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diff --git a/c-user/config/bdbuf.rst b/c-user/config/bdbuf.rst new file mode 100644 index 0000000..2d27d54 --- /dev/null +++ b/c-user/config/bdbuf.rst @@ -0,0 +1,533 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. Copyright (C) 2020, 2021 embedded brains GmbH & Co. KG +.. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR) + +.. This file is part of the RTEMS quality process and was automatically +.. generated. If you find something that needs to be fixed or +.. worded better please post a report or patch to an RTEMS mailing list +.. or raise a bug report: +.. +.. https://www.rtems.org/bugs.html +.. +.. For information on updating and regenerating please refer to the How-To +.. section in the Software Requirements Engineering chapter of the +.. RTEMS Software Engineering manual. The manual is provided as a part of +.. a release. For development sources please refer to the online +.. documentation at: +.. +.. https://docs.rtems.org + +.. Generated from spec:/acfg/if/group-bdbuf + +Block Device Cache Configuration +================================ + +This section describes configuration options related to the Block Device Cache +(bdbuf). + +.. Generated from spec:/acfg/if/appl-needs-libblock + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_APPLICATION_NEEDS_LIBBLOCK + +.. _CONFIGURE_APPLICATION_NEEDS_LIBBLOCK: + +CONFIGURE_APPLICATION_NEEDS_LIBBLOCK +------------------------------------ + +.. rubric:: CONSTANT: + +``CONFIGURE_APPLICATION_NEEDS_LIBBLOCK`` + +.. 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 Block Device Cache is +initialized during system initialization. + +.. rubric:: NOTES: + +Each option of the Block Device Cache (bdbuf) configuration can be explicitly +set by the user with the configuration options below. The Block Device Cache +is used for example by the RFS and DOSFS filesystems. + +.. Generated from spec:/acfg/if/bdbuf-buffer-max-size + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_BDBUF_BUFFER_MAX_SIZE + +.. _CONFIGURE_BDBUF_BUFFER_MAX_SIZE: + +CONFIGURE_BDBUF_BUFFER_MAX_SIZE +------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_BDBUF_BUFFER_MAX_SIZE`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 4096. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the maximum size of a buffer +in bytes. + +.. 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 an integral multiple of + :ref:`CONFIGURE_BDBUF_BUFFER_MIN_SIZE`. + +.. Generated from spec:/acfg/if/bdbuf-buffer-min-size + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_BDBUF_BUFFER_MIN_SIZE + +.. _CONFIGURE_BDBUF_BUFFER_MIN_SIZE: + +CONFIGURE_BDBUF_BUFFER_MIN_SIZE +------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_BDBUF_BUFFER_MIN_SIZE`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 512. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the minimum size of a buffer +in bytes. + +.. 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/bdbuf-cache-memory-size + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_BDBUF_CACHE_MEMORY_SIZE + +.. _CONFIGURE_BDBUF_CACHE_MEMORY_SIZE: + +CONFIGURE_BDBUF_CACHE_MEMORY_SIZE +--------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_BDBUF_CACHE_MEMORY_SIZE`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 32768. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the size of the cache memory +in bytes. + +.. 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 + `SIZE_MAX <https://en.cppreference.com/w/c/types/limits>`_. + +.. Generated from spec:/acfg/if/bdbuf-max-read-ahead-blocks + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_BDBUF_MAX_READ_AHEAD_BLOCKS + +.. _CONFIGURE_BDBUF_MAX_READ_AHEAD_BLOCKS: + +CONFIGURE_BDBUF_MAX_READ_AHEAD_BLOCKS +------------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_BDBUF_MAX_READ_AHEAD_BLOCKS`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 0. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the maximum blocks per +read-ahead request. + +.. rubric:: NOTES: + +A value of 0 disables the read-ahead task (default). The read-ahead task +will issue speculative read transfers if a sequential access pattern is +detected. This can improve the performance on some systems. + +.. 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/bdbuf-max-write-blocks + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_BDBUF_MAX_WRITE_BLOCKS + +.. _CONFIGURE_BDBUF_MAX_WRITE_BLOCKS: + +CONFIGURE_BDBUF_MAX_WRITE_BLOCKS +-------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_BDBUF_MAX_WRITE_BLOCKS`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 16. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the maximum blocks per write +request. + +.. 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/bdbuf-read-ahead-task-priority + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_BDBUF_READ_AHEAD_TASK_PRIORITY + +.. _CONFIGURE_BDBUF_READ_AHEAD_TASK_PRIORITY: + +CONFIGURE_BDBUF_READ_AHEAD_TASK_PRIORITY +---------------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_BDBUF_READ_AHEAD_TASK_PRIORITY`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 15. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the read-ahead task priority. + +.. rubric:: CONSTRAINTS: + +The value of the configuration option shall be a valid Classic API task +priority. The set of valid task priorities depends on the scheduler +configuration. + +.. Generated from spec:/acfg/if/bdbuf-task-stack-size + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_BDBUF_TASK_STACK_SIZE + +.. _CONFIGURE_BDBUF_TASK_STACK_SIZE: + +CONFIGURE_BDBUF_TASK_STACK_SIZE +------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_BDBUF_TASK_STACK_SIZE`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is :c:macro:`RTEMS_MINIMUM_STACK_SIZE`. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the task stack size of the +Block Device Cache tasks in bytes. + +.. rubric:: CONSTRAINTS: + +The following constraints apply to this configuration option: + +* The value of the configuration option shall be greater than or equal to + :ref:`CONFIGURE_MINIMUM_TASK_STACK_SIZE`. + +* 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 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>`_. + +.. Generated from spec:/acfg/if/bdbuf-swapout-block-hold + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_SWAPOUT_BLOCK_HOLD + +.. _CONFIGURE_SWAPOUT_BLOCK_HOLD: + +CONFIGURE_SWAPOUT_BLOCK_HOLD +---------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_SWAPOUT_BLOCK_HOLD`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 1000. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the swapout task maximum block +hold time in milliseconds. + +.. 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/bdbuf-swapout-swap-period + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_SWAPOUT_SWAP_PERIOD + +.. _CONFIGURE_SWAPOUT_SWAP_PERIOD: + +CONFIGURE_SWAPOUT_SWAP_PERIOD +----------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_SWAPOUT_SWAP_PERIOD`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 250. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the swapout task swap period +in milliseconds. + +.. 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/bdbuf-swapout-task-priority + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_SWAPOUT_TASK_PRIORITY + +.. _CONFIGURE_SWAPOUT_TASK_PRIORITY: + +CONFIGURE_SWAPOUT_TASK_PRIORITY +------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_SWAPOUT_TASK_PRIORITY`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 15. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the swapout task priority. + +.. rubric:: CONSTRAINTS: + +The value of the configuration option shall be a valid Classic API task +priority. The set of valid task priorities depends on the scheduler +configuration. + +.. Generated from spec:/acfg/if/bdbuf-swapout-worker-tasks + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_SWAPOUT_WORKER_TASKS + +.. _CONFIGURE_SWAPOUT_WORKER_TASKS: + +CONFIGURE_SWAPOUT_WORKER_TASKS +------------------------------ + +.. rubric:: CONSTANT: + +``CONFIGURE_SWAPOUT_WORKER_TASKS`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 0. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the swapout worker task count. + +.. 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/bdbuf-swapout-worker-taskp-riority + +.. raw:: latex + + \clearpage + +.. index:: CONFIGURE_SWAPOUT_WORKER_TASK_PRIORITY + +.. _CONFIGURE_SWAPOUT_WORKER_TASK_PRIORITY: + +CONFIGURE_SWAPOUT_WORKER_TASK_PRIORITY +-------------------------------------- + +.. rubric:: CONSTANT: + +``CONFIGURE_SWAPOUT_WORKER_TASK_PRIORITY`` + +.. rubric:: OPTION TYPE: + +This configuration option is an integer define. + +.. rubric:: DEFAULT VALUE: + +The default value is 15. + +.. rubric:: DESCRIPTION: + +The value of this configuration option defines the swapout worker task +priority. + +.. rubric:: CONSTRAINTS: + +The value of the configuration option shall be a valid Classic API task +priority. The set of valid task priorities depends on the scheduler +configuration. |