G-EDF: always mark scheduled tasks as being so (bugfix)

If schedule() was invoked twice in a retry, then the scheduled
task might have not been "picked" properly because it was
still scheduled.

1 files changed, 9 insertions, 2 deletions

diff --git a/litmus/sched_gedf.c b/litmus/sched_gedf.c
index 3e544bb159..5e139ae36b 100644
--- a/litmus/sched_gedf.c
+++ b/litmus/sched_gedf.c
@@ -134,7 +134,7 @@ static noinline void link_task_to_cpu(struct task_struct* linked,
         }
         entry->linked = linked;
         entry->picked = entry == sched; /* set to one if we linked to the
-                                         * the CPU that the task is 
+                                         * the CPU that the task is
                                          * executing on
                                          */
         if (linked)
@@ -425,7 +425,6 @@ static struct task_struct* gedf_schedule(struct task_struct * prev)
                 /* Schedule a linked job? */
                 if (entry->linked) {
                         entry->linked->rt_param.scheduled_on = entry->cpu;
-                        entry->picked = 1;
                         next = entry->linked;
                 }
                 if (entry->scheduled)
@@ -437,6 +436,14 @@ static struct task_struct* gedf_schedule(struct task_struct * prev)
                 if (exists)
                         next = prev;
 
+        /* Mark entry->linked as being ours.  Do this unconditionally since
+         * entry->linked might have become reassigned to us while we dropped
+         * the lock even though we never descheduled it. In this case,
+         * entry->picked became reset.
+         */
+        entry->picked = 1;
+        if (next)
+                tsk_rt(next)->scheduled_on = entry->cpu;
         spin_unlock(&gedf_cpu_lock);
         if (exists && preempt && !blocks)
                 /* stick preempted task back into the ready queue */