Re: [PATCH bpf-next v2 11/11] selftests/xsk: introduce XSKTEST_ETH environment variable

[Maciej Fijalkowski <maciej.fijalkowski@intel.com>]

On Fri, Aug 25, 2023 at 03:03:58PM +0200, Magnus Karlsson wrote:
> On Fri, 25 Aug 2023 at 14:57, Maciej Fijalkowski
> <maciej.fijalkowski@intel.com> wrote:
> >
> > On Thu, Aug 24, 2023 at 02:28:53PM +0200, Magnus Karlsson wrote:
> > > From: Magnus Karlsson <magnus.karlsson@intel.com>
> > >
> > > Introduce the XSKTEST_ETH environment variable to be able to set the
> > > network interface that should be used for testing.
> > >
> > > Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
> > > ---
> > >  tools/testing/selftests/bpf/test_xsk.sh | 20 +++++++++-----------
> > >  1 file changed, 9 insertions(+), 11 deletions(-)
> > >
> > > diff --git a/tools/testing/selftests/bpf/test_xsk.sh b/tools/testing/selftests/bpf/test_xsk.sh
> > > index 9ec718043c1a..3e0a2302a185 100755
> > > --- a/tools/testing/selftests/bpf/test_xsk.sh
> > > +++ b/tools/testing/selftests/bpf/test_xsk.sh
> > > @@ -88,14 +88,12 @@
> > >
> > >  . xsk_prereqs.sh
> > >
> > > -ETH=""
> > > -
> > >  while getopts "vi:dm:lt:h" flag
> > >  do
> > >       case "${flag}" in
> > >               v) verbose=1;;
> > >               d) debug=1;;
> > > -             i) ETH=${OPTARG};;
> > > +             i) XSKTEST_ETH=${OPTARG};;
> > >               m) XSKTEST_MODE=${OPTARG};;
> > >               l) list=1;;
> > >               t) XSKTEST_TEST=${OPTARG};;
> > > @@ -157,9 +155,9 @@ if [[ $help -eq 1 ]]; then
> > >          exit
> > >  fi
> > >
> > > -if [ ! -z $ETH ]; then
> > > -     VETH0=${ETH}
> > > -     VETH1=${ETH}
> > > +if [ -n "$XSKTEST_ETH" ]; then
> >
> > Sorry - is point of this patch is just to invert the logic and rename the
> > env var?
> 
> The purpose was to make it setable from the outside and give it a name
> that is more descriptive and targeted only to xskxceiver.

and this is accomplished by not having ETH initialized here? What will be
'the outside' ?

Currently I don't see much value within this patch, unless you explain the
need for setting this from outside of this script. Maybe I missed some
discussion from v1. I can live with this variable being ETH, what's more
concerning/confusing to me is that for ZC we have to set VETH0 and VETH1
to ETH and then use that later on.


> 
> > > +     VETH0=${XSKTEST_ETH}
> > > +     VETH1=${XSKTEST_ETH}
> > >  else
> > >       validate_root_exec
> > >       validate_veth_support ${VETH0}
> > > @@ -203,10 +201,10 @@ fi
> > >
> > >  exec_xskxceiver
> > >
> > > -if [ -z $ETH ]; then
> > > +if [ -z $XSKTEST_ETH ]; then
> > >       cleanup_exit ${VETH0} ${VETH1}
> > >  else
> > > -     cleanup_iface ${ETH} ${MTU}
> > > +     cleanup_iface ${XSKTEST_ETH} ${MTU}
> > >  fi
> > >
> > >  if [[ $list -eq 1 ]]; then
> > > @@ -216,17 +214,17 @@ fi
> > >  TEST_NAME="XSK_SELFTESTS_${VETH0}_BUSY_POLL"
> > >  busy_poll=1
> > >
> > > -if [ -z $ETH ]; then
> > > +if [ -z $XSKTEST_ETH ]; then
> > >       setup_vethPairs
> > >  fi
> > >  exec_xskxceiver
> > >
> > >  ## END TESTS
> > >
> > > -if [ -z $ETH ]; then
> > > +if [ -z $XSKTEST_ETH ]; then
> > >       cleanup_exit ${VETH0} ${VETH1}
> > >  else
> > > -     cleanup_iface ${ETH} ${MTU}
> > > +     cleanup_iface ${XSKTEST_ETH} ${MTU}
> > >  fi
> > >
> > >  failures=0
> > > --
> > > 2.34.1
> > >