Linux与Windows的设备驱动差异比较.ppt

AComparativeStudyoftheLinuxandWindowsDeviceDriverArchitectureswithafocusonIEEE1394 highspeedserialbus drivers MelekamTsegayeg98t4414 campus ru ac za SupervisorsProf RichardFoss BradleyKlinkradt Overview TheLinuxandWindowsdriverarchitecturesTheLinuxandWindowsIEEE1394driverstacksDriverdevelopmentonthetwoplatformsResultsofthestudy Whythestudywasconducted MicrosoftWindowsandLinuxTwoofthemostpopularoperatingsystemsNopreviouscomparisonsoftheirdriverarchitecturesdonebyotherresearchersIEEE1394 firewire PopularbusofferinghighdatatransferratesActiveresearchareafortheCSdepartment sAudioEngineeringGroup IEEE1394 DataTransferratesof100 200and400MbpsIsochronousmodeoftransferGuaranteedbandwidth 80 AsynchronousmodeoftransferGuaranteedpacketdelivery 20 ormore Fullyplug nplay IEEE1394ConsumerProducts DeviceDrivers Adriverisapieceofsoftwarethatextendsakernel sfunctionalityDriversenableapplications throughthekernel totransferdatatoandfromadevicetocontroltheadevicetoallowmodificationofitsattributesComposedofasetofroutinesthatakernelcallsatappropriatetimese g read write Typicaldriverroutines AdriverwouldimplementInitialisationCleanupOpenReadWriteI OControl ioctl Close TheWindowsdriverarchitecture StandardmodelTheWindowsDriverModel WDM bus functional filterdriversPnP PowermanagementCommunicationI Orequestpackets IRPs TheLinuxdriverarchitecture NostandarddrivermodelDriversaremodulesNoPnP PowermanagementmessagedispatchingCommunicationthroughdirectfunctioncalls Sidebysidecomparisonofthetwodriverarchitectures Linux Windows IEEE1394driverstacks TheWindowsIEEE1394stackclosedsourcemaintainedbyMicrosoftstableTheLinuxIEEE1394stackopensourcemaintainedbytheLinux1394community privateindividuals taggedexperimental TheWindowsIEEE1394stack HostcontrollerBusdriverClientdriversCommunicationI Orequestblock IRB TheLinuxIEEE1394stack HostcontrollerBusdriversClientdriversCommunicationdirectfunctioncallsDirectdriverpossible SidebysidecomparisonofthetwoIEEE1394stacks Linux Windows TheWindowsIEEE1394implementation TheLinuxIEEE1394implementation WhatoperationsshouldIEEE1394clientdriversprovide AsynchronousOperationsReadWriteLockListenRegisterAsynchronousListeningDeregisterAsynchronousListeningIsochronousoperationsListenTalkAsynchronousstreaming WhatoperationsshouldIEEE1394clientdriversprovide Continued BusresethandlingRegisterBusResetHandlerGenerateSoftBusResetObtainBusInformation e g nodecount LocalconfigurationROMmanipulationNetworktroubleshootingPingingofnodes DeviceDriverDevelopmentEnvironments Issuestobeconsideredwhencreatingdrivers MemorymanagementThekernelprovidesmemoryallocation de allocationroutinesHastwopoolsofmemory swappable non swappable DatastructuresThekernelprovidesimplementationsforqueues lists stacksSynchronisationwithspinlocks mutexes semaphores signalobjects Issuestobeconsideredwhencreatingdrivers Continued Driversroutinesmustbere entranti e shouldbeexecutablebymultiplethreadswithnoproblemsavoidrecursionHardwareAbstractionLayeruseHALroutinesprovidedbythekerneltoaccesshardware Mapofsoftwareproducedduringthisstudy Windowsraw1394driver Linuxraw1394 2driver LinuxIeee1394diag DriverTests TestswereruntodeterminehighestdatatransferratesthatcanbeachievedbyeachoftheIEEE1394drivershowclosethesecametothetheoreticalmaximumof50MB sBusanalyserusedtomeasurethedurationofdatatransferstheamountofdatatransferredCalculatedthedatatransferrateinMB s Testresults IsochronousmodeWindowsraw13948 9MB spacketsize1024bytesLinuxraw13944 5MB spacketsize512bytesIsochronousmode buffered Linuxraw1394 28 9MB spacketsize1024bytesWindowsraw139417 7MB spacketsize2048bytes Testresults continued DriversfrombothLinuxandWindowsdonottransferdataatarateclosetothetheoretical50MB sTheyachievealmosthalfthatduetothePCIbusbottleneck theoretical132MB s InpracticehavethatavailablesharedbyallI OdevicesattachedtothePCIbusThePCIbushaslatencyproblemsdriverimplementationmaynotbeefficient Conclusion AcomparisonoftheWindowsandLinuxdriverarchitectureshasshownthatDriversforthetwoplatformhavesimilarcomponentscomposedofroutinesforperformingI OanddevicecontroldriversaremoduleswhichareloadableatruntimeWindowshasaformallydefineddrivermodel Linuxdoesnot PnPandpowermanagementsupportintegratedintheWindowsarchitecture notsoinLinux Conclusion continued AcomparisonoftheWindowsandLinuxIEEE1394stackshasshownthatTheirIEEE1394driverstacksarebrokenupintosimilarlayershostcontroller busandclientdriverlayersEachstackprovidesthestandardIEEE1394operations bothasynchronousandisochronous TheLinuxIEEE1394stackisopensourcewhiletheWindowsstackisproprietaryEasiertocreateIEEE1394driversforLinuxthanWindowssinceallsourcecodeisavailable Futurework IEEE1394 1bridgeawarenessIEEE1394 1allowsextendingtheno ofnodesto64Kinsteadofthecurrent63stillindraftphaseTheWindowsandLinuxIEEE1394driverdevelopersdidnottakeintoaccountIEEE1394 1bridgingintheirdesignT