yuzu/src/core/hle/kernel/scheduler.h
2019-10-15 11:55:04 -04:00

185 lines
5.4 KiB
C++

// Copyright 2018 yuzu emulator team
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <mutex>
#include <vector>
#include "common/common_types.h"
#include "common/multi_level_queue.h"
#include "core/hle/kernel/object.h"
#include "core/hle/kernel/thread.h"
namespace Core {
class ARM_Interface;
class System;
} // namespace Core
namespace Kernel {
class Process;
class GlobalScheduler final {
public:
static constexpr u32 NUM_CPU_CORES = 4;
GlobalScheduler() {
reselection_pending = false;
}
~GlobalScheduler();
/// Adds a new thread to the scheduler
void AddThread(SharedPtr<Thread> thread);
/// Removes a thread from the scheduler
void RemoveThread(Thread* thread);
/// Returns a list of all threads managed by the scheduler
const std::vector<SharedPtr<Thread>>& GetThreadList() const {
return thread_list;
}
void Suggest(u32 priority, u32 core, Thread* thread) {
suggested_queue[core].add(thread, priority);
}
void Unsuggest(u32 priority, u32 core, Thread* thread) {
suggested_queue[core].remove(thread, priority);
}
void Schedule(u32 priority, u32 core, Thread* thread) {
ASSERT_MSG(thread->GetProcessorID() == core,
"Thread must be assigned to this core.");
scheduled_queue[core].add(thread, priority);
}
void SchedulePrepend(u32 priority, u32 core, Thread* thread) {
ASSERT_MSG(thread->GetProcessorID() == core,
"Thread must be assigned to this core.");
scheduled_queue[core].add(thread, priority, false);
}
void Reschedule(u32 priority, u32 core, Thread* thread) {
scheduled_queue[core].remove(thread, priority);
scheduled_queue[core].add(thread, priority);
}
void Unschedule(u32 priority, u32 core, Thread* thread) {
scheduled_queue[core].remove(thread, priority);
}
void TransferToCore(u32 priority, s32 destination_core, Thread* thread) {
bool schedulable = thread->GetPriority() < THREADPRIO_COUNT;
s32 source_core = thread->GetProcessorID();
if (source_core == destination_core || !schedulable)
return;
thread->SetProcessorID(destination_core);
if (source_core >= 0)
Unschedule(priority, source_core, thread);
if (destination_core >= 0) {
Unsuggest(priority, destination_core, thread);
Schedule(priority, destination_core, thread);
}
if (source_core >= 0)
Suggest(priority, source_core, thread);
}
void UnloadThread(s32 core);
void SelectThreads();
void SelectThread(u32 core);
bool HaveReadyThreads(u32 core_id) {
return !scheduled_queue[core_id].empty();
}
void YieldThread(Thread* thread);
void YieldThreadAndBalanceLoad(Thread* thread);
void YieldThreadAndWaitForLoadBalancing(Thread* thread);
u32 CpuCoresCount() const {
return NUM_CPU_CORES;
}
void SetReselectionPending() {
reselection_pending.store(true, std::memory_order_release);
}
bool IsReselectionPending() {
return reselection_pending.load(std::memory_order_acquire);
}
private:
void AskForReselectionOrMarkRedundant(Thread* current_thread, Thread* winner);
static constexpr u32 min_regular_priority = 2;
std::array<Common::MultiLevelQueue<Thread*, THREADPRIO_COUNT>, NUM_CPU_CORES> scheduled_queue;
std::array<Common::MultiLevelQueue<Thread*, THREADPRIO_COUNT>, NUM_CPU_CORES> suggested_queue;
std::atomic<bool> reselection_pending;
/// Lists all thread ids that aren't deleted/etc.
std::vector<SharedPtr<Thread>> thread_list;
};
class Scheduler final {
public:
explicit Scheduler(Core::System& system, Core::ARM_Interface& cpu_core, const u32 id);
~Scheduler();
/// Returns whether there are any threads that are ready to run.
bool HaveReadyThreads() const;
/// Reschedules to the next available thread (call after current thread is suspended)
void TryDoContextSwitch();
void UnloadThread();
void SelectThreads();
/// Gets the current running thread
Thread* GetCurrentThread() const;
Thread* GetSelectedThread() const;
/// Gets the timestamp for the last context switch in ticks.
u64 GetLastContextSwitchTicks() const;
bool ContextSwitchPending() const {
return context_switch_pending;
}
private:
friend class GlobalScheduler;
/**
* Switches the CPU's active thread context to that of the specified thread
* @param new_thread The thread to switch to
*/
void SwitchContext();
/**
* Called on every context switch to update the internal timestamp
* This also updates the running time ticks for the given thread and
* process using the following difference:
*
* ticks += most_recent_ticks - last_context_switch_ticks
*
* The internal tick timestamp for the scheduler is simply the
* most recent tick count retrieved. No special arithmetic is
* applied to it.
*/
void UpdateLastContextSwitchTime(Thread* thread, Process* process);
SharedPtr<Thread> current_thread = nullptr;
SharedPtr<Thread> selected_thread = nullptr;
Core::System& system;
Core::ARM_Interface& cpu_core;
u64 last_context_switch_time = 0;
u64 idle_selection_count = 0;
const u32 id;
bool context_switch_pending = false;
};
} // namespace Kernel