LITMUS^RT core: keep track of time of last suspension

This information is needed to insert ST_COMPLETION records for
sporadic tasks.

2 files changed, 9 insertions, 0 deletions

diff --git a/include/litmus/rt_param.h b/include/litmus/rt_param.h
index 0070cbcbe21e..7663e0806531 100644
--- a/include/litmus/rt_param.h
+++ b/include/litmus/rt_param.h
@@ -155,6 +155,12 @@ struct rt_job {
          * Increase this sequence number when a job is released.
          */
         unsigned int    job_no;
+
+#ifdef CONFIG_SCHED_TASK_TRACE
+        /* Keep track of the last time the job suspended.
+         * -> used for tracing sporadic tasks. */
+        lt_t    last_suspension;
+#endif
 };
 
 struct pfair_param;
diff --git a/kernel/sched/litmus.c b/kernel/sched/litmus.c
index fdb17e958adb..979f0a946220 100644
--- a/kernel/sched/litmus.c
+++ b/kernel/sched/litmus.c
@@ -218,6 +218,9 @@ static void dequeue_task_litmus(struct rq *rq, struct task_struct *p,
                                 int flags)
 {
         if (flags & DEQUEUE_SLEEP) {
+#ifdef CONFIG_SCHED_TASK_TRACE
+                tsk_rt(p)->job_params.last_suspension = litmus_clock();
+#endif
                 litmus->task_block(p);
                 tsk_rt(p)->present = 0;
                 sched_trace_task_block(p);