Re: [dpdk-dev] [PATCH v2] eal: fix querying DPDK version at runtime

[Thomas Monjalon <thomas@monjalon.net>]

17/03/2021 09:40, David Marchand:
> On Tue, Feb 16, 2021 at 4:13 PM Bruce Richardson
> <bruce.richardson@intel.com> wrote:
> >
> > For using a DPDK application, such as OVS, which is dynamically linked, the
> > DPDK version in use should always report the actual version, not the
> > version used at build time. This incorrect behaviour can be seen by
> > building OVS against one version of DPDK and running it against a later
> > one. Using "ovs-vsctl list Open_vSwitch" to query basic info, the
> > dpdk_version returned will be the build version not the currently running
> > one - which can be verified using the DPDK telemetry library client.
> >
> >   $ sudo ovs-vsctl list Open_vSwitch | grep dpdk_version
> >   dpdk_version        : "DPDK 20.11.0-rc4"
> >
> >   $ echo quit | sudo dpdk-telemetry.py
> >   Connecting to /var/run/dpdk/rte/dpdk_telemetry.v2
> >   {"version": "DPDK 21.02.0-rc2", "pid": 405659, "max_output_len": 16384}
> >   -->
> >
> > To fix this, we need to convert the rte_version() function, and any other
> > necessary parts of the rte_version.h, to be actual functions in EAL, not
> > just inlines/macros. The only complication in doing so is that telemetry
> > library cannot call rte_version() directly, and instead needs the version
> > string passed in on init.
> >
> > Fixes: af75078fece3 ("first public release")
> > Cc: stable@dpdk.org
> 
> 
> > diff --git a/lib/librte_eal/include/rte_version.h b/lib/librte_eal/include/rte_version.h
> > index f7a3a1ebc..2f3f727b4 100644
> > --- a/lib/librte_eal/include/rte_version.h
> > +++ b/lib/librte_eal/include/rte_version.h
> > @@ -28,38 +28,47 @@ extern "C" {
> >   * All version numbers in one to compare with RTE_VERSION_NUM()
> >   */
> >  #define RTE_VERSION RTE_VERSION_NUM( \
> > -                       RTE_VER_YEAR, \
> > -                       RTE_VER_MONTH, \
> > -                       RTE_VER_MINOR, \
> > -                       RTE_VER_RELEASE)
> > +                       rte_version_year(), \
> > +                       rte_version_month(), \
> > +                       rte_version_minor(), \
> > +                       rte_version_release())
> 
> It breaks SPDK and applications relying on RTE_VERSION in preprocessor
> directives.
> RTE_VERSION* macros should be left alone, and applications that need
> the runtime value should call rte_version().

Yes, sorry for not catching it before merge.

> See logs in https://lab.dpdk.org/results/dashboard/results/results-uploads/test_runs/2f636aaf4ce244eba20844f9ff006033/log_upload_file/2021/3/dpdk_6857cb635821_2021-03-17_06-34-34_NA.zip

My bad ignoring SPDK build, probably because of other issues there were.

I've sent a fix:
https://patches.dpdk.org/project/dpdk/patch/20210317093124.965624-1-thomas@monjalon.net/