date: Mon Apr 02 2012 - 14:11:01 EST


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

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