Re: [PATCH v4 7/8] tracing/selftests: Add tests for hist trigger expression parsing

On Tue, 26 Oct 2021 21:43:11 +0900
Masami Hiramatsu [off-list ref] wrote:

quoted

diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-expressions.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-expressions.tc
new file mode 100644
index 000000000000..e715641c54d3
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-expressions.tc

@@ -0,0 +1,72 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: event trigger - test histogram expression parsing
+# requires: set_event events/sched/sched_process_fork/trigger events/sched/sched_process_fork/hist error_log  

Hmm, are there any way to check the running kernel supports this feature?
Because the latest version of the kselftest is expected to run on the old stable
kernel for testing, the testcase should check whether the kernel supports this
testing feature or not. (That's why the requires tag supports README pattern check)

So, at first if you didn't update the <tracefs>/README, please update it first
to show the new syntax is supported, and add "SOME-PATTERN":README to the
requires tag.

Yes, please update the README in kernel/trace/trace.c readme_msg[].

I'll look at the other patches, and if they are fine, I may just apply them.

-- Steve