6.6-stable review patch. If anyone has any objections, please let me know.
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From: Steven Rostedt rostedt@goodmis.org
commit dd4adb986a86727ed8f56c48b6d0695f1e211e65 upstream.
The tracing selftest "event-filter-function.tc" was failing because it first runs the "sample_events" function that triggers the kmem_cache_free event and it looks at what function was used during a call to "ls".
But the first time it calls this, it could trigger events that are used to pull pages into the page cache.
The rest of the test uses the function it finds during that call to see if it will be called in subsequent "sample_events" calls. But if there's no need to pull pages into the page cache, it will not trigger that function and the test will fail.
Call the "sample_events" twice to trigger all the page cache work before it calls it to find a function to use in subsequent checks.
Cc: stable@vger.kernel.org Fixes: eb50d0f250e96 ("selftests/ftrace: Choose target function for filter test from samples") Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Acked-by: Masami Hiramatsu (Google) mhiramat@kernel.org Signed-off-by: Shuah Khan skhan@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc | 4 ++++ 1 file changed, 4 insertions(+)
--- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc +++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc @@ -20,6 +20,10 @@ sample_events() { echo 0 > tracing_on echo 0 > events/enable
+# Clear functions caused by page cache; run sample_events twice +sample_events +sample_events + echo "Get the most frequently calling function" echo > trace sample_events