Hello- I am working on a project to modify Xen to precisely control the execution times of the individual guest domains, and I need some help. I considered modifying the XM python program, but it is not precise or fast enough for my application. I want to be able to pass short, simple message quickly between an application-level process and the Xen kernel asynchonously. I found an IPC mechanism designed for the method called netlink ( http://www.linuxjournal.com/article/7356), but I am not sure how to incorporate it into the Xen kernel. When I attempt to recompile the kernel with netlink, I get errors that seem to stem from type issues I am not familiar with. 2 questions: Is it possible to use a mechanism such as netlink with Xen? If so, how? Is there other functionality within Xen that could be used with minimal modification to do IPC within domain0? Any help/advice would be greatly appreciated. Thanks! --Derek _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Derek, I assume you mean "Xen Hypervisor" (as the kernel would be probably Linux dom0 kernel)? You might look at the xentrace mechanism for using a shared page to pass information out of Xen. You could probably adapt the same idea to pass information into Xen if you needed to. -George On Fri, Jul 31, 2009 at 5:39 PM, Derek Riley<derek.riley@isis.vanderbilt.edu> wrote:> Hello- > I am working on a project to modify Xen to precisely control the execution > times of the individual guest domains, and I need some help. I considered > modifying the XM python program, but it is not precise or fast enough for my > application. > > I want to be able to pass short, simple message quickly between an > application-level process and the Xen kernel asynchonously. I found an IPC > mechanism designed for the method called netlink > (http://www.linuxjournal.com/article/7356), but I am not sure how to > incorporate it into the Xen kernel. When I attempt to recompile the kernel > with netlink, I get errors that seem to stem from type issues I am not > familiar with. > > 2 questions: > Is it possible to use a mechanism such as netlink with Xen? If so, how? > Is there other functionality within Xen that could be used with minimal > modification to do IPC within domain0? > > Any help/advice would be greatly appreciated. Thanks! > --Derek > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Thu, Aug 6, 2009 at 9:01 AM, Derek Riley <derek.riley@isis.vanderbilt.edu> wrote:> Thanks for your response. I am working with the Xen Hypervisor, but I am > not familiar with xentrace. I found some information about it through > google searches, but I was unable to discover how it uses the shared page > you mentioned. Do you have any links to point me in the right direction? > Thanks > --Derek > > > On Mon, Aug 3, 2009 at 12:17 PM, George Dunlap < > George.Dunlap@eu.citrix.com> wrote: > >> Derek, >> >> I assume you mean "Xen Hypervisor" (as the kernel would be probably >> Linux dom0 kernel)? >> >> You might look at the xentrace mechanism for using a shared page to >> pass information out of Xen. You could probably adapt the same idea >> to pass information into Xen if you needed to. >> >> -George >> >> On Fri, Jul 31, 2009 at 5:39 PM, Derek >> Riley<derek.riley@isis.vanderbilt.edu> wrote: >> > Hello- >> > I am working on a project to modify Xen to precisely control the >> execution >> > times of the individual guest domains, and I need some help. I >> considered >> > modifying the XM python program, but it is not precise or fast enough >> for my >> > application. >> > >> > I want to be able to pass short, simple message quickly between an >> > application-level process and the Xen kernel asynchonously. I found an >> IPC >> > mechanism designed for the method called netlink >> > (http://www.linuxjournal.com/article/7356), but I am not sure how to >> > incorporate it into the Xen kernel. When I attempt to recompile the >> kernel >> > with netlink, I get errors that seem to stem from type issues I am not >> > familiar with. >> > >> > 2 questions: >> > Is it possible to use a mechanism such as netlink with Xen? If so, how? >> > Is there other functionality within Xen that could be used with minimal >> > modification to do IPC within domain0? >> > >> > Any help/advice would be greatly appreciated. Thanks! >> > --Derek >> > _______________________________________________ >> > Xen-devel mailing list >> > Xen-devel@lists.xensource.com >> > http://lists.xensource.com/xen-devel >> > >> > >> > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
I''m afraid the only documentation is the source code itself. Look in tools/xentrace.c, and xen/common/trace.c. The basic idea is that the page is a ring buffer with producer and consumer pointers. Xen always writes a record, then updates the producer; xentrace always reads a record, then updates the consumer. If incrementing the producer would clobber a consumer, then Xen just drops the trace record. Good luck, -George On Thu, Aug 6, 2009 at 3:04 PM, Derek Riley<derek.riley@isis.vanderbilt.edu> wrote:> > > On Thu, Aug 6, 2009 at 9:01 AM, Derek Riley > <derek.riley@isis.vanderbilt.edu> wrote: >> >> Thanks for your response. I am working with the Xen Hypervisor, but I am >> not familiar with xentrace. I found some information about it through >> google searches, but I was unable to discover how it uses the shared page >> you mentioned. Do you have any links to point me in the right direction? >> Thanks >> --Derek >> >> On Mon, Aug 3, 2009 at 12:17 PM, George Dunlap >> <George.Dunlap@eu.citrix.com> wrote: >>> >>> Derek, >>> >>> I assume you mean "Xen Hypervisor" (as the kernel would be probably >>> Linux dom0 kernel)? >>> >>> You might look at the xentrace mechanism for using a shared page to >>> pass information out of Xen. You could probably adapt the same idea >>> to pass information into Xen if you needed to. >>> >>> -George >>> >>> On Fri, Jul 31, 2009 at 5:39 PM, Derek >>> Riley<derek.riley@isis.vanderbilt.edu> wrote: >>> > Hello- >>> > I am working on a project to modify Xen to precisely control the >>> > execution >>> > times of the individual guest domains, and I need some help. I >>> > considered >>> > modifying the XM python program, but it is not precise or fast enough >>> > for my >>> > application. >>> > >>> > I want to be able to pass short, simple message quickly between an >>> > application-level process and the Xen kernel asynchonously. I found an >>> > IPC >>> > mechanism designed for the method called netlink >>> > (http://www.linuxjournal.com/article/7356), but I am not sure how to >>> > incorporate it into the Xen kernel. When I attempt to recompile the >>> > kernel >>> > with netlink, I get errors that seem to stem from type issues I am not >>> > familiar with. >>> > >>> > 2 questions: >>> > Is it possible to use a mechanism such as netlink with Xen? If so, >>> > how? >>> > Is there other functionality within Xen that could be used with minimal >>> > modification to do IPC within domain0? >>> > >>> > Any help/advice would be greatly appreciated. Thanks! >>> > --Derek >>> > _______________________________________________ >>> > Xen-devel mailing list >>> > Xen-devel@lists.xensource.com >>> > http://lists.xensource.com/xen-devel >>> > >>> > >> > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel