[dpdk-dev] Debugging EAL PCI / Driver Init

[Matthew Hall]

Also, when using the separate libraries the problem still happens:

-lethdev -lrte_cfgfile -lrte_cmdline -lrte_distributor -lrte_hash 
-lrte_ip_frag -lrte_lpm -lrte_malloc -lrte_mbuf -lrte_mempool -lrte_pmd_e1000 
-lrte_pmd_pcap -lrte_pmd_virtio_uio -lrte_pmd_vmxnet3_uio -lrte_port 
-lrte_ring -lrte_table -lrte_timer -lrte_eal -lbsd -ldl -lpcap -lpthread

So it seems there is a special order or link technique which must be used, or 
rte_eal's PCI code won't be able to load the PMD's during PCI probing. Is it 
documented anywhere how to get that to work?

Thanks,
Matthew.

On Sat, Aug 02, 2014 at 08:29:04AM -0700, Matthew Hall wrote:
> I did a bit more experimentation and found the following. If I unmark the 
> rte_igb_pmd_init function as static, and call it directly from my code, the 
> driver will load, and the port count increments to 2:
> 
> EAL: PCI device 0000:01:00.0 on NUMA socket -1
> EAL:   probe driver: 8086:1521 rte_igb_pmd
> EAL:   PCI memory mapped at 0x7f09d45f2000
> EAL:   PCI memory mapped at 0x7f09d4730000
> PMD: eth_igb_dev_init(): port_id 0 vendorID=0x8086 deviceID=0x1521
> 
> EAL: PCI device 0000:01:00.1 on NUMA socket -1
> EAL:   probe driver: 8086:1521 rte_igb_pmd
> EAL:   PCI memory mapped at 0x7f09d0f00000
> EAL:   PCI memory mapped at 0x7f09d472c000
> PMD: eth_igb_dev_init(): port_id 1 vendorID=0x8086 deviceID=0x1521
> 
> So it seems like when you enable these options:
> 
> # Combine to one single library
> CONFIG_RTE_BUILD_COMBINE_LIBS=y
> CONFIG_RTE_LIBNAME="intel_dpdk"
> 
> You don't really get a working DPDK inside of "-lintel_dpdk". Someone 
> suggested linking with "-Xlinker -lintel_dpdk" but that didn't seem to help.
> 
> Is there a secret to getting a single integrated static library, where all of 
> the PMD's end up in the PCI driver list so rte_eal_pci_probe can find them? Or 
> some secret to linking against the combined library which works properly?
> 
> Matthew.
> 
> On Fri, Aug 01, 2014 at 10:51:38AM -0700, Matthew Hall wrote:
> > Hello,
> > 
> > I am running into a problem where Eth driver init works fine in a sample app 
> > and finds my NICs, and the NICs appear in rte_eal_pci_dump(stdout) but they 
> > don't show up in rte_eth_dev_count() even after rte_eal_pci_probe() is called 
> > the same as the sample apps, so my app won't boot.
> > 
> > I have a lot of experience using the older versions of the DPDK where you had 
> > to call the PMD init functions manually but no experience with the later 
> > versions where the DPDK is supposed to init the PMDs itself automatically.
> > 
> > What do I have to do to dump the most possible debug output on why the driver 
> > list for my PCI devices always seems empty? Any places I should look to see 
> > the issue? Maybe I didn't link it together with the right DPDK libs? I used 
> > the combined DPDK static lib libintel_dpdk.a to make things simpler as I had 
> > seen recommended in various places.
> > 
> > Thanks,
> > Matthew.