mac80211: trace debug messages

It can be very useful to have all debug messages
available when debugging, but hard to correlate
between different sources, so add a trace event
for all mac80211 debug messages.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/trace.h b/net/mac80211/trace.h
index 392bcc9..2e60f4a 100644
--- a/net/mac80211/trace.h
+++ b/net/mac80211/trace.h
@@ -1632,6 +1632,45 @@
 		LOCAL_PR_ARG, __entry->queue, __entry->reason
 	)
 );
+
+#ifdef CONFIG_MAC80211_MESSAGE_TRACING
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM mac80211_msg
+
+#define MAX_MSG_LEN	100
+
+DECLARE_EVENT_CLASS(mac80211_msg_event,
+	TP_PROTO(struct va_format *vaf),
+
+	TP_ARGS(vaf),
+
+	TP_STRUCT__entry(
+		__dynamic_array(char, msg, MAX_MSG_LEN)
+	),
+
+	TP_fast_assign(
+		WARN_ON_ONCE(vsnprintf(__get_dynamic_array(msg),
+				       MAX_MSG_LEN, vaf->fmt,
+				       *vaf->va) >= MAX_MSG_LEN);
+	),
+
+	TP_printk("%s", __get_str(msg))
+);
+
+DEFINE_EVENT(mac80211_msg_event, mac80211_info,
+	TP_PROTO(struct va_format *vaf),
+	TP_ARGS(vaf)
+);
+DEFINE_EVENT(mac80211_msg_event, mac80211_dbg,
+	TP_PROTO(struct va_format *vaf),
+	TP_ARGS(vaf)
+);
+DEFINE_EVENT(mac80211_msg_event, mac80211_err,
+	TP_PROTO(struct va_format *vaf),
+	TP_ARGS(vaf)
+);
+#endif
+
 #endif /* !__MAC80211_DRIVER_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH