tracing/urgent: warn in case of ftrace_start_up inbalance



Prevent from further ftrace_start_up inbalances so that we avoid
future nop patching omissions with dynamic ftrace.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>

parent c85a17e2

kernel/trace/ftrace.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -1224,6 +1224,13 @@ static void ftrace_shutdown(int command)
		return;

		ftrace_start_up--;
		/*
		* Just warn in case of unbalance, no need to kill ftrace, it's not
		* critical but the ftrace_call callers may be never nopped again after
		* further ftrace uses.
		*/
		WARN_ON_ONCE(ftrace_start_up < 0);

		if (!ftrace_start_up)
		command \|= FTRACE_DISABLE_CALLS;