Move CpuSet out of ostd::arch and implement this_cpu

Co-authored-by: Chuandong Li <lichuand@pku.edu.cn>

ostd/src/arch/x86/boot/smp.rs

@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: MPL-2.0
+
+//! Multiprocessor Boot Support
+//!
+//! The MP initialization protocol defines two classes of processors:
+//! the bootstrap processor (BSP) and the application processors (APs).
+//! Following a power-up or RESET of an MP system, system hardware dynamically
+//! selects one of the processors on the system bus as the BSP. The remaining
+//! processors are designated as APs.
+//!
+//! The BSP executes the BIOS's boot-strap code to configure the APIC environment,
+//! sets up system-wide data structures. Up to now, BSP has completed most of the
+//! initialization of the OS, but APs has not been awakened.
+
+use acpi::platform::{PlatformInfo, ProcessorInfo};
+
+use crate::arch::x86::kernel::acpi::ACPI_TABLES;
+
+/// Get processor information
+///
+/// This function needs to be called after the OS initializes the ACPI table.
+pub(crate) fn get_processor_info() -> Option<ProcessorInfo> {
+    if !ACPI_TABLES.is_completed() {
+        return None;
+    }
+    Some(
+        PlatformInfo::new(&*ACPI_TABLES.get().unwrap().lock())
+            .unwrap()
+            .processor_info
+            .unwrap(),
+    )
+}