score: Add stack free handler to TCB

This avoids a dependency to the stack free function in the thread
destruction.

Update #3959.

cpukit/Makefile.am

@@ -933,6 +933,7 @@ librtemscpu_a_SOURCES += score/src/schedulercbsreleasejob.c
 librtemscpu_a_SOURCES += score/src/schedulercbsunblock.c
 librtemscpu_a_SOURCES += score/src/stackallocator.c
 librtemscpu_a_SOURCES += score/src/stackallocatorfree.c
+librtemscpu_a_SOURCES += score/src/stackallocatorfreenothing.c
 librtemscpu_a_SOURCES += score/src/stackallocatorinit.c
 librtemscpu_a_SOURCES += score/src/pheapallocate.c
 librtemscpu_a_SOURCES += score/src/pheapextend.c

cpukit/include/rtems/score/stackimpl.h

@@ -166,6 +166,13 @@ void *_Stack_Allocate( size_t stack_size );
  */
 void _Stack_Free( void *stack_area );
 
+/**
+ * @brief This function does nothing.
+ *
+ * @param stack_area is not used.
+ */
+void _Stack_Free_nothing( void *stack_area );
+
 /** @} */
 
 #ifdef __cplusplus

cpukit/include/rtems/score/thread.h

@@ -194,10 +194,9 @@ typedef struct {
   /** This field is the initial priority. */
   Priority_Control                     initial_priority;
   /**
-   * @brief This field is a pointer to the allocated stack area, otherwise it
+   * @brief This field points to the handler which should free the stack.
-   * is NULL.
    */
-  void                                *allocated_stack;
+  void                              ( *stack_free )( void * );
   /** This field is the stack information. */
   Stack_Control                        Initial_stack;
   #if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )

cpukit/include/rtems/score/threadimpl.h

@@ -144,9 +144,11 @@ typedef struct {
   size_t stack_size;
 
   /**
-   * @brief The address of the allocated stack area or NULL.
+   * @brief This member contains the handler to free the stack.
+   *
+   * It shall not be NULL.  Use _Stack_Free_nothing() if nothing is to free.
    */
-  void *allocated_stack;
+  void ( *stack_free )( void * );
 
   /**
    * @brief The new thread's priority.

cpukit/posix/src/pthreadcreate.c

@@ -218,8 +218,10 @@ int pthread_create(
   }
 
   if ( config.stack_area == NULL ) {
+    config.stack_free = _Stack_Free;
     config.stack_area = _Stack_Allocate( config.stack_size );
-    config.allocated_stack = config.stack_area;
+  } else {
+    config.stack_free = _Stack_Free_nothing;
   }
 
   status = ( config.stack_area != NULL );

cpukit/rtems/src/taskcreate.c

@@ -146,8 +146,8 @@ rtems_status_code rtems_task_create(
   }
 #endif
 
+  config.stack_free = _Stack_Free;
   config.stack_area = _Stack_Allocate( config.stack_size );
-  config.allocated_stack = config.stack_area;
   status = ( config.stack_area != NULL );
 
   /*

cpukit/score/src/stackallocatorfreenothing.c

@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup RTEMSScoreStack
+ *
+ * @brief _Stack_Free_nothing() Implementation
+ */
+
+/*
+ * Copyright (C) 2020 embedded brains GmbH (http://www.embedded-brains.de)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/score/stackimpl.h>
+
+void _Stack_Free_nothing( void *stack_area )
+{
+  (void) stack_area;
+}

cpukit/score/src/threadinitialize.c

@@ -36,8 +36,8 @@ bool _Thread_Initialize(
   uintptr_t                tls_size;
   bool                     extension_status;
   size_t                   i;
-  char                    *stack_area;
+  char                    *stack_begin;
-  size_t                   stack_size;
+  char                    *stack_end;
   Scheduler_Node          *scheduler_node;
 #if defined(RTEMS_SMP)
   Scheduler_Node          *scheduler_node_for_index;
@@ -61,7 +61,7 @@ bool _Thread_Initialize(
 
   /* Set everything to perform the error case clean up */
   scheduler_index = 0;
-  the_thread->Start.allocated_stack = config->allocated_stack;
+  the_thread->Start.stack_free = config->stack_free;
 
 #if defined(RTEMS_SMP)
   if (
@@ -83,16 +83,15 @@ bool _Thread_Initialize(
   }
 #endif
 
-  stack_area = config->stack_area;
+  stack_begin = config->stack_area;
-  stack_size = config->stack_size;
+  stack_end = stack_begin + config->stack_size;
 
   /* Allocate floating-point context in stack area */
 #if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
   if ( config->is_fp ) {
-    the_thread->fp_context = ( Context_Control_fp *) stack_area;
+    stack_end -= CONTEXT_FP_SIZE;
-    the_thread->Start.fp_context = ( Context_Control_fp *) stack_area;
+    the_thread->fp_context = (Context_Control_fp *) stack_end;
-    stack_size -= CONTEXT_FP_SIZE;
+    the_thread->Start.fp_context = (Context_Control_fp *) stack_end;
-    stack_area += CONTEXT_FP_SIZE;
   }
 #endif
 
@@ -102,17 +101,16 @@ bool _Thread_Initialize(
   if ( tls_size > 0 ) {
     uintptr_t tls_align;
 
+    stack_end -= tls_size;
     tls_align = (uintptr_t) _TLS_Alignment;
     the_thread->Start.tls_area = (void *)
-      ( ( (uintptr_t) stack_area + tls_align - 1 ) & ~( tls_align - 1 ) );
+      ( ( (uintptr_t) stack_end + tls_align - 1 ) & ~( tls_align - 1 ) );
-    stack_size -= tls_size;
-    stack_area += tls_size;
   }
 
   _Stack_Initialize(
-     &the_thread->Start.Initial_stack,
+    &the_thread->Start.Initial_stack,
-     stack_area,
+    stack_begin,
-     stack_size
+    stack_end - stack_begin
   );
 
   /*
@@ -279,6 +277,6 @@ failed:
     &information->Thread_queue_heads.Free,
     the_thread->Wait.spare_heads
   );
-  _Stack_Free( the_thread->Start.allocated_stack );
+  ( *the_thread->Start.stack_free )( the_thread->Start.Initial_stack.area );
   return false;
 }

cpukit/score/src/threadrestart.c

@@ -185,7 +185,7 @@ static void _Thread_Free( Thread_Control *the_thread )
    *  Free the rest of the memory associated with this task
    *  and set the associated pointers to NULL for safety.
    */
-  _Stack_Free( the_thread->Start.allocated_stack );
+  ( *the_thread->Start.stack_free )( the_thread->Start.Initial_stack.area );
 
 #if defined(RTEMS_SMP)
   _ISR_lock_Destroy( &the_thread->Scheduler.Lock );