From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1L8fwa-0007gY-AD
	for qemu-devel@nongnu.org; Fri, 05 Dec 2008 14:02:28 -0500
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1L8fwZ-0007g8-K8
	for qemu-devel@nongnu.org; Fri, 05 Dec 2008 14:02:27 -0500
Received: from [199.232.76.173] (port=50383 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1L8fwZ-0007g3-F6
	for qemu-devel@nongnu.org; Fri, 05 Dec 2008 14:02:27 -0500
Received: from mx2.redhat.com ([66.187.237.31]:38669)
	by monty-python.gnu.org with esmtp (Exim 4.60)
	(envelope-from <avi@redhat.com>) id 1L8fwY-0003eR-Gh
	for qemu-devel@nongnu.org; Fri, 05 Dec 2008 14:02:27 -0500
Message-ID: <49397AC6.9070201@redhat.com>
Date: Fri, 05 Dec 2008 21:02:30 +0200
From: Avi Kivity <avi@redhat.com>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] Modular qemu?
References: <3056442136ca43729c6a2aec02c038aa.squirrel@www.boonen.name>
	<49393B8D.40209@codemonkey.ws> <493970B9.3060807@redhat.com>
	<20081205185420.GA26481@networkno.de>
In-Reply-To: <20081205185420.GA26481@networkno.de>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Reply-To: qemu-devel@nongnu.org
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Thiemo Seufer <ths@networkno.de>
Cc: qemu-devel@nongnu.org

Thiemo Seufer wrote:
>> What about non-plugin dlopen()?  Right now building qemu (with all  
>> options enabled) requires a large amount of libraries, hence a lot of  
>> dependencies.  For example, a server setup that will only be used with  
>> -vnc needs to have SDL installed.  This will only get worse with opengl  
>> support.
>>
>> I'm thinking of something similar to linux kernel modules: no backward  
>> compatible ABI, simply load-on-demand functionality that can be packaged  
>> separately to reduce dependencies.  With kvm integrated, we could even  
>> make the cpu emulator an optional loadable module.
>>     
>
> What problem would this solve?
>
>   

You build qemu once, but with separate sub-packages:

  qemu
  qemu-sdl
  qemu-vnc
  qemu-tcg
  qemu-kvm

On a desktop deployment, you install qemu, qemu-kvm, qemu-tcg, and 
qemu-sdl (which pulls a bunch of dependencies).  On a server deployment, 
you install qemu, qemu-vnc, and qemu-kvm (which avoids dependencies and 
the tcg code which is not useful on a server).  This allows a 
distribution to only maintain and support one qemu binary for different 
deployment scenarios.

We might even make the various targets loadable modules, so you have a 
single binary which supports a bunch of targets.  This is more difficult 
due to the large numbers of #defines, but is doable.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.