• Navigation überspringen
  • Zur Navigation
  • Zum Seitenende
Organisationsmenü öffnen Organisationsmenü schließen
Friedrich-Alexander-Universität Lehrstuhl für Informatik 4 (Systemsoftware)
  • FAUZur zentralen FAU Website
  1. Friedrich-Alexander-Universität
  2. Technische Fakultät
  3. Department Informatik
Suche öffnen
  • English
  • Campo
  • StudOn
  • FAUdir
  • Stellenangebote
  • Lageplan
  • Hilfe im Notfall
  1. Friedrich-Alexander-Universität
  2. Technische Fakultät
  3. Department Informatik
Friedrich-Alexander-Universität Lehrstuhl für Informatik 4 (Systemsoftware)
Menu Menu schließen
  • Lehrstuhl
    • Team
    • Aktuelles
    • Kontakt und Anfahrt
    • Leitbild
    • 50-jähriges Jubiläum
    Portal Lehrstuhl
  • Forschung
    • Forschungsbereiche
      • Betriebssysteme
      • Confidential Computing
      • Embedded Systems Software
      • Verteilte Systeme
    • Projekte
      • AIMBOS
      • BALu
      • BFT2Chain
      • DOSS
      • Mirador
      • NEON
      • PAVE
      • ResPECT
      • Watwa
    • Projektkampagnen
      • maRE
    • Seminar
      • Systemsoftware
    Portal Forschung
  • Publikationen
  • Lehre
    • Sommersemester 2025
      • Applied Software Architecture
      • Ausgewählte Kapitel der Systemsoftware
      • Betriebssystemtechnik
      • Projekt angewandte Systemsoftwaretechnik
      • System-Level Programming
      • Systemnahe Programmierung in C
      • Systemprogrammierung 1
      • Verteilte Systeme
    • Wintersemester 2025/26
      • Systemprogrammierung 2
      • Betriebssysteme
      • Middleware – Cloud Computing
      • Echtzeitsysteme
      • Virtuelle Maschinen
      • Web-basierte Systeme
      • Projekt angewandte Systemsoftwaretechnik
      • Aktuelle Entwicklung in Verteilten und Objektorientierten Betriebssystemen (für Bachelor-/Masterarbeit)
    Portal Lehre
  • Examensarbeiten
  1. Startseite
  2. Extern

Extern

Bereichsnavigation: Lehre
  • Betriebssysteme
    • Vorlesung
      • Folien
    • Übung
      • Seminar
      • Aufgaben
      • Aufgabe 0: C++ Streams
        • Aufgabe 1: Ein-/Ausgabe
          • Aufgabe 2: Unterbrechungen
            • Aufgabe 3: Pro-/Epilog
              • Aufgabe 4: Kontextwechsel
                • Aufgabe 5: Zeitscheiben
                  • Assembler Crashkurs
                    • C++ Crashkurs
                      • Entwicklungsumgebung
                        • FAQ
                          • Ruhmeshalle

                        Aufgabe 2: Unterbrechungen

                        Namespaces | Classes | Enumerations | Functions | Constants
                        Core Namespace Reference

                        Implements an abstraction for CPU internals. More...

                        Namespaces

                        namespace  Interrupt
                         Exception and Interrupt control.
                         

                        Classes

                        class  CR
                         Access to the Control Register. More...
                         
                        class  MSR
                         Access to the Model-Specific Register (MSR) More...
                         

                        Enumerations

                        enum  CR0 : uintptr_t {
                          CR0_PE = 1U << 0 ,
                          CR0_MP = 1U << 1 ,
                          CR0_EM = 1U << 2 ,
                          CR0_TS = 1U << 3 ,
                          CR0_ET = 1U << 4 ,
                          CR0_NE = 1U << 5 ,
                          CR0_WP = 1U << 16 ,
                          CR0_AM = 1U << 18 ,
                          CR0_NW = 1U << 29 ,
                          CR0_CD = 1U << 30 ,
                          CR0_PG = 1U << 31
                        }
                         Control Register 0. More...
                         
                        enum  CR4 : uintptr_t {
                          CR4_VME = 1U << 0 ,
                          CR4_PVI = 1U << 1 ,
                          CR4_TSD = 1U << 2 ,
                          CR4_DE = 1U << 3 ,
                          CR4_PSE = 1U << 4 ,
                          CR4_PAE = 1U << 5 ,
                          CR4_MCE = 1U << 6 ,
                          CR4_PGE = 1U << 7 ,
                          CR4_PCE = 1U << 8 ,
                          CR4_OSFXSR = 1U << 9 ,
                          CR4_OSXMMEXCPT = 1U << 10 ,
                          CR4_UMIP = 1U << 11 ,
                          CR4_VMXE = 1U << 13 ,
                          CR4_SMXE = 1U << 14 ,
                          CR4_FSGSBASE = 1U << 16 ,
                          CR4_PCIDE = 1U << 17 ,
                          CR4_OSXSAVE = 1U << 18 ,
                          CR4_SMEP = 1U << 20 ,
                          CR4_SMAP = 1U << 21 ,
                          CR4_PKE = 1U << 22
                        }
                         Control Register 4. More...
                         
                        enum  MSRs : uint32_t {
                          MSR_PLATFORM_INFO = 0xceU ,
                          MSR_TSC_DEADLINE = 0x6e0U ,
                          MSR_EFER = 0xC0000080U ,
                          MSR_STAR = 0xC0000081U ,
                          MSR_LSTAR = 0xC0000082U ,
                          MSR_SFMASK = 0xC0000084U ,
                          MSR_FS_BASE = 0xC0000100U ,
                          MSR_GS_BASE = 0xC0000101U ,
                          MSR_SHADOW_GS_BASE = 0xC0000102U
                        }
                         Model-Specific Register Identifiers. More...
                         
                        enum  MSR_EFER : uintptr_t {
                          MSR_EFER_SCE = 1U << 0 ,
                          MSR_EFER_LME = 1U << 8 ,
                          MSR_EFER_LMA = 1U << 10 ,
                          MSR_EFER_NXE = 1U << 11 ,
                          MSR_EFER_SVME = 1U << 12 ,
                          MSR_EFER_LMSLE = 1U << 13 ,
                          MSR_EFER_FFXSR = 1U << 14 ,
                          MSR_EFER_TCE = 1U << 15
                        }
                         

                        Functions

                        void init ()
                         Initialize this CPU core. More...
                         
                        void exit ()
                         Deinitialize this CPU core. More...
                         
                        unsigned getID ()
                         Get the ID of the current CPU core using LAPIC::getID() with an internal lookup table. More...
                         
                        unsigned count ()
                         Get number of available CPU cores. More...
                         
                        unsigned countOnline ()
                         Get number of successfully started (and currently active) CPU cores. More...
                         
                        bool isOnline (uint8_t core_id)
                         Check if CPU core is currently active. More...
                         
                        void pause ()
                         Gives the core a hint that it is executing a spinloop and should sleep "shortly". More...
                         
                        void idle ()
                         Halt the CPU core until the next interrupt. More...
                         
                        void die ()
                         Permanently halts the core. More...
                         

                        Constants

                        const unsigned MAX = 8
                         Maximum number of supported CPUs.
                         

                        Detailed Description

                        Implements an abstraction for CPU internals.

                        These internals include functions to allow or deny interrupts, access control registers.

                        Enumeration Type Documentation

                        enum Core::CR0 : uintptr_t

                        Control Register 0.

                        See also
                        ISDMv3, 2.5 Control Registers
                        Enumerator
                        CR0_PE 

                        Protected Mode enabled.

                        CR0_MP 

                        Monitor co-processor.

                        CR0_EM 

                        Emulation (no x87 floating-point unit present)

                        CR0_TS 

                        Task switched.

                        CR0_ET 

                        Extension type.

                        CR0_NE 

                        Numeric error.

                        CR0_WP 

                        Write protect.

                        CR0_AM 

                        Alignment mask.

                        CR0_NW 

                        Not-write through caching.

                        CR0_CD 

                        Cache disable.

                        CR0_PG 

                        Paging.

                        enum Core::CR4 : uintptr_t

                        Control Register 4.

                        See also
                        ISDMv3, 2.5 Control Registers
                        Enumerator
                        CR4_VME 

                        Virtual 8086 Mode Extensions.

                        CR4_PVI 

                        Protected-mode Virtual Interrupts.

                        CR4_TSD 

                        Time Stamp Disable.

                        CR4_DE 

                        Debugging Extensions.

                        CR4_PSE 

                        Page Size Extension.

                        CR4_PAE 

                        Physical Address Extension.

                        CR4_MCE 

                        Machine Check Exception.

                        CR4_PGE 

                        Page Global Enabled.

                        CR4_PCE 

                        Performance-Monitoring Counter enable.

                        CR4_OSFXSR 

                        Operating system support for FXSAVE and FXRSTOR instructions.

                        CR4_OSXMMEXCPT 

                        Operating System Support for Unmasked SIMD Floating-Point Exceptions.

                        CR4_UMIP 

                        User-Mode Instruction Prevention.

                        CR4_VMXE 

                        Virtual Machine Extensions Enable.

                        CR4_SMXE 

                        Safer Mode Extensions Enable.

                        CR4_FSGSBASE 

                        Enables the instructions RDFSBASE, RDGSBASE, WRFSBASE, and WRGSBASE.

                        CR4_PCIDE 

                        PCID Enable.

                        CR4_OSXSAVE 

                        XSAVE and Processor Extended States Enable.

                        CR4_SMEP 

                        Supervisor Mode Execution Protection Enable.

                        CR4_SMAP 

                        Supervisor Mode Access Prevention Enable.

                        CR4_PKE 

                        Protection Key Enable.

                        enum Core::MSRs : uint32_t

                        Model-Specific Register Identifiers.

                        Selection of useful identifiers.

                        See also
                        ISDMv4
                        Enumerator
                        MSR_PLATFORM_INFO 

                        Platform information including bus frequency (Intel)

                        MSR_TSC_DEADLINE 

                        Register for LAPIC::Timer Deadline mode.

                        MSR_EFER 

                        Extended Feature Enable Register,.

                        See also
                        Core::MSR_EFER
                        MSR_STAR 

                        eip (protected mode), ring 0 and 3 segment bases

                        MSR_LSTAR 

                        rip (long mode)

                        MSR_SFMASK 

                        lower 32 bit: flag mask, if bit is set corresponding rflag is cleared through syscall

                        MSR_GS_BASE 

                        Current GS base pointer.

                        MSR_SHADOW_GS_BASE 

                        Usually called MSR_KERNEL_GS_BASE but this is misleading.

                        enum Core::MSR_EFER : uintptr_t
                        Enumerator
                        MSR_EFER_SCE 

                        System Call Extensions.

                        MSR_EFER_LME 

                        Long mode enable.

                        MSR_EFER_LMA 

                        Long mode active.

                        MSR_EFER_NXE 

                        No-Execute Enable.

                        MSR_EFER_SVME 

                        Secure Virtual Machine Enable.

                        MSR_EFER_LMSLE 

                        Long Mode Segment Limit Enable.

                        MSR_EFER_FFXSR 

                        Fast FXSAVE/FXRSTOR instruction.

                        MSR_EFER_TCE 

                        Translation Cache Extension.

                        Function Documentation

                        void Core::init ( )

                        Initialize this CPU core.

                        Mark this core as online and setup the cores LAPIC by assigning it a unique logical APIC ID

                        Note
                        Should only be called from kernel_init() during startup.
                        void Core::exit ( )

                        Deinitialize this CPU core.

                        Mark this Core as offline

                        Note
                        Should only be called from kernel_init() after returning from main() or main_ap().
                        unsigned Core::getID ( )

                        Get the ID of the current CPU core using LAPIC::getID() with an internal lookup table.

                        Returns
                        ID of current Core (a number between 0 and Core::MAX)
                        unsigned Core::count ( )

                        Get number of available CPU cores.

                        Returns
                        total number of cores
                        unsigned Core::countOnline ( )

                        Get number of successfully started (and currently active) CPU cores.

                        Returns
                        total number of online cores
                        bool Core::isOnline ( uint8_t  core_id)

                        Check if CPU core is currently active.

                        Parameters
                        core_idID of the CPU core
                        Returns
                        true if successfully started and is currently active
                        void Core::pause ( )
                        inline

                        Gives the core a hint that it is executing a spinloop and should sleep "shortly".

                        Improves the over-all performance when executing a spinloop by waiting a short moment reduce the load on the memory.

                        See also
                        ISDMv2, Chapter 4. PAUSE - Spin Loop Hint
                        void Core::idle ( )
                        inline

                        Halt the CPU core until the next interrupt.

                        Halts the current CPU core such that it will wake up on the next interrupt. Internally, this function first enables the interrupts via sti and then halts the core using hlt. Halted cores can only be woken by interrupts. The effect of sti is delayed by one instruction, making the sequence sti hlt atomic (if interrupts were disabled previously).

                        See also
                        ISDMv2, Chapter 4. STI - Set Interrupt Flag
                        ISDMv2, Chapter 3. HLT - Halt
                        void Core::die ( )
                        inline

                        Permanently halts the core.

                        Permanently halts the current CPU core. Internally, this function first disables the interrupts via cli and then halts the CPU core using hlt. As halted CPU cores can only be woken by interrupts, it is guaranteed that this core will be halted until the next reboot. The execution of die never returns. On multicore systems, only the executing CPU core will be halted permanently, other cores will continue execution.

                        See also
                        ISDMv2, Chapter 3. CLI - Clear Interrupt Flag
                        ISDMv2, Chapter 3. HLT - Halt
                        Friedrich-Alexander-Universität
                        Erlangen-Nürnberg

                        Schlossplatz 4
                        91054 Erlangen
                        • Impressum
                        • Datenschutz
                        • Barrierefreiheit
                        • Facebook
                        • RSS Feed
                        • Xing
                        Nach oben