score: Fix _Thread_queue_Flush_critical()

The thread queue extract operations performed by the
_Thread_queue_Flush_critical() may result in a priority change of the
thread queue owner. Carry out the scheduler priority update operation.
This is especially important in SMP configurations.

Close #3236.

1 files changed, 14 insertions, 4 deletions

diff --git a/cpukit/score/src/threadqflush.c b/cpukit/score/src/threadqflush.c
index 8135e67b62..ef4d6b1f09 100644
--- a/cpukit/score/src/threadqflush.c
+++ b/cpukit/score/src/threadqflush.c
@@ -66,13 +66,15 @@ size_t _Thread_queue_Flush_critical(
   Thread_queue_Context          *queue_context
 )
 {
-  size_t         flushed;
-  Chain_Control  unblock;
-  Chain_Node    *node;
-  Chain_Node    *tail;
+  size_t          flushed;
+  Chain_Control   unblock;
+  Thread_Control *owner;
+  Chain_Node     *node;
+  Chain_Node     *tail;
 
   flushed = 0;
   _Chain_Initialize_empty( &unblock );
+  owner = queue->owner;
 
   while ( true ) {
     Thread_queue_Heads *heads;
@@ -131,6 +133,14 @@ size_t _Thread_queue_Flush_critical(
       node = next;
     } while ( node != tail );
 
+    if ( owner != NULL ) {
+      ISR_lock_Context lock_context;
+
+      _Thread_State_acquire( owner, &lock_context );
+      _Scheduler_Update_priority( owner );
+      _Thread_State_release( owner, &lock_context );
+    }
+
     _Thread_Dispatch_enable( cpu_self );
   } else {
     _Thread_queue_Queue_release( queue, &queue_context->Lock_context.Lock_context );