selftests/ftrace: Update multiple kprobes test for powerpc

KPROBES_ON_FTRACE is only available on powerpc64le. Update comment to
clarify this.

Also, we should use an offset of 8 to ensure that the probe does not
fall on ftrace location. The current offset of 4 will fall before the
function local entry point and won't fire, while an offset of 12 or 16
will fall on ftrace location. Offset 8 is currently guaranteed to not be
the ftrace location.

Link: http://lkml.kernel.org/r/3d32e8fa076070e83527476fdfa3a747bb9a1a3a.1499453040.git.naveen.n.rao@linux.vnet.ibm.com
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
index f4d1ff785d67d0b62eb7941bef178e5b8c5c2ecc..2a1cb990874613c5ee9da2d371b95899d8eaa81a 100644 (file)
--- a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
@@ -2,10 +2,10 @@
 # description: Register/unregister many kprobe events
 
 # ftrace fentry skip size depends on the machine architecture.
-# Currently HAVE_KPROBES_ON_FTRACE defined on x86 and powerpc
+# Currently HAVE_KPROBES_ON_FTRACE defined on x86 and powerpc64le
 case `uname -m` in
   x86_64|i[3456]86) OFFS=5;;
-  ppc*) OFFS=4;;
+  ppc64le) OFFS=8;;
   *) OFFS=0;;
 esac