Force rescheduling if a task leaves a np section is not linked.

1 files changed, 15 insertions, 5 deletions

diff --git a/kernel/sched_gsn_edf.c b/kernel/sched_gsn_edf.c
index c1e3b7b8d0..b8cc48e584 100644
--- a/kernel/sched_gsn_edf.c
+++ b/kernel/sched_gsn_edf.c
@@ -341,7 +341,8 @@ static long gsnedf_prepare_task(struct task_struct * t)
         if (t->state == TASK_STOPPED) {
                 __setscheduler(t, SCHED_FIFO, MAX_RT_PRIO - 1);
 
-                t->rt_param.scheduled_on = NO_CPU;
+                t->rt_param.scheduled_on       = NO_CPU;
+                t->rt_param.is_non_preemptable = 0;
                 if (get_rt_mode() == MODE_RT_RUN)
                         /* The action is already on. 
                          * Prepare immediate release
@@ -377,7 +378,9 @@ static void gsnedf_wake_up_task(struct task_struct *task)
         task->state = TASK_RUNNING;
 
         /* FIXME: We need to take suspensions because of semaphores into
-         *        account! */
+         *        account! If a job resumes after being suspended due to acquiring
+         *        a semaphore, it should never be treated as a new job release.
+         */
         if (is_tardy(task)) {
                 /* new sporadic release */
                 prepare_new_release(task);
@@ -431,11 +434,18 @@ static long gsnedf_exit_np(struct task_struct * t)
 {
         unsigned long           flags;
         int ret = 0;
+        cpu_entry_t *entry;
 
         queue_lock_irqsave(&gsnedf_lock, flags);
-        if (is_np(t))
+        if (is_np(t)) {
                 t->rt_param.is_non_preemptable--;
-        else 
+                entry = &__get_cpu_var(gsnedf_cpu_entries);
+                if (!is_np(t) && entry->linked != t) {
+                        /* t is now preemptable and not linked */
+                        BUG_ON(t != entry->scheduled);                  
+                        set_tsk_need_resched(current);
+                }
+        } else 
                 ret = -EPERM;
         queue_unlock_irqrestore(&gsnedf_lock, flags);
         return ret;
@@ -499,7 +509,7 @@ static sched_plugin_t s_plugin __cacheline_aligned_in_smp = {
         .task_blocks            = gsnedf_task_blocks, \
         .enter_np               = gsnedf_enter_np, \
         .exit_np                = gsnedf_exit_np \
-        }
+}
 
 
 sched_plugin_t *__init init_gsn_edf_plugin(void)