一、内核基础组件
- 优先级队列
概述
提供了基于优先级的队列管理。环形队列的入队出队规则是先入队的先出队（first in, first out），优先级队列的出队顺序是按照优先级来的，优先级较高的元素先出队。
API讲解
编程实例
1、编写main.c示例代码：
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usart.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "cmsis_os.h"
#include "stdio.h"
#include "tos_k.h"
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
/*
此案例展示了优先级队列的出队规则：依次入队优先级为5、4、3、2、1的元素，出队时的顺序是按照优先级来的，也就是按优先级从高到低（数值越大，优先级越小），依次出队优先级为1、2、3、4、5元素。
*/
#define STK_SIZE_TASK_DEMO 512
#define PRIO_TASK_DEMO 4
k_stack_t stack_task_demo[STK_SIZE_TASK_DEMO];
k_task_t task_demo;
typedef struct item_st {
int a;
int b;
int c;
} item_t;
#define PRIO_QUEUE_ITEM_MAX 5
uint8_t ring_q_buffer[PRIO_QUEUE_ITEM_MAX * sizeof(item_t)];
uint8_t mgr_pool[TOS_PRIO_Q_MGR_ARRAY_SIZE(PRIO_QUEUE_ITEM_MAX)];
k_prio_q_t prio_q;
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
void entry_task_demo(void *arg)
{
k_err_t err;
int i = 0;
item_t item;
k_prio_t prio;
size_t item_size;
tos_prio_q_create(&prio_q, mgr_pool, ring_q_buffer, PRIO_QUEUE_ITEM_MAX, sizeof(item_t));
for (i = PRIO_QUEUE_ITEM_MAX; i > 0; --i) {
printf("enqueue: %d %d %d\n", i, i, i);
item.a = i;
item.b = i;
item.c = i;
err = tos_prio_q_enqueue(&prio_q, &item, sizeof(item_t), i);
if (err != K_ERR_NONE) {
printf("should never happen\n");
}
}
err = tos_prio_q_enqueue(&prio_q, &item, sizeof(item_t), i);
if (err == K_ERR_PRIO_Q_FULL) {
printf("priority queue is full: %s\n", tos_prio_q_is_full(&prio_q) ? "TRUE" : "FALSE");
} else {
printf("should never happen\n");
}
for (i = 0; i < PRIO_QUEUE_ITEM_MAX; ++i) {
err = tos_prio_q_dequeue(&prio_q, &item, &item_size, &prio);
if (err == K_ERR_NONE) {
printf("dequeue: %d %d %d, prio: %d\n", item.a, item.b, item.c, prio);
} else {
printf("should never happen\n");
}
}
err = tos_prio_q_dequeue(&prio_q, &item, &item_size, &prio);
if (err == K_ERR_PRIO_Q_EMPTY) {
printf("priority queue is empty: %s\n", tos_prio_q_is_empty(&prio_q) ? "TRUE" : "FALSE");
} else {
printf("should never happen\n");
}
}
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_USART1_UART_Init();
/* USER CODE BEGIN 2 */
tos_knl_init();
(void)tos_task_create(&task_demo, "demo", entry_task_demo, NULL,
PRIO_TASK_DEMO, stack_task_demo, STK_SIZE_TASK_DEMO,
0);
tos_knl_start();
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
2、运行效果：
源码链接：
