Refactor timer merging and add it to CE plugin.

THIS CODE IS UNTESTED

We now initialize one event group for each cpu on system start. We can
get the event group for a CPU via a function in event_group.c

Another change is that an event now stores what group it is in when it
add_event() is called on it. This lets us cancel it without knowing what
event group it is in.

The above is important because Level-C events (like releases) have a
NULL event group. When calling add_event(), it will get the event group
of the current CPU. If the event needs to be canceled later, we need
that saved group in the event so we know where to remove it from.

1 files changed, 7 insertions, 6 deletions

diff --git a/include/litmus/sched_mc.h b/include/litmus/sched_mc.h
index 95cc367c8ade..7088c0766db2 100644
--- a/include/litmus/sched_mc.h
+++ b/include/litmus/sched_mc.h
@@ -51,12 +51,12 @@ struct mc_data {
 struct ce_dom_data {
         int cpu;
         struct task_struct *scheduled, *should_schedule;
-        /*
-         * Each CPU needs a mapping of level A ID (integer) to struct pid so
-         * that we can get its task struct.
-         */
+#ifdef CONFIG_MERGE_TIMERS
+        struct rt_event event;
+#else
         struct hrtimer_start_on_info timer_info;
         struct hrtimer timer;
+#endif
 };
 
 /**
@@ -65,7 +65,8 @@ struct ce_dom_data {
  * @linked      Logically running task, ghost or regular
  * @domain      Domain from which to draw tasks
  * @usable      False if a higher criticality task is running
- * @timer       For ghost task budget enforcement
+ * @event       For ghost task budget enforcement (merge timers)
+ * @timer       For ghost task budget enforcement (not merge timers)
  * @node        Used to sort crit_entries by preemptability in global domains
  */
 struct crit_entry {
@@ -105,7 +106,7 @@ unsigned int mc_ce_get_expected_job(const int, const int);
  */
 long mc_ce_admit_task_common(struct task_struct*);
 void mc_ce_task_exit_common(struct task_struct*);
-void mc_ce_timer_callback_common(domain_t*, struct hrtimer*);
+lt_t mc_ce_timer_callback_common(domain_t*);
 void mc_ce_release_at_common(struct task_struct*, lt_t);
 long mc_ce_activate_plugin_common(void);
 long mc_ce_deactivate_plugin_common(void);