selftests: ftrace: Add a testcase for types of kprobe event

Add a testcase for types of kprobe event. This checks
kprobe event can accept and correctly expressed the
arguments typed as s32, u32, x32 and bitfield.

Here is the test result.
  -----
  # ./ftracetest test.d/kprobe/kprobe_args_type.tc
  === Ftrace unit tests ===
  [1] Kprobes event arguments with types	[PASS]

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

Link: http://lkml.kernel.org/r/147928409063.22982.3499119203875115458.stgit@devbox

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

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

@@ -0,0 +1,37 @@
+#!/bin/sh
+# description: Kprobes event arguments with types
+
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
+grep "x8/16/32/64" README > /dev/null || exit_unsupported # version issue
+
+echo 0 > events/enable
+echo > kprobe_events
+enable_tracing
+
+echo 'p:testprobe _do_fork $stack0:s32 $stack0:u32 $stack0:x32 $stack0:b8@4/32' > kprobe_events
+grep testprobe kprobe_events
+test -d events/kprobes/testprobe
+
+echo 1 > events/kprobes/testprobe/enable
+( echo "forked")
+echo 0 > events/kprobes/testprobe/enable
+ARGS=`tail -n 1 trace | sed -e 's/.* arg1=\(.*\) arg2=\(.*\) arg3=\(.*\) arg4=\(.*\)/\1 \2 \3 \4/'`
+
+check_types() {
+  X1=`printf "%x" $1 | tail -c 8`
+  X2=`printf "%x" $2`
+  X3=`printf "%x" $3`
+  test $X1 = $X2
+  test $X2 = $X3
+  test 0x$X3 = $3
+
+  B4=`printf "%x" $4`
+  B3=`echo -n $X3 | tail -c 3 | head -c 2`
+  test $B3 = $B4
+}
+check_types $ARGS
+
+echo "-:testprobe" >> kprobe_events
+clear_trace
+test -d events/kprobes/testprobe && exit 1 || exit 0