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docs: Provide Chinese translation for api-reference/system/freertos.rst

Closes DOC-6132

See merge request espressif/esp-idf!25683
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48 changes: 26 additions & 22 deletions docs/en/api-reference/system/freertos.rst
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@@ -1,10 +1,14 @@
FreeRTOS (Overview)
===================
FreeRTOS Overview
=================

:link_to_translation:`zh_CN:[中文]`

Overview
--------

FreeRTOS is an open source real-time operating system kernel that acts as the operating system for ESP-IDF applications and is integrated into ESP-IDF as a component. The FreeRTOS component in ESP-IDF contains ports of the FreeRTOS kernel for all the CPU architectures used by ESP targets (i.e., Xtensa and RISC-V). Furthermore, ESP-IDF provides different implementations of FreeRTOS in order to support SMP (Symmetric Multiprocessing) on multi-core ESP targets. This document provides an overview of the FreeRTOS component, the FreeRTOS implementations offered by ESP-IDF, and the common aspects across all implementations.
FreeRTOS is an open source RTOS (real-time operating system) kernel that is integrated into ESP-IDF as a component. Thus, all ESP-IDF applications and many ESP-IDF components are written based on FreeRTOS. The FreeRTOS kernel is ported to all architectures (i.e., Xtensa and RISC-V) available of ESP chips.

Furthermore, ESP-IDF provides different implementations of FreeRTOS in order to support SMP (Symmetric Multiprocessing) on multi-core ESP chips. This document provides an overview of the FreeRTOS component, the different FreeRTOS implementations offered by ESP-IDF, and the common aspects across all implementations.

Implementations
---------------
Expand All @@ -14,11 +18,11 @@ The `official FreeRTOS <https://www.freertos.org/index.html>`_ (henceforth refer
ESP-IDF FreeRTOS
^^^^^^^^^^^^^^^^

ESP-IDF FreeRTOS is a FreeRTOS implementation based on Vanilla FreeRTOS v10.4.3, but contains significant modifications to support SMP. ESP-IDF FreeRTOS only supports two cores at most (i.e., dual core SMP), but is more optimized for this scenario by design. For more details regarding ESP-IDF FreeRTOS and its modifications, please refer to the :doc:`freertos_idf` document.
ESP-IDF FreeRTOS is a FreeRTOS implementation based on Vanilla FreeRTOS v10.4.3, but contains significant modifications to support SMP. ESP-IDF FreeRTOS only supports two cores at most (i.e., dual core SMP), but is more optimized for this scenario by design. For more details regarding ESP-IDF FreeRTOS and its modifications, please refer to the :doc:`freertos_idf` document.

.. note::
.. note::

ESP-IDF FreeRTOS is currently the default FreeRTOS implementation for ESP-IDF.
ESP-IDF FreeRTOS is currently the default FreeRTOS implementation for ESP-IDF.

.. only:: not esp32p4

Expand All @@ -27,21 +31,21 @@ ESP-IDF FreeRTOS
Amazon SMP FreeRTOS
^^^^^^^^^^^^^^^^^^^

Amazon SMP FreeRTOS is an SMP implementation of FreeRTOS that is officially supported by Amazon. Amazon SMP FreeRTOS is able to support N-cores (i.e., more than two cores). Amazon SMP FreeRTOS can be enabled via the :ref:`CONFIG_FREERTOS_SMP` option. For more details regarding Amazon SMP FreeRTOS, please refer to the `official Amazon SMP FreeRTOS documentation <https://freertos.org/symmetric-multiprocessing-introduction.html>`_.
Amazon SMP FreeRTOS is an SMP implementation of FreeRTOS that is officially supported by Amazon. Amazon SMP FreeRTOS is able to support N-cores (i.e., more than two cores). Amazon SMP FreeRTOS can be enabled via the :ref:`CONFIG_FREERTOS_SMP` option. For more details regarding Amazon SMP FreeRTOS, please refer to the `official Amazon SMP FreeRTOS documentation <https://freertos.org/symmetric-multiprocessing-introduction.html>`_.

.. warning::
.. warning::

The Amazon SMP FreeRTOS implementation (and its port in ESP-IDF) are currently in experimental/beta state. Therefore, significant behavioral changes and breaking API changes can occur.
The Amazon SMP FreeRTOS implementation (and its port in ESP-IDF) are currently in experimental/beta state. Therefore, significant behavioral changes and breaking API changes can occur.

Configuration
-------------

Kernel Configuration
^^^^^^^^^^^^^^^^^^^^

Vanilla FreeRTOS requires that ports and applications configure the kernel by adding various ``#define config...`` macros to ``FreeRTOSConfig.h``. Vanilla FreeRTOS supports a list of kernel configuration options which allow various kernel behaviors and features to be enabled or disabled.
Vanilla FreeRTOS requires that ports and applications configure the kernel by adding various ``#define config...`` macro definitions to the ``FreeRTOSConfig.h`` header file. Vanilla FreeRTOS supports a list of kernel configuration options which allow various kernel behaviors and features to be enabled or disabled.

**However, for all FreeRTOS ports in ESP-IDF, the ``FreeRTOSConfig.h`` file is considered private and must not be modified by users**. A large number of kernel configuration options in ``FreeRTOSConfig.h`` are hard coded as they are either required or not supported in ESP-IDF. All kernel configuration options that are configurable by the user are exposed via menuconfig under ``Component Config/FreeRTOS/Kernel``.
**However, for all FreeRTOS ports in ESP-IDF, the FreeRTOSConfig.h header file is considered private and must not be modified by users**. A large number of kernel configuration options in ``FreeRTOSConfig.h`` are hard-coded as they are either required/not supported by ESP-IDF. All kernel configuration options that are configurable by the user are exposed via menuconfig under ``Component Config/FreeRTOS/Kernel``.

For the full list of user configurable kernel options, see :doc:`/api-reference/kconfig`. The list below highlights some commonly used kernel configuration options:

Expand All @@ -68,7 +72,7 @@ Using FreeRTOS
Application Entry Point
^^^^^^^^^^^^^^^^^^^^^^^

Unlike Vanilla FreeRTOS, users of FreeRTOS in ESP-IDF **must never call** :cpp:func:`vTaskStartScheduler` and :cpp:func:`vTaskEndScheduler`. Instead, ESP-IDF starts FreeRTOS automatically. Users must define a ``void app_main(void)`` function which acts as the entry point for user's application and is automatically called on ESP-IDF startup.
Unlike Vanilla FreeRTOS, users of FreeRTOS in ESP-IDF **must never call** :cpp:func:`vTaskStartScheduler` and :cpp:func:`vTaskEndScheduler`. Instead, ESP-IDF starts FreeRTOS automatically. Users must define a ``void app_main(void)`` function which acts as the entry point for user's application and is automatically invoked on ESP-IDF startup.

- Typically, users would spawn the rest of their application's task from ``app_main``.
- The ``app_main`` function is allowed to return at any point (i.e., before the application terminates).
Expand All @@ -91,29 +95,29 @@ During startup, ESP-IDF and the FreeRTOS kernel automatically create multiple ta
- Affinity
- Priority
* - Idle Tasks (``IDLEx``)
- An idle task (``IDLEx``) is created for (and pinned to) each CPU, where ``x`` is the CPU's number.
- An idle task (``IDLEx``) is created for (and pinned to) each CPU core, where ``x`` is the CPU core's number
- :ref:`CONFIG_FREERTOS_IDLE_TASK_STACKSIZE`
- CPUx
- Core x
- ``0``
* - FreeRTOS Timer Task (``Tmr Svc``)
- FreeRTOS will create the Timer Service/Daemon Task if any FreeRTOS Timer APIs are called by the application.
- FreeRTOS will create the Timer Service/Daemon Task if any FreeRTOS Timer APIs are called by the application
- :ref:`CONFIG_FREERTOS_TIMER_TASK_STACK_DEPTH`
- CPU0
- Core 0
- :ref:`CONFIG_FREERTOS_TIMER_TASK_PRIORITY`
* - Main Task (``main``)
- Task that simply calls ``app_main``. This task will self delete when ``app_main`` returns
- :ref:`CONFIG_ESP_MAIN_TASK_STACK_SIZE`
- :ref:`CONFIG_ESP_MAIN_TASK_AFFINITY`
- ``1``
* - IPC Tasks (``ipcx``)
- When :ref:`CONFIG_FREERTOS_UNICORE` is false, an IPC task (``ipcx``) is created for (and pinned to) each CPU. IPC tasks are used to implement the Inter-processor Call (IPC) feature.
- When :ref:`CONFIG_FREERTOS_UNICORE` is false, an IPC task (``ipcx``) is created for (and pinned to) each CPU core. IPC tasks are used to implement the Inter-processor Call (IPC) feature.
- :ref:`CONFIG_ESP_IPC_TASK_STACK_SIZE`
- CPUx
- Core x
- ``24``
* - ESP Timer Task (``esp_timer``)
- ESP-IDF creates the ESP Timer Task used to process ESP Timer callbacks.
- ESP-IDF creates the ESP Timer Task used to process ESP Timer callbacks
- :ref:`CONFIG_ESP_TIMER_TASK_STACK_SIZE`
- CPU0
- Core 0
- ``22``

.. note::
Expand All @@ -129,10 +133,10 @@ ESP-IDF provides some supplemental features to FreeRTOS such as Ring Buffers, ES
FreeRTOS Heap
-------------

Vanilla FreeRTOS provides its own `selection of heap implementations <https://www.freertos.org/a00111.html>`_. However, ESP-IDF already implements its own heap (see :doc:`/api-reference/system/mem_alloc`), thus ESP-IDF does not make use of the heap implementations provided by Vanilla FreeRTOS. All FreeRTOS ports in ESP-IDF map FreeRTOS memory allocation/free calls (e.g., ``pvPortMalloc()`` and ``pvPortFree()``) to ESP-IDF heap API (i.e., :cpp:func:`heap_caps_malloc` and :cpp:func:`heap_caps_free`). However, the FreeRTOS ports ensure that all dynamic memory allocated by FreeRTOS is placed in internal memory.
Vanilla FreeRTOS provides its own `selection of heap implementations <https://www.freertos.org/a00111.html>`_. However, ESP-IDF already implements its own heap (see :doc:`/api-reference/system/mem_alloc`), thus ESP-IDF does not make use of the heap implementations provided by Vanilla FreeRTOS. All FreeRTOS ports in ESP-IDF map FreeRTOS memory allocation or free calls (e.g., ``pvPortMalloc()`` and ``pvPortFree()``) to ESP-IDF heap API (i.e., :cpp:func:`heap_caps_malloc` and :cpp:func:`heap_caps_free`). However, the FreeRTOS ports ensure that all dynamic memory allocated by FreeRTOS is placed in internal memory.

.. note::
If users wish to place FreeRTOS tasks/objects in external memory, users can use the following methods:

- Allocate the task/object using one of the ``...CreateWithCaps()`` API such as :cpp:func:`xTaskCreateWithCaps` and :cpp:func:`xQueueCreateWithCaps` (see :ref:`freertos-idf-additional-api` for more details).
- Allocate the task or object using one of the ``...CreateWithCaps()`` API, such as :cpp:func:`xTaskCreateWithCaps` and :cpp:func:`xQueueCreateWithCaps` (see :ref:`freertos-idf-additional-api` for more details).
- Manually allocate external memory for those objects using :cpp:func:`heap_caps_malloc`, then create the objects from the allocated memory using on of the ``...CreateStatic()`` FreeRTOS functions.
143 changes: 142 additions & 1 deletion docs/zh_CN/api-reference/system/freertos.rst
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@@ -1 +1,142 @@
.. include:: ../../../en/api-reference/system/freertos.rst
FreeRTOS 概述
===================

:link_to_translation:`en:[English]`

概述
--------

FreeRTOS 是一个开源的 RTOS(实时操作系统)内核,它以组件的形式集成到 ESP-IDF 中。因此,所有的 ESP-IDF 应用程序及多种 ESP-IDF 组件都基于 FreeRTOS 编写。FreeRTOS 内核已移植到 ESP 芯片的所有 CPU 架构(即 Xtensa 和 RISC-V)中。

此外,ESP-IDF 还提供了不同的 FreeRTOS 实现,支持在多核 ESP 目标芯片上的 SMP(对称多处理)。本文档主要介绍了 FreeRTOS 组件、ESP-IDF 提供的 FreeRTOS 实现,并简要介绍了这些实现的共同之处。

实现
---------------

`官方 FreeRTOS <https://www.freertos.org/zh-cn-cmn-s/index.html>`__ (下文称为原生 FreeRTOS)是一个单核 RTOS。为了支持各种多核 ESP 目标芯片,ESP-IDF 支持下述不同的 FreeRTOS 实现。

ESP-IDF FreeRTOS
^^^^^^^^^^^^^^^^

ESP-IDF FreeRTOS 是基于原生 FreeRTOS v10.4.3 的 FreeRTOS 实现,其中包含支持 SMP 的大量更新。ESP-IDF FreeRTOS 最多支持两个核(即双核 SMP),但在设计上对这种场景进行了优化。关于 ESP-IDF FreeRTOS 及具体更新内容,请参考 :doc:`freertos_idf` 文档。

.. note::

ESP-IDF FreeRTOS 是目前 ESP-IDF 默认的 FreeRTOS 实现。

.. only:: not esp32p4

.. _amazon_smp_freertos:

Amazon SMP FreeRTOS
^^^^^^^^^^^^^^^^^^^

Amazon SMP FreeRTOS 是由 Amazon 官方支持的 FreeRTOS SMP 实现。Amazon SMP FreeRTOS 能够支持 N 核,即双核以上。通过 :ref:`CONFIG_FREERTOS_SMP` 选项能够启用 Amazon SMP FreeRTOS。关于 Amazon SMP FreeRTOS 的更多细节,请参考 `官方 Amazon SMP FreeRTOS 文档 <https://freertos.org/zh-cn-cmn-s/symmetric-multiprocessing-introduction.html>`__。

.. warning::

Amazon SMP FreeRTOS 实现(及其在 ESP-IDF 中的移植)目前处于试验/测试状态,因此,可能会发生重大的行为变化及 API 变更。

配置
-------------

内核配置
^^^^^^^^^^^^^^^^^^^^

原生 FreeRTOS 要求移植工具和应用程序通过在 ``FreeRTOSConfig.h`` 头文件中添加各种 ``#define config...`` 宏定义来配置内核。原生 FreeRTOS 支持一系列内核配置选项,允许启用或禁用各种内核行为和功能。

**然而,对于 ESP-IDF 中的所有 FreeRTOS 移植,FreeRTOSConfig.h 头文件被视为私有文件,用户不得修改。** 由于该选项在 ESP-IDF 中是必选项或不被支持,``FreeRTOSConfig.h`` 中的大量内核配置选项均为硬编码。所有用户可配置的内核配置选项都在 ``Component Config/FreeRTOS/Kernel`` 下的 menuconfig 中。

关于用户可配置内核选项的完整列表,参见 :doc:`/api-reference/kconfig`。下列为常用的内核配置选项:

- :ref:`CONFIG_FREERTOS_UNICORE`:仅在 CPU0 上运行 FreeRTOS。注意,这 **不等同于运行原生 FreeRTOS。** 另外,此选项还可能影响除 :component:`freertos` 外其他组件的行为。关于在单核上运行 FreeRTOS 的更多内容,请参考 :ref:`freertos-smp-single-core` (使用 ESP-IDF FreeRTOS 时)或参考 Amazon SMP FreeRTOS 的官方文档,还可以在 ESP-IDF 组件中搜索 ``CONFIG_FREERTOS_UNICORE``。

.. only:: CONFIG_FREERTOS_UNICORE

.. note::
由于 {IDF_TARGET_NAME} 是一个单核 SoC,所以总是会启用 :ref:`CONFIG_FREERTOS_UNICORE` 配置。

- :ref:`CONFIG_FREERTOS_ENABLE_BACKWARD_COMPATIBILITY` 可以向后兼容某些 FreeRTOS 宏、类型或函数,这些宏、类型或函数已在 v8.0 及以上版本中弃用。

端口配置
^^^^^^^^^^^^^^^^^^

其他不属于内核配置的 FreeRTOS 相关配置选项都在 ``Component Config/FreeRTOS/Port`` 下的 menuconfig 中。这些选项可以配置以下内容:

- FreeRTOS 端口本身(如 tick 定时器选择,ISR 堆栈大小)
- 其他添加到 FreeRTOS 实现或端口的功能

使用 FreeRTOS
----------------

应用程序入口点
^^^^^^^^^^^^^^^^^^^^^^^

与原生 FreeRTOS 不同,在 ESP-IDF 中使用 FreeRTOS 的用户 **永远不应调用** :cpp:func:`vTaskStartScheduler` 和 :cpp:func:`vTaskEndScheduler`。相反,ESP-IDF 会自动启动 FreeRTOS。用户必须定义一个 ``void app_main(void)`` 函数作为用户应用程序的入口点,并在 ESP-IDF 启动时被自动调用。

- 通常,用户会从 ``app_main`` 中启动应用程序的其他任务。
- ``app_main`` 函数可以在任何时候返回(应用终止前)。
- ``app_main`` 函数由 ``main`` 任务调用。

.. _freertos_system_tasks:

后台任务
^^^^^^^^^^^^^^^^

在启动过程中,ESP-IDF 和 FreeRTOS 内核会自动创建多个在后台运行的任务,如下表所示。

.. list-table:: 启动过程创建任务列表
:widths: 10 75 5 5 5
:header-rows: 1

* - 任务名称
- 描述
- 堆栈大小
- 亲和性
- 优先级
* - 空闲任务 (``IDLEx``)
- 为每个 CPU 核创建并固定一个空闲任务 (``IDLEx``),其中 ``x`` 是 CPU 核的编号
- :ref:`CONFIG_FREERTOS_IDLE_TASK_STACKSIZE`
- Core x
- ``0``
* - FreeRTOS 定时器任务 (``Tmr Svc``)
- 如果应用程序调用了任何 FreeRTOS 定时器 API,FreeRTOS 会创建定时器服务或守护任务
- :ref:`CONFIG_FREERTOS_TIMER_TASK_STACK_DEPTH`
- Core 0
- :ref:`CONFIG_FREERTOS_TIMER_TASK_PRIORITY`
* - 主任务 (``main``)
- 简单调用 ``app_main`` 的任务在 ``app_main`` 返回时会自我删除
- :ref:`CONFIG_ESP_MAIN_TASK_STACK_SIZE`
- :ref:`CONFIG_ESP_MAIN_TASK_AFFINITY`
- ``1``
* - IPC 任务 (``ipcx``)
- 当 :ref:`CONFIG_FREERTOS_UNICORE` 为假时,为每个 CPU 核创建并固定一个 IPC 任务 (``ipcx``)。IPC 任务用于实现处理器间调用 (IPC) 功能
- :ref:`CONFIG_ESP_IPC_TASK_STACK_SIZE`
- Core x
- ``24``
* - ESP 定时器任务 (``esp_timer``)
- ESP-IDF 创建 ESP 定时器任务用于处理 ESP 定时器回调
- :ref:`CONFIG_ESP_TIMER_TASK_STACK_SIZE`
- Core 0
- ``22``

.. note::
注意,如果应用程序使用了其他 ESP-IDF 功能(如 Wi-Fi 或蓝牙),那么这些功能可能会在上表的任务之外创建自己的后台任务。

FreeRTOS 附加功能
------------------

ESP-IDF 还为 FreeRTOS 提供了一些补充功能,如环形缓冲区、ESP-IDF 风格的 Tick 和 Idle 钩子、以及 TLSP 删除回调。要了解更多信息,请参见 :doc:`freertos_additions`。

.. _freertos-heap:

FreeRTOS 堆
-------------

原生 FreeRTOS 自带 `堆实现选择 <https://www.freertos.org/a00111.html>`_,然而 ESP-IDF 已经实现了自己的堆(参见 :doc:`/api-reference/system/mem_alloc`),因此不使用原生 FreeRTOS 的堆实现。ESP-IDF 中的所有 FreeRTOS 端口都将 FreeRTOS 内存分配或释放调用(例如 ``pvPortMalloc()`` 和 ``pvPortFree()``)映射到 ESP-IDF 堆 API(即 :cpp:func:`heap_caps_malloc` 和 :cpp:func:`heap_caps_free`)。然而 FreeRTOS 端口可以确保 FreeRTOS 分配的所有动态内存都放在内部内存中。

.. note::
如果希望将 FreeRTOS 任务或对象放在外部内存中,可以使用以下方法:

- 使用一个 ``...CreateWithCaps()`` API,如 :cpp:func:`xTaskCreateWithCaps` 和 :cpp:func:`xQueueCreateWithCaps` 来分配任务或对象(参见 :ref:`freertos-idf-additional-api` 获取更多详细信息)。
- 使用 :cpp:func:`heap_caps_malloc` 为这些对象手动分配外部内存,然后使用 FreeRTOS 的一个 ``...CreateStatic()`` 函数从分配的内存中创建对象。

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