1 files changed, 28 insertions, 13 deletions

diff --git a/litmus/sched_psn_edf.c b/litmus/sched_psn_edf.c
index 0e1675d2e572..63fa6103882a 100644
--- a/litmus/sched_psn_edf.c
+++ b/litmus/sched_psn_edf.c
@@ -174,17 +174,25 @@ static void psnedf_tick(struct task_struct *t)
          */
         BUG_ON(is_realtime(t) && t != pedf->scheduled);
 
-        if (is_realtime(t) && budget_enforced(t) && budget_exhausted(t)) {
-                if (!is_np(t)) {
-                        litmus_reschedule_local();
-                        TRACE("psnedf_scheduler_tick: "
-                              "%d is preemptable "
-                              " => FORCE_RESCHED\n", t->pid);
-                } else if (is_user_np(t)) {
-                        TRACE("psnedf_scheduler_tick: "
-                              "%d is non-preemptable, "
-                              "preemption delayed.\n", t->pid);
-                        request_exit_np(t);
+        if (is_realtime(t) && budget_exhausted(t))
+        {
+                if (budget_signalled(t) && !sigbudget_sent(t)) {
+                        /* signal exhaustion */
+                        send_sigbudget(t);
+                }
+
+                if (budget_enforced(t)) {
+                        if (!is_np(t)) {
+                                litmus_reschedule_local();
+                                TRACE("psnedf_scheduler_tick: "
+                                          "%d is preemptable "
+                                          " => FORCE_RESCHED\n", t->pid);
+                        } else if (is_user_np(t)) {
+                                TRACE("psnedf_scheduler_tick: "
+                                          "%d is non-preemptable, "
+                                          "preemption delayed.\n", t->pid);
+                                request_exit_np(t);
+                        }
                 }
         }
 }
@@ -195,8 +203,7 @@ static struct task_struct* psnedf_schedule(struct task_struct * prev)
         rt_domain_t*            edf  = &pedf->domain;
         struct task_struct*     next;
 
-        int                     out_of_time, sleep, preempt,
-                                np, exists, blocks, resched;
+        int out_of_time, signal_budget, sleep, preempt, np, exists, blocks, resched;
 
         raw_spin_lock(&pedf->slock);
 
@@ -213,6 +220,10 @@ static struct task_struct* psnedf_schedule(struct task_struct * prev)
         out_of_time = exists &&
                                   budget_enforced(pedf->scheduled) &&
                                   budget_exhausted(pedf->scheduled);
+        signal_budget = exists &&
+                                        budget_signalled(pedf->scheduled) &&
+                                        budget_exhausted(pedf->scheduled) &&
+                                        !sigbudget_sent(pedf->scheduled);
         np          = exists && is_np(pedf->scheduled);
         sleep       = exists && is_completed(pedf->scheduled);
         preempt     = edf_preemption_needed(edf, prev);
@@ -223,6 +234,10 @@ static struct task_struct* psnedf_schedule(struct task_struct * prev)
          */
         resched = preempt;
 
+        /* Send the signal that the budget has been exhausted */
+        if (signal_budget)
+                send_sigbudget(pedf->scheduled);
+
         /* If a task blocks we have no choice but to reschedule.
          */
         if (blocks)