Re: [dpdk-stable] [dpdk-dev] 19.11.4 patches review and test

["Stokes, Ian" <ian.stokes@intel.com>]

> Hi,
> 
> Yes , OVS was using pkg-config even before these patches were rolled out.
> But it always used to pick the DPDK shared libs by default for OVS even on using
> the -Bstatic/-Bshared flags.
> These patches from Bruce simplify the process from DPDK side without having
> the user to specify them.
> Moreover, with these patches , the problem of shared DPDK libs always being
> picked instead of static was not seen any more with a bit of changes from the
> OVS side as well.
> http://patchwork.ozlabs.org/project/openvswitch/patch/20200707141126.7141
> 4-1-sunil.pai.g@intel.com/ .
> The patches for ovs-master are ready as well and will them out soon.
> 
> Thanks and Regards,
> Pai G, Sunil
> Sunil

Hi Folks,

From the OVS side there was a question WRT why we couldn't use meson in our Travis tests to build DPDK for OVS supporting 19.11.x, in this case it was related to the changes described by Sunil above and hence why the backport was requested. 

It doesn't have a huge impact on OVS, we can still use 19.11.4 if the patches are removed, however I suspect these changes are also on DPDK main branch at this point and will be part of 20.11? So eventually when we move to 20.11 the same issues may be encountered, maybe that preferable if we are change LTS versions.

From the OVS side we can look to upstream meson support in the dpdk-latest branch and then integrate it when 20.11 is released, but it would be nice to support it before then if possible.

Regards
Ian
> 
> > -----Original Message-----
> > From: Bruce Richardson <bruce.richardson@intel.com>
> > Sent: Tuesday, September 1, 2020 6:18 PM
> > To: Christian Ehrhardt <christian.ehrhardt@canonical.com>
> > Cc: Luca Boccassi <bluca@debian.org>; stable@dpdk.org; dev
> > <dev@dpdk.org>; Pai G, Sunil <sunil.pai.g@intel.com>; Stokes, Ian
> > <ian.stokes@intel.com>
> > Subject: Re: [dpdk-dev] 19.11.4 patches review and test
> >
> > On Tue, Sep 01, 2020 at 02:32:26PM +0200, Christian Ehrhardt wrote:
> > > On Tue, Sep 1, 2020 at 10:30 AM Luca Boccassi <bluca@debian.org> wrote:
> > > >
> > > > On Tue, 2020-08-18 at 19:12 +0100, Luca Boccassi wrote:
> > > > > Hi all,
> > > > >
> > > > > Here is a list of patches targeted for stable release 19.11.4.
> > > > >
> > > > > The planned date for the final release is August 31st.
> > > > >
> > > > > Please help with testing and validation of your use cases and
> > > > > report any issues/results with reply-all to this mail. For the
> > > > > final release the fixes and reported validations will be added
> > > > > to the release
> > notes.
> > > > >
> > > > > A release candidate tarball can be found at:
> > > > >
> > > > >     https://dpdk.org/browse/dpdk-stable/tag/?id=v19.11.4-rc1
> > > > >
> > > > > These patches are located at branch 19.11 of dpdk-stable repo:
> > > > >     https://dpdk.org/browse/dpdk-stable/
> > > > >
> > > > > Thanks.
> > > > >
> > > > > Luca Boccassi
> > > >
> > > > Microsoft's regression tests are still running, delaying until
> > > > Thursday the 3rd. Apologies for any inconvenience.
> > >
> > > Due to report on OVS failing to build I happened to find that
> > > 19.11.4 has massively changed linking.
> > > => https://paste.ubuntu.com/p/znCRR4gpjP/
> > >
> > > This was meant to be helpful for sure and I assume is around:
> > > 48f7fd27f6 build/pkg-config: prevent overlinking
> > > 2d1535d592 build/pkg-config: improve static linking flags
> > > 9fb13a12c1 build/pkg-config: output drivers first for static build
> > > 59b108d824 build/pkg-config: move pkg-config file creation
> > > aea915e944 devtools: test static linkage with pkg-config
> > >
> > > But overlinking has effectively become underlinking now
> > > https://launchpadlibrarian.net/495845224/buildlog_ubuntu-groovy-amd64.
> > > openvswitch_2.13.1-0ubuntu2~ppa1_BUILDING.txt.gz
> > >
> > > /usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/10/../../../x86_64-linux-
> > gnu/librte_pmd_ring.a(net_ring_rte_eth_ring.c.o):
> > > in function `rte_eth_from_rings':
> > > (.text+0x91c): undefined reference to `rte_vdev_init'
> > > /usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/10/../../../x86_64-linux-
> > gnu/librte_pmd_ring.a(net_ring_rte_eth_ring.c.o):
> > > in function `vdrvinitfn_pmd_ring_drv':
> > > (.text.startup+0x28): undefined reference to `rte_vdev_register'
> > > collect2: error: ld returned 1 exit status
> > >
> > > Also as you can see in the pastebin above, CFlags and Libs massively
> > > shrunk and likely too much so.
> > >
> > > Given that this should be a stable release I'd ask to back out those
> > > changes so that a test build creates the same .pc file as before -
> > > would that make sense?
> > >
> > >
> > Adding some OVS folks on CC.
> >
> > The request for backporting these actually came from the OVS side,
> > since they were deemed necessary to enable OVS to switch to use DPDK
> > pkg-config rather than the older approach using a makefile-based
> > build. However, it appears you guys were already building OVS using
> > the pkg-config file, and since this causes issues where there were none,
> backing it out seems a prudent choice.
> >
> > Ian, Sunil, any comments here.
> >
> > Regards
> > /Bruce