On Wed, Sep 23, 2020 at 7:26 PM <bimmy.pujari@xxxxxxxxx> wrote: > > From: Bimmy Pujari <bimmy.pujari@xxxxxxxxx> > > Test xdping measures RTT from xdp using monotonic time helper. > Extending xdping test to use real time helper function in order > to verify this helper function. > > Signed-off-by: Bimmy Pujari <bimmy.pujari@xxxxxxxxx> > --- This is exactly the use of REALTIME clock that I was arguing against, and yet you are actually creating an example of how to use it for such case. CLOCK_REALTIME should not be used to measuring time elapsed (not within the same machine, at least), there are strictly better alternatives. So if you want to write a test for a new helper (assuming everyone else thinks it's a good idea), then do just that - write a separate minimal test that tests just your new functionality. Don't couple it with a massive XDP program. And also don't create unnecessarily almost 400 lines of code churn. > .../testing/selftests/bpf/progs/xdping_kern.c | 183 +---------------- > .../testing/selftests/bpf/progs/xdping_kern.h | 193 ++++++++++++++++++ > .../bpf/progs/xdping_realtime_kern.c | 4 + > tools/testing/selftests/bpf/test_xdping.sh | 44 +++- > 4 files changed, 235 insertions(+), 189 deletions(-) > create mode 100644 tools/testing/selftests/bpf/progs/xdping_kern.h > create mode 100644 tools/testing/selftests/bpf/progs/xdping_realtime_kern.c > [...]
