From 95100358491abaa2e9a5483811370059bbca4645 Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@intel.com>
Date: Thu, 24 Nov 2011 20:03:08 +0100
Subject: printk/tracing: Add console output tracing

Add a printk.console trace point to record any printk
messages into the trace, regardless of the current
console loglevel. This can help correlate (existing)
printk debugging with other tracing.

Link: http://lkml.kernel.org/r/1322161388.5366.54.camel@jlt3.sipsolutions.net

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/printk.c | 5 +++++
 1 file changed, 5 insertions(+)

(limited to 'kernel/printk.c')

diff --git a/kernel/printk.c b/kernel/printk.c
index 13c0a1143f4..cb8a6bd697c 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -44,6 +44,9 @@
 
 #include <asm/uaccess.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/printk.h>
+
 /*
  * Architectures can override it:
  */
@@ -542,6 +545,8 @@ MODULE_PARM_DESC(ignore_loglevel, "ignore loglevel setting, to"
 static void _call_console_drivers(unsigned start,
 				unsigned end, int msg_log_level)
 {
+	trace_console(&LOG_BUF(0), start, end, log_buf_len);
+
 	if ((msg_log_level < console_loglevel || ignore_loglevel) &&
 			console_drivers && start != end) {
 		if ((start & LOG_BUF_MASK) > (end & LOG_BUF_MASK)) {
-- 
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