[ovirt-devel] Re: device compatibility interface for live migration with assigned devices
On Thu, Aug 13, 2020 at 12:24:50PM +0800, Jason Wang wrote: > > On 2020/8/10 下午3:46, Yan Zhao wrote: > > > driver is it handled by? > > It looks that the devlink is for network device specific, and in > > devlink.h, it says > > include/uapi/linux/devlink.h - Network physical device Netlink > > interface, > > > Actually not, I think there used to have some discussion last year and the > conclusion is to remove this comment. > > It supports IB and probably vDPA in the future. > hmm... sorry, I didn't find the referred discussion. only below discussion regarding to why to add devlink. https://www.mail-archive.com/netdev@vger.kernel.org/msg95801.html >This doesn't seem to be too much related to networking? Why can't something >like this be in sysfs? It is related to networking quite bit. There has been couple of iteration of this, including sysfs and configfs implementations. There has been a consensus reached that this should be done by netlink. I believe netlink is really the best for this purpose. Sysfs is not a good idea https://www.mail-archive.com/netdev@vger.kernel.org/msg96102.html >there is already a way to change eth/ib via >echo 'eth' > /sys/bus/pci/drivers/mlx4_core/:02:00.0/mlx4_port1 > >sounds like this is another way to achieve the same? It is. However the current way is driver-specific, not correct. For mlx5, we need the same, it cannot be done in this way. Do devlink is the correct way to go. https://lwn.net/Articles/674867/ There a is need for some userspace API that would allow to expose things that are not directly related to any device class like net_device of ib_device, but rather chip-wide/switch-ASIC-wide stuff. Use cases: 1) get/set of port type (Ethernet/InfiniBand) 2) monitoring of hardware messages to and from chip 3) setting up port splitters - split port into multiple ones and squash again, enables usage of splitter cable 4) setting up shared buffers - shared among multiple ports within one chip we actually can also retrieve the same information through sysfs, .e.g |- [path to device] |--- migration | |--- self | | |---device_api | | |---mdev_type | | |---software_version | | |---device_id | | |---aggregator | |--- compatible | | |---device_api | | |---mdev_type | | |---software_version | | |---device_id | | |---aggregator > > > I feel like it's not very appropriate for a GPU driver to use > > this interface. Is that right? > > > I think not though most of the users are switch or ethernet devices. It > doesn't prevent you from inventing new abstractions. so need to patch devlink core and the userspace devlink tool? e.g. devlink migration > Note that devlink is based on netlink, netlink has been widely used by > various subsystems other than networking. the advantage of netlink I see is that it can monitor device status and notify upper layer that migration database needs to get updated. But not sure whether openstack would like to use this capability. As Sean said, it's heavy for openstack. it's heavy for vendor driver as well :) And devlink monitor now listens the notification and dumps the state changes. If we want to use it, need to let it forward the notification and dumped info to openstack, right? Thanks Yan ___ Devel mailing list -- devel@ovirt.org To unsubscribe send an email to devel-le...@ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/devel@ovirt.org/message/6LMZGVXJ4KMYJTPZFHI5KR64YJIROQPJ/
[ovirt-devel] ovirt-engine 4.4.2 has been branched
I've now branched oVirt 4.4.2, this will allow us to start working on 4.4.3 bugs/features and also maintain the stability of 4.4.2 before the final build. How does it affect you: If you are working on 4.4.3 content you can now submit your work to master and it will be included in 4.4.3 If you are working on 4.4.2 content you will have to push it to master first and then backport it to the ovirt-engine-4.4.2.z branch ___ Devel mailing list -- devel@ovirt.org To unsubscribe send an email to devel-le...@ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/devel@ovirt.org/message/SKE6MIXY47JFFJBRDO6YBJ62JILDVJ7W/
[ovirt-devel] Re: device compatibility interface for live migration with assigned devices
On Fri, 7 Aug 2020 13:59:42 +0200 Cornelia Huck wrote: > On Wed, 05 Aug 2020 12:35:01 +0100 > Sean Mooney wrote: > > > On Wed, 2020-08-05 at 12:53 +0200, Jiri Pirko wrote: > > > Wed, Aug 05, 2020 at 11:33:38AM CEST, yan.y.z...@intel.com wrote: > > (...) > > > > >software_version: device driver's version. > > > > in .[.bugfix] scheme, where there is no > > > >compatibility across major versions, minor versions have > > > >forward compatibility (ex. 1-> 2 is ok, 2 -> 1 is not) > > > > and > > > >bugfix version number indicates some degree of internal > > > >improvement that is not visible to the user in terms of > > > >features or compatibility, > > > > > > > > vendor specific attributes: each vendor may define different attributes > > > > device id : device id of a physical devices or mdev's parent pci > > > > device. > > > > it could be equal to pci id for pci devices > > > > aggregator: used together with mdev_type. e.g. aggregator=2 together > > > > with i915-GVTg_V5_4 means 2*1/4=1/2 of a gen9 Intel > > > >graphics device. > > > > remote_url: for a local NVMe VF, it may be configured with a remote > > > > url of a remote storage and all data is stored in the > > > >remote side specified by the remote url. > > > > ... > > just a minor not that i find ^ much more simmple to understand then > > the current proposal with self and compatiable. > > if i have well defiend attibute that i can parse and understand that allow > > me to calulate the what is and is not compatible that is likely going to > > more useful as you wont have to keep maintianing a list of other compatible > > devices every time a new sku is released. > > > > in anycase thank for actully shareing ^ as it make it simpler to reson > > about what > > you have previously proposed. > > So, what would be the most helpful format? A 'software_version' field > that follows the conventions outlined above, and other (possibly > optional) fields that have to match? Just to get a different perspective, I've been trying to come up with what would be useful for a very different kind of device, namely vfio-ccw. (Adding Eric to cc: for that.) software_version makes sense for everybody, so it should be a standard attribute. For the vfio-ccw type, we have only one vendor driver (vfio-ccw_IO). Given a subchannel A, we want to make sure that subchannel B has a reasonable chance of being compatible. I guess that means: - same subchannel type (I/O) - same chpid type (e.g. all FICON; I assume there are no 'mixed' setups -- Eric?) - same number of chpids? Maybe we can live without that and just inject some machine checks, I don't know. Same chpid numbers is something we cannot guarantee, especially if we want to migrate cross-CEC (to another machine.) Other possibly interesting information is not available at the subchannel level (vfio-ccw is a subchannel driver.) So, looking at a concrete subchannel on one of my machines, it would look something like the following: software_version=1.0.0 type=vfio-ccw <-- would be vfio-pci on the example above subchannel_type=0 chpid_type=0x1a chpid_mask=0xf0<-- not sure if needed/wanted Does that make sense? ___ Devel mailing list -- devel@ovirt.org To unsubscribe send an email to devel-le...@ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/devel@ovirt.org/message/J7KALAL5OL62HTYO3FTEZSQ7MI6QXPYH/
[ovirt-devel] Re: device compatibility interface for live migration with assigned devices
On 2020/8/10 下午3:46, Yan Zhao wrote: driver is it handled by? It looks that the devlink is for network device specific, and in devlink.h, it says include/uapi/linux/devlink.h - Network physical device Netlink interface, Actually not, I think there used to have some discussion last year and the conclusion is to remove this comment. It supports IB and probably vDPA in the future. I feel like it's not very appropriate for a GPU driver to use this interface. Is that right? I think not though most of the users are switch or ethernet devices. It doesn't prevent you from inventing new abstractions. Note that devlink is based on netlink, netlink has been widely used by various subsystems other than networking. Thanks Thanks Yan ___ Devel mailing list -- devel@ovirt.org To unsubscribe send an email to devel-le...@ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/devel@ovirt.org/message/VQEWXGTMP4TWLYU6ZXACRWWRQK23HLWK/
