CubeMX FreeRTOS(cmsis os)函数API一览 （附可以在中断中调用的API）
CubeMX生成FreeRTOS工程以后，因为兼容多个RTOS的缘故，对很多函数的API做了封装，刚开始接触，不是很清楚这些API的资料在哪找，在此列出。
实际使用时，对照下面的官方的API介绍，会发现这个CMSIS RTOS的API太少了，很多FreeRTOS原来的功能，例如：获取任务栈空间剩余量，复位消息队列等等API都没有相应的说明。
因为资料少，刚开始摸索很不解，逐渐使用发现，FreeRTOS本来的API是可以直接使用的，实际开发中我也是混着用，因为CubeMX封装以后的做了一些小处理，例如一些API的中断保护版本都被CMSIS OS整合到一起了，使用时不必再区分是否在中断里，还是很方便的。
一些下面说明文档中没有的API就使用FreeRTOS本身的了。
以下所有资料来源于cmsis rtos官方说明文档，在keil5本地就有：
Function Overview
函数一览：
Kernel Information and Control
osKernelInitialize : Initialize the RTOS kernel.
osKernelStart : Start the RTOS kernel.
osKernelRunning : Query if the RTOS kernel is running.
osKernelSysTick : Get RTOS kernel system timer counter.
osKernelSysTickFrequency : RTOS kernel system timer frequency in Hz.
osKernelSysTickMicroSec : Convert microseconds value to RTOS kernel system timer value.
Thread Management
osThreadCreate : Start execution of a thread function.
osThreadTerminate : Stop execution of a thread function.
osThreadYield : Pass execution to next ready thread function.
osThreadGetId : Get the thread identifier to reference this thread.
osThreadSetPriority : Change the execution priority of a thread function.
osThreadGetPriority : Obtain the current execution priority of a thread function.
Generic Wait Functions
osDelay : Wait for a specified time.
osWait : Wait for any event of the type Signal, Message, or Mail.(*)
Timer Management
osTimerCreate : Define attributes of the timer callback function.
osTimerStart : Start or restart the timer with a time value.
osTimerStop : Stop the timer.
osTimerDelete : Delete a timer.
Signal Events
osSignalSet : Set signal flags of a thread.
osSignalClear : Reset signal flags of a thread.
osSignalWait : Suspend execution until specific signal flags are set.
Mutexes
osMutexCreate : Define and initialize a mutex.
osMutexWait : Obtain a mutex or Wait until it becomes available.
osMutexRelease : Release a mutex.
osMutexDelete : Delete a mutex.
Semaphores
osSemaphoreCreate : Define and initialize a semaphore.
osSemaphoreWait : Obtain a semaphore token or Wait until it becomes available.
osSemaphoreRelease : Release a semaphore token.
osSemaphoreDelete : Delete a semaphore.
Memory Pool
osPoolCreate : Define and initialize a fix-size memory pool.
osPoolAlloc : Allocate a memory block.
osPoolCAlloc : Allocate a memory block and zero-set this block.
osPoolFree : Return a memory block to the memory pool.
Message Queue
osMessageCreate : Define and initialize a message queue.
osMessagePut : Put a message into a message queue.
osMessageGet : Get a message or suspend thread execution until message arrives.
Mail Queue
osMailCreate : Define and initialize a mail queue with fix-size memory blocks.
osMailAlloc : Allocate a memory block.
osMailCAlloc : Allocate a memory block and zero-set this block.
osMailPut : Put a memory block into a mail queue.
osMailGet : Get a mail or suspend thread execution until mail arrives.
osMailFree : Return a memory block to the mail queue.
RTX Specific Functions
os_idle_demon : System thread running when no other thread is ready to run.
os_suspend : Suspend the RTX task scheduler.
os_resume : Resume the RTX task scheduler.
os_tick_init : Initialize an alternative hardware timer as RTX kernel timer.
os_tick_val : Get alternative hardware timer's current value.
os_tick_ovf : Get alternative hardware timer's overflow flag.
os_tick_irqack : Acknowledge alternative hardware timer interrupt.
os_error : Called when a runtime error is detected.
The following CMSIS-RTOS functions can be called from threads and Interrupt Service Routines (ISR):
下面的函数支持在中断中调用：
osKernelRunning 查询内核是否正在运行
osSignalSet 创建信号量
osSemaphoreRelease 释放信号量令牌
osPoolAlloc, osPoolCAlloc, osPoolFree 分配一个内存池 分配且清零一个内存池 释放内存池
osMessagePut, osMessageGet 将消息放入消息队列 获取消息队列
osMailAlloc, osMailCAlloc, osMailGet, osMailPut, osMailFree 分配内存块 分配一个内存块并对这个块清零 获取邮件或挂起线程执行，直到邮件到达 将内存块放入邮件队列 将内存块返回到邮件队列