ULinus Benedict Torvalds yinjineli yesoftware yaseFinnish yaseMelika, eyaziwa ngokuqala nokugcina uphuhliso lweLinux kernel,
Kwiintsuku ezithile ezidlulileyo ULinus Torvalds wenza uluvo lwakhe malunga nokuphelisa inkxaso kuyilo lweprosesa i486 kwi Linux kernel. Ulwakhiwo oludala lwaxoxwa kwiintsuku ezimbalwa ezidlulileyo kumsonto ojonge ukuba i-kernel inokusingatha njani ngcono izintlu zokusetyenziswa kwamva nje (LRU), indlela yokugcina umkhondo wamaphepha ememori.
Ngexesha UTorvalds waphanda ikhowudi yamaqabane, kubonakala ngathi kuphoxekile kukufuna ukubandakanya izicombululo yanele kwii-CPU ezindala. Ke ngoko, ucebise ukuphelisa inkxaso yekhithi endala, enokuba yindlela elula yokulungisa imiba yenkumbulo.
“Sahlukana nenkxaso ye-i386 ngo-2012. Mhlawumbi lixesha lokuba silahle inkxaso ye-i486 ngo-2022? ULinus Torvalds uthi
Senze (ngokuqinisekileyo ayilunganga: hayi i-SMP-ekhuselekileyo, okt iya kusebenza kakuhle naxa ijongene nokufikelela ngaxeshanye ukusuka kwimisonto emininzi yokubulawa, kodwa oomatshini be-SMP Class 486 abazange baxhaswe nangona babekho ngokobuchwepheshe)
Kufuneka kukhunjulwe ukuba i486 CPU series yakhululwa ngo-1989 kwaye okwangoku zimbalwa kakhulu izinikezelo zeLinux ezinje ngeGentoo, Slackware kunye neKNOPPIX ziyaqhubeka nokuxhasa olu lwakhiwo.
Ngokutsho kweTorvalds, iingxaki ezibangelwa kukuxhasa izakhiwo eziphelelwe lixesha ezisetyenziswa ngabantu abambalwa kunokuba lula ukusombulula ngokususa inkxaso yabo. Ulawulo lwememori ye-LRU yeeprosesa ezindala nazo ziya kuba yimeko enjalo.
Ngokunyaniseka, andizukukhathalela ukunyusa eyona mfuno isezantsi ubuncinci i-M586TSC, ndishiya ngasemva ezinye zee-clones "zePentium" zangaphambili. Kuba 'rdtsc' yeyona ngxaki imbi ngakumbi kune-CMPXCHG8B.
Kwaye oko yonke ibila ukuya kutsho ku-cmpxchg8b, umyalelo othelekisa kwaye emva koko utshintshe iibyte ezisibhozo (okanye i-64 bits) yolwazi kwimemori yekhompyutha. Ilungu loluhlu lokuposa uPeter Zijlstra ucebise ukuba iLinux kufuneka ixhase kuphela iiprosesa ezikwaziyo ukwenza oku, ishiya i-486-bit i32 ngasemva kwaye ithetha ukuba ii-Linux kernels ezintsha ziya kuqhuba kwi-hardware yeklasi ye-P5 okanye entsha.
Umyalelo we cmpxchg8b ngunobangela wempazamo ye-'F00F' ukusuka kwiPentium yasekuqaleni, apho i-CPU echaphazelekayo ngaphandle kokunciphisa inkqubo yokusebenza iyeka ukusebenza de iphinde iqaliswe xa icelwa ukuba iphumeze umyalelo.
Ngokwenyani, andiqondi kwaphela ukuba kutheni iinkozo zangoku zisebenza kwi-i486, kuba ijongeka ngathi phuma_ku_umsebenzisi_imode_prepare -> arch_exit_to_user_mode_prepare, kwaye iphelela ekubeni nengxelo engenamiqathango 'rdtsc'.
Ndicinga ukuba awukhange uyenze ukuba isebenze.RANDOMIZE_KSTACK_OFFSET*? Ngamanye amazwi, imidiya yethu engeyiyo eyePentium IYASEBENZA IYAPHUMELA KWAYE YAPHUKELWE ngoku.
Ngokutsho kwakhe, Kuyathandabuzeka kakhulu ukuba i-i486 hardware isasebenza. Alithandabuzeki elokuba basekho abantu abazimisele ngolo hlobo ehlabathini, abakholelwa ukuba iingxaki ezibangelwayo zinokunqotshwa ngokulula, kodwa ukusuka kwindawo yokujonga i-kernel, esi sikhundla asifanelekanga ngokwenene.
Ke andicingi ukuba i-i486-class hardware iyasebenza. Ewe, ndiqinisekile ukuba zikhona (uMaciej ngumzekelo), kodwa kwimbono yophuhliso lwe-kernel, andicingi ukuba zifanelekile ngokwenene. Ngexesha elithile, abantu banazo njengeziqwenga zemyuziyam. Bangakwazi nokulawula iinuclei zeemyuziyam.
Kufuneka kuthiwe i-architecture I486 yaqala ngo-1989 kwaye yatshintshwa yi-Intel's Pentium ngo-1993. I-Intel yalahla i-i486 ngo-2007 kwaye namhlanje isiseko sedatha yedatha yemveliso yeArk ayinakukhankanywa ngentsapho yeprosesa.
Abo basasebenzisa izixhobo kwakudala baziyeke ukwenza oko ngaphandle kwenkxaso, ngaphandle kokufumana ikiti entsha okanye abaphuhlisi besoftware bacinga ngeqonga.
Ukufumana iinkcukacha ezingaphezulu, i-Intel 80486 (i486, 486) i-microprocessor yentsapho ye-x86, eyenziwa yi-Intel. Ikhutshwe kwi-1989. Ngokubhekiselele kwiprosesa ye-architecture, i-80486 ifana kakhulu neyandulelayo, i-Intel 80386, kunye nokongezwa kwemiyalelo embalwa eyongezelelweyo. Ngoko ke, luyilo lweCISC.
Ukusuka kwindawo yokujonga i-microarchitectural point, kwakukho uphuculo olukhulu ngelo xesha: umyalelo odibeneyo odibeneyo kunye ne-cache yedatha, iYunithi yokuLungiselela iNdawo eFloating (FPU), kunye ne-interface yebhasi ephuculweyo.
Ekugqibeleni ukhankanya i abasebenzisi abanezixokelelwano ezineprosesa ze-i486 baya kuba nakho ukusebenzisa iinguqulelo zeLTS zekerneleya kuhlala iminyaka emininzi ezayo.
Inkxaso yeemodeli ezindala zeprosesa kunye nezixhobo zinokususwa kwi-Linux kernel ngenxa yezizathu ezahlukeneyo, ezifana nokwenza lula kunye nokuphucula ikhowudi, ukunciphisa ubunzima be-kernel kunye nokugcinwa, okanye ukugxila kwizixhobo zangoku kunye nezidumileyo. Eminye imizekelo yeemodeli zakudala ezinokususwa kwi-Linux kernel inkxaso ibandakanya:
Iiprosesa ezindala: ezifana ne-Intel i386, i486, okanye ezinye iiprosesa ze-AMD ezindala. Ezi processors zindala kakhulu kwaye azixhasi iimpawu zamva nje zeLinux kernel.
Izixhobo ezidala zeperipheral: Ezinje ngeteyiphu drives, ifloppy drives, okanye izandi ezindala okanye amakhadi evidiyo. Ezi zixhobo aziqhelekanga namhlanje, kwaye ke inkxaso yazo inokurhoxiswa ukunciphisa ubunzima be-kernel.
Ubuchwephesha obuphelelwe lixesha: njengenkxaso yeprotocol yenethiwekhi ye-IPX, eyayiqhele ukusetyenziswa kuthungelwano lwekhompyutha kumashumi eminyaka eyadlulayo. Njengoko iteknoloji iqhubela phambili kwaye itshintsha, inkxaso yetekhnoloji eyehliweyo inokurhoxiswa kwi-kernel.