selftests/ftrace: Fix kprobe string testcase to not probe notrace function

Fix kprobe string argument testcase to not probe notrace
function. Instead, it probes tracefs function which must
be available with ftrace.

Link: http://lkml.kernel.org/r/153294607107.32740.1664854684396589624.stgit@devbox

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

Author: mhiramat

tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc

@@ -9,46 +9,40 @@ 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"
   exit_untested
 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

tools/testing/selftests/ftrace/test.d/kprobe/probepoint.tc

@@ -4,7 +4,7 @@
 
 [ -f kprobe_events ] || exit_unsupported # this is configurable
 
-TARGET_FUNC=create_trace_kprobe
+TARGET_FUNC=tracefs_create_dir
 
 dec_addr() { # hexaddr
   printf "%d" "0x"`echo $1 | tail -c 8`