From: Steven Rostedt <rostedt@goodmis.org>
Date: Mon, 12 May 2008 19:20:58 +0000 (+0200)
Subject: ftrace: return EOF in trace_pipe on change of tracer
X-Git-Tag: v2.6.27-rc1~1102^2^2~1^2~55
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=845279972f1736c3463c9cebd1bad92a0a347176;p=karo-tx-linux.git

ftrace: return EOF in trace_pipe on change of tracer

Break out of while loop with EOF when the current_trace changes.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d141fc98f3a8..2af940433e96 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2253,6 +2253,9 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
 		if (signal_pending(current))
 			return -EINTR;
 
+		if (iter->trace != current_trace)
+			return 0;
+
 		/*
 		 * We block until we read something and tracing is disabled.
 		 * We still block if tracing is disabled, but we have never