PGM support in GSN-EDF.

Patch enables PGM support by GSN-EDF. GSN-EDF boosts the priority
of a job waiting for inbound tokens. Likewise, boosting is removed
when inbound tokens have been received.

1 files changed, 40 insertions, 1 deletions

diff --git a/litmus/sched_gsn_edf.c b/litmus/sched_gsn_edf.c
index 34e6cff9753e..b819b62915f1 100644
--- a/litmus/sched_gsn_edf.c
+++ b/litmus/sched_gsn_edf.c
@@ -28,10 +28,13 @@
 #ifdef CONFIG_SCHED_CPU_AFFINITY
 #include <litmus/affinity.h>
 #endif
-
 /* to set up domain/cpu mappings */
 #include <litmus/litmus_proc.h>
 
+#ifdef CONFIG_SCHED_PGM
+#include <litmus/pgm.h>
+#endif
+
 #include <linux/module.h>
 
 /* Overview of GSN-EDF operations.
@@ -461,6 +464,42 @@ static struct task_struct* gsnedf_schedule(struct task_struct * prev)
                 TRACE_TASK(prev, "will be preempted by %s/%d\n",
                            entry->linked->comm, entry->linked->pid);
 
+#ifdef CONFIG_SCHED_PGM
+        if (exists && is_pgm_waiting(entry->scheduled)) {
+                if (!is_priority_boosted(entry->scheduled)) {
+                        TRACE_TASK(entry->scheduled, "is waiting for PGM tokens.\n");
+                        BUG_ON(is_pgm_satisfied(entry->scheduled));
+
+                        /* Boost priority so we'll be scheduled immediately
+                           when needed tokens arrive. */
+                        tsk_rt(entry->scheduled)->priority_boosted = 1;
+                        tsk_rt(entry->scheduled)->boost_start_time = litmus_clock();
+
+                        if (unlikely(!blocks)) {
+                                /* Task has probably blocked on an inbound token socket, but
+                                   if not, re-evaluate scheduling decisions */
+                                unlink(entry->scheduled);
+                                gsnedf_job_arrival(entry->scheduled);
+                        }
+                }
+                else if (is_pgm_satisfied(entry->scheduled)) {
+                        TRACE_TASK(entry->scheduled, "is done waiting for PGM tokens.\n");
+                        BUG_ON(!is_priority_boosted(entry->scheduled));
+
+                        /* clear any boosting */
+                        tsk_rt(entry->scheduled)->priority_boosted = 0;
+                        setup_pgm_release(entry->scheduled);
+
+                        if (likely(!blocks)) {
+                                /* Task has probably called sched_yield(), so blocking is
+                                   unlikely. Re-evaluate scheduling decisions because we
+                                   still want to run. */
+                                unlink(entry->scheduled);
+                                gsnedf_job_arrival(entry->scheduled);
+                        }
+                }
+        }
+#endif
 
         /* If a task blocks we have no choice but to reschedule.
          */