From: Steven Rostedt <srostedt@redhat.com>
Date: Wed, 14 Jan 2009 19:50:19 +0000 (-0500)
Subject: trace: stop all recording to ring buffer on ftrace_dump
X-Git-Tag: archive/raspbian/4.9.13-1+rpi1~10^2~22380^2~368
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/www.github.com/%22bookmarks:///%22http:/www.example.com/cgi/%22https:/www.github.com/%22bookmarks:/?a=commitdiff_plain;h=0ee6b6cf5bdb793b4c68507dd65adf16341aa4ca;p=linux-4.9.git

trace: stop all recording to ring buffer on ftrace_dump

Impact: limit ftrace dump output

Currently ftrace_dump only calls ftrace_kill that is a fast way
to prevent the function tracer functions from being called (just sets
a flag and clears the function to call, nothing else). It is better
to also turn off any recording to the ring buffers as well.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 408c03f2b8a9..dcb757f70d21 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3110,6 +3110,7 @@ void ftrace_dump(void)
 	dump_ran = 1;
 
 	/* No turning back! */
+	tracing_off();
 	ftrace_kill();
 
 	for_each_tracing_cpu(cpu) {