summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorSebastian Huber <sebastian.huber@embedded-brains.de>2020-02-10 10:28:49 +0100
committerSebastian Huber <sebastian.huber@embedded-brains.de>2020-02-10 10:29:21 +0100
commite57733a9bd31398fb0fbe00e5ab9fb95e68e7830 (patch)
tree024be40493362e54fc7f5e5f44c353797f0cd34a
parentb6c61e38abe52f3655ec307323394abc6f05ff36 (diff)
downloadrtems-docs-e57733a9bd31398fb0fbe00e5ab9fb95e68e7830.tar.bz2
c-user: Document CONFIGURE_DIRTY_MEMORY
Close #3843.
-rw-r--r--c-user/configuring_a_system.rst36
1 files changed, 35 insertions, 1 deletions
diff --git a/c-user/configuring_a_system.rst b/c-user/configuring_a_system.rst
index 81bc9bb..00584c1 100644
--- a/c-user/configuring_a_system.rst
+++ b/c-user/configuring_a_system.rst
@@ -425,6 +425,38 @@ General System Configuration
This section defines the general system configuration options supported by
``<rtems/confdefs.h>``.
+.. index:: CONFIGURE_DIRTY_MEMORY
+
+.. _CONFIGURE_DIRTY_MEMORY:
+
+CONFIGURE_DIRTY_MEMORY
+----------------------
+
+CONSTANT:
+ ``CONFIGURE_DIRTY_MEMORY``
+
+DATA TYPE:
+ Boolean feature macro.
+
+RANGE:
+ Defined or undefined.
+
+DEFAULT VALUE:
+ By default, the memory used by the RTEMS Workspace and the C Program Heap
+ is uninitialized memory.
+
+DESCRIPTION:
+ This macro indicates whether RTEMS should dirty the memory used by the
+ RTEMS Workspace and the C Program Heap as part of its initialization. If
+ defined, the memory areas are dirtied with a ``0xCF`` byte pattern.
+ Otherwise, they are not.
+
+NOTES:
+ Dirtying memory can add significantly to system boot time. It may assist
+ in finding code that assumes memory starts set to zero. In case
+ :ref:`CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY` is also defined, then the
+ memory is first dirtied and then zeroed.
+
.. index:: CONFIGURE_EXTRA_TASK_STACKS
.. index:: memory for task tasks
@@ -1006,7 +1038,9 @@ DESCRIPTION:
NOTES:
Zeroing memory can add significantly to system boot time. It is not
- necessary for RTEMS but is often assumed by support libraries.
+ necessary for RTEMS but is often assumed by support libraries. In case
+ :ref:`CONFIGURE_DIRTY_MEMORY` is also defined, then the memory is first
+ dirtied and then zeroed.
Classic API Configuration
=========================