Re: [PATCH v2 3/3] selftests/ftrace: Fix kprobe string testcase to not probe notrace function

From: Masami Hiramatsu <mhiramat@kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Francis Deslauriers <francis.deslauriers@efficios.com>,
	peterz@infradead.org, mathieu.desnoyers@efficios.com,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 3/3] selftests/ftrace: Fix kprobe string testcase to not probe notrace function
Date: Sat, 28 Jul 2018 08:59:22 +0900	[thread overview]
Message-ID: <20180728085922.bbc1ff641f27d59ae8c02ef2@kernel.org> (raw)
In-Reply-To: <20180727174307.33990e4f@gandalf.local.home>

On Fri, 27 Jul 2018 17:43:07 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Thu, 26 Jul 2018 14:54:23 +0900
> Masami Hiramatsu <mhiramat@kernel.org> wrote:
> 
> > Fix kprobe string argument testcase to not probe notrace
> > function. Instead, it probes tracefs function which must
> > be available with ftrace.
> 
> Hi Masami,
> 
> With these patches applied, this test fails:
> 
>  ./ftracetest  test.d/kprobe/probepoint.tc
> 
> Gives me the error in dmseg:
> 
>   trace_kprobe: Could not probe notrace function create_trace_kprobe
> 
> Is this expected? I don't see create_trace_kprobe as a notrace function
> either.
> 
> I even applied patch 3 (going through Shuah's tree) to me test and it
> still fails.

Oops, why I missed this...
OK, I'll fix it.

Thanks,

> 
> Config attached.
> 
> -- Steve
> 
> > 
> > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> > ---
> >  .../ftrace/test.d/kprobe/kprobe_args_string.tc     |   30 ++++++++------------
> >  1 file changed, 12 insertions(+), 18 deletions(-)
> > 
> > diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc
> > index a0002563e9ee..1ad70cdaf442 100644
> > --- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc
> > +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc
> > @@ -9,28 +9,22 @@ echo > kprobe_events
> >  
> >  case `uname -m` in
> >  x86_64)
> > -  ARG2=%si
> > -  OFFS=8
> > +  ARG1=%di
> >  ;;
> >  i[3456]86)
> > -  ARG2=%cx
> > -  OFFS=4
> > +  ARG1=%ax
> >  ;;
> >  aarch64)
> > -  ARG2=%x1
> > -  OFFS=8
> > +  ARG1=%x0
> >  ;;
> >  arm*)
> > -  ARG2=%r1
> > -  OFFS=4
> > +  ARG1=%r0
> >  ;;
> >  ppc64*)
> > -  ARG2=%r4
> > -  OFFS=8
> > +  ARG1=%r3
> >  ;;
> >  ppc*)
> > -  ARG2=%r4
> > -  OFFS=4
> > +  ARG1=%r3
> >  ;;
> >  *)
> >    echo "Please implement other architecture here"
> > @@ -38,17 +32,17 @@ ppc*)
> >  esac
> >  
> >  : "Test get argument (1)"
> > -echo "p:testprobe create_trace_kprobe arg1=+0(+0(${ARG2})):string" > kprobe_events
> > +echo "p:testprobe tracefs_create_dir arg1=+0(${ARG1}):string" > kprobe_events
> >  echo 1 > events/kprobes/testprobe/enable
> > -! echo test >> kprobe_events
> > -tail -n 1 trace | grep -qe "testprobe.* arg1=\"test\""
> > +echo "p:test _do_fork" >> kprobe_events
> > +grep -qe "testprobe.* arg1=\"test\"" trace
> >  
> >  echo 0 > events/kprobes/testprobe/enable
> >  : "Test get argument (2)"
> > -echo "p:testprobe create_trace_kprobe arg1=+0(+0(${ARG2})):string arg2=+0(+${OFFS}(${ARG2})):string" > kprobe_events
> > +echo "p:testprobe tracefs_create_dir arg1=+0(${ARG1}):string arg2=+0(${ARG1}):string" > kprobe_events
> >  echo 1 > events/kprobes/testprobe/enable
> > -! echo test1 test2 >> kprobe_events
> > -tail -n 1 trace | grep -qe "testprobe.* arg1=\"test1\" arg2=\"test2\""
> > +echo "p:test _do_fork" >> kprobe_events
> > +grep -qe "testprobe.* arg1=\"test\" arg2=\"test\"" trace
> >  
> >  echo 0 > events/enable
> >  echo > kprobe_events
> 

-- 
Masami Hiramatsu <mhiramat@kernel.org>