[rtems commit] score: Fix heap protection

[Sebastian Huber]

Module:    rtems
Branch:    master
Commit:    5f104eefb12c3fceb4bfc2ae7715aca20f3a9561
Changeset: http://git.rtems.org/rtems/commit/?id=5f104eefb12c3fceb4bfc2ae7715aca20f3a9561

Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
Date:      Tue Mar 25 08:53:33 2014 +0100

score: Fix heap protection

Partially revert commit 2a713e3b944625c45154f0ea7f5703e918de758.

---

 cpukit/score/src/heapfree.c |   28 +++++++++++++++++++++-------
 1 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/cpukit/score/src/heapfree.c b/cpukit/score/src/heapfree.c
index e577e13..c45c294 100644
--- a/cpukit/score/src/heapfree.c
+++ b/cpukit/score/src/heapfree.c
@@ -20,6 +20,7 @@
 #endif
 
 #include <rtems/score/heapimpl.h>
+#include <rtems/score/threaddispatch.h>
 
 #ifndef HEAP_PROTECTION
   #define _Heap_Protection_determine_block_free( heap, block ) true
@@ -82,13 +83,26 @@
     bool do_free = true;
     Heap_Block *const next = block->Protection_begin.next_delayed_free_block;
 
-    if ( next == NULL ) {
-      _Heap_Protection_delay_block_free( heap, block );
-      do_free = false;
-    } else if ( next == HEAP_PROTECTION_OBOLUS ) {
-      _Heap_Protection_check_free_block( heap, block );
-    } else {
-      _Heap_Protection_block_error( heap, block );
+    /*
+     * Sometimes after a free the allocated area is still in use.  An example
+     * is the task stack of a thread that deletes itself.  The thread dispatch
+     * disable level is a way to detect this use case.
+     */
+    if ( _Thread_Dispatch_is_enabled() ) {
+      if ( next == NULL ) {
+        _Heap_Protection_delay_block_free( heap, block );
+        do_free = false;
+      } else if ( next == HEAP_PROTECTION_OBOLUS ) {
+        _Heap_Protection_check_free_block( heap, block );
+      } else {
+        _Heap_Protection_block_error( heap, block );
+      }
+    } else if ( next == NULL ) {
+      /*
+       * This is a hack to prevent heavy workspace fragmentation which would
+       * lead to test suite failures.
+       */
+      _Heap_Protection_free_all_delayed_blocks( heap );
     }
 
     return do_free;