mirror of
https://git.rtems.org/rtems-docs/
synced 2025-06-03 15:10:23 +08:00
1c8ce332e2
Clear the page for each configuration options similar to the directives. Use a rubric instead of a definition list for the application configuration options similar to the directive documentation pages. For direcives and application configuration options use the same rubric order. Generalize value constraints to constraints. This patch does not change hand written content.
1086 lines
29 KiB
ReStructuredText
1086 lines
29 KiB
ReStructuredText
.. SPDX-License-Identifier: CC-BY-SA-4.0
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.. Copyright (C) 2020, 2021 embedded brains GmbH (http://www.embedded-brains.de)
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.. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR)
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.. This file is part of the RTEMS quality process and was automatically
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.. generated. If you find something that needs to be fixed or
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.. worded better please post a report or patch to an RTEMS mailing list
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.. or raise a bug report:
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..
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.. https://www.rtems.org/bugs.html
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..
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.. For information on updating and regenerating please refer to the How-To
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.. section in the Software Requirements Engineering chapter of the
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.. RTEMS Software Engineering manual. The manual is provided as a part of
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.. a release. For development sources please refer to the online
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.. documentation at:
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..
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.. https://docs.rtems.org
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.. Generated from spec:/acfg/if/group-general
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General System Configuration
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============================
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This section describes general system configuration options.
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.. Generated from spec:/acfg/if/dirty-memory
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_DIRTY_MEMORY
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.. _CONFIGURE_DIRTY_MEMORY:
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CONFIGURE_DIRTY_MEMORY
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----------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_DIRTY_MEMORY``
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.. rubric:: OPTION TYPE:
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This configuration option is a boolean feature define.
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.. rubric:: DEFAULT CONFIGURATION:
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If this configuration option is undefined, then the described feature is not
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enabled.
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.. rubric:: DESCRIPTION:
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In case this configuration option is defined, then the memory areas used for
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the RTEMS Workspace and the C Program Heap are dirtied with a ``0xCF`` byte
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pattern during system initialization.
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.. rubric:: NOTES:
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Dirtying memory can add significantly to system initialization time. It may
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assist in finding code that incorrectly assumes the contents of free memory
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areas is cleared to zero during system initialization. In case
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:ref:`CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY` is also defined, then the
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memory is first dirtied and then zeroed.
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See also :ref:`CONFIGURE_MALLOC_DIRTY`.
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.. Generated from spec:/acfg/if/disable-newlib-reentrancy
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_DISABLE_NEWLIB_REENTRANCY
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.. _CONFIGURE_DISABLE_NEWLIB_REENTRANCY:
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CONFIGURE_DISABLE_NEWLIB_REENTRANCY
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-----------------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_DISABLE_NEWLIB_REENTRANCY``
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.. rubric:: OPTION TYPE:
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This configuration option is a boolean feature define.
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.. rubric:: DEFAULT CONFIGURATION:
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If this configuration option is undefined, then the described feature is not
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enabled.
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.. rubric:: DESCRIPTION:
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In case this configuration option is defined, then the Newlib reentrancy
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support per thread is disabled and a global reentrancy structure is used.
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.. rubric:: NOTES:
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You can enable this option to reduce the size of the :term:`TCB`. Use this
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option with care, since it can lead to race conditions and undefined system
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behaviour. For example, :c:macro:`errno` is no longer a thread-local
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variable if this option is enabled.
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.. Generated from spec:/acfg/if/executive-ram-size
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_EXECUTIVE_RAM_SIZE
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.. _CONFIGURE_EXECUTIVE_RAM_SIZE:
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CONFIGURE_EXECUTIVE_RAM_SIZE
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----------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_EXECUTIVE_RAM_SIZE``
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.. rubric:: OPTION TYPE:
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This configuration option is an integer define.
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.. rubric:: DEFAULT VALUE:
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If this configuration option is undefined, then the RTEMS Workspace and task
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stack space size is calculated by ``<rtems/confdefs.h>`` based on the values
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configuration options.
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.. rubric:: DESCRIPTION:
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The value of this configuration option defines the RTEMS Workspace size in
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bytes.
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.. rubric:: NOTES:
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This is an advanced configuration option. Use it only if you know exactly
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what you are doing.
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.. rubric:: CONSTRAINTS:
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The following constraints apply to this configuration option:
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* The value of the configuration option shall be greater than or equal to zero.
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* The value of the configuration option shall be less than or equal to
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`UINTPTR_MAX <https://en.cppreference.com/w/c/types/integer>`_.
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* The value of the configuration option shall be less than or equal to a
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BSP-specific and application-specific value which depends on the size of the
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memory available to the application.
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.. Generated from spec:/acfg/if/extra-task-stacks
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_EXTRA_TASK_STACKS
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.. index:: memory for task tasks
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.. _CONFIGURE_EXTRA_TASK_STACKS:
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CONFIGURE_EXTRA_TASK_STACKS
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---------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_EXTRA_TASK_STACKS``
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.. rubric:: OPTION TYPE:
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This configuration option is an integer define.
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.. rubric:: DEFAULT VALUE:
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The default value is 0.
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.. rubric:: DESCRIPTION:
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The value of this configuration option defines the number of bytes the
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applications wishes to add to the task stack requirements calculated by
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``<rtems/confdefs.h>``.
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.. rubric:: NOTES:
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This parameter is very important. If the application creates tasks with
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stacks larger then the minimum, then that memory is **not** accounted for by
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``<rtems/confdefs.h>``.
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.. rubric:: CONSTRAINTS:
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The following constraints apply to this configuration option:
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* The value of the configuration option shall be greater than or equal to zero.
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* The value of the configuration option shall be small enough so that the task
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stack space calculation carried out by ``<rtems/confdefs.h>`` does not
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overflow an integer of type `uintptr_t
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<https://en.cppreference.com/w/c/types/integer>`_.
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.. Generated from spec:/acfg/if/initial-extensions
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_INITIAL_EXTENSIONS
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.. _CONFIGURE_INITIAL_EXTENSIONS:
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CONFIGURE_INITIAL_EXTENSIONS
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----------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_INITIAL_EXTENSIONS``
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.. rubric:: OPTION TYPE:
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This configuration option is an initializer define.
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.. rubric:: DEFAULT VALUE:
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The default value is the empty list.
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.. rubric:: DESCRIPTION:
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The value of this configuration option is used to initialize the table of
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initial user extensions.
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.. rubric:: NOTES:
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The value of this configuration option is placed before the entries of
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:ref:`BSP_INITIAL_EXTENSION` and after the entries of all other initial
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user extensions.
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.. rubric:: CONSTRAINTS:
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The value of the configuration option shall be a list of initializers for
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structures of type :c:type:`rtems_extensions_table`.
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.. Generated from spec:/acfg/if/interrupt-stack-size
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_INTERRUPT_STACK_SIZE
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.. index:: interrupt stack size
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.. _CONFIGURE_INTERRUPT_STACK_SIZE:
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CONFIGURE_INTERRUPT_STACK_SIZE
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------------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_INTERRUPT_STACK_SIZE``
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.. rubric:: OPTION TYPE:
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This configuration option is an integer define.
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.. rubric:: DEFAULT VALUE:
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The default value is :ref:`BSP_INTERRUPT_STACK_SIZE` in case it is defined,
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otherwise the default value is :c:macro:`CPU_STACK_MINIMUM_SIZE`.
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.. rubric:: DESCRIPTION:
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The value of this configuration option defines the size of an interrupt stack
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in bytes.
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.. rubric:: NOTES:
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There is one interrupt stack available for each configured processor
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(:ref:`CONFIGURE_MAXIMUM_PROCESSORS`). The interrupt stack areas are
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statically allocated in a special linker section (``.rtemsstack.interrupt``).
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The placement of this linker section is BSP-specific.
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Some BSPs use the interrupt stack as the initialization stack which is used
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to perform the sequential system initialization before the multithreading
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is started.
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The interrupt stacks are covered by the stack checker, see
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:ref:`CONFIGURE_STACK_CHECKER_ENABLED`. However, using a too small interrupt stack
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size may still result in undefined behaviour.
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In releases before RTEMS 5.1 the default value was
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:ref:`CONFIGURE_MINIMUM_TASK_STACK_SIZE` instead of
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:c:macro:`CPU_STACK_MINIMUM_SIZE`.
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.. rubric:: CONSTRAINTS:
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The following constraints apply to this configuration option:
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* The value of the configuration option shall be greater than or equal to a
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BSP-specific and application-specific minimum value.
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* The value of the configuration option shall be small enough so that the
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interrupt stack area calculation carried out by ``<rtems/confdefs.h>`` does
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not overflow an integer of type `size_t
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<https://en.cppreference.com/w/c/types/size_t>`_.
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* The value of the configuration option shall be aligned according to
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:c:macro:`CPU_INTERRUPT_STACK_ALIGNMENT`.
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.. Generated from spec:/acfg/if/malloc-dirty
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_MALLOC_DIRTY
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.. _CONFIGURE_MALLOC_DIRTY:
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CONFIGURE_MALLOC_DIRTY
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----------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_MALLOC_DIRTY``
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.. rubric:: OPTION TYPE:
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This configuration option is a boolean feature define.
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.. rubric:: DEFAULT CONFIGURATION:
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If this configuration option is undefined, then the described feature is not
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enabled.
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.. rubric:: DESCRIPTION:
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In case this configuration option is defined, then each memory area returned
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by C Program Heap allocator functions such as :c:func:`malloc` is dirtied
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with a ``0xCF`` byte pattern before it is handed over to the application.
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.. rubric:: NOTES:
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The dirtying performed by this option is carried out for each successful
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memory allocation from the C Program Heap in contrast to
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:ref:`CONFIGURE_DIRTY_MEMORY` which dirties the memory only once during the
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system initialization.
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.. Generated from spec:/acfg/if/max-file-descriptors
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_MAXIMUM_FILE_DESCRIPTORS
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.. index:: maximum file descriptors
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.. _CONFIGURE_MAXIMUM_FILE_DESCRIPTORS:
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CONFIGURE_MAXIMUM_FILE_DESCRIPTORS
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----------------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_MAXIMUM_FILE_DESCRIPTORS``
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.. rubric:: OPTION TYPE:
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This configuration option is an integer define.
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.. rubric:: DEFAULT VALUE:
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The default value is 3.
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.. rubric:: DESCRIPTION:
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The value of this configuration option defines the maximum number of file
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like objects that can be concurrently open.
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.. rubric:: NOTES:
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The default value of three file descriptors allows RTEMS to support standard
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input, output, and error I/O streams on :file:`/dev/console`.
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.. rubric:: CONSTRAINTS:
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The following constraints apply to this configuration option:
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* The value of the configuration option shall be greater than or equal to zero.
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* The value of the configuration option shall be less than or equal to
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`SIZE_MAX <https://en.cppreference.com/w/c/types/limits>`_.
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* The value of the configuration option shall be less than or equal to a
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BSP-specific and application-specific value which depends on the size of the
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memory available to the application.
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.. Generated from spec:/acfg/if/max-processors
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_MAXIMUM_PROCESSORS
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.. _CONFIGURE_MAXIMUM_PROCESSORS:
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CONFIGURE_MAXIMUM_PROCESSORS
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----------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_MAXIMUM_PROCESSORS``
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.. rubric:: OPTION TYPE:
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This configuration option is an integer define.
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.. rubric:: DEFAULT VALUE:
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The default value is 1.
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.. rubric:: DESCRIPTION:
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The value of this configuration option defines the maximum number of
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processors an application intends to use. The number of actually available
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processors depends on the hardware and may be less. It is recommended to use
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the smallest value suitable for the application in order to save memory.
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Each processor needs an IDLE task stack and interrupt stack for example.
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.. rubric:: NOTES:
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If there are more processors available than configured, the rest will be
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ignored.
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This configuration option is only evaluated in SMP configurations (e.g. RTEMS
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was built with the ``--enable-smp`` build configuration option). In all
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other configurations it has no effect.
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.. rubric:: CONSTRAINTS:
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The following constraints apply to this configuration option:
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* The value of the configuration option shall be greater than or equal to one.
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* The value of the configuration option shall be less than or equal to
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:c:macro:`CPU_MAXIMUM_PROCESSORS`.
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.. Generated from spec:/acfg/if/max-thread-name-size
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.. raw:: latex
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\clearpage
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.. index:: CONFIGURE_MAXIMUM_THREAD_NAME_SIZE
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.. index:: maximum thread name size
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.. _CONFIGURE_MAXIMUM_THREAD_NAME_SIZE:
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CONFIGURE_MAXIMUM_THREAD_NAME_SIZE
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----------------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_MAXIMUM_THREAD_NAME_SIZE``
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.. rubric:: OPTION TYPE:
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This configuration option is an integer define.
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.. rubric:: DEFAULT VALUE:
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The default value is 16.
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.. rubric:: DESCRIPTION:
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The value of this configuration option defines the maximum thread name size
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including the terminating ``NUL`` character.
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.. rubric:: NOTES:
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The default value was chosen for Linux compatibility, see
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`pthread_setname_np() <http://man7.org/linux/man-pages/man3/pthread_setname_np.3.html>`_.
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The size of the thread control block is increased by the maximum thread name
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size.
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This configuration option is available since RTEMS 5.1.
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.. rubric:: CONSTRAINTS:
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The following constraints apply to this configuration option:
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* The value of the configuration option shall be greater than or equal to zero.
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* The value of the configuration option shall be less than or equal to
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`SIZE_MAX <https://en.cppreference.com/w/c/types/limits>`_.
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* The value of the configuration option shall be less than or equal to a
|
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BSP-specific and application-specific value which depends on the size of the
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memory available to the application.
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.. Generated from spec:/acfg/if/memory-overhead
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.. raw:: latex
|
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\clearpage
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.. index:: CONFIGURE_MEMORY_OVERHEAD
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.. _CONFIGURE_MEMORY_OVERHEAD:
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CONFIGURE_MEMORY_OVERHEAD
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-------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_MEMORY_OVERHEAD``
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|
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.. rubric:: OPTION TYPE:
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This configuration option is an integer define.
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.. rubric:: DEFAULT VALUE:
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The default value is 0.
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.. rubric:: DESCRIPTION:
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|
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The value of this configuration option defines the number of kilobytes the
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application wishes to add to the RTEMS Workspace size calculated by
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``<rtems/confdefs.h>``.
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.. rubric:: NOTES:
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This configuration option should only be used when it is suspected that a bug
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in ``<rtems/confdefs.h>`` has resulted in an underestimation. Typically the
|
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memory allocation will be too low when an application does not account for
|
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all message queue buffers or task stacks, see
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:ref:`CONFIGURE_MESSAGE_BUFFER_MEMORY`.
|
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.. rubric:: CONSTRAINTS:
|
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The following constraints apply to this configuration option:
|
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* The value of the configuration option shall be greater than or equal to zero.
|
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|
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* The value of the configuration option shall be less than or equal to a
|
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BSP-specific and application-specific value which depends on the size of the
|
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memory available to the application.
|
|
|
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* The value of the configuration option shall be small enough so that the RTEMS
|
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Workspace size calculation carried out by ``<rtems/confdefs.h>`` does not
|
|
overflow an integer of type `uintptr_t
|
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<https://en.cppreference.com/w/c/types/integer>`_.
|
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|
|
.. Generated from spec:/acfg/if/message-buffer-memory
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.. raw:: latex
|
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|
|
\clearpage
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|
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.. index:: CONFIGURE_MESSAGE_BUFFER_MEMORY
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.. index:: configure message queue buffer memory
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.. index:: CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE
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.. index:: memory for a single message queue's buffers
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.. _CONFIGURE_MESSAGE_BUFFER_MEMORY:
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CONFIGURE_MESSAGE_BUFFER_MEMORY
|
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-------------------------------
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.. rubric:: CONSTANT:
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``CONFIGURE_MESSAGE_BUFFER_MEMORY``
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|
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.. rubric:: OPTION TYPE:
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|
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This configuration option is an integer define.
|
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|
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.. rubric:: DEFAULT VALUE:
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|
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The default value is 0.
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|
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.. rubric:: DESCRIPTION:
|
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|
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The value of this configuration option defines the number of bytes reserved
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for message queue buffers in the RTEMS Workspace.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
The configuration options :ref:`CONFIGURE_MAXIMUM_MESSAGE_QUEUES` and
|
|
:ref:`CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES` define only how many message
|
|
queues can be created by the application. The memory for the message
|
|
buffers is configured by this option. For each message queue you have to
|
|
reserve some memory for the message buffers. The size depends on the
|
|
maximum number of pending messages and the maximum size of the messages of
|
|
a message queue. Use the ``CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE()`` macro
|
|
to specify the message buffer memory for each message queue and sum them up
|
|
to define the value for ``CONFIGURE_MAXIMUM_MESSAGE_QUEUES``.
|
|
|
|
The interface for the ``CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE()`` help
|
|
macro is as follows:
|
|
|
|
.. code-block:: c
|
|
|
|
CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE( max_messages, max_msg_size )
|
|
|
|
Where ``max_messages`` is the maximum number of pending messages and
|
|
``max_msg_size`` is the maximum size in bytes of the messages of the
|
|
corresponding message queue. Both parameters shall be compile time
|
|
constants. Not using this help macro (e.g. just using
|
|
``max_messages * max_msg_size``) may result in an underestimate of the
|
|
RTEMS Workspace size.
|
|
|
|
The following example illustrates how the
|
|
``CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE()`` help macro can be used to assist in
|
|
calculating the message buffer memory required. In this example, there are
|
|
two message queues used in this application. The first message queue has a
|
|
maximum of 24 pending messages with the message structure defined by the
|
|
type ``one_message_type``. The other message queue has a maximum of 500
|
|
pending messages with the message structure defined by the type
|
|
``other_message_type``.
|
|
|
|
.. code-block:: c
|
|
|
|
#define CONFIGURE_MESSAGE_BUFFER_MEMORY ( \
|
|
CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE( \
|
|
24, \
|
|
sizeof( one_message_type ) \
|
|
) \
|
|
+ CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE( \
|
|
500, \
|
|
sizeof( other_message_type ) \
|
|
) \
|
|
)
|
|
|
|
.. rubric:: CONSTRAINTS:
|
|
|
|
The following constraints apply to this configuration option:
|
|
|
|
* The value of the configuration option shall be greater than or equal to zero.
|
|
|
|
* The value of the configuration option shall be less than or equal to a
|
|
BSP-specific and application-specific value which depends on the size of the
|
|
memory available to the application.
|
|
|
|
* The value of the configuration option shall be small enough so that the RTEMS
|
|
Workspace size calculation carried out by ``<rtems/confdefs.h>`` does not
|
|
overflow an integer of type `uintptr_t
|
|
<https://en.cppreference.com/w/c/types/integer>`_.
|
|
|
|
.. Generated from spec:/acfg/if/microseconds-per-tick
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_MICROSECONDS_PER_TICK
|
|
.. index:: clock tick quantum
|
|
.. index:: tick quantum
|
|
|
|
.. _CONFIGURE_MICROSECONDS_PER_TICK:
|
|
|
|
CONFIGURE_MICROSECONDS_PER_TICK
|
|
-------------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_MICROSECONDS_PER_TICK``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is an integer define.
|
|
|
|
.. rubric:: DEFAULT VALUE:
|
|
|
|
The default value is 10000.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
The value of this configuration option defines the length of time in
|
|
microseconds between clock ticks (clock tick quantum).
|
|
|
|
When the clock tick quantum value is too low, the system will spend so much
|
|
time processing clock ticks that it does not have processing time available
|
|
to perform application work. In this case, the system will become
|
|
unresponsive.
|
|
|
|
The lowest practical time quantum varies widely based upon the speed of the
|
|
target hardware and the architectural overhead associated with
|
|
interrupts. In general terms, you do not want to configure it lower than is
|
|
needed for the application.
|
|
|
|
The clock tick quantum should be selected such that it all blocking and
|
|
delay times in the application are evenly divisible by it. Otherwise,
|
|
rounding errors will be introduced which may negatively impact the
|
|
application.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
This configuration option has no impact if the Clock Driver is not
|
|
configured, see :ref:`CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER`.
|
|
|
|
There may be Clock Driver specific limits on the resolution or maximum value
|
|
of a clock tick quantum.
|
|
|
|
.. rubric:: CONSTRAINTS:
|
|
|
|
The following constraints apply to this configuration option:
|
|
|
|
* The value of the configuration option shall be greater than or equal to a
|
|
value defined by the :term:`Clock Driver`.
|
|
|
|
* The value of the configuration option shall be less than or equal to a value
|
|
defined by the :term:`Clock Driver`.
|
|
|
|
* The resulting clock ticks per second should be an integer.
|
|
|
|
.. Generated from spec:/acfg/if/min-task-stack-size
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_MINIMUM_TASK_STACK_SIZE
|
|
.. index:: minimum task stack size
|
|
|
|
.. _CONFIGURE_MINIMUM_TASK_STACK_SIZE:
|
|
|
|
CONFIGURE_MINIMUM_TASK_STACK_SIZE
|
|
---------------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_MINIMUM_TASK_STACK_SIZE``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is an integer define.
|
|
|
|
.. rubric:: DEFAULT VALUE:
|
|
|
|
The default value is :c:macro:`CPU_STACK_MINIMUM_SIZE`.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
The value of this configuration option defines the minimum stack size in
|
|
bytes for every user task or thread in the system.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
Adjusting this parameter should be done with caution. Examining the actual
|
|
stack usage using the stack checker usage reporting facility is recommended
|
|
(see also :ref:`CONFIGURE_STACK_CHECKER_ENABLED`).
|
|
|
|
This parameter can be used to lower the minimum from that recommended. This
|
|
can be used in low memory systems to reduce memory consumption for
|
|
stacks. However, this shall be done with caution as it could increase the
|
|
possibility of a blown task stack.
|
|
|
|
This parameter can be used to increase the minimum from that
|
|
recommended. This can be used in higher memory systems to reduce the risk
|
|
of stack overflow without performing analysis on actual consumption.
|
|
|
|
By default, this configuration parameter defines also the minimum stack
|
|
size of POSIX threads. This can be changed with the
|
|
:ref:`CONFIGURE_MINIMUM_POSIX_THREAD_STACK_SIZE`
|
|
configuration option.
|
|
|
|
In releases before RTEMS 5.1 the ``CONFIGURE_MINIMUM_TASK_STACK_SIZE`` was
|
|
used to define the default value of :ref:`CONFIGURE_INTERRUPT_STACK_SIZE`.
|
|
|
|
.. rubric:: CONSTRAINTS:
|
|
|
|
The following constraints apply to this configuration option:
|
|
|
|
* The value of the configuration option shall be small enough so that the task
|
|
stack space calculation carried out by ``<rtems/confdefs.h>`` does not
|
|
overflow an integer of type `uintptr_t
|
|
<https://en.cppreference.com/w/c/types/integer>`_.
|
|
|
|
* The value of the configuration option shall be greater than or equal to a
|
|
BSP-specific and application-specific minimum value.
|
|
|
|
.. Generated from spec:/acfg/if/stack-checker-enabled
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_STACK_CHECKER_ENABLED
|
|
|
|
.. _CONFIGURE_STACK_CHECKER_ENABLED:
|
|
|
|
CONFIGURE_STACK_CHECKER_ENABLED
|
|
-------------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_STACK_CHECKER_ENABLED``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is a boolean feature define.
|
|
|
|
.. rubric:: DEFAULT CONFIGURATION:
|
|
|
|
If this configuration option is undefined, then the described feature is not
|
|
enabled.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
In case this configuration option is defined, then the stack checker is
|
|
enabled.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
The stack checker performs run-time stack bounds checking. This increases
|
|
the time required to create tasks as well as adding overhead to each context
|
|
switch.
|
|
|
|
In 4.9 and older, this configuration option was named ``STACK_CHECKER_ON``.
|
|
|
|
.. Generated from spec:/acfg/if/ticks-per-time-slice
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_TICKS_PER_TIMESLICE
|
|
.. index:: ticks per timeslice
|
|
|
|
.. _CONFIGURE_TICKS_PER_TIMESLICE:
|
|
|
|
CONFIGURE_TICKS_PER_TIMESLICE
|
|
-----------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_TICKS_PER_TIMESLICE``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is an integer define.
|
|
|
|
.. rubric:: DEFAULT VALUE:
|
|
|
|
The default value is 50.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
The value of this configuration option defines the length of the timeslice
|
|
quantum in ticks for each task.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
This configuration option has no impact if the Clock Driver is not
|
|
configured, see :ref:`CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER`.
|
|
|
|
.. rubric:: CONSTRAINTS:
|
|
|
|
The following constraints apply to this configuration option:
|
|
|
|
* The value of the configuration option shall be greater than or equal to zero.
|
|
|
|
* The value of the configuration option shall be less than or equal to
|
|
`UINT32_MAX <https://en.cppreference.com/w/c/types/integer>`_.
|
|
|
|
.. Generated from spec:/acfg/if/unified-work-areas
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_UNIFIED_WORK_AREAS
|
|
.. index:: unified work areas
|
|
.. index:: separate work areas
|
|
.. index:: RTEMS Workspace
|
|
.. index:: C Program Heap
|
|
|
|
.. _CONFIGURE_UNIFIED_WORK_AREAS:
|
|
|
|
CONFIGURE_UNIFIED_WORK_AREAS
|
|
----------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_UNIFIED_WORK_AREAS``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is a boolean feature define.
|
|
|
|
.. rubric:: DEFAULT CONFIGURATION:
|
|
|
|
If this configuration option is undefined, then there will be separate memory
|
|
pools for the RTEMS Workspace and C Program Heap.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
In case this configuration option is defined, then the RTEMS Workspace and
|
|
the C Program Heap will be one pool of memory.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
Having separate pools does have some advantages in the event a task blows a
|
|
stack or writes outside its memory area. However, in low memory systems the
|
|
overhead of the two pools plus the potential for unused memory in either
|
|
pool is very undesirable.
|
|
|
|
In high memory environments, this is desirable when you want to use the
|
|
:ref:`ConfigUnlimitedObjects` option. You will be able to create objects
|
|
until you run out of all available memory rather then just until you run out
|
|
of RTEMS Workspace.
|
|
|
|
.. Generated from spec:/acfg/if/unlimited-allocation-size
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_UNLIMITED_ALLOCATION_SIZE
|
|
|
|
.. _CONFIGURE_UNLIMITED_ALLOCATION_SIZE:
|
|
|
|
CONFIGURE_UNLIMITED_ALLOCATION_SIZE
|
|
-----------------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_UNLIMITED_ALLOCATION_SIZE``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is an integer define.
|
|
|
|
.. rubric:: DEFAULT VALUE:
|
|
|
|
The default value is 8.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
If :ref:`CONFIGURE_UNLIMITED_OBJECTS` is defined, then the value of this
|
|
configuration option defines the default objects maximum of all object
|
|
classes supporting :ref:`ConfigUnlimitedObjects` to
|
|
``rtems_resource_unlimited( CONFIGURE_UNLIMITED_ALLOCATION_SIZE )``.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
By allowing users to declare all resources as being unlimited the user can
|
|
avoid identifying and limiting the resources used.
|
|
|
|
The object maximum of each class can be configured also individually using
|
|
the :c:func:`rtems_resource_unlimited` macro.
|
|
|
|
.. rubric:: CONSTRAINTS:
|
|
|
|
The value of the configuration option shall meet the constraints of all object
|
|
classes to which it is applied.
|
|
|
|
.. Generated from spec:/acfg/if/unlimited-objects
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_UNLIMITED_OBJECTS
|
|
|
|
.. _CONFIGURE_UNLIMITED_OBJECTS:
|
|
|
|
CONFIGURE_UNLIMITED_OBJECTS
|
|
---------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_UNLIMITED_OBJECTS``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is a boolean feature define.
|
|
|
|
.. rubric:: DEFAULT CONFIGURATION:
|
|
|
|
If this configuration option is undefined, then the described feature is not
|
|
enabled.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
In case this configuration option is defined, then unlimited objects are used
|
|
by default.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
When using unlimited objects, it is common practice to also specify
|
|
:ref:`CONFIGURE_UNIFIED_WORK_AREAS` so the system operates with a single pool
|
|
of memory for both RTEMS Workspace and C Program Heap.
|
|
|
|
This option does not override an explicit configuration for a particular
|
|
object class by the user.
|
|
|
|
See also :ref:`CONFIGURE_UNLIMITED_ALLOCATION_SIZE`.
|
|
|
|
.. Generated from spec:/acfg/if/verbose-system-init
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_VERBOSE_SYSTEM_INITIALIZATION
|
|
|
|
.. _CONFIGURE_VERBOSE_SYSTEM_INITIALIZATION:
|
|
|
|
CONFIGURE_VERBOSE_SYSTEM_INITIALIZATION
|
|
---------------------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_VERBOSE_SYSTEM_INITIALIZATION``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is a boolean feature define.
|
|
|
|
.. rubric:: DEFAULT CONFIGURATION:
|
|
|
|
If this configuration option is undefined, then the described feature is not
|
|
enabled.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
In case this configuration option is defined, then the system initialization
|
|
is verbose.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
You may use this feature to debug system initialization issues. The
|
|
:c:func:`printk` function is used to print the information.
|
|
|
|
.. Generated from spec:/acfg/if/zero-workspace-automatically
|
|
|
|
.. raw:: latex
|
|
|
|
\clearpage
|
|
|
|
.. index:: CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY
|
|
.. index:: clear C Program Heap
|
|
.. index:: clear RTEMS Workspace
|
|
.. index:: zero C Program Heap
|
|
.. index:: zero RTEMS Workspace
|
|
|
|
.. _CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY:
|
|
|
|
CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY
|
|
--------------------------------------
|
|
|
|
.. rubric:: CONSTANT:
|
|
|
|
``CONFIGURE_ZERO_WORKSPACE_AUTOMATICALLY``
|
|
|
|
.. rubric:: OPTION TYPE:
|
|
|
|
This configuration option is a boolean feature define.
|
|
|
|
.. rubric:: DEFAULT CONFIGURATION:
|
|
|
|
If this configuration option is undefined, then the described feature is not
|
|
enabled.
|
|
|
|
.. rubric:: DESCRIPTION:
|
|
|
|
In case this configuration option is defined, then the memory areas used for
|
|
the RTEMS Workspace and the C Program Heap are zeroed with a ``0x00`` byte
|
|
pattern during system initialization.
|
|
|
|
.. rubric:: NOTES:
|
|
|
|
Zeroing memory can add significantly to the system initialization time. It is
|
|
not 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.
|