Can we Access the root filesystem from Xen Hypervisor Code. e.g creating dir at /proc Any pointers will be useful. thanks -tej _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
George Dunlap
2008-Nov-14 14:58 UTC
Re: [Xen-devel] Root filesystem access from Xen Hypervisor
If you want to export data out of the hypervisor, the easiest thing to do is set up a shared memory mechanism. Look at xen/common/trace.c and tools/xentrace/xentrace.c for one simple xen-to-userspace example. Hmm... if you want to reuse as much of the interface as possible, you''ll probably need to make a Linux kernel module that implements /proc/gcov-xen. The hypervisor can write usage data to the shared page(s), and the kernel module can read it, interpret it, and make the /proc files based on it. For a sample of how to use xen-to-kernel shared memory, you can look at xenoprofile; but be warned that it''s suffering some bitrot. Let me know how you fare -- it seems like an interesting project. -George On Fri, Nov 14, 2008 at 12:15 PM, Tej <bewith.tej@gmail.com> wrote:> On 11/14/08, George Dunlap <dunlapg@umich.edu> wrote: >> /proc is owned by the Linux Kernel; Xen has no filesystem code in it. >> >> What is it you''re trying to do? > > i am trying to port the gcov for XEN HYpervisor. I could able to > create profiling info but i could not able to populate filesystem for > profiling purpose. > > >> >> -George >> >> On Fri, Nov 14, 2008 at 11:45 AM, Tej <bewith.tej@gmail.com> wrote: >>> Can we Access the root filesystem from Xen Hypervisor Code. >>> e.g creating dir at /proc >>> >>> >>> Any pointers will be useful. >>> >>> >>> thanks >>> -tej >>> >>> _______________________________________________ >>> 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 11/14/08, George Dunlap <George.Dunlap@eu.citrix.com> wrote:> If you want to export data out of the hypervisor, the easiest thing to > do is set up a shared memory mechanism. Look at xen/common/trace.c > and tools/xentrace/xentrace.c for one simple xen-to-userspace example. > > Hmm... if you want to reuse as much of the interface as possible, > you''ll probably need to make a Linux kernel module that implements > /proc/gcov-xen. The hypervisor can write usage data to the shared > page(s), and the kernel module can read it, interpret it, and make the > /proc files based on it.i am also thinking on same line.> > For a sample of how to use xen-to-kernel shared memory, you can look > at xenoprofile; but be warned that it''s suffering some bitrot.thanks for nice pointers> > Let me know how you fare -- it seems like an interesting project.sure> > -Georgethanks -tej> > On Fri, Nov 14, 2008 at 12:15 PM, Tej <bewith.tej@gmail.com> wrote: >> On 11/14/08, George Dunlap <dunlapg@umich.edu> wrote: >>> /proc is owned by the Linux Kernel; Xen has no filesystem code in it. >>> >>> What is it you''re trying to do? >> >> i am trying to port the gcov for XEN HYpervisor. I could able to >> create profiling info but i could not able to populate filesystem for >> profiling purpose. >> >> >>> >>> -George >>> >>> On Fri, Nov 14, 2008 at 11:45 AM, Tej <bewith.tej@gmail.com> wrote: >>>> Can we Access the root filesystem from Xen Hypervisor Code. >>>> e.g creating dir at /proc >>>> >>>> >>>> Any pointers will be useful. >>>> >>>> >>>> thanks >>>> -tej >>>> >>>> _______________________________________________ >>>> 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
Mark Williamson
2008-Nov-15 01:16 UTC
[Xen-devel] Re: Root filesystem access from Xen Hypervisor
What exactly are you trying to accomplish? Do you want to access the root filesystem of a domU, or ...? What sequence of commands would you like to work? ;-) Cheers, Mark On Friday 14 November 2008 11:45:32 Tej wrote:> Can we Access the root filesystem from Xen Hypervisor Code. > e.g creating dir at /proc > > > Any pointers will be useful. > > > thanks > -tej_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel