From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=57095 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PhMLI-0000RP-B5 for qemu-devel@nongnu.org; Mon, 24 Jan 2011 08:20:27 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PhMLD-0001NZ-7E for qemu-devel@nongnu.org; Mon, 24 Jan 2011 08:20:24 -0500 Received: from mail-ww0-f53.google.com ([74.125.82.53]:61170) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PhMLD-0001NK-0L for qemu-devel@nongnu.org; Mon, 24 Jan 2011 08:20:19 -0500 Received: by wwi18 with SMTP id 18so3977491wwi.10 for ; Mon, 24 Jan 2011 05:20:18 -0800 (PST) Message-ID: <4D3D7C8D.2070209@gmail.com> Date: Mon, 24 Jan 2011 14:20:13 +0100 From: Stefano Bonifazi MIME-Version: 1.0 References: <000001cbb58c$221f5a00$011aa8c0@side35ya3cah0n> <4D330D01.9060801@gmail.com> <4D33203B.6080505@gmail.com> <4D3340AB.60001@gmail.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: TCG flow vs dyngen List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: =?UTF-8?B?UmFwaGHDq2wgTGVmw6h2cmU=?= , qemu-devel@nongnu.org On 01/16/2011 08:24 PM, Peter Maydell wrote: > 2011/1/16 Stefano Bonifazi: >> I need to make the different instances of qemu-user exchange data .. >> obviously keeping all of them in the same address space would be the easiest >> way (unless I have to change all qemu code ;) ) > > The problem is that you're trying to break a fundamental > assumption made by a lot of qemu code. That's a large > job which involves understanding, checking and possibly > changing lots of already written code. In contrast, the > code you need to exchange data between the instances is > going to be fairly small and self contained and you'll already > understand it because you've written it/will write it. I think > it's pretty clear which one is going to be easier. > >>> Running each qemu as its own >>> process and using interprocess communication for whatever >>> coordination you need between the various instances seems >>> more likely to be workable to me. > >> Exactly, it was the easiest way also for me.. and I've already done it, >> works smoothly .. the only big problem is that it is not good for my >> teacher.. he says it should work the dynamic library way o.O > > I think he's wrong. (You might like to think about what happens > if the program being emulated in qemu user-mode does a fork()). > > Basically you're trying to do things the hard way; maybe > you can get something that sort of works in the subset of > cases you care about, but why on earth put in that much > time and effort on something irrelevant to the actual problem > you're trying to work on? > > -- PMM > > Well my teacher's answer was that it is useless doing that, as there are already plenty of solutions based on IPC .. they are interested in this other approach, testing it .. They are not interested on how difficult it can be for a student, how long it can take.. :( Best regards, Stefano B.