1 files changed, 18 insertions, 1 deletions

diff --git a/include/litmus/rt_param.h b/include/litmus/rt_param.h
index 5b94d1a8eea7..31630d729dbb 100644
--- a/include/litmus/rt_param.h
+++ b/include/litmus/rt_param.h
@@ -50,13 +50,26 @@ struct rt_task {
  * determining preemption/migration overheads).
  */
 struct control_page {
+        /* preemption and migration overheads measurement*/
+        /* execution start time */
+        lt_t preempt_end;
+        /* increased if last_rt != current */
+        unsigned long sched_count;
+        unsigned int cpu;
+        /* job number for this task */
+        unsigned long job_count;
+        /* last rt task before current one */
+        unsigned long last_rt_task;
+        /* execution stop time */
+        lt_t preempt_start;
+
         /* Is the task currently in a non-preemptive section? */
         int np_flag;
         /* Should the task call into the kernel when it leaves
          * its non-preemptive section? */
         int delayed_preemption;
 
-        /* to be extended */
+        /* what do you want to share today ? */
 };
 
 /* don't export internal data structures to user space (liblitmus) */
@@ -175,6 +188,10 @@ struct rt_param {
          */
         struct list_head list;
 
+        /* FIXME for overhead tracing it would be better
+         * having this page on top of rt_param and having rt_param
+         * closer to the top of task_struct
+         */
         /* Pointer to the page shared between userspace and kernel. */
         struct control_page * ctrl_page;
 };