Feather-Trace: keep track of release latency

1 files changed, 20 insertions, 0 deletions

diff --git a/litmus/trace.c b/litmus/trace.c
index 1e916aa406b9..f0eb2c706488 100644
--- a/litmus/trace.c
+++ b/litmus/trace.c
@@ -61,6 +61,26 @@ feather_callback void save_timestamp_cpu(unsigned long event,
         __save_timestamp_cpu(event, TSK_UNKNOWN, cpu);
 }
 
+feather_callback void save_task_latency(unsigned long event,
+                                        unsigned long when_ptr)
+{
+        lt_t now = litmus_clock();
+        lt_t *when = (lt_t*) when_ptr;
+        unsigned int seq_no;
+        int cpu = raw_smp_processor_id();
+        struct timestamp *ts;
+
+        seq_no = fetch_and_inc((int *) &ts_seq_no);
+        if (ft_buffer_start_write(trace_ts_buf, (void**)  &ts)) {
+                ts->event     = event;
+                ts->timestamp = now - *when;
+                ts->seq_no    = seq_no;
+                ts->cpu       = cpu;
+                ts->task_type = TSK_RT;
+                ft_buffer_finish_write(trace_ts_buf, ts);
+        }
+}
+
 /******************************************************************************/
 /*                        DEVICE FILE DRIVER                                  */
 /******************************************************************************/