From 9ea1a153a4fb435c22e9988784bb476671286112 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Sat, 20 Jun 2009 06:52:21 +0200 Subject: [PATCH] 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 Cc: Steven Rostedt --- kernel/trace/ftrace.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index bb60732ade0c..3718d55fb4c3 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -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; -- 2.39.2