kernel: fix issues with single core mode

This commit is contained in:
Liam 2022-07-05 23:27:25 -04:00
parent 0624c880bd
commit 21945ae127
9 changed files with 229 additions and 193 deletions

View File

@ -42,14 +42,6 @@ void CpuManager::Shutdown() {
}
}
void CpuManager::GuestActivateFunction() {
if (is_multicore) {
MultiCoreGuestActivate();
} else {
SingleCoreGuestActivate();
}
}
void CpuManager::GuestThreadFunction() {
if (is_multicore) {
MultiCoreRunGuestThread();
@ -58,21 +50,16 @@ void CpuManager::GuestThreadFunction() {
}
}
void CpuManager::ShutdownThreadFunction() {
ShutdownThread();
void CpuManager::IdleThreadFunction() {
if (is_multicore) {
MultiCoreRunIdleThread();
} else {
SingleCoreRunIdleThread();
}
}
void CpuManager::WaitForAndHandleInterrupt() {
auto& kernel = system.Kernel();
auto& physical_core = kernel.CurrentPhysicalCore();
ASSERT(Kernel::GetCurrentThread(kernel).GetDisableDispatchCount() == 1);
if (!physical_core.IsInterrupted()) {
physical_core.Idle();
}
HandleInterrupt();
void CpuManager::ShutdownThreadFunction() {
ShutdownThread();
}
void CpuManager::HandleInterrupt() {
@ -86,26 +73,10 @@ void CpuManager::HandleInterrupt() {
/// MultiCore ///
///////////////////////////////////////////////////////////////////////////////
void CpuManager::MultiCoreGuestActivate() {
// Similar to the HorizonKernelMain callback in HOS
auto& kernel = system.Kernel();
auto* scheduler = kernel.CurrentScheduler();
scheduler->Activate();
UNREACHABLE();
}
void CpuManager::MultiCoreRunGuestThread() {
// Similar to UserModeThreadStarter in HOS
auto& kernel = system.Kernel();
auto* thread = kernel.GetCurrentEmuThread();
thread->EnableDispatch();
MultiCoreRunGuestLoop();
}
void CpuManager::MultiCoreRunGuestLoop() {
auto& kernel = system.Kernel();
kernel.CurrentScheduler()->OnThreadStart();
while (true) {
auto* physical_core = &kernel.CurrentPhysicalCore();
@ -118,17 +89,105 @@ void CpuManager::MultiCoreRunGuestLoop() {
}
}
void CpuManager::MultiCoreRunIdleThread() {
// Not accurate to HOS. Remove this entire method when singlecore is removed.
// See notes in KScheduler::ScheduleImpl for more information about why this
// is inaccurate.
auto& kernel = system.Kernel();
kernel.CurrentScheduler()->OnThreadStart();
while (true) {
auto& physical_core = kernel.CurrentPhysicalCore();
if (!physical_core.IsInterrupted()) {
physical_core.Idle();
}
HandleInterrupt();
}
}
///////////////////////////////////////////////////////////////////////////////
/// SingleCore ///
///////////////////////////////////////////////////////////////////////////////
void CpuManager::SingleCoreGuestActivate() {}
void CpuManager::SingleCoreRunGuestThread() {
auto& kernel = system.Kernel();
kernel.CurrentScheduler()->OnThreadStart();
void CpuManager::SingleCoreRunGuestThread() {}
while (true) {
auto* physical_core = &kernel.CurrentPhysicalCore();
if (!physical_core->IsInterrupted()) {
physical_core->Run();
physical_core = &kernel.CurrentPhysicalCore();
}
void CpuManager::SingleCoreRunGuestLoop() {}
kernel.SetIsPhantomModeForSingleCore(true);
system.CoreTiming().Advance();
kernel.SetIsPhantomModeForSingleCore(false);
void CpuManager::PreemptSingleCore(bool from_running_enviroment) {}
PreemptSingleCore();
HandleInterrupt();
}
}
void CpuManager::SingleCoreRunIdleThread() {
auto& kernel = system.Kernel();
kernel.CurrentScheduler()->OnThreadStart();
while (true) {
PreemptSingleCore(false);
system.CoreTiming().AddTicks(1000U);
idle_count++;
HandleInterrupt();
}
}
void CpuManager::PreemptSingleCore(bool from_running_environment) {
{
auto& kernel = system.Kernel();
auto& scheduler = kernel.Scheduler(current_core);
Kernel::KThread* current_thread = scheduler.GetSchedulerCurrentThread();
if (idle_count >= 4 || from_running_environment) {
if (!from_running_environment) {
system.CoreTiming().Idle();
idle_count = 0;
}
kernel.SetIsPhantomModeForSingleCore(true);
system.CoreTiming().Advance();
kernel.SetIsPhantomModeForSingleCore(false);
}
current_core.store((current_core + 1) % Core::Hardware::NUM_CPU_CORES);
system.CoreTiming().ResetTicks();
scheduler.Unload(scheduler.GetSchedulerCurrentThread());
auto& next_scheduler = kernel.Scheduler(current_core);
// Disable dispatch. We're about to preempt this thread.
Kernel::KScopedDisableDispatch dd{kernel};
Common::Fiber::YieldTo(current_thread->GetHostContext(), *next_scheduler.GetSwitchFiber());
}
// We've now been scheduled again, and we may have exchanged schedulers.
// Reload the scheduler in case it's different.
{
auto& scheduler = system.Kernel().Scheduler(current_core);
scheduler.Reload(scheduler.GetSchedulerCurrentThread());
if (!scheduler.IsIdle()) {
idle_count = 0;
}
}
}
void CpuManager::GuestActivate() {
// Similar to the HorizonKernelMain callback in HOS
auto& kernel = system.Kernel();
auto* scheduler = kernel.CurrentScheduler();
scheduler->Activate();
UNREACHABLE();
}
void CpuManager::ShutdownThread() {
auto& kernel = system.Kernel();
@ -168,20 +227,11 @@ void CpuManager::RunThread(std::size_t core) {
}
auto& kernel = system.Kernel();
auto& scheduler = *kernel.CurrentScheduler();
auto* thread = scheduler.GetSchedulerCurrentThread();
Kernel::SetCurrentThread(kernel, thread);
auto* main_thread = Kernel::KThread::Create(kernel);
main_thread->SetName(fmt::format("MainThread:{}", core));
ASSERT(Kernel::KThread::InitializeMainThread(system, main_thread, static_cast<s32>(core))
.IsSuccess());
auto* idle_thread = Kernel::KThread::Create(kernel);
ASSERT(Kernel::KThread::InitializeIdleThread(system, idle_thread, static_cast<s32>(core))
.IsSuccess());
kernel.SetCurrentEmuThread(main_thread);
kernel.CurrentScheduler()->Initialize(idle_thread);
Common::Fiber::YieldTo(data.host_context, *main_thread->GetHostContext());
Common::Fiber::YieldTo(data.host_context, *thread->GetHostContext());
}
} // namespace Core

View File

@ -48,12 +48,11 @@ public:
gpu_barrier->Sync();
}
void WaitForAndHandleInterrupt();
void Initialize();
void Shutdown();
std::function<void()> GetGuestActivateFunc() {
return [this] { GuestActivateFunction(); };
return [this] { GuestActivate(); };
}
std::function<void()> GetGuestThreadFunc() {
return [this] { GuestThreadFunction(); };
@ -72,21 +71,19 @@ public:
}
private:
void GuestActivateFunction();
void GuestThreadFunction();
void IdleThreadFunction();
void ShutdownThreadFunction();
void MultiCoreGuestActivate();
void MultiCoreRunGuestThread();
void MultiCoreRunGuestLoop();
void MultiCoreRunIdleThread();
void SingleCoreGuestActivate();
void SingleCoreRunGuestThread();
void SingleCoreRunGuestLoop();
void SingleCoreRunIdleThread();
static void ThreadStart(std::stop_token stop_token, CpuManager& cpu_manager, std::size_t core);
void GuestActivate();
void HandleInterrupt();
void ShutdownThread();
void RunThread(std::size_t core);

View File

@ -42,11 +42,6 @@ void GlobalSchedulerContext::PreemptThreads() {
for (u32 core_id = 0; core_id < Core::Hardware::NUM_CPU_CORES; core_id++) {
const u32 priority = preemption_priorities[core_id];
KScheduler::RotateScheduledQueue(kernel, core_id, priority);
// Signal an interrupt occurred. For core 3, this is a certainty, as preemption will result
// in the rotator thread being scheduled. For cores 0-2, this is to simulate or system
// interrupts that may have occurred.
kernel.PhysicalCore(core_id).Interrupt();
}
}

View File

@ -28,9 +28,9 @@ static void IncrementScheduledCount(Kernel::KThread* thread) {
}
KScheduler::KScheduler(KernelCore& kernel_) : kernel{kernel_} {
m_idle_stack = std::make_shared<Common::Fiber>([this] {
m_switch_fiber = std::make_shared<Common::Fiber>([this] {
while (true) {
ScheduleImplOffStack();
ScheduleImplFiber();
}
});
@ -60,9 +60,9 @@ void KScheduler::DisableScheduling(KernelCore& kernel) {
void KScheduler::EnableScheduling(KernelCore& kernel, u64 cores_needing_scheduling) {
ASSERT(GetCurrentThread(kernel).GetDisableDispatchCount() >= 1);
auto* scheduler = kernel.CurrentScheduler();
auto* scheduler{kernel.CurrentScheduler()};
if (!scheduler) {
if (!scheduler || kernel.IsPhantomModeForSingleCore()) {
// HACK: we cannot schedule from this thread, it is not a core thread
RescheduleCores(kernel, cores_needing_scheduling);
if (GetCurrentThread(kernel).GetDisableDispatchCount() == 1) {
@ -125,9 +125,9 @@ void KScheduler::RescheduleCurrentCoreImpl() {
}
}
void KScheduler::Initialize(KThread* idle_thread) {
void KScheduler::Initialize(KThread* main_thread, KThread* idle_thread, s32 core_id) {
// Set core ID/idle thread/interrupt task manager.
m_core_id = GetCurrentCoreId(kernel);
m_core_id = core_id;
m_idle_thread = idle_thread;
// m_state.idle_thread_stack = m_idle_thread->GetStackTop();
// m_state.interrupt_task_manager = &kernel.GetInterruptTaskManager();
@ -142,10 +142,10 @@ void KScheduler::Initialize(KThread* idle_thread) {
// Bind interrupt handler.
// kernel.GetInterruptManager().BindHandler(
// GetSchedulerInterruptHandler(kernel), KInterruptName::Scheduler, m_core_id,
// KInterruptController::PriorityLevel_Scheduler, false, false);
// KInterruptController::PriorityLevel::Scheduler, false, false);
// Set the current thread.
m_current_thread = GetCurrentThreadPointer(kernel);
m_current_thread = main_thread;
}
void KScheduler::Activate() {
@ -156,6 +156,10 @@ void KScheduler::Activate() {
RescheduleCurrentCore();
}
void KScheduler::OnThreadStart() {
GetCurrentThread(kernel).EnableDispatch();
}
u64 KScheduler::UpdateHighestPriorityThread(KThread* highest_thread) {
if (KThread* prev_highest_thread = m_state.highest_priority_thread;
prev_highest_thread != highest_thread) [[likely]] {
@ -372,37 +376,30 @@ void KScheduler::ScheduleImpl() {
}
// The highest priority thread is not the same as the current thread.
// Switch to the idle thread stack and continue executing from there.
m_idle_cur_thread = cur_thread;
m_idle_highest_priority_thread = highest_priority_thread;
Common::Fiber::YieldTo(cur_thread->host_context, *m_idle_stack);
// Jump to the switcher and continue executing from there.
m_switch_cur_thread = cur_thread;
m_switch_highest_priority_thread = highest_priority_thread;
m_switch_from_schedule = true;
Common::Fiber::YieldTo(cur_thread->host_context, *m_switch_fiber);
// Returning from ScheduleImpl occurs after this thread has been scheduled again.
}
void KScheduler::ScheduleImplOffStack() {
KThread* const cur_thread{m_idle_cur_thread};
KThread* highest_priority_thread{m_idle_highest_priority_thread};
void KScheduler::ScheduleImplFiber() {
KThread* const cur_thread{m_switch_cur_thread};
KThread* highest_priority_thread{m_switch_highest_priority_thread};
// Get a reference to the current thread's stack parameters.
auto& sp{cur_thread->GetStackParameters()};
// If we're not coming from scheduling (i.e., we came from SC preemption),
// we should restart the scheduling loop directly. Not accurate to HOS.
if (!m_switch_from_schedule) {
goto retry;
}
// Mark that we are not coming from scheduling anymore.
m_switch_from_schedule = false;
// Save the original thread context.
{
auto& physical_core = kernel.System().CurrentPhysicalCore();
auto& cpu_core = physical_core.ArmInterface();
cpu_core.SaveContext(cur_thread->GetContext32());
cpu_core.SaveContext(cur_thread->GetContext64());
// Save the TPIDR_EL0 system register in case it was modified.
cur_thread->SetTPIDR_EL0(cpu_core.GetTPIDR_EL0());
cpu_core.ClearExclusiveState();
}
// Check if the thread is terminated by checking the DPC flags.
if ((sp.dpc_flags & static_cast<u32>(DpcFlag::Terminated)) == 0) {
// The thread isn't terminated, so we want to unlock it.
sp.m_lock.store(false, std::memory_order_seq_cst);
}
Unload(cur_thread);
// The current thread's context has been entirely taken care of.
// Now we want to loop until we successfully switch the thread context.
@ -411,45 +408,24 @@ void KScheduler::ScheduleImplOffStack() {
// Check if the highest priority thread is null.
if (!highest_priority_thread) {
// The next thread is nullptr!
// Switch to nullptr. This will actually switch to the idle thread.
SwitchThread(nullptr);
// We've switched to the idle thread, so we want to process interrupt tasks until we
// schedule a non-idle thread.
while (!m_state.interrupt_task_runnable) {
// Check if we need scheduling.
if (m_state.needs_scheduling.load(std::memory_order_seq_cst)) {
goto retry;
// Switch to the idle thread. Note: HOS treats idling as a special case for
// performance. This is not *required* for yuzu's purposes, and for singlecore
// compatibility, we can just move the logic that would go here into the execution
// of the idle thread. If we ever remove singlecore, we should implement this
// accurately to HOS.
highest_priority_thread = m_idle_thread;
}
// Clear the previous thread.
m_state.prev_thread = nullptr;
// Wait for an interrupt before checking again.
kernel.System().GetCpuManager().WaitForAndHandleInterrupt();
}
// Execute any pending interrupt tasks.
// m_state.interrupt_task_manager->DoTasks();
// Clear the interrupt task thread as runnable.
m_state.interrupt_task_runnable = false;
// Retry the scheduling loop.
goto retry;
} else {
// We want to try to lock the highest priority thread's context.
// Try to take it.
bool expected{false};
while (!highest_priority_thread->stack_parameters.m_lock.compare_exchange_strong(
expected, true, std::memory_order_seq_cst)) {
while (!highest_priority_thread->context_guard.try_lock()) {
// The highest priority thread's context is already locked.
// Check if we need scheduling. If we don't, we can retry directly.
if (m_state.needs_scheduling.load(std::memory_order_seq_cst)) {
// If we do, another core is interfering, and we must start again.
goto retry;
}
expected = false;
}
// It's time to switch the thread.
@ -461,13 +437,11 @@ void KScheduler::ScheduleImplOffStack() {
if (m_state.needs_scheduling.load(std::memory_order_seq_cst)) {
// Our switch failed.
// We should unlock the thread context, and then retry.
highest_priority_thread->stack_parameters.m_lock.store(false,
std::memory_order_seq_cst);
highest_priority_thread->context_guard.unlock();
goto retry;
} else {
break;
}
}
retry:
@ -480,18 +454,35 @@ void KScheduler::ScheduleImplOffStack() {
}
// Reload the guest thread context.
{
auto& cpu_core = kernel.System().CurrentArmInterface();
cpu_core.LoadContext(highest_priority_thread->GetContext32());
cpu_core.LoadContext(highest_priority_thread->GetContext64());
cpu_core.SetTlsAddress(highest_priority_thread->GetTLSAddress());
cpu_core.SetTPIDR_EL0(highest_priority_thread->GetTPIDR_EL0());
cpu_core.LoadWatchpointArray(highest_priority_thread->GetOwnerProcess()->GetWatchpoints());
cpu_core.ClearExclusiveState();
}
Reload(highest_priority_thread);
// Reload the host thread.
Common::Fiber::YieldTo(m_idle_stack, *highest_priority_thread->host_context);
Common::Fiber::YieldTo(m_switch_fiber, *highest_priority_thread->host_context);
}
void KScheduler::Unload(KThread* thread) {
auto& cpu_core = kernel.System().ArmInterface(m_core_id);
cpu_core.SaveContext(thread->GetContext32());
cpu_core.SaveContext(thread->GetContext64());
// Save the TPIDR_EL0 system register in case it was modified.
thread->SetTPIDR_EL0(cpu_core.GetTPIDR_EL0());
cpu_core.ClearExclusiveState();
// Check if the thread is terminated by checking the DPC flags.
if ((thread->GetStackParameters().dpc_flags & static_cast<u32>(DpcFlag::Terminated)) == 0) {
// The thread isn't terminated, so we want to unlock it.
thread->context_guard.unlock();
}
}
void KScheduler::Reload(KThread* thread) {
auto& cpu_core = kernel.System().ArmInterface(m_core_id);
cpu_core.LoadContext(thread->GetContext32());
cpu_core.LoadContext(thread->GetContext64());
cpu_core.SetTlsAddress(thread->GetTLSAddress());
cpu_core.SetTPIDR_EL0(thread->GetTPIDR_EL0());
cpu_core.LoadWatchpointArray(thread->GetOwnerProcess()->GetWatchpoints());
cpu_core.ClearExclusiveState();
}
void KScheduler::ClearPreviousThread(KernelCore& kernel, KThread* thread) {

View File

@ -41,8 +41,11 @@ public:
explicit KScheduler(KernelCore& kernel);
~KScheduler();
void Initialize(KThread* idle_thread);
void Initialize(KThread* main_thread, KThread* idle_thread, s32 core_id);
void Activate();
void OnThreadStart();
void Unload(KThread* thread);
void Reload(KThread* thread);
void SetInterruptTaskRunnable();
void RequestScheduleOnInterrupt();
@ -55,6 +58,14 @@ public:
return m_idle_thread;
}
bool IsIdle() const {
return m_current_thread.load() == m_idle_thread;
}
std::shared_ptr<Common::Fiber> GetSwitchFiber() {
return m_switch_fiber;
}
KThread* GetPreviousThread() const {
return m_state.prev_thread;
}
@ -69,7 +80,7 @@ public:
// Static public API.
static bool CanSchedule(KernelCore& kernel) {
return kernel.GetCurrentEmuThread()->GetDisableDispatchCount() == 0;
return GetCurrentThread(kernel).GetDisableDispatchCount() == 0;
}
static bool IsSchedulerLockedByCurrentThread(KernelCore& kernel) {
return kernel.GlobalSchedulerContext().scheduler_lock.IsLockedByCurrentThread();
@ -113,7 +124,7 @@ private:
// Instanced private API.
void ScheduleImpl();
void ScheduleImplOffStack();
void ScheduleImplFiber();
void SwitchThread(KThread* next_thread);
void Schedule();
@ -147,9 +158,10 @@ private:
KThread* m_idle_thread{nullptr};
std::atomic<KThread*> m_current_thread{nullptr};
std::shared_ptr<Common::Fiber> m_idle_stack{};
KThread* m_idle_cur_thread{};
KThread* m_idle_highest_priority_thread{};
std::shared_ptr<Common::Fiber> m_switch_fiber{};
KThread* m_switch_cur_thread{};
KThread* m_switch_highest_priority_thread{};
bool m_switch_from_schedule{};
};
class KScopedSchedulerLock : public KScopedLock<KScheduler::LockType> {

View File

@ -268,7 +268,7 @@ Result KThread::InitializeMainThread(Core::System& system, KThread* thread, s32
Result KThread::InitializeIdleThread(Core::System& system, KThread* thread, s32 virt_core) {
return InitializeThread(thread, {}, {}, {}, IdleThreadPriority, virt_core, {}, ThreadType::Main,
abort);
system.GetCpuManager().GetIdleThreadStartFunc());
}
Result KThread::InitializeHighPriorityThread(Core::System& system, KThread* thread,
@ -1204,8 +1204,9 @@ KScopedDisableDispatch::~KScopedDisableDispatch() {
return;
}
// Skip the reschedule if single-core, as dispatch tracking is disabled here.
// Skip the reschedule if single-core.
if (!Settings::values.use_multi_core.GetValue()) {
GetCurrentThread(kernel).EnableDispatch();
return;
}

View File

@ -439,7 +439,6 @@ public:
bool is_pinned;
s32 disable_count;
KThread* cur_thread;
std::atomic<bool> m_lock;
};
[[nodiscard]] StackParameters& GetStackParameters() {
@ -485,39 +484,16 @@ public:
return per_core_priority_queue_entry[core];
}
[[nodiscard]] bool IsKernelThread() const {
return GetActiveCore() == 3;
}
[[nodiscard]] bool IsDispatchTrackingDisabled() const {
return is_single_core || IsKernelThread();
}
[[nodiscard]] s32 GetDisableDispatchCount() const {
if (IsDispatchTrackingDisabled()) {
// TODO(bunnei): Until kernel threads are emulated, we cannot enable/disable dispatch.
return 1;
}
return this->GetStackParameters().disable_count;
}
void DisableDispatch() {
if (IsDispatchTrackingDisabled()) {
// TODO(bunnei): Until kernel threads are emulated, we cannot enable/disable dispatch.
return;
}
ASSERT(GetCurrentThread(kernel).GetDisableDispatchCount() >= 0);
this->GetStackParameters().disable_count++;
}
void EnableDispatch() {
if (IsDispatchTrackingDisabled()) {
// TODO(bunnei): Until kernel threads are emulated, we cannot enable/disable dispatch.
return;
}
ASSERT(GetCurrentThread(kernel).GetDisableDispatchCount() > 0);
this->GetStackParameters().disable_count--;
}

View File

@ -64,8 +64,6 @@ struct KernelCore::Impl {
is_phantom_mode_for_singlecore = false;
InitializePhysicalCores();
// Derive the initial memory layout from the emulated board
Init::InitializeSlabResourceCounts(kernel);
DeriveInitialMemoryLayout();
@ -77,6 +75,7 @@ struct KernelCore::Impl {
Init::InitializeKPageBufferSlabHeap(system);
InitializeShutdownThreads();
InitializePreemption(kernel);
InitializePhysicalCores();
RegisterHostThread();
}
@ -193,8 +192,21 @@ struct KernelCore::Impl {
exclusive_monitor =
Core::MakeExclusiveMonitor(system.Memory(), Core::Hardware::NUM_CPU_CORES);
for (u32 i = 0; i < Core::Hardware::NUM_CPU_CORES; i++) {
const s32 core{static_cast<s32>(i)};
schedulers[i] = std::make_unique<Kernel::KScheduler>(system.Kernel());
cores.emplace_back(i, system, *schedulers[i], interrupts);
auto* main_thread{Kernel::KThread::Create(system.Kernel())};
main_thread->SetName(fmt::format("MainThread:{}", core));
main_thread->SetCurrentCore(core);
ASSERT(Kernel::KThread::InitializeMainThread(system, main_thread, core).IsSuccess());
auto* idle_thread{Kernel::KThread::Create(system.Kernel())};
idle_thread->SetCurrentCore(core);
ASSERT(Kernel::KThread::InitializeIdleThread(system, idle_thread, core).IsSuccess());
schedulers[i]->Initialize(main_thread, idle_thread, core);
}
}
@ -1093,10 +1105,11 @@ void KernelCore::Suspend(bool suspended) {
}
void KernelCore::ShutdownCores() {
KScopedSchedulerLock lk{*this};
for (auto* thread : impl->shutdown_threads) {
void(thread->Run());
}
InterruptAllPhysicalCores();
}
bool KernelCore::IsMulticore() const {

View File

@ -43,6 +43,7 @@ void PhysicalCore::Initialize([[maybe_unused]] bool is_64_bit) {
void PhysicalCore::Run() {
arm_interface->Run();
arm_interface->ClearExclusiveState();
}
void PhysicalCore::Idle() {