Kernel: Move Scheduler current time method to the TimeManagement code

2 files changed, 24 insertions, 0 deletions

diff --git a/Kernel/Time/TimeManagement.cpp b/Kernel/Time/TimeManagement.cpp
index 4bf25c7e20..99318a918e 100644
--- a/Kernel/Time/TimeManagement.cpp
+++ b/Kernel/Time/TimeManagement.cpp
@@ -17,6 +17,7 @@
 #    include <Kernel/Arch/x86/common/Interrupts/APIC.h>
 #    include <Kernel/Arch/x86/common/RTC.h>
 #endif
+#include <Kernel/Arch/CurrentTime.h>
 #include <Kernel/CommandLine.h>
 #include <Kernel/Firmware/ACPI/Parser.h>
 #include <Kernel/PerformanceManager.h>
@@ -40,6 +41,22 @@ TimeManagement& TimeManagement::the()
     return *s_the;
 }
 
+// The s_scheduler_specific_current_time function provides a current time for scheduling purposes,
+// which may not necessarily relate to wall time
+static u64 (*s_scheduler_current_time)();
+
+static u64 current_time_monotonic()
+{
+    // We always need a precise timestamp here, we cannot rely on a coarse timestamp
+    return (u64)TimeManagement::the().monotonic_time(TimePrecision::Precise).to_nanoseconds();
+}
+
+u64 TimeManagement::scheduler_current_time()
+{
+    VERIFY(s_scheduler_current_time);
+    return s_scheduler_current_time();
+}
+
 ErrorOr<void> TimeManagement::validate_clock_id(clockid_t clock_id)
 {
     switch (clock_id) {
@@ -163,6 +180,11 @@ UNMAP_AFTER_INIT void TimeManagement::initialize([[maybe_unused]] u32 cpu)
             apic_timer->enable_local_timer();
         }
     }
+    auto* possible_arch_specific_current_time_function = optional_current_time();
+    if (possible_arch_specific_current_time_function)
+        s_scheduler_current_time = possible_arch_specific_current_time_function;
+    else
+        s_scheduler_current_time = current_time_monotonic;
 #endif
 }
 
diff --git a/Kernel/Time/TimeManagement.h b/Kernel/Time/TimeManagement.h
index d2973f6f86..f5e20d0f66 100644
--- a/Kernel/Time/TimeManagement.h
+++ b/Kernel/Time/TimeManagement.h
@@ -37,6 +37,8 @@ public:
     static bool is_initialized();
     static TimeManagement& the();
 
+    static u64 scheduler_current_time();
+
     static ErrorOr<void> validate_clock_id(clockid_t);
     Time current_time(clockid_t) const;
     Time monotonic_time(TimePrecision = TimePrecision::Coarse) const;