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From: "Màrius Montón" <marius.monton@uab.cat>
To: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] time inside qemu
Date: Fri, 29 Dec 2006 18:53:37 +0100	[thread overview]
Message-ID: <45955621.2030301@uab.cat> (raw)
In-Reply-To: <200612291743.05983.paul@codesourcery.com>


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Hi,

As I understand, OSes running inside qemu "have" notion of time: (its
date and time works, time(1) command works, etc.).
My question is about how qemu manages time. I need to stop and start
again this "virtual-time".

I just tried with cpu_disable_ticks() and cpu_enable_ticks(). It seems
to work partially: at least now system date and time are out of sync..

Màrius

Paul Brook wrote:
> On Friday 29 December 2006 16:22, Màrius Montón wrote:
>   
>> Hi,
>>
>> For my work on QEMU-SC, I need to stop time inside qemu.
>> I need it in order to simulate HW modules with SystemC simulator, and
>> meanwhile stop qemu time.
>> In this way, applications running on qem should see its time freeze, and
>> measurements of total time spent by application + specific HW be more
>> realistic (now, total time is the sum of SW + HW simulation )
>>     
>
> qemu is not cycle accurate or even deterministic.
>
> Fabrice was working on some code to make it deterministic, but he never posted 
> the code.
>
> Paul
>
>   

-- 
Màrius Montón i Macián   marius.monton@uab.cat
<mailto:marius.monton@uab.cat>  http://cephis.uab.es
<http://www.mariusmonton.name>
Hardware Engineer
CEPHIS
Centre de Prototips i Solucions Hardware-Software
Dep. Microelectrònica i Sistemes Electrònics
ETSE - Universitat Autònoma de Barcelona (UAB) 	Phone: +34 935 813 534
Fax: +34 935 813 033
QC-2090D. ETSE. Campus UAB.
080193 Bellaterra



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  reply	other threads:[~2006-12-29 17:50 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-12-29 16:22 [Qemu-devel] time inside qemu Màrius Montón
2006-12-29 17:43 ` Paul Brook
2006-12-29 17:53   ` Màrius Montón [this message]
2006-12-29 18:10     ` Paul Brook
2007-04-16 14:41       ` Marius Monton
2007-04-16 15:12         ` Paul Brook
2007-04-17 14:05           ` Marius Monton
2007-04-17 14:22             ` Paul Brook
2007-04-16 21:59     ` Eduardo Felipe
2006-12-31 14:52   ` Markus Schiltknecht
  -- strict thread matches above, loose matches on Subject: below --
2006-12-29 11:13 Màrius Montón

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