This list has been busy just recently, so I am wondering if my teeny patchset has been overlooked. :)
Cheers, Chris. > -----Original Message----- > From: dev-boun...@openvswitch.org [mailto:dev- > boun...@openvswitch.org] On Behalf Of Chris Luke > Sent: Wednesday, January 15, 2014 8:22 PM > To: dev@openvswitch.org > Subject: [ovs-dev] [PATCH 0/4] Adds capability to return packets back to the > kernel > > > Jesse, all, > > This patchset provides a method to return packets to the kernel for > handling as though OVS never touched them. > > To support this, we extend the datapath on kernels since 2.6.39 to be > able to pass packets back by providing a 'back_to_kernel' action which > causes the network input hook to return RX_HANDLER_PASS and userspace > packets to be re-submitted to the input queue. > > The latter, the re-submission, can happen in one of two ways: Either > with a new function in the kernel that can deliver an skb to the lower > half of __netif_receive_skb_core() (see the patch at the HEAD of > https://github.com/chrisy/linux/tree/feature/netif-receive-finish ) > or on other kernels without this function by submitting the packet to > the queue with netif_rx_ni(). > > The downside of using netif_rx_ni() is that the packet has already > traversed much of the input path and this risks duplication of action. > We mitigate this using a flag that causes some steps to be skipped, but > this is a hack (though the way we use this is cute in that the existing > implementation resets the flag for us so it seems there are no side > effects!) > > Next, we add the 'back_to_kernel' action to OpenFlow which triggers a > datapath output action using the datapath 'back_to_kernel' action. > > Suggestions for better names for 'back_to_kernel' welcome. :) > > TODO: > - When using netif_rx_ni() to send packets back from userspace, we may > be double-counting the first packet of a flow in the stats. This is > since we have no way to avoid having the packet hit the rx_handler > hook a second time and relying on it matching its flow. > - In the userspace datapath, look at whether AF_PACKET can reinsert > packets at the right place in the input path, otherwise use a tap > interface to do same. > > Signed-off-by: Chris Luke <chris_l...@cable.comcast.com> > --- > Revision 1: > - Alter kernel hook to be able to return packets to the kernel. > - Add tweak to vswitch to use this feature instead of a learning > switch when it encounters OFPP_NORMAL. > > Revision 2: (supercedes patch 2606) > - Refactor the path taken through the datapath to remove one skb clone > and lots of value returns. > - Add capability to insert a packet back to the kernel input queue. > - Add openflow action to send a packet back_to_kernel. > - Update tests/docs. > > Revision 3: (supercedes patch 2651) > - Break the patch into several; > - Datapath back_to_kernel action. > - OpenFlow action back_to_kernel. (requires datapath patch) > - Add tests for back_to_kernel method. > - Abandon the port_normal_mode and OFPP_NORMAL handling in vswitch > patch. > - Alter datapath method from a special output port to a discrete action. > - skb header pointer "cleanup" has proven unnecessary. > - Alter how packets that went via userspace are reinput to the kernel > (no more PACKET_LOOPBACK crud): > - Hijack the tc_verd field, if we have it, in the skb to signal that > the taps can be skipped. This works back to at least 2.6.36 > (which is when the current rx_handler logic was introduced.) > - Proof of concept kernel patch to make this much more efficient. > > > Chris Luke (4): > datapath: Action for returning packets to the kernel > datapath: New kernel function to insert packets async > lib,ofproto: Add 'back_to_kernel' OpenFlow action > doc: Documentation updates for the back_to_kernel patches > > AUTHORS | 1 + > FAQ | 87 ++++++++++++++++++++++++++++++----- > NEWS | 2 + > acinclude.m4 | 3 ++ > datapath/actions.c | 40 +++++++++++++++++ > datapath/datapath.c | 23 ++++++++-- > datapath/datapath.h | 9 +++- > datapath/flow_netlink.c | 6 ++- > datapath/vport-netdev.c | 100 > ++++++++++++++++++++++++++++++++++++----- > datapath/vport.c | 26 ++++++++++- > datapath/vport.h | 4 +- > include/linux/openvswitch.h | 1 + > include/openflow/nicira-ext.h | 1 + > lib/dpif-netdev.c | 1 + > lib/dpif.c | 1 + > lib/odp-execute.c | 4 ++ > lib/odp-util.c | 12 +++++ > lib/ofp-actions.c | 30 +++++++++++++ > lib/ofp-actions.h | 8 ++++ > lib/ofp-parse.c | 4 ++ > lib/ofp-util.def | 1 + > ofproto/ofproto-dpif-xlate.c | 27 +++++++++++ > tests/odp.at | 1 + > tests/ofproto-dpif.at | 15 +++++++ > tests/ovs-ofctl.at | 2 + > utilities/ovs-ofctl.8.in | 7 +++ > 26 files changed, 386 insertions(+), 30 deletions(-) > > -- > 1.7.9.5 > > _______________________________________________ > dev mailing list > dev@openvswitch.org > http://openvswitch.org/mailman/listinfo/dev > _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
