Re: [dpdk-dev] Debugging EAL PCI / Driver Init

[Matthew Hall <mhall@mhcomputing.net>]

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.