From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: tmem docs Date: Tue, 28 May 2013 12:40:58 -0400 Message-ID: <20130528164058.GB6073@phenom.dumpdata.com> References: <6035A0D088A63A46850C3988ED045A4B5C1E450B@BITCOM1.int.sbss.com.au> <20130527111444.GN11427@reaktio.net> <6035A0D088A63A46850C3988ED045A4B5C1E6591@BITCOM1.int.sbss.com.au> <20130528144910.GQ724@phenom.dumpdata.com> <27835fe7-1d80-4aea-8bca-4cb38dc42490@default> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <27835fe7-1d80-4aea-8bca-4cb38dc42490@default> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Dan Magenheimer Cc: James Harper , xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On Tue, May 28, 2013 at 09:20:28AM -0700, Dan Magenheimer wrote: > > From: Konrad Rzeszutek Wilk > > Subject: Re: [Xen-devel] tmem docs > > > > On Tue, May 28, 2013 at 12:26:15AM +0000, James Harper wrote: > > > > On Mon, May 27, 2013 at 09:14:09AM +0000, James Harper wrote: > > > > > Where is the best place to read about tmem hypercall abi? Should I start > > > > > with the Linux implementation? > > > > > > > > I'm not really answering your question here.. but if you didn't see these links, > > > > take a look, they might help: > > > > http://lists.xen.org/archives/html/xen-devel/2013-05/msg01892.html > > > > > > That all tells me about how great tmem is, and some of the interfaces exposed by Linux, but I can't > > find anything about the interfaces exposed by Xen that Windows would need to use. It seems that the > > interface is fairly thin though, and I have a few Windows related problems to solve first before I can > > even think about making use of tmem. > > > > Let's CC Dan here. He has a stash of documents on that. > > > > But looking at the include/public/tmem.h it is very slim on comments. The ones > > that are of interest to you (I think) are: > > > > TMEM_DESTROY_POOL, TMEM_NEW_POOL, TMEM_PUT_PAGE, and TMEM_GET_PAGE. > > > > > Thanks > > > James > > Hi James -- > > I'll be working for a few more weeks and would be happy > to answer any questions I can. However, I am no longer on the > xen-devel email list so you will need to cc me directly. > > I'm gathering you are trying to connect a Windows kernel to the > Xen tmem ABI? There have been various ideas proposed about > connecting up Linux _userland_ apps to tmem and it may be possible > to do that for Windows as well. However, the existing ABI > is probably best suited for a guest kernel, and I've never > had access to Windows kernel source so I'm not in a position > to judge how easy or how hard it would be to modify Windows > kernel source to adapt it. KY Srinivasan is currently working > on cross-guest memory capacity optimization for Linux on HyperV > and has expressed some interest in tmem for Windows so you > may want to contact him to see if he's given it any thought. > (kys@microsoft.com) KY was an early Xen contributor also. > > The tmem ABI spec is here: > > https://oss.oracle.com/projects/tmem/dist/documentation/api/tmemspec-v001.pdf Awesome. > > As you can see by the date, that spec version is very old (2008) > but, on quick scan, it is still 99% accurate. The main difference > I see is that (page 2, line 18) object identifiers are now > 192-bit instead of 64-bit. See reason for that change here: > http://lists.xen.org/archives/html/xen-devel/2010-09/msg00069.html > Is there a source for the spec so I can modify it (And also put the spec in the Xen codebase).