From: Masami Hiramatsu <mhiramat@kernel.org>
Date: Thu, 30 Aug 2018 14:21:53 +0000 (+0900)
Subject: selftests/ftrace: Add ringbuffer size changing testcase
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c21ceceae94dc22f5b42c8174efa4597a0c990de;p=linux.git

selftests/ftrace: Add ringbuffer size changing testcase

Add a testcase for changing ringbuffer size. This tests
not only ringbuffer size but also tests the imbalance
per-cpu buffer size change too.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>
---

diff --git a/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_size.tc b/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_size.tc
new file mode 100644
index 0000000000000..ab70f0077c35a
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_size.tc
@@ -0,0 +1,22 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Change the ringbuffer size
+# flags: instance
+
+rb_size_test() {
+ORIG=`cat buffer_size_kb`
+
+expr $ORIG / 2 > buffer_size_kb
+
+expr $ORIG \* 2 > buffer_size_kb
+
+echo $ORIG > buffer_size_kb
+}
+
+rb_size_test
+
+: "If per-cpu buffer is supported, imbalance it"
+if [ -d per_cpu/cpu0 ]; then
+  cd per_cpu/cpu0
+  rb_size_test
+fi