Re: [dpdk-users] Can't capture Jumbo Frames with rte.lib.mk

[Filip Janiszewski <contact@filipjaniszewski.com>]

One addition: Apparently also the timestamps are not present in the
captured packets while building the example code as a library (but they
are present if the code is built as rte.app.mk), it seems that the
offload configuration is being ignored.

Any idea on what's going on?

Thanks

Il 11/03/19 14:41, Filip Janiszewski ha scritto:
> Hi,
> 
> (The complete code of the example application is available at
> https://github.com/fjanisze/dpdk-jf-test)
> 
> While working on the sample code I made a strange discovery, the same
> identical piece of software works and capture jumbo frame while compile
> with $(RTE_SDK)/mk/rte.extapp.mk but it does not work while compiled
> with $(RTE_SDK)/mk/rte.lib.mk, by that I mean that I cannot capture
> Jumbo Frames.
> 
> In the repo I have the same identical piece of code build in two
> ways, in ./app folder it is built as regular application using a DPDK
> makefile which calls $(RTE_SDK)/mk/rte.extapp.mk (check the code please).
> 
> in the ./lib folder you have the same piece of code, but instead of
> being inside the main(int, char**) function it is placed inside the lib
> within the test(int,char**) function, to call the test function from the
> library I've build a little test.c piece of code that do the following:
> 
> .
> extern int test(int argc, char**argv);
> 
> int main(int argc, char** argv)
> {
>     return test(argc,argv);
> }
> .
> 
> I build the test.c application with:
> 
>  gcc -Wl,--whole-archive -ldpdk -Wl,--no-whole-archive -lmlx4 -lmlx5 -lm
> -libverbs -lrte_eal -L. -lpthread -lnuma -ldl test.c -ljftest -o test
> 
> please note that jftest.a must be present in the building dir, this .a
> file is create by calling make inside ./lib (where the DPDK Makefile is
> present).
> 
> If you make sure to configure RTE_SDK then you can build the two test
> application by:
> 
> A) Entering ./app and calling make
> B) Entering ./lib and calling make, then copying from ./lib/build/lib/
> the newly create libjftest.a to the ./lib folder and calling the command
> I show you above to build the test executable:
> 
>  gcc -Wl,--whole-archive -ldpdk -Wl,--no-whole-archive -lmlx4 -lmlx5 -lm
> -libverbs -lrte_eal -L. -lpthread -lnuma -ldl test.c -ljftest -o test
> 
> Please note that the code in ./app/main.c and ./lib/main.c is absolutely
> identical, the only different is that one is build as a lib (.a) and the
> second as ELF (executable).
> 
> The build from A can capture Jumbo Frame, the build from B cannot
> capture Jumbo Frames.
> 
> I've a test PCAP with two packets, one of size 9022 bytes the other
> 1522, I send those packets in a loop to my box to test the output of the
> two test applications, on my development box (A) is generating the
> following output:
> 
> .
> EAL: Detected 28 lcore(s)
> EAL: Detected 1 NUMA nodes
> EAL: Multi-process socket /var/run/dpdk/rte/mp_socket
> EAL: No free hugepages reported in hugepages-1048576kB
> EAL: Probing VFIO support...
> EAL: PCI device 0000:00:1f.6 on NUMA socket 0
> EAL:   probe driver: 8086:15b8 net_e1000_em
> EAL: PCI device 0000:b3:00.0 on NUMA socket 0
> EAL:   probe driver: 15b3:1015 net_mlx5
> net_mlx5: MPLS over GRE/UDP tunnel offloading disabled due to old
> OFED/rdma-core version or firmware configuration
> EAL: PCI device 0000:b3:00.1 on NUMA socket 0
> EAL:   probe driver: 15b3:1015 net_mlx5
> net_mlx5: MPLS over GRE/UDP tunnel offloading disabled due to old
> OFED/rdma-core version or firmware configuration
> Running DPDK 19.02.0
> Captured pkt, len 9022, nb segs 5
> Captured pkt, len 1522, nb segs 1
> Captured pkt, len 9022, nb segs 5
> Captured pkt, len 1522, nb segs 1
> Captured pkt, len 9022, nb segs 5
> Captured pkt, len 1522, nb segs 1
> Captured pkt, len 9022, nb segs 5
> Captured pkt, len 1522, nb segs 1
> .
> . <CUT>
> 
> (B) is generating the following output:
> 
> .
> EAL: Detected 28 lcore(s)
> EAL: Detected 1 NUMA nodes
> EAL: Multi-process socket /var/run/dpdk/rte/mp_socket
> EAL: No free hugepages reported in hugepages-1048576kB
> EAL: Probing VFIO support...
> EAL: PCI device 0000:00:1f.6 on NUMA socket 0
> EAL:   probe driver: 8086:15b8 net_e1000_em
> EAL: PCI device 0000:b3:00.0 on NUMA socket 0
> EAL:   probe driver: 15b3:1015 net_mlx5
> net_mlx5: MPLS over GRE/UDP tunnel offloading disabled due to old
> OFED/rdma-core version or firmware configuration
> EAL: PCI device 0000:b3:00.1 on NUMA socket 0
> EAL:   probe driver: 15b3:1015 net_mlx5
> net_mlx5: MPLS over GRE/UDP tunnel offloading disabled due to old
> OFED/rdma-core version or firmware configuration
> Running DPDK 19.02.0
> Captured pkt, len 1522, nb segs 1
> Captured pkt, len 1522, nb segs 1
> Captured pkt, len 1522, nb segs 1
> Captured pkt, len 1522, nb segs 1
> Captured pkt, len 1522, nb segs 1
> .<CUT>
> 
> The same piece of software build in two different way generate two
> different outputs, any suggestion on what might be the issue here?
> 
> Thanks
> 

-- 
BR, Filip
+48 666 369 823