Hi, Is there a mechanism available in Xen such that a kernel module in dom0 can register to it and when a VM(domU) is installed or deleted or suspend or resumed kernel module in domU can send notification to its counterpart in dom0. I have looked into xenbus mechanism used by PV drivers and it won''t work for us. Inputs appreciated. Thanks -RK _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Sat, Mar 06, 2010 at 07:12:02PM -0800, ravi kerur wrote:> Hi, > > Is there a mechanism available in Xen such that a kernel module in dom0 can > register to it and when a VM(domU) is installed or deleted or suspend or > resumed kernel module in domU can send notification to its counterpart in > dom0. I have looked into xenbus mechanism used by PV drivers and it won''t > work for us. Inputs appreciated.You can listen on udev events and see when a vif device has been added. Also you can add pieces to the dom0 kernel to send uevents when a device is suspended and do something. Attached is a simple program to listen to all uevents..> > Thanks > -RK> _______________________________________________ > 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 Mon, 2010-03-08 at 16:47 +0000, Konrad Rzeszutek Wilk wrote:> On Sat, Mar 06, 2010 at 07:12:02PM -0800, ravi kerur wrote: > > Hi, > > > > Is there a mechanism available in Xen such that a kernel module in dom0 can > > register to it and when a VM(domU) is installed or deleted or suspend or > > resumed kernel module in domU can send notification to its counterpart in > > dom0. I have looked into xenbus mechanism used by PV drivers and it won''t > > work for us. Inputs appreciated. > > You can listen on udev events and see when a vif device has been added. > Also you can add pieces to the dom0 kernel to send uevents when a device > is suspended and do something. > > Attached is a simple program to listen to all uevents..Also if you are specifically interested in domain create/destruction (from the hypervisors PoV) then I think you can add a xenstore watch on "@releaseDomain" and "@introduceDomain". As far as the hypervisor is concerned things like migration or suspend/resume are just domain creation or destruction, the "illusion" of anything more is provided by the tools. If you are interested in the creation/suspension/migration/etc of domains at the toolstack level then it depends which toolstack you are targeting. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Thanks Ian and Konrad. I thought monitoring udev events or xen store watch can be done from user-level apps. I am wondering can they be used from kernel modules as well? Thanks -RK On Wed, Mar 10, 2010 at 8:09 AM, Ian Campbell <Ian.Campbell@citrix.com>wrote:> On Mon, 2010-03-08 at 16:47 +0000, Konrad Rzeszutek Wilk wrote: > > On Sat, Mar 06, 2010 at 07:12:02PM -0800, ravi kerur wrote: > > > Hi, > > > > > > Is there a mechanism available in Xen such that a kernel module in dom0 > can > > > register to it and when a VM(domU) is installed or deleted or suspend > or > > > resumed kernel module in domU can send notification to its counterpart > in > > > dom0. I have looked into xenbus mechanism used by PV drivers and it > won''t > > > work for us. Inputs appreciated. > > > > You can listen on udev events and see when a vif device has been added. > > Also you can add pieces to the dom0 kernel to send uevents when a device > > is suspended and do something. > > > > Attached is a simple program to listen to all uevents.. > > Also if you are specifically interested in domain create/destruction > (from the hypervisors PoV) then I think you can add a xenstore watch on > "@releaseDomain" and "@introduceDomain". > > As far as the hypervisor is concerned things like migration or > suspend/resume are just domain creation or destruction, the "illusion" > of anything more is provided by the tools. > > If you are interested in the creation/suspension/migration/etc of > domains at the toolstack level then it depends which toolstack you are > targeting. > > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Wed, 2010-03-10 at 23:20 +0000, ravi kerur wrote:> Thanks Ian and Konrad. I thought monitoring udev events or xen store > watch can be done from user-level apps. I am wondering can they be > used from kernel modules as well?xenstore can. I don''t think udev can. Ian.> > Thanks > -RK > > On Wed, Mar 10, 2010 at 8:09 AM, Ian Campbell > <Ian.Campbell@citrix.com> wrote: > On Mon, 2010-03-08 at 16:47 +0000, Konrad Rzeszutek Wilk > wrote: > > On Sat, Mar 06, 2010 at 07:12:02PM -0800, ravi kerur wrote: > > > Hi, > > > > > > Is there a mechanism available in Xen such that a kernel > module in dom0 can > > > register to it and when a VM(domU) is installed or deleted > or suspend or > > > resumed kernel module in domU can send notification to its > counterpart in > > > dom0. I have looked into xenbus mechanism used by PV > drivers and it won''t > > > work for us. Inputs appreciated. > > > > You can listen on udev events and see when a vif device has > been added. > > Also you can add pieces to the dom0 kernel to send uevents > when a device > > is suspended and do something. > > > > Attached is a simple program to listen to all uevents.. > > > Also if you are specifically interested in domain > create/destruction > (from the hypervisors PoV) then I think you can add a xenstore > watch on > "@releaseDomain" and "@introduceDomain". > > As far as the hypervisor is concerned things like migration or > suspend/resume are just domain creation or destruction, the > "illusion" > of anything more is provided by the tools. > > If you are interested in the creation/suspension/migration/etc > of > domains at the toolstack level then it depends which toolstack > you are > targeting. > > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Thu, Mar 11, 2010 at 07:43:00AM +0000, Ian Campbell wrote:> On Wed, 2010-03-10 at 23:20 +0000, ravi kerur wrote: > > Thanks Ian and Konrad. I thought monitoring udev events or xen store > > watch can be done from user-level apps. I am wondering can they be > > used from kernel modules as well? > > xenstore can. I don''t think udev can.<nods> Of interest might be git commit dfecff0a8934996f381cb5a80c7220ad87830ae9 "commit dfecff0a8934996f381cb5a80c7220ad87830ae9 Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Date: Thu Nov 5 15:25:40 2009 -0500 xenbus_walk - walk XenStore keys, calling callback. This is quite similar to ''pci_walk_bus.'' We walk the XenStore keys, starting at the initial path, calling the callback with each key that has a value. If the callback returns a negative value we stop, clean up, and return the value back. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> " which you could use to get more details of your XenStore values. (this commit is in Jeremy''s Xen tree git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git)> > Ian. > > > > > Thanks > > -RK > > > > On Wed, Mar 10, 2010 at 8:09 AM, Ian Campbell > > <Ian.Campbell@citrix.com> wrote: > > On Mon, 2010-03-08 at 16:47 +0000, Konrad Rzeszutek Wilk > > wrote: > > > On Sat, Mar 06, 2010 at 07:12:02PM -0800, ravi kerur wrote: > > > > Hi, > > > > > > > > Is there a mechanism available in Xen such that a kernel > > module in dom0 can > > > > register to it and when a VM(domU) is installed or deleted > > or suspend or > > > > resumed kernel module in domU can send notification to its > > counterpart in > > > > dom0. I have looked into xenbus mechanism used by PV > > drivers and it won''t > > > > work for us. Inputs appreciated. > > > > > > You can listen on udev events and see when a vif device has > > been added. > > > Also you can add pieces to the dom0 kernel to send uevents > > when a device > > > is suspended and do something. > > > > > > Attached is a simple program to listen to all uevents.. > > > > > > Also if you are specifically interested in domain > > create/destruction > > (from the hypervisors PoV) then I think you can add a xenstore > > watch on > > "@releaseDomain" and "@introduceDomain". > > > > As far as the hypervisor is concerned things like migration or > > suspend/resume are just domain creation or destruction, the > > "illusion" > > of anything more is provided by the tools. > > > > If you are interested in the creation/suspension/migration/etc > > of > > domains at the toolstack level then it depends which toolstack > > you are > > targeting. > > > > > > > > > > _______________________________________________ > 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