CPU Management

CPU. More...

Collaboration diagram for CPU Management:

Detailed Description

CPU.

Modules
	CLI
	Clear Interrupt Flag (CLI) Handling.
	GDT
	Global Descriptor Table.
	IDT
	Interrupt Descriptor Table.
	Interrupts
	Interrupt Handling.
	IPI
	Inter-Processor Interrupts (IPIs)
	IRQ
	Interrupt Requests (IRQs)
	Per-CPU Data
	Per CPU data.
	Port I/O
	I/O port operations and reservations.
	SIMD
	SIMD context management.
	Stack Pointer
	Helpers for managing stacks.
	Syscall
	System Call Interface.
	TSS
	Task State Segment.

Data Structures
struct	cpu_t
	CPU structure. More...

Macros
#define	CPU_OFFSET_SELF   0x0
	The offset of the self member in the cpu_t structure.
#define	CPU_OFFSET_SYSCALL_RSP   0x10
	The offset of the syscall_ctx_t pointer in the cpu_t structure.
#define	CPU_OFFSET_USER_RSP   0x18
	The offset of the userRsp member in the cpu_t structure.
#define	CPU_OFFSET_ID   0x8
	The offset of the id member in the cpu_t structure.
#define	CPU_MAX   UINT8_MAX
	Maximum number of CPUs supported.
#define	CPU_ID_BOOTSTRAP   0
	ID of the bootstrap CPU.
#define	CPU_ID_INVALID   UINT16_MAX
	Invalid CPU ID.
#define	CPU_STACK_CANARY   0x1234567890ABCDEFULL
	CPU stack canary value.
#define	CPU_FOR_EACH(cpu)
	Macro to iterate over all CPUs.

Typedefs
typedef uint16_t	cpu_id_t
	Type used to identify a CPU.

Functions
void	cpu_init (cpu_t *cpu)
	Initializes a CPU structure.
void	cpu_stacks_overflow_check (void)
	Checks the current CPU for stack overflows.
uint64_t	cpu_halt_others (void)
	Halts all other CPUs.
uintptr_t	cpu_interrupt_stack_top (void)
	Gets the top of the interrupt stack for the current CPU.
static uint16_t	cpu_amount (void)
	Gets the number of identified CPUs.
static cpu_t *	cpu_get_by_id (cpu_id_t id)
	Gets a CPU structure by its ID.
static cpu_t *	cpu_get_next (cpu_t *current)
	Gets the next CPU in the CPU array.

Variables
cpu_t *	_cpus [CPU_MAX]
	Array of pointers to cpu_t structures for each CPU, indexed by CPU ID.
uint16_t	_cpuAmount
	The number of CPUs currently identified.

Macro Definition Documentation

CPU_OFFSET_SELF

#define CPU_OFFSET_SELF   0x0

The offset of the self member in the cpu_t structure.

Definition at line 26 of file cpu.h.

CPU_OFFSET_SYSCALL_RSP

#define CPU_OFFSET_SYSCALL_RSP   0x10

The offset of the syscall_ctx_t pointer in the cpu_t structure.

Definition at line 31 of file cpu.h.

CPU_OFFSET_USER_RSP

#define CPU_OFFSET_USER_RSP   0x18

The offset of the userRsp member in the cpu_t structure.

Definition at line 36 of file cpu.h.

CPU_OFFSET_ID

#define CPU_OFFSET_ID   0x8

The offset of the id member in the cpu_t structure.

Needed to access the CPU ID from assembly code.

Definition at line 45 of file cpu.h.

CPU_MAX

#define CPU_MAX   UINT8_MAX

Maximum number of CPUs supported.

Definition at line 50 of file cpu.h.

CPU_ID_BOOTSTRAP

#define CPU_ID_BOOTSTRAP   0

ID of the bootstrap CPU.

Definition at line 55 of file cpu.h.

CPU_ID_INVALID

#define CPU_ID_INVALID   UINT16_MAX

Invalid CPU ID.

Definition at line 60 of file cpu.h.

CPU_STACK_CANARY

#define CPU_STACK_CANARY   0x1234567890ABCDEFULL

CPU stack canary value.

Placed at the bottom of CPU stacks, we then check in the interrupt handler if any of the stacks have overflowed by checking if its canary has been modified.

Definition at line 73 of file cpu.h.

CPU_FOR_EACH

#define CPU_FOR_EACH

(

cpu

)

Value:

    for (cpu_id_t _cpuId = 0; _cpuId < _cpuAmount; _cpuId++) \
        for (cpu = _cpus[_cpuId]; cpu != NULL; cpu = NULL)

Macro to iterate over all CPUs.

The main reason for using this macro is to avoid changes the the internal implementation of how CPUs are stored affecting other parts of the code.

Parameters

cpu	Loop variable, a pointer to the current cpu_t.

Definition at line 214 of file cpu.h.

Typedef Documentation

cpu_id_t

typedef uint16_t cpu_id_t

Type used to identify a CPU.

Definition at line 65 of file cpu.h.

Function Documentation

cpu_init()

void cpu_init

(

cpu_t *

cpu

)

Initializes a CPU structure.

Will note initialize percpu data, use percpu_update() after calling this function.

Parameters

cpu	The CPU structure to initialize.

Definition at line 27 of file cpu.c.

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cpu_stacks_overflow_check()

void cpu_stacks_overflow_check

(

void

)

Checks the current CPU for stack overflows.

Checks the canary values at the bottom of each CPU stack and if its been modified panics.

Definition at line 83 of file cpu.c.

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cpu_halt_others()

uint64_t cpu_halt_others

(

void

)

Halts all other CPUs.

Returns

On success, 0. On failure, ERR and errno is set.

Definition at line 115 of file cpu.c.

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cpu_interrupt_stack_top()

uintptr_t cpu_interrupt_stack_top

(

void

)

Gets the top of the interrupt stack for the current CPU.

Usefull as we might need to retrieve the interrupt stack in assembly, so this avoid code duplication.

Returns

The top of the interrupt stack.

Definition at line 124 of file cpu.c.

cpu_amount()

static uint16_t cpu_amount ( void  )

inlinestatic

Gets the number of identified CPUs.

Use this over _cpuAmount.

Returns

The number of identified CPUs.

Definition at line 168 of file cpu.h.

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cpu_get_by_id()

static cpu_t * cpu_get_by_id ( cpu_id_t  id )

inlinestatic

Gets a CPU structure by its ID.

Parameters

id	The ID of the CPU to get.

Returns

A pointer to the CPU structure, or NULL if no CPU with the given ID exists.

Definition at line 179 of file cpu.h.

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cpu_get_next()

static cpu_t * cpu_get_next ( cpu_t *  current )

inlinestatic

Gets the next CPU in the CPU array.

Wraps around to the first CPU if the current CPU is the last one.

Parameters

current

The current CPU.

Returns

A pointer to the next CPU.

Definition at line 196 of file cpu.h.

Variable Documentation

_cpus

cpu_t* _cpus[CPU_MAX]

extern

Array of pointers to cpu_t structures for each CPU, indexed by CPU ID.

We make this global since its accessed very frequently, so its a slight optimization.

Definition at line 24 of file cpu.c.

_cpuAmount

uint16_t _cpuAmount

extern

The number of CPUs currently identified.

Use cpu_amount() over this variable.

Definition at line 25 of file cpu.c.