Re: [PATCH v15 15/15] tracing: Add hist trigger action 'expected fail' test case

[Tom Zanussi <zanussi@kernel.org>]

Hi Steve,

On Wed, 2019-02-20 at 12:56 -0500, Steven Rostedt wrote:
> On Wed, 20 Feb 2019 11:38:22 -0600
> Tom Zanussi <zanussi@kernel.org> wrote:
> 
> > Hi Steve,
> > 
> > On Wed, 2019-02-20 at 12:17 -0500, Steven Rostedt wrote:
> > > On Wed, 13 Feb 2019 17:42:55 -0600
> > > Tom Zanussi <zanussi@kernel.org> wrote:
> > >   
> > > > From: Tom Zanussi <tom.zanussi@linux.intel.com>
> > > > 
> > > > Add a test case verifying that basic action combinations fail
> > > > as
> > > > expected.
> > > >   
> > > 
> > > Hi Tom,
> > > 
> > > This test appears to fail:
> > > 
> > > # echo
> > > 'hist:keys=comm:onmatch(sched.sched_wakeup).save(comm,prio)'  
> > > > > /sys/kernel/debug/tracing/events/sched/sched_waking/trigger  
> > > 
> > > -bash: echo: write error: Invalid argument
> > > 
> > > # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist 
> > > 
> > > ERROR: action parsing: Handler doesn't support action: save
> > >   Last command:
> > > keys=comm:onmatch(sched.sched_wakeup).save(comm,prio)
> > > 
> > > 
> > > Is the "save" feature implemented here? It's in the README too.
> > > Should
> > > it be removed?
> > >   
> > 
> > The "save" feature is implemented, but it's not currently supported
> > with onmatch(), which is why it fails, and is used in the xfail
> > test,
> > since it's expected to.  So, in this case, the command fails, which
> > means the xfail test actually passed.  ;-)
> > 
> > There are other tests in the inter-event testcases that use save()
> > but
> > with onmax() and onchange(), and they pass.
> 
> So the test needs to pass on failure?
> 
> Because, it shouldn't be flagged as a failure in the test suite.
> 

As far as I understand it (there's no other case of an xfail test in
the testsuite, so nothing similar to compare it to), the test output is
 correct - here we get the expected fail, XFAIL, and not a FAIL as any
test, xfail or normal, that failed would produce:

tools/testing/selftests/ftrace# ./ftracetest test.d/trigger/
=== Ftrace unit tests ===
[1] event trigger - test inter-event histogram trigger expected fail actions
[XFAIL]
[2] event trigger - test extended error support
[PASS]

And here the summary shows none failed, while we did have one expected
xfail, but that's what was expected, and not a failure:

# of passed:  31
# of failed:  0
# of unresolved:  0
# of untested:  0
# of unsupported:  0
# of xfailed:  1
# of undefined(test bug):  0

If that's not correct, I'll fix it but at this point I'm not sure what
the output should be if not that.

Thanks,

Tom

> -- Steve
> 
> > 
> > Hope that explains things in this case,
> > 
> > Tom
> > 
> > > -- Steve
> > >   
> > > > Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
> > > > ---
> > > >  .../inter-event/trigger-action-hist-xfail.tc       | 30
> > > > ++++++++++++++++++++++
> > > >  1 file changed, 30 insertions(+)
> > > >  create mode 100644
> > > > tools/testing/selftests/ftrace/test.d/trigger/inter-
> > > > event/trigger-
> > > > action-hist-xfail.tc
> > > > 
> > > > diff --git
> > > > a/tools/testing/selftests/ftrace/test.d/trigger/inter-
> > > > event/trigger-action-hist-xfail.tc
> > > > b/tools/testing/selftests/ftrace/test.d/trigger/inter-
> > > > event/trigger-action-hist-xfail.tc
> > > > new file mode 100644
> > > > index 000000000000..1221240f8cf6
> > > > --- /dev/null
> > > > +++ b/tools/testing/selftests/ftrace/test.d/trigger/inter-
> > > > event/trigger-action-hist-xfail.tc
> > > > @@ -0,0 +1,30 @@
> > > > +#!/bin/sh
> > > > +# SPDX-License-Identifier: GPL-2.0
> > > > +# description: event trigger - test inter-event histogram
> > > > trigger
> > > > expected fail actions
> > > > +
> > > > +fail() { #msg
> > > > +    echo $1
> > > > +    exit_fail
> > > > +}
> > > > +
> > > > +if [ ! -f set_event ]; then
> > > > +    echo "event tracing is not supported"
> > > > +    exit_unsupported
> > > > +fi
> > > > +
> > > > +if [ ! -f snapshot ]; then
> > > > +    echo "snapshot is not supported"
> > > > +    exit_unsupported
> > > > +fi
> > > > +
> > > > +grep -q "snapshot()" README || exit_unsupported # version
> > > > issue
> > > > +
> > > > +echo "Test expected snapshot action failure"
> > > > +
> > > > +echo 'hist:keys=comm:onmatch(sched.sched_wakeup).snapshot()'
> > > > >>
> > > > /sys/kernel/debug/tracing/events/sched/sched_waking/trigger &&
> > > > exit_fail
> > > > +
> > > > +echo "Test expected save action failure"
> > > > +
> > > > +echo
> > > > 'hist:keys=comm:onmatch(sched.sched_wakeup).save(comm,prio)'  
> > > > > > /sys/kernel/debug/tracing/events/sched/sched_waking/trigger
> > > > > > &&  
> > > > 
> > > > exit_fail
> > > > +
> > > > +exit_xfail  
> > > 
> > >   
> 
>