On 01/13/2014 07:32 AM, Michael Dalton wrote: > Hi Michael, > > On Sun, Jan 12, 2014 at 9:09 AM, Michael S. Tsirkin <mst@xxxxxxxxxx> wrote: >> Can't we add struct attribute * to netdevice, and pass that in when >> creating the kobj? > I like that idea, I think that will work and should be better than > the alternatives. The actual kobjs for RX queues (struct netdev_rx_queue) > are allocated and deallocated by calls to net_rx_queue_update_kobjects, > which resizes RX queue kobjects when the netdev RX queues are resized. > > Is this what you had in mind: > (1) Add a pointer to an attribute group to struct net_device, used for > per-netdev rx queue attributes and initialized before the call to > register_netdevice(). > (2) Declare an attribute group containing the mergeable_rx_buffer_size > attribute in virtio-net, and initialize the per-netdevice group pointer > to the address of this group in virtnet_probe before register_netdevice > (3) In net-sysfs, modify net_rx_queue_update_kobjects > (or rx_queue_add_kobject) to call sysfs_create_group on the > per-netdev attribute group (if non-NULL), adding the attributes in > the group to the RX queue kobject. > > That should allow us to have per-RX queue attributes that are > device-specific. I'm not a sysfs expert, but it seems that rx_queue_ktype > and rx_queue_sysfs_ops presume that all rx queue sysfs operations are > performed on attributes of type rx_queue_attribute. That type will need > to be moved from net-sysfs.c to a header file like netdevice.h so that > the type can be used in virtio-net when we declare the > mergeable_rx_buffer_size attribute. There's a possible issue, rx queue sysfs depends on CONFIG_RPS. So we probably need a dedicated attribute just for virtio-net. > > The last issue is how the rx_queue_attribute 'show' function > implementation for mergeable_rx_buffer_size will access the appropriate > per-receive queue EWMA data. The arguments to the show function will be > the netdev_rx_queue and the attribute itself. We can get to the > struct net_device from the netdev_rx_queue. If we extended > netdev_rx_queue to indicate the queue_index or to store a void *priv_data > pointer, that would be sufficient to allow us to resolve this issue. > > Please let me know if the above sounds good or if you see a better way > to accomplish this goal. Thanks! > > Best, > > Mike _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
