On 12/12/22 17:17, Frode Nordahl wrote: > On Mon, Dec 12, 2022 at 2:55 PM Frode Nordahl > <[email protected]> wrote: >> >> On Mon, Dec 12, 2022 at 12:20 PM Ilya Maximets <[email protected]> wrote: >>> >>> On 12/12/22 09:40, Eelco Chaudron wrote: >>>> >>>> >>>> On 10 Dec 2022, at 3:16, Ilya Maximets wrote: >>>> >>>>> This patch set allows OVS to build with libxdp and newer libbpf. >>>>> It also enables AF_XDP support by default as long as all the >>>>> dependencies are available. >>>> >>>> Hi Ilya, >>>> >>>> I did not yet review the patch, but I do not like enabling AF_XPD support >>>> by default for the following reasons: >>> >>> Hi, Eelco. Thanks for taking a look! >>> >>>> >>>> - I still believe AF_XDP support in OVS has not had many field trials, >>>> so I would still classify this as an “experimental” feature. >>> >>> This patch set doesn't make the feature non-experimental. >>> There is still a warning about that in the documentation. >>> See the patch 3/6. >>> >>> In general, we do build a lot of experimental features by >>> default and users can enable these features. For example, >>> some PMD management features, userspace TSO or AVX512 support. >>> >>> Enabling the build may increase the number of field trials >>> performed by enthusiastic users, so should have some >>> positive impact on development in general. I've seen an >>> increased interest in trying out this feature recently. >>> Also, the feature doesn't impact existing users, they still >>> need to explicitly create ports of afxdp type in order to >>> use them. The code is pretty much independent from other >>> parts of OVS. >>> >>>> - Reversing build option logic might cause problems for distributions> >>>> (or at least require people to think, as now they have to explicitly >>>> disable it). >>> >>> This is true for every other feature. And I added an explicit >>> disabling for Debian and Fedora packaging in the patch 3/6. >>> In general, distributions should not blindly take every >>> new release without checking the NEWS anyway. >> >> fwiw; we have interest in AF_XDP too and I'm currently evaluating if >> we have the bits aligned to enable this by default in Debian too. >> >> One challenge is that in Debian libbpf 0.8 is a compatibility package >> and the development package is only available as a 1.x, and at the >> same time xdp-tools is linked with libbpf 0.8. So when building OVS it >> will try to link with both libbpf 0.8 via libxdp and libbpf 1.x, which >> I think may be preventing this from working right now. >> >> That is our problem to sort though, and we have no issue with having >> this important feature be enabled by default in the upstream build >> system. > > ftr; This was already sorted in Debian, I was using an out of date system. > > With that fixed, it does appear that OVS or xdp-tools may need an > update to work with libbpf 1.x: > 2022-12-12T16:01:32.800Z|00067|netdev_afxdp|WARN|libbpf: prog > 'xdp_dispatcher': missing BPF prog type, check ELF section name > 'xdp/dispatcher' > 2022-12-12T16:01:32.800Z|00068|netdev_afxdp|WARN|libbpf: prog > 'xdp_dispatcher': failed to load: -22 >
Hmm. OVS doesn't load xdp programs on its own, it relies on libbpf to load a default program. BTW, are you testing with the second patch of this patch set applied? Otherwise, OVS will use some deprecated APIs that might be broken. Best regards, Ilya Maximets. _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
