[dpdk-users] RTE_REGISTER_BUS

[Gaëtan Rivet]

testpmd works with all DPDK devices, PCI included.

Use GDB and break on businitfn_pci, main. Check that the PCI register
function is called, and then the state of the bus list. You can also
break on rte_bus_scan().

If you don't see the PCI bus anywhere, a possible explanation is that
the bus is disabled in your build/.config file.

Gaëtan

On Tue, Nov 26, 2019 at 09:15:42AM +0530, Gadre Nayan wrote:
> Hi,
> 
> Thanks Rivet.
> I was checking the testpmd application to test if my PMD is registered
> on the PCI device list.
> With the softnic pmd, rte_eal_init calls vdev_scan()
> 
> But when I run testpmd with options: ./testpmd -l 0-3 -n 4 -- i
> it again calls vdev_scan().
> Also only virtual device drivers are getting registered through
> rte_vdev_register.
> 
> I was expecting it to register rte_pci_register then call
> rte_pci_scan() and then subsequently rte_pci_probe()
> 
> Does testpmd work with PCI devices or only Vdevs.
> I am trying to write my own PMD for a NIC on my laptop from Realtek.
> 
> Thanks
> Nayan
> 
> On Mon, Nov 25, 2019 at 8:55 PM Gaëtan Rivet <gaetan.rivet at 6wind.com> wrote:
> >
> > On Mon, Nov 25, 2019 at 08:13:00PM +0530, Gadre Nayan wrote:
> > > Hi,
> > >
> > > I am trying to understand RTE_REGISTER_BUS for PCI Bus.
> > >
> > > 1. Load uio, igb_uio, bind the NIC with igb_uio.
> > > 2. load the application.
> > >
> > > Step 1, is mostly about registering Drivers with the PCI bus.
> > > I am looking at when does RTE_REGISTER_BUS get called in this process.
> > >
> > > Thanks
> > > Nayan
> >
> > Hello,
> >
> > RTE_REGISTER_ functions all uses RTE_INIT_PRIO(n) macro.
> > This macro will only add the GCC attribute __attribute__((constructor(n), used))
> > to the symbole defined with RTE_INIT_PRIO() (attribute supported by all
> > major compiler).
> >
> > This attribute adds the related function to the .init section of the
> > generated ELF. This section is executed before the main() of the
> > program.
> >
> > This allows libraries to define init and cleanup code that is executed
> > automatically when linking against the lib.
> >
> > --
> > Gaėtan Rivet
> > 6WIND

-- 
Gaëtan Rivet
6WIND