producer_consumer.c

/* * Copyright (c) 2006-2018, RT-Thread Development Team * * SPDX-License-Identifier: Apache-2.0 * * Change Logs: * Date Author Notes * 2018-08-24 yangjie the first version *//* * 程序清单：生产者消费者例子 * * 这个例子中将创建两个线程用于实现生产者消费者问题 *（1）生产者线程将cnt值每次加1并循环存入array数组的5个成员内； *（2）消费者线程将生产者中生产的数值打印出来，并累加求和 */#include <rtthread.h>#define THREAD_PRIORITY 6#define THREAD_STACK_SIZE 512#define THREAD_TIMESLICE 5/* 定义最大5个元素能够被产生 */#define MAXSEM 5/* 用于放置生产的整数数组 */rt_uint32_t array[MAXSEM];/* 指向生产者、消费者在array数组中的读写位置 */static rt_uint32_t set, get;/* 指向线程控制块的指针 */static rt_thread_t producer_tid = RT_NULL;static rt_thread_t consumer_tid = RT_NULL;struct rt_semaphore sem_lock;struct rt_semaphore sem_empty, sem_full;/* 生产者线程入口 */void producer_thread_entry(void *parameter){ int cnt = 0; /* 运行10次 */ while (cnt < 10) { /* 获取一个空位 */ rt_sem_take(&sem_empty, RT_WAITING_FOREVER); /* 修改array内容，上锁 */ rt_sem_take(&sem_lock, RT_WAITING_FOREVER); array[set % MAXSEM] = cnt + 1; rt_kprintf("the producer generates a number: %d\n", array[set % MAXSEM]); set++; rt_sem_release(&sem_lock); /* 发布一个满位 */ rt_sem_release(&sem_full); cnt++; /* 暂停一段时间 */ rt_thread_mdelay(20); } rt_kprintf("the producer exit!\n");}/* 消费者线程入口 */void consumer_thread_entry(void *parameter){ rt_uint32_t sum = 0; while (1) { /* 获取一个满位 */ rt_sem_take(&sem_full, RT_WAITING_FOREVER); /* 临界区，上锁进行操作 */ rt_sem_take(&sem_lock, RT_WAITING_FOREVER); sum += array[get % MAXSEM]; rt_kprintf("the consumer[%d] get a number: %d\n", (get % MAXSEM), array[get % MAXSEM]); get++; rt_sem_release(&sem_lock); /* 释放一个空位 */ rt_sem_release(&sem_empty); /* 生产者生产到10个数目，停止，消费者线程相应停止 */ if (get == 10) break; /* 暂停一小会时间 */ rt_thread_mdelay(50); } rt_kprintf("the consumer sum is: %d\n", sum); rt_kprintf("the consumer exit!\n");}int producer_consumer(void){ set = 0; get = 0; /* 初始化3个信号量 */ rt_sem_init(&sem_lock, "lock", 1, RT_IPC_FLAG_FIFO); rt_sem_init(&sem_empty, "empty", MAXSEM, RT_IPC_FLAG_FIFO); rt_sem_init(&sem_full, "full", 0, RT_IPC_FLAG_FIFO); /* 创建生产者线程 */ producer_tid = rt_thread_create("producer", producer_thread_entry, RT_NULL, THREAD_STACK_SIZE, THREAD_PRIORITY - 1, THREAD_TIMESLICE); if (producer_tid != RT_NULL) rt_thread_startup(producer_tid); /* 创建消费者线程 */ consumer_tid = rt_thread_create("consumer", consumer_thread_entry, RT_NULL, THREAD_STACK_SIZE, THREAD_PRIORITY + 1, THREAD_TIMESLICE); if (consumer_tid != RT_NULL) rt_thread_startup(consumer_tid); return 0;}/* 导出到 msh 命令列表中 */MSH_CMD_EXPORT(producer_consumer, producer_consumer sample);