From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:46640)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1VssZM-0006yc-VD
	for qemu-devel@nongnu.org; Tue, 17 Dec 2013 06:12:14 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1VssZH-00087J-L6
	for qemu-devel@nongnu.org; Tue, 17 Dec 2013 06:12:08 -0500
Received: from mail-ee0-x22d.google.com ([2a00:1450:4013:c00::22d]:43398)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <paolo.bonzini@gmail.com>) id 1VssZH-000878-Cq
	for qemu-devel@nongnu.org; Tue, 17 Dec 2013 06:12:03 -0500
Received: by mail-ee0-f45.google.com with SMTP id d49so2791715eek.32
	for <qemu-devel@nongnu.org>; Tue, 17 Dec 2013 03:12:02 -0800 (PST)
Sender: Paolo Bonzini <paolo.bonzini@gmail.com>
Message-ID: <52B0317E.90907@redhat.com>
Date: Tue, 17 Dec 2013 12:11:58 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
MIME-Version: 1.0
References: <1386933277-20003-1-git-send-email-a.motakis@virtualopensystems.com>
	<1386933277-20003-2-git-send-email-a.motakis@virtualopensystems.com>
	<52ABD64C.6060507@redhat.com>
	<CAG8rG2wunjr6WUKudDGwFcSUR-tzijsagvc_hQzTLLNiLtBEaQ@mail.gmail.com>
	<20131216164725.7ed7cae1@nial.usersys.redhat.com>
In-Reply-To: <20131216164725.7ed7cae1@nial.usersys.redhat.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH v3 1/7] Add -mem-share option
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Igor Mammedov <imammedo@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, snabb-devel@googlegroups.com, Stefan Hajnoczi <stefanha@redhat.com>, Juan Quintela <quintela@redhat.com>, Jan Kiszka <jan.kiszka@siemens.com>, Michael Tokarev <mjt@tls.msk.ru>, qemu-devel qemu-devel <qemu-devel@nongnu.org>, Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>, Markus Armbruster <armbru@redhat.com>, Orit Wasserman <owasserm@redhat.com>, Anthony Liguori <aliguori@amazon.com>, Luke Gorrie <lukego@gmail.com>, Antonios Motakis <a.motakis@virtualopensystems.com>, VirtualOpenSystems Technical Team <tech@virtualopensystems.com>, =?ISO-8859-1?Q?Andreas_F=E4rber?= <afaerber@suse.de>, Richard Henderson <rth@twiddle.net>

Il 16/12/2013 16:47, Igor Mammedov ha scritto:
> memdev is introduced here: http://lists.gnu.org/archive/html/qemu-devel/2013-11/msg02532.html
> 
> as for mem-path & mem-prealloc, I was thinking about adding HugePageMem backend
> to handle hugepage specifics. mem-share could be a part of ShareMem backend
> or something like this.

We need three backends, something like the following:

- anonymous mmap (-object memory-ram,size=128M)

- file mmap (-object memory-file,shared=on/off,size=128M,file=FILENAME),
creates file if size property provided.

- mkstemp + file mmap (-object memory-hugepage,size=128M,path=PATH)

I don't think shared=on/off is useful in the third case, but it would be
trivial to add.

Paolo