計算機科學與技術學院實驗報告實驗題目：ExtensionofAddrSpace學號：日期：202371-25班級：2023-3姓名：陶旭濤EmaiI：實驗目的：在了解了Nachos裝入并執(zhí)行單個用戶進程的情況后，我們就需要進一步完畢用戶內存空間的擴充以便多用戶程序同時駐留內存，進而使多用戶進程并發(fā)執(zhí)行。硬件環(huán)境：Mem：3.9GCPU：Intel?Coretm2QuadCPUQ9500@2.83GHzx4Disk：15.5GB軟件環(huán)境：System：ubuntu12.O4LSTi386gcc:(Ubuntu4.6.3—1ubuntu5)4.6.3nachossystem實驗環(huán)節(jié)：要在Nachos中實現(xiàn)多用戶程序同時駐留內存并發(fā)執(zhí)行,一方面涉及到Nachos的兩個系統(tǒng)調用：Exec()和Exit()o這兩個系統(tǒng)調用也是構造父子進程并發(fā)執(zhí)行的基礎。假設我們有以卜兩個用戶程序:../test/exec.c和../test/ha11.c../test/ha1t.c第65頁用戶進程管理設計#incIude"syscaII.h"intmain()(HaltO}../test/exec.c#incIude"syscaII.h"intmain0(Spacidpid;pid=Exec("../test/haIt.noff");HaIt0)在文獻../test/exec,c第5行上的語句Exec是一條Nachos的系統(tǒng)功能調用，它的功能為裝入并執(zhí)行以其參數(shù)為名的可執(zhí)行文獻，即創(chuàng)建一個新的用戶進程。假設我們先執(zhí)行../test/exec.noff程序,則../test/exec.noff會在它還沒有執(zhí)行結束時又裝入并執(zhí)行此外一個程序halt,n。開，并與它同時駐留內存.DEBUG(,dd\n,numPages,size);trst,setupthetranslationpageTable=newTranslationEntry[numPages];for(t=;t<numPages;t++){pageTable[t].vtrtualPage=t;pageTable[i].physicalPage=usermap->Find();pageTable[t].valid=TRUE;pageTable[t].use=FALSE;pageTable[i].dirty=FALSE;pageTable[t].readonly=FALSE;//aseparatepage,wecouldsetits//pagestoberead-onlypageTable[i].physicaIPage=usermap―>Find();避免從頭開始物理存儲覆蓋了前一個用戶程序的內存內容運用Nachos在../userprog/bitmap.h中文獻定義的Bitmap類。運用bitmap記錄和申請內存物理幀，使不同的程序裝入到不同的物理空間中去，下面是對新的內存分派存儲算法，改善了對多個用戶程序的同時進駐內存的支持if(noffH.code.size>){DEBUG(,'>.W\n,noffH.code.vtrtualAddr,noffH.code.size);intnunberofPages;nunberofPdgesMltvRoundUp(noffH.code.size,Pagesize);for(i=;t<nunberofPages;t**){prtntf(,pageTable[t].phystcalPage,PageStze);print",noffH.code.InFUeAddr+VPageStze);print”.PageStze);executable->ReadAt(?(Mchtne->natnMe?)ry[pdgeTable[t].phy$kalPage*PageStze]),PdgeSUe,noffH.code.tnFt.leAd<Jr*t*Pagestze);})if(noffH.tnttData.size>){DEBUG(,,noffH.tnttData.vtrtualAddr,noffH.tnttData.size);executable->fleadAt(4(Mchtne->nainHe?)ry[fK>ffH.tnttData.vtrtuaUddr]),noffH.initData.size,rx>ffH.tnttOata.tnFUeAddr);intnunberofP.firstP;nunberofP=dtvRoundup(noffH.tnttData.size,PageSlze);(Wr,PageStze);for(t?firstP;t<nuHl)erofP;t++){prtntf(,pageTable[t].phystcalPage,PageSlze);prtntf(,i)offH.tnttData.InFUeAddr+VPageSize);printf();executable->ReadAt(t(Aachtne->NtnNeRory[pageTable(t].phystcdlPage*PageStze]),PageStze,noffH.tnttData.tnFUeAddr+t*PageStze);))Print();)這是對Bi(Map的代碼修改，每次分派的時候要找到bitmap中的空閑頁進行分派，而不能從0頁開始分派在AddressSpace類中聲明bi(map對象staticBitMap*mbitmap=newBitMap(NumPhysPages);voidBitMap::Prtnt()(printf(\n);for(inti=;i<numBits;t++)if(Test(t))prtntf(,t)；prtntf();)//Thesearen'tneededuntiltheFILESYSassignment////BitMap::FetchFromFile//InitializethecontentsofabitmapfromaNachosfile.////"file"istheplacetoreadthebitmapfrom//voidBitMap::FetchFrom(OpenFtle*file)(file->ReadAt((char*)map,numWords*sizeof(unsigned),);)////BitMap::WrtteBack//StorethecontentsofabitmaptoaNachosfile.////"file"istheplacetowritethebitmapto//voidBttMap::WriteBack(OpenFtle*file)Ifile->WrtteAt((char*)map,numWords*sizeof(unsigned),);運營./nachos-x../test/exec.noffking@kingvm:~/nachos-3.4/code/lab7-8$./nachos-x../test/exec.noff★★★king@kingvm:~/nachos-3.4/code/lab7-8$./nachos-x../test/exec.noff★★★thread0looped0times***thread1looped0times★★★thread0looped1times★★★thread1looped1times★★★thread0looped2times★★★thread1looped2times***thread0looped3times★★★thread1looped3times★★★thread1looped4times★★★thread0looped4timestheallocatedphysicalAddress:?theaddressintheexecutablefile:40copysize128theallocatedphysicalAddress:128theaddresstntheexecutablefile:168copysize128theallocatedphysicalAddress:256theaddressintheexecutablefile:296copysize128pagetabledump:12pagestntotalVtrPage,PhysPagee,01,12,23,34,45,56,67,78,89,910,1011,11Exec—調用theallocatedphysicalAddress:1536theaddressintheexecutablefile:40copysize128theallocatedphysicalAddress:1664theaddressintheexecutablefile:168copysize128pagetabledump:10pagesintotalVirPage,PhysPage0,121,132,143,154,165,176,187,198,209,21Machinehalting!Ticks:total165,idle0,system140,user25DiskI/O:reads0,writes0ConsoleI/O:reads0,writes0Paging:faults0NetworkI/O:packetsreceived0,sent0Cleaningup...ktng