[Zephyr] Workqueue

https://academy.nordicsemi.com/courses/nrf-connect-sdk-fundamentals/lessons/lesson-7-multithreaded-applications/topic/exercise-3-7/

Exercise 3 - Nordic Developer Academy

 

https://docs.zephyrproject.org/apidoc/latest/group__workqueue__apis.html

Zephyr API Documentation: Work Queue APIs

 

 

#include <zephyr.h>
#include <sys/printk.h>
#include <kernel.h>
#include <kernel_structs.h>
#include <string.h>

#define THREAD0_STACKSIZE       512
#define THREAD1_STACKSIZE       512
#define WORQ_THREAD_STACK_SIZE  512

// 스레드 우선 순위 정의, workqueue를 가장 낮게 줌
#define THREAD0_PRIORITY 2 
#define THREAD1_PRIORITY 3
#define WORKQ_PRIORITY   4

// workqueue가 쓸 스택 정의
static K_THREAD_STACK_DEFINE(my_stack_area, WORQ_THREAD_STACK_SIZE);

// workqueue 구조체 정의
static struct k_work_q offload_work_q = {0};


// 긴급하지 않은 작업
static inline void emulate_work()
{
	for(volatile int count_out = 0; count_out < 150000; count_out ++);
}

// k_work와 이름을 가짐, workqueue로 이전할 work
struct work_info {
    struct k_work work;
    char name[25];
} my_work;

// 이전 함수
void offload_function(struct k_work *work_tem)
{
	emulate_work();
}

//나중에 main thread로
void thread0(void)
{
    uint64_t time_stamp;
    int64_t delta_time;
    
    //workqueue 시작
    //work item를 초기화하고 핸들러 함수에 연결
	k_work_queue_start(&offload_work_q, my_stack_area,
					K_THREAD_STACK_SIZEOF(my_stack_area), WORKQ_PRIORITY,
					NULL);
                    
	strcpy(my_work.name, "Thread0 emulate_work()");
	k_work_init(&my_work.work, offload_function);
    
    //thread0 loop
    while (1) {
        time_stamp = k_uptime_get();
		
        //work를 workqueue로 넘겨서 처리
        k_work_submit_to_queue(&offload_work_q, &my_work.work);
        
        delta_time = k_uptime_delta(&time_stamp);
        printk("thread0 yielding this round in %lld ms\n", delta_time);
        k_msleep(20);
    }   
}

//thread1 진입 함수
void thread1(void)
{
    uint64_t time_stamp;
    int64_t delta_time;

	//thread1 loop
    while (1) {
        time_stamp = k_uptime_get();
        emulate_work();
        delta_time = k_uptime_delta(&time_stamp);

        printk("thread1 yielding this round in %lld ms\n", delta_time);
        k_msleep(20);
    }   
}

K_THREAD_DEFINE(thread0_id, THREAD0_STACKSIZE, thread0, NULL, NULL, NULL,
		THREAD0_PRIORITY, 0, 0);
K_THREAD_DEFINE(thread1_id, THREAD1_STACKSIZE, thread1, NULL, NULL, NULL,
		THREAD1_PRIORITY, 0, 0);