From: Andi Kleen <ak@suse.de>
Organization: SUSE Linux Products GmbH, Nuernberg, GF: Markus Rex, HRB 16746 (AG Nuernberg)
To: "Aaron Durbin" <adurbin@google.com>
Subject: Re: [PATCH] x86_64: Avoid NMI Watchdog and/or long wait in setup_APIC_timer
Date: Thu, 9 Aug 2007 02:50:43 +0200
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> 
> I was thinking along the same lines as well, but I really didn't know how
> important all that code was for waiting for the next irq slice. I'm not time
> expert, but I would imagine we would resynchronize correctly in the future after
> this code path?

The idea is to just have the apic timers roughly at the same times + some fixed
offset as the main timer.  Otherwise e.g. add_timer could jitter up to a jiffie
regarding the jiffies counter. But long term drift will destroy the synchronization 
anyways.

I guess i'll send it in anyways for .23; it would be too risky to change anything 
radical in this area that late. Then later it can be revisited.

-Andi 


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