山東大學(xué)操作系統(tǒng)實驗報告4進程同步實驗

計算機科學(xué)與技術(shù)學(xué)院實驗報告實驗題目：實驗四、進程同步實驗學(xué)號：日期：20120409班級：計基地12姓名：實驗?zāi)康模杭由顚Σl(fā)協(xié)作進程同步與互斥概念的理解，觀察和體驗并發(fā)進程同步與互斥操作的效果，分析與研究經(jīng)典進程同步與互斥問題的實際解決方案。了解Linux系統(tǒng)中IPC進程同步工具的用法，練習并發(fā)協(xié)作進程的同步與互斥操作的編程與調(diào)試技術(shù)。實驗內(nèi)容：抽煙者問題。假設(shè)一個系統(tǒng)中有三個抽煙者進程，每個抽煙者不斷地卷煙并抽煙。抽煙者卷起并抽掉一顆煙需要有三種材料：煙草、紙和膠水。一個抽煙者有煙草，一個有紙，另一個有膠水。系統(tǒng)中還有兩個供應(yīng)者進程，它們無限地供應(yīng)所有三種材料，但每次僅輪流提供三種材料中的兩種。得到缺失的兩種材料的抽煙者在卷起并抽掉一顆煙后會發(fā)信號通知供應(yīng)者，讓它繼續(xù)提供另外的兩種材料。這一過程重復(fù)進行。請用以上介紹的IPC同步機制編程，實現(xiàn)該問題要求的功能。硬件環(huán)境：處理器：Intel?Core?X4圖形：Intel?SandybridgeMobilex86/MMX/SSE2內(nèi)存：4G操作系統(tǒng)：32位磁盤：20.1GB軟件環(huán)境：ubuntu13.04實驗步驟：新建定義了producer和consumer共用的IPC函數(shù)原型和變量的ipc.h文件。新建ipc.c文件，編寫producer和consumer共用的IPC的具體相應(yīng)函數(shù)。新建Producer文件，首先定義producer的一些行為，利用系統(tǒng)調(diào)用，建立共享內(nèi)存區(qū)域，設(shè)定其長度并獲取共享內(nèi)存的首地址。然后設(shè)定生產(chǎn)者互斥與同步的信號燈，并為他們設(shè)置相應(yīng)的初值。當有生產(chǎn)者進程在運行而其他生產(chǎn)者請求時，相應(yīng)的信號燈就會阻止他，當共享內(nèi)存區(qū)域已滿時，信號等也會提示生產(chǎn)者不能再往共享內(nèi)存中放入內(nèi)容。新建Consumer文件，定義consumer的一些行為，利用系統(tǒng)調(diào)用來創(chuàng)建共享內(nèi)存區(qū)域，并設(shè)定他的長度并獲取共享內(nèi)存的首地址。然后設(shè)定消費者互斥與同步的信號燈，并為他們設(shè)置相應(yīng)的初值。當有消費進程在運行而其他消費者請求時，相應(yīng)的信號燈就會阻止它，當共享內(nèi)存區(qū)域已空時，信號等也會提示生產(chǎn)者不能再從共享內(nèi)存中取出相應(yīng)的內(nèi)容。運行的消費者應(yīng)該與相應(yīng)的生產(chǎn)者對應(yīng)起來，只有這樣運行結(jié)果才會正確。結(jié)論分析與體會：實現(xiàn)方式：Consumer:#include"ipc.h"intmain(intargc,char*argv[]){intrate=3;intconsumerid二atoi(argv[1]);buff_h=101;buff_number=1;cget_h=103;cget_number=1;shm_flg=IPC_CREAT|0644;buff_ptr=(char*)set_shm(buff_h,buff_number,shm_flg);cget_ptr=(int*)set_shm(cget_h,cget_number,shm_flg);prod_h=201;pmtx_h=202;cons_h=301;cmtx_h=302;sem_flg=IPC_CREAT|0644;sem_val=buff_number;prod_sem=set_sem(prod_h,sem_val,sem_flg);sem_val=0;cons_sem=set_sem(cons_h,sem_val,sem_flg);sem_val=1;cmtx_sem=set_sem(cmtx_h,sem_val,sem_flg);if(consumerid==0)*cget_ptr=0;while(1){if(buff_ptr[0]-'A'=consumerid){down(cons_sem);down(cmtx_sem);sleep(rate);if(buff_ptr[0]='A'){printf("%dTheconsumerhasglue.\nTheconsumergetstobaccoandpaper\n",getpid());}if(buff_ptr[0]='B'){printf("%dTheconsumerhaspaper.\nTheconsumergetstobaccoandglue\n",getpid());}if(buff_ptr[0]='C'){printf("%dTheconsumerhastobacco.\nTheconsumergetsglueandpaper\n",getpid());}*cget_ptr=(*cget_ptr+1);if(*cget_ptr%2==0)buff_ptr[0]='D';elsebuff_ptr[0]='E';up(cmtx_sem);up(prod_sem);}}returnEXIT_SUCCESS;}Producer:#include"ipc.h"intmain(intargc,char*argv[]){intrate=3;intproducerid二atoi(argv[1]);buff_h=101;buff_number=1;pput_h=102;pput_number=1;shm_flg=IPC_CREAT|0644;buff_ptr=(char*)set_shm(buff_h,buff_number,shm_flg);pput_ptr=(int*)set_shm(pput_h,pput_number,shm_flg);prod_h=201;pmtx_h=202;cons_h=301;cmtx_h=302;sem_flg=IPC_CREAT|0644;sem_val=buff_number;prod_sem=set_sem(prod_h,sem_val,sem_flg);sem_val=0;cons_sem=set_sem(cons_h,sem_val,sem_flg);sem_val=1;pmtxsem=setsem(pmtxh,semval,semflg);if(producerid==0){buff_ptr[0]='D';*pput_ptr=0;}while(1){if(buff_ptr[0]-'D'=producerid){down(prod_sem);down(pmtx_sem);*pput_ptr=(*pput_ptr+1)%3;if(*pput_ptr==0){buff_ptr[0]='A';printf("%dTheproducergivestobaccoandpaper\n",getpid());}if(*pput_ptr==1){buff_ptr[0]=printf("%d'B';Theproducergivestobaccoandglue\n",getpid());}if(*pput_ptr==2){buff_ptr[0]='C';printf("%dTheproducergivesglueandpaper\n",getpid());}sleep(rate);up(pmtx_sem);up(cons_sem);}}returnEXIT_SUCCESS;}Ipc.h：#include"ipc.h"intget_ipc_id(char*proc_file,h_th){FILE*pf;intm,n;charline[BUFSZ],colum[BUFSZ];if((pf=fopen(proc_file,"r"))=NULL){perror("Procfilenotopen");exit(EXIT_FAILURE);}fgets(line,BUFSZ,pf);while(!feof(pf)){m=n=0;fgets(line,BUFSZ,pf);while(line[m]='')m++;while(line[m]!='')colum[n++]=line[m++];colum[n]='\0';if(atoi(colum)!=h)continue;n=0;while(line[m]='')m++;while(line[m]!='')colum[n++]=line[m++];colum[n]='\0';m=atoi(colum);fclose(pf);returnm;}fclose(pf);return-1;}intdown(intsem_id){structsembufbuf;buf.sem_op=-1;buf.sem_number=0;buf.sem_flg=SEM_UNDO;if((semop(sem_id,&buf,1))<0){perror("downerror");exit(EXIT_FAILURE);}returnEXIT_SUCCESS;}intup(intsem_id){structsembufbuf;buf.sem_op=1;buf.sem_number=0;buf.sem_flg=SEM_UNDO;if((semop(sem_id,&buf,1))<0){perror("uperror");exit(EXIT_FAILURE);returnEXIT_SUCCESS;}intset_sem(h_tsem_h,intsem_val,intsem_flg){intsem_id;Sem_unssem_arg;if((sem_id=get_ipc_id("/proc/sysvipc/sem",sem_h))<0){if((sem_id=semget(sem_h,1,sem_flg))<0){perror("semaphorecreateerror");exit(EXIT_FAILURE);}sem_arg.val=sem_val;if(semctl(sem_id,0,SETVAL,sem_arg)<0){perror("semaphoreseterror");exit(EXIT_FAILURE);}}returnsem_id;}char*set_shm(h_tshm_h,intshm_number,intshm_flg){intm,shm_id;char*shm_buf;if((shm_id=get_ipc_id("/proc/sysvipc/shm",shm_h))<0){if((shm_id=shmget(shm_h,shm_number,shm_flg))<0){perror("shareMemoryseterror");exit(EXIT_FAILURE);}if((shm_buf=(char*)shmat(shm_id,0,0))<(char*)0){perror("getshareMemoryerror");exit(EXIT_FAILURE);}for(m=0;m<shm_number;m++)shm_buf[m]=0;}—if((shm_buf=(char*)shmat(shm_id,0,0))<(char*)0){perror("getshareMemoryerror");exit(EXIT_FAILURE);}returnshm_buf;}intsetmsq(htmsqh,intmsqflg){

intmsq_id;if((msq_id=get_ipc_id("/proc/sysvipc/msg",msq_h))<0){if((msq_id=msgget(msq_h,msq_flg))<0){perror("messageQueueseterror");exit(EXIT_FAILURE);}}returnmsq_id;}實驗結(jié)果:ITkunikun-LcnovoideaPad-Y471A:-/lab4likunglikun-Lenovo-IdedPdd-Y471A:~Scdldb43320The33ZOThe3329The3329The33ZBThe33zaTheThe33ZOThesszaThe3328The3320The33zaThe3328The33源The33zaThe3328Theproducerprodu匚如producerproducerproduce「producerproducerproducerproducerproducerproducerproducerproducerproducerproducerproducerItkungltkun-Lenovo-ldeaPad-V471A：~/lab4$./prodjcer0givestobaccoandgluegivesglueandpapergtvestobaccoandgluegivestobaccoandpapergtve53320The33ZOThe3329The3329The33ZBThe33zaTheThe33ZOThesszaThe3328The3320The33zaThe3328The33源The33zaThe3328Theproducerprodu匚如producerproducerproduce「producerproducerproducerproducerproducerproducerproducerproducerproducerproducerproducer?土0Ukun@>lflcun-Lcnovo-ldeaPad-Y471A:?/laMlikunSlikun-Lenovo-ldedPdd-Y471A:~$cdlab4ttkungltkun-Lenovo-ldeaPdd-Y471A：~/lab4$./consjmer1331BTheconsumerhaspaper*TheconsuriErgets3319TheconsumerTheconsumergets3318TheconsumerTheconsumergets3318TheconsumerTheconsumergets331STheconsumerTheconsumergets3318TheconsumerTheconsumergets3318Theconsumer?土0Ukun@>lflcun-Lcnovo-ldeaPad-Y471A:?/laMlikunSlikun-Lenovo-ldedPdd-Y471A:~$cdlab4ttkungltkun-Lenovo-ldeaPdd-Y471A：~/lab4$./consjmer1331BTheconsumerhaspaper*tobaccoandgluehaspaper-tobaccoandgluehaspaper-tobaccoendgluehaspaper.tobaccoandgluehaspaper-tobaccoandgluehaspaper-tobaccoandgluehaspaper.tobaccoandgluehaspaper-tobaccoandgluehaspaper.tobaccoandgluehaspaper.tobaccoandglue?*Ukun@>Hlcun-Lenovo-IdeaPad-Y471A:?/laMlikunOlikun-Lenovo-ldedPad-Y471A:~Scdlab4ttkungltkun-Lenovo-ldeaPdd-Y471A：~/lab45./consumer23319Theconsumerhastobacco.Theconsumergetsglueandpaper3319Theconsumerhastobacco.Theconsumergetsglueandpaper3319TheconsumerhastobaccotTheconsumergetsgtueandpaper3319Theconsumerhastobacco.Theconsumergetsglueandpaper3319Theconsumerhastobacco.Theconsumergetsglueandpaper3319Theconsumerhastobacco.Theconsumergetsglueandpaper3319TheconsumerhastobaccofTheconsumergetsglueandpaper3319TheconsumerhastotiaccoLTheconsumergetsglueandpaper3319Theconsumerhastobacco.Theconsumergetsglueandpaper2S19Theconsumerhastobacco.Theconsumergetsglueandpaper3319Theconsumerhastobacco.TheconsumergetsgLueandpaper分析：多進程的系統(tǒng)中避免不了進程間的相互關(guān)系。進程互斥是進程之間發(fā)生的一種間接性作用，一般是程序不希望的。通常的情況是兩個或兩個以上的進程需要同時訪問某個共享變量。我們一般將發(fā)生能夠問共享變量的程序段稱為臨界區(qū)。兩個進程不能同時進入臨界區(qū)，否則就會導(dǎo)致數(shù)據(jù)的不一致，產(chǎn)生與時間有關(guān)的錯誤。解決互斥問題應(yīng)該滿足互斥和公平兩個原則，即任意時刻只能允許一個進程處于同一共享變量的臨界區(qū)，而且不能讓任一進程無限期地等待。進程同步是進程之間直接的相互作用，是合作進程間有意識的行為，典型的例子是公共汽車上司機與售票員的合作。只有當售票員關(guān)門之后司機才能啟動車輛，只有司機停車之后售票員才能開車門。司機和售票員的行動需要一定的協(xié)調(diào)。同樣地，兩個進程之間有時也有這樣的依賴關(guān)系，因此我們也要有一定的同步機制保證它們的執(zhí)行次序。信號量機制就是其中的一種。信號燈機制即利用pv操作來對信號量進行處理。PV操作由P操作原語和V操作原語組成（原語是不可中斷的過程），對信號量進行操作，具體定義如下：P（S）：①將信號量S的值減1，即S=S-