Debugged ghosts in the MC scheduler for CE tasks.

1 files changed, 23 insertions, 12 deletions

diff --git a/litmus/sched_mc.c b/litmus/sched_mc.c
index 11ba10a54f4d..afba6e44716f 100644
--- a/litmus/sched_mc.c
+++ b/litmus/sched_mc.c
@@ -407,6 +407,7 @@ void mc_check_for_preempt(domain_t *dom)
                         preempt(dom, ce);
                         update_crit_levels(entry);
                 } else {
+                        TRACE("domain: %s NOT preempting\n", dom->name);
                         raw_spin_unlock(&entry->lock);
                 }
         }
@@ -545,27 +546,37 @@ static enum hrtimer_restart ce_timer_function(struct hrtimer *timer)
 
         TRACE("MC level-A timer callback for CPU %d\n", ce_data->cpu);
 
-        raw_spin_lock_irqsave(dom->lock, flags);
+        local_irq_save(flags);
+
+        raw_spin_lock(dom->lock);
 
         raw_spin_lock(&crit_cpu(ce)->lock);
         if (ce->linked &&
-                        ce->linked == ce_data->should_schedule &&
-                        is_ghost(ce->linked))
+            ce->linked == ce_data->should_schedule &&
+            is_ghost(ce->linked))
         {
-                update_ghost_time(ce->linked);
-                if (tsk_mc_data(ce->linked)->mc_job.ghost_budget == 0) {
-                        old_link = ce->linked;
-                        link_task_to_crit(ce, NULL);
-                }
+                old_link = ce->linked;
+                tsk_mc_data(ce->linked)->mc_job.ghost_budget = 0;
+                link_task_to_crit(ce, NULL);
         }
         raw_spin_unlock(&crit_cpu(ce)->lock);
 
-        if (NULL != old_link)
+        mc_ce_timer_callback_common(dom, timer);
+
+        /* job completion will check for preemptions by means of calling job
+         * arrival if the task is not blocked */
+        if (NULL != old_link) {
+                TRACE("   old_link " TS " so will call job completion\n", TA(old_link));
+                raw_spin_unlock(dom->lock);
                 job_completion(old_link, 0);
+        } else {
+                TRACE("   old_link was null, so will call check for preempt\n");
+                raw_spin_unlock(dom->lock);
+                mc_check_for_preempt(dom);
+        }
+
+        local_irq_restore(flags);
 
-        mc_ce_timer_callback_common(dom, timer);
-        mc_check_for_preempt(dom);
-        raw_spin_unlock_irqrestore(dom->lock, flags);
         return HRTIMER_RESTART;
 }