4.4-stable review patch. If anyone has any objections, please let me know.

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From: Masami Hiramatsu mhiramat@kernel.org

[ Upstream commit 82f4f3e69c5c29bce940dd87a2c0f16c51d48d17 ]

Add a testcase for checking snapshot and tracing_on relationship. This ensures that the snapshotting doesn't affect current tracing on/off settings.

Link: http://lkml.kernel.org/r/153149932412.11274.15289227592627901488.stgit@devbo...

Cc: Tom Zanussi tom.zanussi@linux.intel.com Cc: Hiraku Toyooka hiraku.toyooka@cybertrust.co.jp Signed-off-by: Masami Hiramatsu mhiramat@kernel.org Cc: Ingo Molnar mingo@redhat.com Cc: Shuah Khan shuah@kernel.org Cc: linux-kselftest@vger.kernel.org Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/testing/selftests/ftrace/test.d/00basic/snapshot.tc | 28 ++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 tools/testing/selftests/ftrace/test.d/00basic/snapshot.tc

--- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/00basic/snapshot.tc @@ -0,0 +1,28 @@ +#!/bin/sh +# description: Snapshot and tracing setting +# flags: instance + +[ ! -f snapshot ] && exit_unsupported + +echo "Set tracing off" +echo 0 > tracing_on + +echo "Allocate and take a snapshot" +echo 1 > snapshot + +# Since trace buffer is empty, snapshot is also empty, but allocated +grep -q "Snapshot is allocated" snapshot + +echo "Ensure keep tracing off" +test `cat tracing_on` -eq 0 + +echo "Set tracing on" +echo 1 > tracing_on + +echo "Take a snapshot again" +echo 1 > snapshot + +echo "Ensure keep tracing on" +test `cat tracing_on` -eq 1 + +exit 0