Re: [dpdk-dev] building shared library

[Newman Poborsky <newman555p@gmail.com>]

It works!!!  Thanks everybody!

I wasn't using '-Wl,--no-as-needed'  while compiling, so no PMD driver was
linked and hence no constructor called. After putting this options, it
finally works.

Again, thank you very much, I could never figure out all these steps on my
own!

BR,
Newman

On Tue, Nov 11, 2014 at 4:54 PM, Neil Horman <nhorman@tuxdriver.com> wrote:

> On Tue, Nov 11, 2014 at 03:26:04PM +0000, De Lara Guarch, Pablo wrote:
> >
> >
> > > -----Original Message-----
> > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Newman Poborsky
> > > Sent: Tuesday, November 11, 2014 3:17 PM
> > > To: Gonzalez Monroy, Sergio
> > > Cc: dev@dpdk.org
> > > Subject: Re: [dpdk-dev] building shared library
> > >
> > > Hi,
> > >
> > > after building DPDK libs as shared libraries and linking it, I'm back
> to my
> > > first problem: rte_eal_driver_register() never gest called and my app
> > > crashes since there are no drivers registered.  As previously
> mentioned, in
> > > regular DPDK user app this functions is called for every driver before
> > > main(). How?
> >
> > If I am not wrong here, you have to use the -d option to specify the
> driver you want to use.
> >
> > Btw, the option you were looking for can be found in
> config/common_linuxapp or config/common_bsdapp.
> >
>
> Alternatively, when you link your application you can speify
> -llibrte_pmd_<driver> and your applicaion should call all the constructors
> when
> the dynamic loader hits your binaries DT_NEEDED table.  Thats how you can
> avoid
> the command line specification.
>
> Neil
>
> > Pablo
> > >
> > > BR,
> > > Newman
> > >
> > > On Tue, Nov 11, 2014 at 3:44 PM, Newman Poborsky
> > > <newman555p@gmail.com>
> > > wrote:
> > >
> > > > Hi Sergio,
> > > >
> > > > no, that sounds good, thank you.  Since I'm not that familiar with
> DPDK
> > > > build system, where should this option be set? In 'lib' folder's
> Makefile?
> > > >
> > > > Thank you once again!
> > > >
> > > > BR,
> > > > Newman
> > > >
> > > > On Tue, Nov 11, 2014 at 3:18 PM, Sergio Gonzalez Monroy <
> > > > sergio.gonzalez.monroy@intel.com> wrote:
> > > >
> > > >> On Tue, Nov 11, 2014 at 01:10:29PM +0100, Newman Poborsky wrote:
> > > >> > Hi,
> > > >> >
> > > >> > I want to build one .so file with my app (it contains API that I
> want to
> > > >> > call through JNI) and all DPDK libs that I use in my app.
> > > >> >
> > > >> > As I've already mentioned, when I build and start my dpdk app as a
> > > >> > standalone application, I can see that before main() is called,
> there
> > > >> is a
> > > >> > call to 'rte_eal_driver_register()' function for every driver.
> When I
> > > >> build
> > > >> > .so file, this does not happen and no driver is registered so
> everyting
> > > >> > after rte_eal_init() fails.
> > > >> >
> > > >> Hi Newman,
> > > >>
> > > >> AFAIK the current build system does not support that.
> > > >>
> > > >> You can build DPDK as shared libs by setting the following config
> option:
> > > >> CONFIG_RTE_BUILD_SHARED_LIB=y
> > > >>
> > > >> Then build your app as an .so that links against DPDK libs, so you
> have
> > > >> explicit dependencies (such dependencies should show with ldd).
> > > >>
> > > >> Is there any reason why you want everything to be a single .so ?
> > > >>
> > > >> I don't know much about how Java loads DSOs but I reckon that it
> must
> > > >> resolve
> > > >> explicit dependencies such as libc.
> > > >>
> > > >> Thanks,
> > > >> Sergio
> > > >>
> > > >>
> > > >> >
> > > >> > BR,
> > > >> > Newman
> > > >> >
> > > >>
> > > >
> > > >
>