EDF-WM: migrating tasks can actually be queued when blocking

The migration code patch simulates blocking if state changes occur
while dropping the lock. We need to handle that.

1 files changed, 10 insertions, 2 deletions

diff --git a/litmus/sched_edf_wm.c b/litmus/sched_edf_wm.c
index f3627ad1174a..44e05948980c 100644
--- a/litmus/sched_edf_wm.c
+++ b/litmus/sched_edf_wm.c
@@ -505,14 +505,22 @@ static void wm_task_wake_up(struct task_struct *t)
 
 static void wm_task_block(struct task_struct *t)
 {
+        wm_domain_t* dom = domain_of_task(t);
+        unsigned long flags;
         lt_t now = litmus_clock();
-        /* only running tasks can block, thus t is in no queue */
+
         TRACE_TASK(t, "block at %llu, state=%d\n", now, t->state);
 
         tsk_rt(t)->semi_part.wm.suspend_time = now;
 
+        raw_spin_lock_irqsave(&dom->slock, flags);
+        if (is_queued(t)) {
+                TRACE_TASK(t, "still queued; migration invariant failed?\n");
+                remove(&dom->domain, t);
+        }
+        raw_spin_unlock_irqrestore(&dom->slock, flags);
+
         BUG_ON(!is_realtime(t));
-        BUG_ON(is_queued(t));
 }
 
 static void wm_task_exit(struct task_struct * t)