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nt-lite/code/kernel/ke_sched.h
T

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1.6 KiB
C

#pragma once
// ke_sched.h - Multi-Level Feedback Queue scheduler
// Three run queues (Low / Normal / High). IRQ 0 drives KeSchedulerTick.
#include <ke_thread.h>
#define QUANTUM_MS 10 // base time slice in milliseconds
typedef struct KE_SCHED_STATS {
uint64_t Ticks;
uint64_t ContextSwitches;
uint64_t KeepCurrentDecisions;
uint64_t IdleSelections;
uint64_t Demotions;
uint64_t AgingPromotions;
} KE_SCHED_STATS;
// Called once by KernelMain before any threads are created.
void KeInitializeScheduler(void);
// Add / remove a thread from the run queues.
void KeReadyThread(THREAD* thread);
void KeUnreadyThread(THREAD* thread);
// Called from the timer ISR every QUANTUM_MS. This only performs timer
// accounting and requests a reschedule; the actual context switch happens from
// KiExitInterrupt after the IRQ handler has returned and EOI has been sent.
void KeSchedulerTick(void);
// Internal scheduler hooks used by the interrupt-exit path. KiRequestReschedule
// is cheap and can be called from interrupt context. KiScheduleFromInterrupt
// consumes the pending request and performs the context switch, if needed.
void KiRequestReschedule(void);
int KiIsReschedulePending(void);
void KiScheduleFromInterrupt(void);
// Voluntarily yield the CPU. Picks the next runnable thread immediately.
__declspec(dllexport) void KeYield(void);
void KeGetSchedulerStats(KE_SCHED_STATS* out);
// Returns the thread currently running on this CPU (reads GS:[0]).
THREAD* KeGetCurrentThread(void);
// Set the current-thread GS slot. Called once per CPU at boot.
void KeSetCurrentThread(THREAD* thread);