邝坚_北邮嵌入式实验报告

1、嵌入式系统期末实验一、实验要求题目：支持消息驱动模式的实时软件框架目的：在充分理解嵌入式处理器特点、RTOS 及强实时嵌入式系统软件设计规范的基础上，构建自己的实时系统软件框架基本功能，并在其上自拟应用（如部分模拟TCP 的C/S两端通信流程），测试软件框架的相关功能。环境：VxWorks 的VxSim 仿真环境或2440(ARM920T)内容：必选功能：1. 消息驱动的Task 统一框架，包含统一消息格式定义及使用规范；2. 支持消息驱动模式的软定时器的机制；3. Task 启动同步功能；4. 体现前次实验中实现的自定义内存管理机制，最大限度降低外部碎片对系统可靠性的威胁。可选功能（加分）：

2、其它有利于实时处理的有效机制，如：无信号量（互斥）支持的临界资源访问方式，zero copy 等；二、实现的功能1. 消息驱动的Task 统一框架，包含统一消息格式定义及使用规范；STATUS Task()Initialization(MBox, Data Structure, Timer, etc.)ForeverMsgReceiveIf()else if()typedef struct _MESSAGE int mType;/* 消息类型 0:timer->client *1:client->server 2:server->client*/ int mSendId; /

3、* 发送任务的MESSAGE ID */ int mRecvId; /* 接收任务的MESSAGE ID */ int mData; /* 消息中传递的数据 */MESSAGE;2. 支持消息驱动模式的软定时器的机制；/* timer(id)向客户端消息队列定时发送的定时器*/STATUS timer(int id) MESSAGE* txMsg;/* 用于从消息队列中接收消息 */ int tick;/*创建一个定时，用于提醒发送者任务定时发送消息*/ tick=sysClkRateGet(); semTake(semSynStart,WAIT_FOREVER); FOREVER taskD

4、elay(int)(tick*DELAY_SECOND); txMsg = (MESSAGE*)memMalloc(MAX_MSG_LEN); txMsg->mType = 0; txMsg->mSendId = MID_TIMER(id); txMsg->mRecvId = MID_CLIENT(id); txMsg->mData = 0; printf("tTimer%d send message to tClient%d!n",id,id);if(msgQSend(msgQIdClientid,(char*)&txMsg,MAX_MSG

5、_LEN,WAIT_FOREVER,MSG_PRI_NORMAL) = ERROR ) return (ERROR); return (OK);3. Task 启动同步功能；由manager()创建的任务优先级最高，先创建timer()、server()、client()的任务，让他们都在等待信号量semSynStart而被阻塞，最后创建manager()的任务，占据CPU，等待其他所有任务都被阻塞，解锁所有等待信号量的任务，让它们同时启动。/* progStart()启动实例程序*/STATUS progStart(void)int id; /* 用来区分不同的定时器或者客户任务 */mal

6、locPtr=&sysMalloc;mallocPtr->frontBlock = 0;initialPtr = initial();tidServer = tidManager = 0;for (id = 0; id < NUM_CLIENT; id+)tidClientid = 0; for (id = 0; id < NUM_TIMER; id+) tidTimerid = 0; /* 创建消息队列 */ msgQIdServer = msgQCreate(MAX_MSGS, MAX_MSG_LEN, MSG_Q_FIFO|MSG_Q_EVENTSEND_ERR

7、_NOTIFY); if (msgQIdServer = NULL) return (ERROR); for (id = 0; id < NUM_CLIENT; id+) msgQIdClientid = msgQCreate(MAX_MSGS, MAX_MSG_LEN, MSG_Q_FIFO|MSG_Q_EVENTSEND_ERR_NOTIFY); if (msgQIdClientid = NULL) return (ERROR); semSynStart = semBCreate(SEM_Q_FIFO | SEM_EVENTSEND_ERR_NOTIFY,SEM_EMPTY); se

8、mMalloc = semBCreate(SEM_Q_PRIORITY,SEM_FULL); semFree = semBCreate(SEM_Q_PRIORITY,SEM_FULL); /* 创建任务 */ tidServer = taskSpawn("tServer", 220, 0, STACK_SIZE,(FUNCPTR)server,0,0,0,0,0,0,0,0,0,0); for (id = 0; id < NUM_CLIENT; id+) char tempName20; sprintf(tempName, "tClient%d",

9、 id); tidClientid = taskSpawn(tempName, 210, 0, STACK_SIZE, (FUNCPTR)client,id,0,0,0,0,0,0,0,0,0); for (id = 0; id < NUM_TIMER; id+) char tempName20; sprintf(tempName, "tTimer%d", id); tidTimerid = taskSpawn(tempName, 230, 0, STACK_SIZE, (FUNCPTR)timer,id,0,0,0,0,0,0,0,0,0); tidManager

10、= taskSpawn("tMannager", 200, 0, STACK_SIZE, (FUNCPTR)manager,0,0,0,0,0,0,0,0,0,0); printf("programe start!n"); return (OK);/* manager() 管理进程，实现task同步*/STATUS manager() int id; while(taskIsSuspended(tidServer) | taskIsReady(tidServer) taskDelay(10); for (id = 0; id < NUM_CLIEN

11、T; id+) while(taskIsSuspended(tidClientid) | taskIsReady(tidClientid) taskDelay(10); for (id = 0; id < NUM_TIMER; id+) while(taskIsSuspended(tidTimerid) | taskIsReady(tidTimerid) taskDelay(10); semFlush(semSynStart); return (OK);/* server()处理来自各个客户任务的消息*/STATUS server(void) semTake(semSynStart,WA

12、IT_FOREVER); FOREVER return (OK);/* timer(id)向客户端定时发送的定时器*/STATUS timer(int id) semTake(semSynStart,WAIT_FOREVER); FOREVER return (OK);/*client(id)向服务器任务发请求消息*/STATUS client(int id) semTake(semSynStart,WAIT_FOREVER); FOREVER return (OK);4. 体现前次实验中实现的自定义内存管理机制，最大限度降低外部碎片对系统可靠性的威胁。静态内存的数据结构为单链表，采用头插法，

13、申请内存时，修改firstavailable另其指向第二块，将firstavailable指向的头块取出，回收内存时，将回收的块的frontBlock指向第一块，修改firstavailable另其指向回收的块，将回收的块作为第一块，数据结构如下所示：静态分配了含有32个16B块的内存池和含有16个256B块的内存池，如果申请的内存大于256B，调用系统malloc。/*initial() 初始化内存池*/pool* initial(void)int i;pool* mem;pool* poolPtr;poolHead* poolHeadPtr;blockHead* blockHeadPtr;

14、mem=(pool*)malloc(6000);/*分配6000B内存作为内存池*/ /*初始化pool*/poolPtr = (pool*)mem;poolPtr->poolNum = 2;poolPtr->pool = (poolHead*)(char*)mem + sizeof(pool); /*pool指向申请内存区尾*/ /*初始化pool 1 该内存池分配大小为16B的内存*/poolHeadPtr = (poolHead*)(char*)mem + sizeof(pool);/*初始化内存池的首地址*/poolHeadPtr->available = 32; /

15、*初始化可用块数32*/poolHeadPtr->blockSize = 16; /*块大小16B*/blockHeadPtr = (blockHead*)(char*)poolHeadPtr+sizeof(poolHead);/*初始化块的首地址*/poolHeadPtr->firstavailable = blockHeadPtr; /*初始化第一块可用块的地址*/poolHeadPtr->next= (poolHead*)(char*)poolHeadPtr + sizeof(poolHeadPtr) + 32*(sizeof(blockHead)+16); /*nex

16、t指向第二个内存池 */ blockHeadPtr->poolId =1;blockHeadPtr->frontBlock = 0; for(i=1;i<32;i+) /*将该内存池划分为32个容量16B的内存块*/blockHeadPtr=(blockHead*)(char*)blockHeadPtr + (sizeof(blockHead)+16); /*块的首址移动16加结构体的开销长度*/blockHeadPtr->poolId = 1; /* pool号为1，表示他是16B容量的*/blockHeadPtr->frontBlock = poolHeadP

17、tr->firstavailable; /* 当前首个可用块地址赋给frontBlock */poolHeadPtr->firstavailable = blockHeadPtr; /* 求下一首个可用块地址*/*初始化pool 2 该内存池分配大小为256B的内存*/poolHeadPtr = poolHeadPtr->next;poolHeadPtr->available = 16; /*初始化可用块数16*/poolHeadPtr->blockSize = 256; /*块大小256*/blockHeadPtr = (blockHead*)(char*)po

18、olHeadPtr+sizeof(poolHead);poolHeadPtr->firstavailable = blockHeadPtr;poolHeadPtr->next = 0; blockHeadPtr->poolId =2;blockHeadPtr->frontBlock = 0;for(i=1;i<16;i+) /*将该内存池划分为16个容量256B的内存块*/blockHeadPtr=(blockHead*)(char*)blockHeadPtr + (sizeof(blockHead)+256);blockHeadPtr->poolId =

19、2; /* pool号为2，表示他是256B容量的*/blockHeadPtr->frontBlock = poolHeadPtr->firstavailable;poolHeadPtr->firstavailable = blockHeadPtr;return (pool*)mem;/*memMalloc() 分配内存*/void* memMalloc(int Size)void* mem;poolHead* poolHeadPtr;blockHead* blockHeadPtr;semTake(semMalloc,WAIT_FOREVER);poolHeadPtr = i

20、nitialPtr->pool;if(Size <= 16)&&(poolHeadPtr->available != 0) /*长度小于16时，分配长度为16的内存空间*/blockHeadPtr = poolHeadPtr->firstavailable; /*首个可用块地址赋给分配块的首地址*/poolHeadPtr->firstavailable = blockHeadPtr->frontBlock; /*改变下一第一可用块的地址*/poolHeadPtr->available -; /*可用块数减一*/semGive(semMa

21、lloc); return (void*)(char*)blockHeadPtr + sizeof(blockHead); /*分配内存时加入块头开销*/else if(Size <= 256)&&(poolHeadPtr->next)->available != 0) /*长度大于16小于256时，分配长度为256的内存空间*/blockHeadPtr = (poolHeadPtr->next)->firstavailable;(poolHeadPtr->next)->firstavailable = blockHeadPtr->

22、;frontBlock; (poolHeadPtr->next)->available -; semGive(semMalloc);return (void*)(char*)blockHeadPtr + sizeof(blockHead);else/*其他情况用系统的内存分配函数malloc分配*/printf("nWarning : Too large for blocks or the blocks are exhausted n");mem = malloc(Size); /*采用系统函数malloc（）分配内存*/blockHeadPtr = (bloc

23、kHead*)mem;blockHeadPtr->poolId = (initialPtr->poolNum +1);blockHeadPtr->frontBlock = mallocPtr;mallocPtr = blockHeadPtr;semGive(semMalloc);return (void*)(char*)blockHeadPtr + sizeof(blockHead);/*memFree() 释放内存空间*/void memFree(void* dataPtr)char* mem= (char*) dataPtr;poolHead* poolHeadPtr;b

24、lockHead* blockHeadPtr;semTake(semFree,WAIT_FOREVER);poolHeadPtr = initialPtr->pool; /*恢复内存池首址*/blockHeadPtr = (blockHead*)(char*)mem - sizeof(blockHead); /*恢复内存块首址*/if(blockHeadPtr->poolId = 1) /*释放16B的内存块*/ blockHeadPtr->frontBlock = poolHeadPtr->firstavailable; /*恢复frontBlock地址*/poolH

25、eadPtr->firstavailable = blockHeadPtr; /*恢复第一可用块地址*/poolHeadPtr->available+; /*恢复可用块数*/else if(blockHeadPtr->poolId = 2)/*释放256B的内存块*/blockHeadPtr->frontBlock = (poolHeadPtr->next)->firstavailable;(poolHeadPtr->next)->firstavailable = blockHeadPtr;(poolHeadPtr->next)->available +;else /*释放由系统分配的内存块*/blockHeadPtr = mallocPtr;mallocPtr = blockHeadPtr->frontBlock;free(char*)mem - sizeof(blockHead);semGive(semFree);return;/*memD