On Tue, Dec 22, 2015 at 01:38:29AM -0800, Rich Lane wrote: > On Mon, Dec 21, 2015 at 9:47 PM, Yuanhan Liu <yuanhan.liu at linux.intel.com> > wrote: > > On Mon, Dec 21, 2015 at 08:47:28PM -0800, Rich Lane wrote: > > The queue state change callback is the one new API that needs to be > > added because > > normal NICs don't have this behavior. > > Again I'd ask, will vring_state_changed() be enough, when above issues > are resolved: vring_state_changed() will be invoked at new_device()/ > destroy_device(), and of course, ethtool change? > > > It would be sufficient. It is not a great API though, because it requires the > application to do the conversion from struct virtio_net to a DPDK port number, > and from a virtqueue index to a DPDK queue id and direction. Also, the current > implementation often makes this callback when the vring state has not actually > changed (enabled -> enabled and disabled -> disabled). > > If you're asking about using vring_state_changed() _instead_ of the link > status > event and rte_eth_dev_socket_id(),
No, I like the idea of link status event and rte_eth_dev_socket_id(); I was just wondering why a new API is needed. Both Tetsuya and I were thinking to leverage the link status event to represent the queue stats change (triggered by vring_state_changed()) as well, so that we don't need to introduce another eth event. However, I'd agree that it's better if we could have a new dedicate event. Thomas, here is some background for you. For vhost pmd and linux virtio-net combo, the queue can be dynamically changed by ethtool, therefore, the application wishes to have another eth event, say RTE_ETH_EVENT_QUEUE_STATE_CHANGE, so that the application can add/remove corresponding queue to the datapath when that happens. What do you think of that? > then yes, it still works. I'd only consider > that a stopgap until the real ethdev APIs are implemented. > > I'd suggest to add?RTE_ETH_EVENT_QUEUE_STATE_CHANGE rather than > create another callback registration API. > > Perhaps we could merge the basic PMD which I think is pretty solid and then > continue the API discussion with patches to it. Perhaps, but let's see how hard it could be for the new eth event discussion then. --yliu