Hi Wisam, When we perform a similar test on i40e, we find an important thing: there is a max number limit for mbuf->nb_segs. When the number of MBUF segments of the packet is larger than this limit, the packet will be dropped.
The GROed packet has multiple MBUF segments. For vhost-dpdk, it doesn't have limit for the number of segments. But it's not the same for all NIC drivers. So I suggest you to check if the MLX driver has this limit too. Thanks, Jiayu > -----Original Message----- > From: Wisam Monther [mailto:[email protected]] > Sent: Wednesday, September 6, 2017 7:18 PM > To: Hu, Jiayu <[email protected]> > Cc: [email protected]; Raslan Darawsheh <[email protected]>; Shahaf > Shuler <[email protected]> > Subject: RE: Unable to merge packets using GRO feature > > Hi Jiayu, > > Any comment regard what I described? > > BRs, > Wisam Jaddo > > -----Original Message----- > From: Wisam Monther > Sent: Tuesday, August 29, 2017 10:49 AM > To: 'Hu, Jiayu' > Cc: [email protected]; Raslan Darawsheh; Shahaf Shuler > Subject: RE: Unable to merge packets using GRO feature > > Hi Jiayu, > > Let me re-describe my topology in a better way, see attached image. > And it is connected physically as described, and I'm using it with MTU > size=1500 in order to make sure Every port can handle it. > > And this is the exact connection between the interfaces, so I'm sure the > packets received in NIC B machine B is coming from the testpmd with GRO > enabled. > > But even so, I intentionally made the packet size 1500, to be divided into 3 * > ( 500) fragments using the TSO, and then merged into 1500 packet again in > the GRO. > So the every machine can manage this mtu size. > > The thing that I need to test GRO with each setups types, "VMs with > Baremetal with pass through with VFs etc...". > So I need to see the feature works on least work, it would be nice to send > IPV4_TCP fragmented packet using "scapy, Iperf" > And check the fwd packet from GRO directly. > > BRs, > Wisam Jaddo > > -----Original Message----- > From: Hu, Jiayu [mailto:[email protected]] > Sent: Tuesday, August 29, 2017 4:51 AM > To: Wisam Monther > Cc: [email protected]; Raslan Darawsheh; Shahaf Shuler > Subject: RE: Unable to merge packets using GRO feature > > Hi Wisam, > > In the picture of your experiment topology, I guess NIC B in the machine B is > connected with another interface physically. If so, the packets that tcpdump > captures are from the physical link. However, packets after GROed are multi- > segment large packets, which are larger than MTU. I am not sure if you have > make other configurations to enable these large packets to pass the physical > link, and there is jumbo frame size limit for different NICs. So would you > please to check this? BTW, you can use the VM to test this GRO feature, > since large packets can always pass to the VM. > > Thanks, > Jiayu > > > -----Original Message----- > > From: Wisam Monther [mailto:[email protected]] > > Sent: Monday, August 28, 2017 3:37 PM > > To: Hu, Jiayu <[email protected]> > > Cc: [email protected]; Raslan Darawsheh <[email protected]>; Shahaf > > Shuler <[email protected]> > > Subject: RE: Unable to merge packets using GRO feature > > > > Hi Jiayu, > > > > I'm sorry for bothering you, but could you conform that the feature is > > working probably Because, what I ever did, I couldn't get the merged > > packets. > > > > BRs, > > Wisam Jaddo > > > > -----Original Message----- > > From: Wisam Monther > > Sent: Thursday, August 24, 2017 9:15 AM > > To: 'Hu, Jiayu' > > Cc: [email protected]; Raslan Darawsheh; Shahaf Shuler > > Subject: RE: Unable to merge packets using GRO feature > > > > Hi, > > > > I'm using Mellanox NICs, and it is supporting parse packet types. > > > > Best regards, > > Wisam Jaddo > > > > -----Original Message----- > > From: Hu, Jiayu [mailto:[email protected]] > > Sent: Thursday, August 24, 2017 8:47 AM > > To: Wisam Monther > > Cc: [email protected]; Raslan Darawsheh; Shahaf Shuler > > Subject: RE: Unable to merge packets using GRO feature > > > > Hi, > > > > Can you tell me what's the NIC type of the GRO-enabled port? > > > > Since GRO library uses mbuf->packet_type to parse packet headers, > > applications need to fill this value before calling GRO reassembly APIs. > > Otherwise, the GRO can't work correctly. > > > > In csum forwarding engine of testpmd, packet_type is filled by NIC drivers. > > The csum forwarding engine won't set this value. So if your NIC > > doesn’t support to parse packet types, the value of packet_type is 0 > > and GRO can't work correctly. > > > > BRs, > > Jiayu > > > > > -----Original Message----- > > > From: Wisam Monther [mailto:[email protected]] > > > Sent: Tuesday, August 22, 2017 9:25 PM > > > To: Hu, Jiayu <[email protected]> > > > Cc: [email protected]; Raslan Darawsheh <[email protected]>; > Shahaf > > > Shuler <[email protected]> > > > Subject: RE: Unable to merge packets using GRO feature > > > > > > Yes it is, > > > The fragmented packets comes from port1 / NIC b from machine A to > > > port > > > 1 in NIC A for machine b So it's received on the port '1', which is > > > configured gro active on this port. > > > > > > Best regards, > > > Wisam Jaddo > > > > > > -----Original Message----- > > > From: Hu, Jiayu [mailto:[email protected]] > > > Sent: Tuesday, August 22, 2017 4:21 PM > > > To: Wisam Monther > > > Cc: [email protected]; Raslan Darawsheh; Shahaf Shuler > > > Subject: RE: Unable to merge packets using GRO feature > > > > > > Hi, > > > > > > > -----Original Message----- > > > > From: Wisam Monther [mailto:[email protected]] > > > > Sent: Tuesday, August 22, 2017 7:07 PM > > > > To: Hu, Jiayu <[email protected]> > > > > Cc: [email protected]; Raslan Darawsheh <[email protected]>; > > Shahaf > > > > Shuler <[email protected]> > > > > Subject: RE: Unable to merge packets using GRO feature > > > > > > > > Hey Jiayu, > > > > > > > > Thank you for your reply. > > > > I tried what you said with the csum at fwd mode. > > > > Even so the GRO didn't works fine. > > > > > > > > I even tested with a new methodology. > > > > Two machines with two different nic for each. > > > > The methodology that I used to test it is described in the attached > > > > file. > > > > > > > > What I did from gro side: > > > > """ > > > > testpmd>gro on 1 > > > > > > Does the port number of NIC A in machine B is '1'? When you enable > > > GRO for port '1', Testpmd only tries to merge packets received from port > '1'. > > > > > > BRs, > > > Jiayu > > > > > > > Testpmd>set fwd csum > > > > Testpmd>start > > > > """ > > > > And the packet with correct dst mac. > > > > > > > > Best regards, > > > > Wisam Jaddo > > > > -----Original Message----- > > > > From: Jiayu Hu [mailto:[email protected]] > > > > Sent: Monday, August 21, 2017 12:14 PM > > > > To: Wisam Monther > > > > Cc: Thomas Monjalon; [email protected]; Raslan Darawsheh; Shahaf > > > > Shuler > > > > Subject: Re: Unable to merge packets using GRO feature > > > > > > > > Hi, > > > > > > > > On Mon, Aug 21, 2017 at 07:25:23AM +0000, Wisam Monther wrote: > > > > > Hello Guys, > > > > > > > > > > > > > > > > > > > > I hope this finds you well, I’m trying to test the GRO feature. > > > > > But I’m stuck with this scenario. > > > > > > > > > > As you know, GRO is only support TCP_IPV4 packet until now. > > > > > > > > > > So I’m trying to test the basic functionality of the feature, as > following: > > > > > > > > > > Start testpmd: > > > > > > > > > > “”” > > > > > > > > > > ./x86_64-native-linuxapp-gcc/build/app/test-pmd/testpmd -n 4 -w > > > > > 00:0a.0 -w > > > > > 00:09.0 -- --burst=64 --mbcache=512 --portmask 0xf -i > > > > > --txd=512 > > > > > --rxd=512 > > > > > --nb-cores=9 --rxq=2 --txq=2 --txqflags=0 > > > > > > > > > > “”” > > > > > > > > > > > > > > > > > > > > Then enable GRO at the two ports: > > > > > > > > > > “”” > > > > > > > > > > Testpmd>gro on 0 > > > > > > > > > > Testpmd>gro on 1 > > > > > > > > When use GRO in testpmd, there are following things to notice: > > > > > > > > 1. In testpmd, GRO is supported by csum forwarding engine. > > > > Therefore, please use 'set fwd csum' to switch forwarding engine. > > > > > > > > 2. By default, csum forwarding engine compulsorily changes > > > > ethernet addresses. So please make sure that MAC addresses are > correct. > > > > > > > > 3. When enable GRO for port0, csum forwarding engine will merge > > > > packets received from port0. If there are no packets from port1 to > > > > port0, you don't need to enable GRO for port1. > > > > > > > > 4. GRO library doesn't re-calculate checksums for merged packets. > > > > If you want merged packets have correct checksum, please select HW > > > > IP and HW TCP checksum calculation for the port which the merged > > > > packets are transmitted to in csum forwarding engine. > > > > This is because the merged packets are multi-segment mbufs, but > > > > csum forwarding engine doesn't support to calculate checksums for > > > > multi-segment mbufs in SW. So we need to select HW checksum > > offloading. > > > > > > > > e.g. If data flow is "packets -> port0 -> port1", commands used in > > testpmd: > > > > gro on port0 > > > > set fwd csum > > > > csum set ip hw port1 > > > > csum set tcp hw port1 > > > > > > > > > > > > Besides, you need to make sure that your PMD driver doesn't use > > > > vector TX function, since vector function doesn't support checksum > > offloading. > > > > > > > > > > > > > > “”” > > > > > > > > > > > > > > > > > > > > And trying to send TCP_IPV4 fragmented packet “packet with > > > > > length > > > > > 1500 fragmented to three packets of 500” > > > > > > > > > > “”” > > > > > > > > > > p=Ether(src=get_if_hwaddr('ens10'), dst= > > > > > '24:8A:07:88:26:6B')/IP()/TCP() > > > > > > > > > > p.add_payload('F'*(1500 - len(p))) > > > > > > > > > > frags=fragment(p,fragsize=500) > > > > > > > > > > for fragment in frags: > > > > > > > > > > sendp(fragment, iface='ens10') > > > > > > > > > > “”” > > > > > > > > > > > > > > > > > > > > But the testpmd forward the packets as it is, “ doesn’t do any merge” > > > > > > > > > > > > > > > > > > > > Tcpdump at the TG side, > > > > > > > > > > The sending fragmets using ens10: > > > > > > > > > > #tcpdump –I ens10 –vvven > > > > > > > > > > 15:45:29.083514 24:8a:07:88:26:5b > 24:8a:07:88:26:6b, ethertype > > > > > IPv4 (0x0800), length 538: (tos 0x0, ttl 64, id 1, offset 0, > > > > > flags [+], proto Options (0), length 524) > > > > > > > > > > 127.0.0.1 > 127.0.0.1: ip-proto-0 504 > > > > > > > > > > 15:45:29.115266 24:8a:07:88:26:5b > 24:8a:07:88:26:6b, ethertype > > > > > IPv4 (0x0800), length 538: (tos 0x0, ttl 64, id 1, offset 504, > > > > > flags [+], proto Options (0), length 524) > > > > > > > > > > 127.0.0.1 > 127.0.0.1: ip-proto-0 > > > > > > > > > > 15:45:29.147258 24:8a:07:88:26:5b > 24:8a:07:88:26:6b, ethertype > > > > > IPv4 (0x0800), length 492: (tos 0x0, ttl 64, id 1, offset 1008, > > > > > flags [none], proto Options (0), length 478) > > > > > > > > > > 127.0.0.1 > 127.0.0.1: ip-proto-0 > > > > > > > > > > > > > > > > > > > > #tcpdump -i ens9 –vvven /// here will be received the forwarded > > > > > packets from > > > > > testpmd: > > > > > > > > > > 15:45:29.083996 24:8a:07:88:26:5b > 24:8a:07:88:26:6b, ethertype > > > > > IPv4 (0x0800), length 538: (tos 0x0, ttl 64, id 1, offset 0, > > > > > flags [+], proto Options (0), length 524) > > > > > > > > > > 127.0.0.1 > 127.0.0.1: ip-proto-0 504 > > > > > > > > > > 15:45:29.115425 24:8a:07:88:26:5b > 24:8a:07:88:26:6b, ethertype > > > > > IPv4 (0x0800), length 538: (tos 0x0, ttl 64, id 1, offset 504, > > > > > flags [+], proto Options (0), length 524) > > > > > > > > > > 127.0.0.1 > 127.0.0.1: ip-proto-0 > > > > > > > > > > 15:45:29.147492 24:8a:07:88:26:5b > 24:8a:07:88:26:6b, ethertype > > > > > IPv4 (0x0800), length 492: (tos 0x0, ttl 64, id 1, offset 1008, > > > > > flags [none], proto Options (0), length 478) > > > > > > > > > > 127.0.0.1 > 127.0.0.1: ip-proto-0 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Am I doing something wrong?! Or it is a bug. > > > > > > > > > > è As you see the tcpdump shows the offset of each fragment, and > > > > > testpmd prints L4_FRAG, so the both are recognizing that this is > > > > > a > > > > fragmented packet. > > > > > > > > GRO library merges TSOed/GSOed packets, whose IP IDs and TCP > > > sequences > > > > are both consecutive. If input packets have same IP IDs, no > > > > packets will be merged. > > > > > > > > BTW, you can use iperf to test GRO feature. > > > > > > > > Best Regards, > > > > Jiayu > > > > > > > > > > > > > > > > > > > > > > > > Best regards, > > > > > > > > > > Wisam Jaddo > > > > > > > > > > > > > > >
