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To: Alan Stern <stern@rowland.harvard.edu>
Cc: sekharan@us.ibm.com, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] The idle notifier chain should be atomic
References: <20060223110350.49c8b869.akpm@osdl.org>
	<Pine.LNX.4.44L0.0602231631560.7782-100000@iolanthe.rowland.org>
From: Andi Kleen <ak@suse.de>
Date: 24 Feb 2006 00:49:32 +0100
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Alan Stern <stern@rowland.harvard.edu> writes:

> This patch (as658) makes the idle_notifier in x86_64 and idle_chain in
> s390 into atomic notifier chains rather than blocking chains.  This is
> necessary because they are called during IRQ handling as CPUs leave and
> enter the idle state.

Actually they aren't. While the code is called from the interrupt
handler logically it belong to the idle thread, not the interrupt handler.
They are only called when the interrupt directly interrupts the idle 
thread, so no atomicity needed.

-Andi

P.S.: Please cc maintainers in the future.