Introduce CPU clock and CPU timer

kernel/aster-nix/src/time/clocks/cpu_clock.rs

@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: MPL-2.0
+
+use alloc::sync::Arc;
+use core::time::Duration;
+
+use aster_frame::sync::SpinLock;
+
+use crate::time::Clock;
+
+/// A clock used to record the CPU time for processes and threads.
+pub struct CpuClock {
+    time: SpinLock<Duration>,
+}
+
+/// A profiling clock that contains a user CPU clock and a kernel CPU clock.
+/// These two clocks record the CPU time in user mode and kernel mode respectively.
+/// Reading this clock directly returns the sum of both times.
+pub struct ProfClock {
+    user_clock: Arc<CpuClock>,
+    kernel_clock: Arc<CpuClock>,
+}
+
+impl CpuClock {
+    /// Creates a new `CpuClock`. The recorded time is initialized to 0.
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            time: SpinLock::new(Duration::ZERO),
+        })
+    }
+
+    /// Adds `interval` to the original recorded time to update the `CpuClock`.
+    pub fn add_time(&self, interval: Duration) {
+        *self.time.lock_irq_disabled() += interval;
+    }
+}
+
+impl Clock for CpuClock {
+    fn read_time(&self) -> Duration {
+        *self.time.lock_irq_disabled()
+    }
+}
+
+impl ProfClock {
+    /// Creates a new `ProfClock`. The recorded time is initialized to 0.
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            user_clock: CpuClock::new(),
+            kernel_clock: CpuClock::new(),
+        })
+    }
+
+    /// Returns a reference to the user CPU clock in this profiling clock.
+    pub fn user_clock(&self) -> &Arc<CpuClock> {
+        &self.user_clock
+    }
+
+    /// Returns a reference to the kernel CPU clock in this profiling clock.
+    pub fn kernel_clock(&self) -> &Arc<CpuClock> {
+        &self.kernel_clock
+    }
+}
+
+impl Clock for ProfClock {
+    fn read_time(&self) -> Duration {
+        self.user_clock.read_time() + self.kernel_clock.read_time()
+    }
+}

kernel/aster-nix/src/time/clocks/mod.rs

@@ -1,7 +1,9 @@
 // SPDX-License-Identifier: MPL-2.0
 
+pub use cpu_clock::*;
 pub use system_wide::*;
 
+mod cpu_clock;
 mod system_wide;
 
 pub(super) fn init() {

kernel/aster-nix/src/time/clocks/system_wide.rs

@@ -124,6 +124,11 @@ impl BootTimeClock {
     pub fn get() -> &'static Arc<BootTimeClock> {
         CLOCK_BOOTTIME_INSTANCE.get().unwrap()
     }
+
+    /// Get the cpu-local system-wide `TimerManager` singleton of this clock.
+    pub fn timer_manager() -> &'static Arc<TimerManager> {
+        CLOCK_BOOTTIME_MANAGER.get().unwrap()
+    }
 }
 
 impl Clock for JiffiesClock {
@@ -232,7 +237,7 @@ define_system_clocks! {
     CLOCK_BOOTTIME          => BootTimeClock,
 }
 
-define_timer_managers![CLOCK_REALTIME, CLOCK_MONOTONIC,];
+define_timer_managers![CLOCK_REALTIME, CLOCK_MONOTONIC, CLOCK_BOOTTIME,];
 
 /// Init the system-wide clocks.
 fn init_system_wide_clocks() {