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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] qemu vl.c
Date: Sun, 16 Dec 2007 14:30:34 +0000
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To: qemu-devel@nongnu.org

On Sunday 16 December 2007, Andrzej Zaborowski wrote:
> CVSROOT:	/sources/qemu
> Module name:	qemu
> Changes by:	Andrzej Zaborowski <balrog>	07/12/16 13:17:13
>
> Modified files:
> 	.              : vl.c
>
> Log message:
> 	Redundant timer rearm optimisation by Anders Melchiorsen.

I think this is incorrect.

When a timer is modified, we need to rearm the host timer immediately. We can 
not wait for the old timer to fire, or for execution to fall back to the 
main_loop_wait.  Consider the case where the guest adds a timer interrupt and 
immediately enters a tight loop - Quite a common operation when calibrating a 
software delay loop. The timer won't be rearmed until some other event 
occurs. It the system is otherwise quiescent and you're not using SDL output 
it may never occur.

Paul