Module percpu 

Per-CPU data (x86_64)

Minimal per-CPU tracking for SMP bring-up. This keeps CPU identity, online state, and per-CPU kernel stack top pointers.

Structs

PerCpu

Per-CPU state.

PerCpuArch

Minimal per-CPU block accessed from assembly via GS base.

Constants

KERNEL_RSP_OFFSET

MAX_CPUS

Maximum number of CPUs supported for now.

USER_RSP_OFFSET

Offsets used by the SYSCALL entry (must match PerCpuArch layout). Note: cpu_index is at offset 0 (8 bytes).

Functions

apic_id_by_cpu_index

Get the APIC ID for a given CPU index, or None if not present.

cpu_count

Get the total number of CPUs that have been registered.

cpu_index_by_apic

Find a CPU index by APIC ID.

cpu_index_from_gs

Resolve current CPU index from GS base (compatibility).

current_cpu_index

Resolve current CPU index via a GS-relative load from offset 0.

current_cpu_index_fast

Alias for current_cpu_index.

get_cpu_count

Get the total number of CPUs (public alias for OSTD compatibility).

init_boot_cpu

Initialize the boot CPU (BSP) entry.

init_gs_base

Initialize GS base for this CPU to point at its per-CPU block.

is_preemptible

Returns true if preemption is currently allowed on this CPU (preempt_count == 0).

kernel_stack_top

Get the per-CPU kernel stack top for the given CPU index.

mark_online_by_apic

Mark a CPU as online by APIC ID.

mark_tlb_ready_current

Mark current CPU as ready to handle TLB shootdown IPIs.

percpu

Access the per-CPU array (read-only).

preempt_disable

Increment the preemption-disable depth for the current CPU. When depth > 0, the scheduler will not preempt this CPU.

preempt_enable

Decrement the preemption-disable depth for the current CPU. Must be paired with exactly one prior call to preempt_disable.

register_cpu

Register a new CPU by APIC ID, returning its CPU index.

set_kernel_rsp_current

Set the per-CPU SYSCALL kernel RSP for the current CPU.

set_kernel_rsp_for_cpu

Set the per-CPU SYSCALL kernel RSP (used by syscall entry).

set_kernel_stack_top

Set the per-CPU kernel stack top for the given CPU index.

tlb_ready

Returns true iff CPU index is online and ready for TLB shootdown.