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Date: Tue, 14 Nov 2017 18:40:49 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Daniel Bristot de Oliveira <bristot@redhat.com>
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Subject: Re: [RFC PATCH 0/2] x86: Fix missing core serialization on migration
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On Tue, Nov 14, 2017 at 06:17:13PM +0100, Daniel Bristot de Oliveira wrote:

> IIRC, if the dest cpu is idle and the system is with idle=poll, no IPI
> is fired as well, but that is not a very common case.

You're thinking about wake from idle? That is almost always without IPI,
even without idle=poll.

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Subject: Re: [RFC PATCH 0/2] x86: Fix missing core serialization on migration
Date: Tue, 14 Nov 2017 18:40:49 +0100
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On Tue, Nov 14, 2017 at 06:17:13PM +0100, Daniel Bristot de Oliveira wrote:

> IIRC, if the dest cpu is idle and the system is with idle=poll, no IPI
> is fired as well, but that is not a very common case.

You're thinking about wake from idle? That is almost always without IPI,
even without idle=poll.