Make PercpuBlock const constructable

src/arch/aarch64/device/mod.rs

@@ -51,5 +51,10 @@ pub unsafe fn init_devicetree(fdt: &Fdt) {
     }
 }
 
-#[derive(Default)]
 pub struct ArchPercpuMisc;
+
+impl ArchPercpuMisc {
+    pub const fn default() -> Self {
+        Self
+    }
+}

src/arch/riscv64/device/mod.rs

@@ -101,5 +101,10 @@ pub unsafe fn init_noncore() {
     }
 }
 
-#[derive(Default)]
 pub struct ArchPercpuMisc;
+
+impl ArchPercpuMisc {
+    pub const fn default() -> Self {
+        Self
+    }
+}

src/arch/x86_shared/device/mod.rs

@@ -81,9 +81,18 @@ pub unsafe fn init_ap() {
     }
 }
 
-#[derive(Default)]
 pub struct ArchPercpuMisc {
     pub apic_id_opt: Cell<Option<local_apic::ApicId>>,
     #[cfg(feature = "x86_kvm_pv")]
     pub tsc_info: tsc::TscPercpu,
 }
+
+impl ArchPercpuMisc {
+    pub const fn default() -> Self {
+        Self {
+            apic_id_opt: Cell::new(None),
+            #[cfg(feature = "x86_kvm_pv")]
+            tsc_info: tsc::TscPercpu::default(),
+        }
+    }
+}

src/arch/x86_shared/device/tsc.rs

@@ -46,8 +46,8 @@ pub struct TscPercpu {
     vcpu_page: Cell<*const PvclockVcpuTimeInfo>,
     prev: Cell<u128>,
 }
-impl Default for TscPercpu {
-    fn default() -> Self {
+impl TscPercpu {
+    pub const fn default() -> Self {
         Self {
             vcpu_page: Cell::new(core::ptr::null()),
             prev: Cell::new(0),

src/context/switch.rs

@@ -315,7 +315,6 @@ pub fn switch() -> SwitchResult {
 ///
 /// This struct contains information such as the idle context, current context, and PIT tick counts,
 /// as well as fields required for managing ptrace sessions and signals.
-#[derive(Default)]
 pub struct ContextSwitchPercpu {
     switch_result: Cell<Option<SwitchResultInner>>,
     pit_ticks: Cell<usize>,
@@ -329,6 +328,16 @@ pub struct ContextSwitchPercpu {
 }
 
 impl ContextSwitchPercpu {
+    pub const fn default() -> Self {
+        Self {
+            switch_result: Cell::new(None),
+            pit_ticks: Cell::new(0),
+            current_ctxt: RefCell::new(None),
+            idle_ctxt: RefCell::new(None),
+            being_sigkilled: Cell::new(false),
+        }
+    }
+
     /// Applies a function to the current context, allowing controlled access.
     ///
     /// # Parameters

src/cpu_stats.rs

@@ -44,6 +44,19 @@ pub struct CpuStats {
     state: AtomicU8,
 }
 
+impl CpuStats {
+    pub const fn default() -> Self {
+        Self {
+            user: AtomicUsize::new(0),
+            nice: AtomicUsize::new(0),
+            kernel: AtomicUsize::new(0),
+            idle: AtomicUsize::new(0),
+            irq: AtomicUsize::new(0),
+            state: AtomicU8::new(0),
+        }
+    }
+}
+
 pub struct CpuStatsData {
     /// Number of ticks spent on userspace contexts
     pub user: usize,

src/percpu.rs

@@ -8,6 +8,7 @@ use rmm::Arch;
 use syscall::PtraceFlags;
 
 use crate::{
+    arch::device::ArchPercpuMisc,
     context::{empty_cr3, memory::AddrSpaceWrapper, switch::ContextSwitchPercpu},
     cpu_set::{LogicalCpuId, MAX_CPU_COUNT},
     cpu_stats::CpuStats,
@@ -167,14 +168,14 @@ pub unsafe fn switch_arch_hook() {
     }
 }
 impl PercpuBlock {
-    pub fn init(cpu_id: LogicalCpuId) -> Self {
+    pub const fn init(cpu_id: LogicalCpuId) -> Self {
         Self {
             cpu_id,
-            switch_internals: Default::default(),
+            switch_internals: ContextSwitchPercpu::default(),
             current_addrsp: RefCell::new(None),
             new_addrsp_tmp: Cell::new(None),
             wants_tlb_shootdown: AtomicBool::new(false),
-            ptrace_flags: Cell::new(Default::default()),
+            ptrace_flags: Cell::new(PtraceFlags::empty()),
             ptrace_session: RefCell::new(None),
             inside_syscall: Cell::new(false),
 
@@ -183,7 +184,7 @@ impl PercpuBlock {
             #[cfg(feature = "profiling")]
             profiling: None,
 
-            misc_arch_info: Default::default(),
+            misc_arch_info: ArchPercpuMisc::default(),
 
             stats: CpuStats::default(),
         }

src/syscall/debug.rs

@@ -196,12 +196,21 @@ pub struct SyscallDebugInfo {
     accumulated_time: u128,
     do_debug: bool,
 }
-#[cfg(feature = "syscall_debug")]
 impl SyscallDebugInfo {
+    pub const fn default() -> Self {
+        Self {
+            this_switch_time: 0,
+            accumulated_time: 0,
+            do_debug: false,
+        }
+    }
+
+    #[cfg(feature = "syscall_debug")]
     pub fn on_switch_from(&mut self) {
         let now = crate::time::monotonic();
         self.accumulated_time += now - core::mem::replace(&mut self.this_switch_time, now);
     }
+    #[cfg(feature = "syscall_debug")]
     pub fn on_switch_to(&mut self) {
         self.this_switch_time = crate::time::monotonic();
     }