Feather-Trace: Add macros for message-passing timestamps

Add timestamp tracing macros that reverse on which cores the
timestamps are recorded. This intended to reduce tracing contention if
some cores receive a lot of messages.

These macros are useful for plugins based on message-passing such as
the (non-mainline) G-EDF-MP.

2 files changed, 28 insertions, 6 deletions

diff --git a/include/litmus/trace.h b/include/litmus/trace.h
index 8ac4bb41a707..2646136e3881 100644
--- a/include/litmus/trace.h
+++ b/include/litmus/trace.h
@@ -28,14 +28,23 @@ struct timestamp {
 };
 
 /* tracing callbacks */
-feather_callback void msg_sent(unsigned long event, unsigned long to);
-feather_callback void msg_received(unsigned long event);
+feather_callback void msg_sent_to(unsigned long event, unsigned long to);
+feather_callback void msg_received_local(unsigned long event);
+
+feather_callback void msg_sent_local(unsigned long event);
+feather_callback void msg_received_from(unsigned long event, unsigned long from);
 
 #define MSG_TIMESTAMP_SENT(id, to) \
-        ft_event1(id, msg_sent, (unsigned long) to);
+        ft_event1(id, msg_sent_to, (unsigned long) (to));
 
 #define MSG_TIMESTAMP_RECEIVED(id) \
-        ft_event0(id, msg_received);
+        ft_event0(id, msg_received_local);
+
+#define MSG_TIMESTAMP_SENT_LOCAL(id) \
+        ft_event0(id, msg_sent_local);
+
+#define MSG_TIMESTAMP_RECEIVED_FROM(id, from) \
+        ft_event1(id, msg_received_from, (unsigned long) (from))
 
 feather_callback void save_cpu_timestamp(unsigned long event);
 feather_callback void save_cpu_timestamp_time(unsigned long event, unsigned long time_ptr);
diff --git a/litmus/trace.c b/litmus/trace.c
index 330d1e8240be..99846039286e 100644
--- a/litmus/trace.c
+++ b/litmus/trace.c
@@ -270,18 +270,31 @@ feather_callback void save_cpu_task_latency(unsigned long event,
                             now - *when, DO_NOT_RECORD_TIMESTAMP);
 }
 
-feather_callback void msg_sent(unsigned long event, unsigned long to)
+/* Record to remote trace buffer */
+feather_callback void msg_sent_to(unsigned long event, unsigned long to)
 {
         save_remote_msg_timestamp(event, to);
 }
 
+/* Record to local trace buffer */
+feather_callback void msg_sent_local(unsigned long event)
+{
+        save_msg_timestamp(event, 0);
+}
+
 /* Suppresses one IRQ from the irq count. Used by TS_SEND_RESCHED_END, which is
  * called from within an interrupt that is expected. */
-feather_callback void msg_received(unsigned long event)
+feather_callback void msg_received_local(unsigned long event)
 {
         save_msg_timestamp(event, 1);
 }
 
+/* Record to remote trace buffer */
+feather_callback void msg_received_from(unsigned long event, unsigned long from)
+{
+        save_remote_msg_timestamp(event, from);
+}
+
 static void __add_timestamp_user(struct timestamp *pre_recorded)
 {
         unsigned long flags;