add percpu support

[li041]

• This change has not been fully tested yet. Currently it has only been verified on qemu-gicv3, qemu-aia, and rk3588.
• I would appreciate it if other developers could help test this on additional platforms.
• The main purpose of this PR is to introduce the percpu crate to better abstract per-CPU variables, instead of relying on global Vec.
• Feedback on both correctness and design is very welcome.

[Copilot]

Pull request overview

This PR refactors the hypervisor to use the external percpu crate for managing per-CPU variables, replacing the previous approach that relied on global Vec collections. The main changes include renaming the percpu module to cpu_data, introducing per-CPU event queues, and adding linker script sections to support the percpu infrastructure.

• Introduces the external percpu crate (v0.2) to abstract per-CPU variables
• Refactors event management from a global Vec-based EventManager to per-CPU VecDeque instances
• Adds .percpu sections to all platform linker scripts with proper sizing

Reviewed changes

Copilot reviewed 52 out of 54 changed files in this pull request and generated 12 comments.

Show a summary per file

File	Description
src/cpu_data.rs	New module containing PerCpu struct and related functions (renamed from percpu module)
src/event.rs	Refactored to use percpu-based event queues instead of global EventManager with Vec
src/main.rs	Added percpu initialization calls; removed event::init() call
src/zone.rs, src/pci/pci.rs, src/memory/mmio.rs, src/logging.rs, src/hypercall/mod.rs	Updated imports from crate::percpu to crate::cpu_data
src/device/irqchip/**/*.rs	Updated imports from crate::percpu to crate::cpu_data across all irqchip implementations
src/arch/**/*.rs	Updated imports from crate::percpu to crate::cpu_data across all architectures
platform/**/linker.ld	Added .percpu section definitions with CPU_NUM constant for sizing percpu areas
Cargo.toml	Added percpu crate dependency with arm-el2 feature
Cargo.lock	Added percpu and percpu_macros dependencies

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[Copilot]

The percpu dependency is configured with the "arm-el2" feature unconditionally in the general dependencies section. This feature is specific to AArch64's Exception Level 2 (hypervisor mode) and should not be enabled for other architectures like riscv64, loongarch64, or x86_64. Consider either making this a target-specific dependency under [target.'cfg(target_arch = "aarch64")'.dependencies], or using cfg-based features to conditionally enable the appropriate percpu features for each architecture.

[ForeverYolo]

Can you explain why we need to do this?

[li041]

Can you explain why we need to do this?

less code, unified per-CPU abstraction, possible performance improvement