Thank you Mark & Michael Qiu for this work. I had looked at the patch series and have some high level comments as inline.
I would like to test these patch on some of the test scenarios. so please send a proper patch series once the DPDK17.11 support is added in OVS. Regards _Sugesh > -----Original Message----- > From: Kavanagh, Mark B > Sent: Friday, December 8, 2017 12:02 PM > To: d...@openvswitch.org; qiud...@chinac.com > Cc: Stokes, Ian <ian.sto...@intel.com>; Loftus, Ciara > <ciara.lof...@intel.com>; > santosh.shu...@caviumnetworks.com; Chandran, Sugesh > <sugesh.chand...@intel.com>; Kavanagh, Mark B > <mark.b.kavan...@intel.com> > Subject: [ovs-dev][RFC PATCH V4 0/9] netdev-dpdk: support multi-segment > mbufs > > Overview > ======== > This patchset introduces support for multi-segment mbufs to OvS-DPDK. > Multi-segment mbufs are typically used when the size of an mbuf is > insufficient > to contain the entirety of a packet's data. Instead, the data is split across > numerous mbufs, each carrying a portion, or 'segment', of the packet data. > mbufs are chained via their 'next' > attribute (an mbuf pointer). > > Use Cases > ========= > i. Handling oversized (guest-originated) frames, which are marked > for hardware accelration/offload (TSO, for example). > > Packets which originate from a non-DPDK source may be marked for > offload; as such, they may be larger than the permitted ingress > interface's MTU, and may be stored in an oversized dp-packet. In > order to transmit such packets over a DPDK port, their contents > must be copied to a DPDK mbuf (via dpdk_do_tx_copy). However, in > its current implementation, that function only copies data into > a single mbuf; if the space available in the mbuf is exhausted, > but not all packet data has been copied, then it is lost. > Similarly, when cloning a DPDK mbuf, it must be considered > whether that mbuf contains multiple segments. Both issues are > resolved within this patchset. > > ii. Handling jumbo frames. > > While OvS already supports jumbo frames, it does so by increasing > mbuf size, such that the entirety of a jumbo frame may be handled > in a single mbuf. This is certainly the preferred, and most > performant approach (and remains the default). However, it places > high demands on system memory; multi-segment mbufs may be > prefereable for systems which are memory-constrained. > > Enabling multi-segment mbufs > ============================ > Multi-segment and single-segment mbufs are mutually exclusive, and the user > must decide on which approach to adopt on init. The introduction of a new > OVSDB field, 'dpdk-multi-seg-mbufs', facilitates this. > > This is a global boolean value, which determines how jumbo frames are > represented across all DPDK ports. In the absence of a user-supplied value, > 'dpdk-multi-seg-mbufs' defaults to false, i.e. multi-segment mbufs must be > explicitly enabled / single-segment mbufs remain the default. > > Setting the field is identical to setting existing DPDK-specific OVSDB > fields: > > ovs-vsctl set Open_vSwitch . other_config:dpdk-init=true > ovs-vsctl set Open_vSwitch . other_config:dpdk-lcore-mask=0x10 > ovs-vsctl set Open_vSwitch . other_config:dpdk-socket-mem=4096,0 > ==> ovs-vsctl set Open_vSwitch . other_config:dpdk-multi-seg-mbufs=true > > > Notes > ===== > This patchset was generated and built against: > - Current HEAD of OvS master[1] + DPDK v17.11 support patchset[2] > - DPDK v17.11 > > [1] 159cc1f ("datapath-windows: Correct endianness for deleting zone.") [2] > https://mail.openvswitch.org/pipermail/ovs-dev/2017-December/341786.html > > --- > > v4: - restructure patchset > - account for 128B ARM cacheline when sizing mbufs > > Mark Kavanagh (5): > netdev-dpdk: fix mbuf sizing > dp-packet: fix reset_packet for multi-seg mbufs > dp-packet: fix put_uninit for multi-seg mbufs > dp-packet: init specific mbuf fields to 0 > netdev-dpdk: support multi-segment jumbo frames > > Michael Qiu (4): > dp-packet: Fix data_len issue with multi-seg mbufs > dp-packet: copy mbuf info for packet copy > dp-packet: copy data from multi-seg. DPDK mbuf > netdev-dpdk: copy large packet to multi-seg. mbufs > > NEWS | 1 + > lib/dp-packet.c | 51 ++++++++++++++++- > lib/dp-packet.h | 26 ++++----- > lib/dpdk.c | 7 +++ > lib/netdev-dpdk.c | 156 ++++++++++++++++++++++++++++++++++++++++++--- > ------ > lib/netdev-dpdk.h | 1 + > vswitchd/vswitch.xml | 20 +++++++ > 7 files changed, 220 insertions(+), 42 deletions(-) > > -- > 1.9.3 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev