Currently we treat set_multiq() calls specially in netdev and dpif-netdev: every pmd thread must be stopped and set_multiq() is allowed to destroy and recreate the device.
I think we can improve this by: * Generalizing the mechanism to allow changing other parameters at runtime (such as MTU). * Involving less the above layer (dpif-netdev). The request for changes often comes from below (netdev_dpdk_set_config(), or the vhost new_device() callback). There's no need for dpif-netdev to remember the requested value, all that it needs to know is that a configuration change is requested. This series implements exactly this: a mechanism to allow a netdev provider to request configuration changes, to which dpif-netdev will respond by stopping rx/tx and calling a netdev function to appy the new configuration. The new mechanism is used in this series to replace the set_multiq() call, but the idea is to use it also at least for: * Changing the MTU at runtime * Automatically detecting the number of rx queues for a vhost-user device The first commits also clean up some code in dpif-netdev and make the ports cmap fully RCU protected. v2: * Fixed do_add_port(): we have to call netdev_reconfigure() before opening the rxqs. This prevents memory leaks, and makes sure that the datapath polls the appropriate number of queues * Fixed netdev_dpdk_vhost_set_multiq(): it must call netdev_request_reconfigure(). Since it is now equal to netdev_dpdk_set_multiq(), the two function have been merged. * Fixed netdev_dpdk_set_config(): dev->requested_n_rxq is now accessed while holding the appropriate mutex. * Fixed some outdated comments about rx queue configuration. Daniele Di Proietto (11): dpif-netdev: Proper error handling in do_add_port(). dpif-netdev: Keep count of elements in port->rxq[]. dpif-netdev: Do not keep refcount for ports. dpif-netdev: Remove useless dpif-dummy/delete-port appctl. dpif-netdev: Wait an RCU grace period before freeing ports. ofproto-dpif: Call dpif_poll_threads_set() before dpif_run() dpif-netdev: Change pmd thread configuration in dpif_netdev_run(). dpif-netdev: Document locking discipline for non_pmd_mutex. dpif-netdev: Fix reconfigure_pmd_threads(). netdev: Add reconfigure request mechanism. netdev-dpdk: Use ->reconfigure() call to change rx/tx queues. lib/dpif-netdev.c | 435 +++++++++++++++++++++++++++---------------------- lib/dpif-provider.h | 3 +- lib/netdev-bsd.c | 1 + lib/netdev-dpdk.c | 180 ++++++++++---------- lib/netdev-dummy.c | 1 + lib/netdev-linux.c | 1 + lib/netdev-provider.h | 42 +++-- lib/netdev-vport.c | 1 + lib/netdev.c | 59 ++++--- lib/netdev.h | 7 +- ofproto/ofproto-dpif.c | 4 +- tests/bridge.at | 4 +- 12 files changed, 406 insertions(+), 332 deletions(-) -- 2.1.4 _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
