[PATCH 3.4 10/22] tracing: Remove ftrace_stop/start() from reading the trace file

Greg Kroah-Hartman
2014-07-16T00:20:42Z

From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>

commit 099ed151675cd1d2dbeae1dac697975f6a68716d upstream.

Disabling reading and writing to the trace file should not be able to
disable all function tracing callbacks. There's other users today
(like kprobes and perf). Reading a trace file should not stop those
from happening.

Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
kernel/trace/trace.c | 2 --
1 file changed, 2 deletions(-)

--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1052,7 +1052,6 @@ void tracing_start(void)

arch_spin_unlock(&ftrace_max_lock);

- ftrace_start();
out:
raw_spin_unlock_irqrestore(&tracing_start_lock, flags);
}
@@ -1068,7 +1067,6 @@ void tracing_stop(void)
struct ring_buffer *buffer;
unsigned long flags;

- ftrace_stop();
raw_spin_lock_irqsave(&tracing_start_lock, flags);
if (trace_stop_count++)
goto out;