score: Remove PRIORITY_PSEUDO_ISR thread priority

The uniprocessor schedulers had some special case logic for the
PRIORITY_PSEUDO_ISR priority.  Tasks with a priority of PRIORITY_PSEUDO_ISR
were allowed to preempt a not preemptible task.  If other higher priority task
are made ready while a PRIORITY_PSEUDO_ISR task preempts a not preemptible
task, then the other tasks run before the not preemptible task.  This made the
RTEMS_NO_PREEMPT mode ineffective.

Remove the PRIORITY_PSEUDO_ISR special case logic.  This simplifies the
uniprocessor schedulers.  Move the uniprocessor-specific scheduler support to
the new header file <rtems/score/scheduleruniimpl.h>.

Close #2365.

1 files changed, 1 insertions, 15 deletions

diff --git a/cpukit/score/src/schedulerpriorityunblock.c b/cpukit/score/src/schedulerpriorityunblock.c
index 190c126908..f9b6cabff7 100644
--- a/cpukit/score/src/schedulerpriorityunblock.c
+++ b/cpukit/score/src/schedulerpriorityunblock.c
@@ -76,19 +76,5 @@ void _Scheduler_priority_Unblock (
 
   /* TODO: flash critical section? */
 
-  /*
-   *  If the thread that was unblocked is more important than the heir,
-   *  then we have a new heir.  This may or may not result in a
-   *  context switch.
-   *
-   *  Normal case:
-   *    If the current thread is preemptible, then we need to do
-   *    a context switch.
-   *  Pseudo-ISR case:
-   *    Even if the thread isn't preemptible, if the new heir is
-   *    a pseudo-ISR system task, we need to do a context switch.
-   */
-  if ( priority < _Thread_Get_priority( _Thread_Heir ) ) {
-    _Scheduler_Update_heir( the_thread, priority == PRIORITY_PSEUDO_ISR );
-  }
+  _Scheduler_uniprocessor_Unblock( scheduler, the_thread, priority );
 }