[RFC PATCH 11/22 -v2] Reset the tracer when started

[Steven Rostedt <rostedt@goodmis.org>]

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This patch resets the trace when it is started by the user.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 lib/tracing/tracer.c |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

Index: linux-compile-i386.git/lib/tracing/tracer.c
===================================================================
--- linux-compile-i386.git.orig/lib/tracing/tracer.c	2008-01-09 14:14:02.000000000 -0500
+++ linux-compile-i386.git/lib/tracing/tracer.c	2008-01-09 15:17:36.000000000 -0500
@@ -78,6 +78,16 @@ static notrace void trace_function(const
 	raw_local_irq_restore(flags);
 }
 
+static notrace void mctracer_reset(struct mctracer_trace *tr)
+{
+	int cpu;
+
+	for_each_online_cpu(cpu) {
+		tr->trace_idx[cpu] = 0;
+		atomic_set(&tr->underrun[cpu], 0);
+	}
+}
+
 #ifdef CONFIG_DEBUG_FS
 enum trace_iterator {
 	TRACE_ITER_SYM_ONLY	= 1,
@@ -324,6 +334,10 @@ static ssize_t mctracer_ctrl_write(struc
 
 	val = !!simple_strtoul(buf, NULL, 10);
 
+	/* When starting a new trace, reset the buffers */
+	if (val)
+		mctracer_reset(tr);
+
 	if (tr->ctrl ^ val) {
 		if (val)
 			register_mcount_function(trace_function);

--