[for-next][PATCH 2/4] selftests/ftrace: Update multiple kprobes test for powerpc

From: Steven Rostedt
Date: Mon Jul 10 2017 - 06:18:46 EST

From: "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxxxxxxx>

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@xxxxxxxxxxxxxxxxxx

Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

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 f4d1ff785d67..2a1cb9908746 100644
--- 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;;