Re: [dpdk-dev] [PATCH 0/2] lib: move Netlink wrapper to lib

["Nélio Laranjeiro" <nelio.laranjeiro@6wind.com>]

On Thu, Mar 15, 2018 at 04:39:46PM +0100, Thomas Monjalon wrote:
> 14/03/2018 16:17, Stephen Hemminger:
> > On Wed, 14 Mar 2018 13:08:55 +0100
> > Nélio Laranjeiro <nelio.laranjeiro@6wind.com> wrote:
> > > On Tue, Mar 13, 2018 at 02:20:31PM -0700, Stephen Hemminger wrote:
> > > > On Tue, 13 Mar 2018 13:28:25 +0100
> > > > Nelio Laranjeiro <nelio.laranjeiro@6wind.com> wrote:
> > > > >  drivers/net/tap/Makefile                           |   3 +-
> > > > >  drivers/net/tap/rte_eth_tap.c                      |  16 +--
> > > > >  drivers/net/tap/tap_flow.c                         | 118 ++++++++++-----------
> > > > >  drivers/net/tap/tap_netlink.h                      |  42 --------
> > > > >  drivers/net/tap/tap_tcmsgs.c                       |  28 ++---
> > > > >  drivers/net/tap/tap_tcmsgs.h                       |   2 +-
> > > > >  lib/Makefile                                       |   2 +
> > > > >  lib/librte_netlink/Makefile                        |  26 +++++
> > > > >  lib/librte_netlink/meson.build                     |  13 +++
> > > > >  .../librte_netlink/rte_netlink.c                   |  87 +++++++++++----
> > > > >  lib/librte_netlink/rte_netlink.h                   |  43 ++++++++
> > > > >  lib/librte_netlink/rte_netlink_version.map         |  18 ++++
> > > > 
> > > > I might have raised this before; but having yet another netlink library is
> > > > not a great advantage. It would be much better to use a common external library
> > > > libmnl which is already available on every distribution.  
> > > 
> > > The question is more do we really want to have a dependency on a so
> > > small wrapper for a socket interface?
> > 
> > Lots of drivers already have dependencies.
> > And I trust libmnl rather than a reinvented library.
> 
> Are we sure it is commonly installed in distributions?
> 
> This is needed only for TAP and mlx drivers.
> Do we really want to add this dependency as mandatory for everybody
> to compile DPDK with default PMDs?
> 
> I see 4 options:
> 1/ keep duplicated few functions in PMDs
> 2/ use libmnl
> 3/ add the functions in a DPDK lib (this patch)
> 4/ add the functions in EAL
> 
> I would vote for the first option because mlx5 has very minimal
> requirement regarding netlink.
> The first option can give us some time to think about the right way
> to use netlink in the next releases.

I also vote for option 1 until those 4 and maybe more options are
discussed.

-- 
Nélio Laranjeiro
6WIND