CpuManager: simplify pausing

This commit is contained in:
Liam 2022-05-27 20:44:45 -04:00
parent 073714a762
commit af022294dd
3 changed files with 36 additions and 95 deletions

View file

@ -16,7 +16,8 @@
namespace Core { namespace Core {
CpuManager::CpuManager(System& system_) : system{system_} {} CpuManager::CpuManager(System& system_)
: pause_barrier{std::make_unique<Common::Barrier>(1)}, system{system_} {}
CpuManager::~CpuManager() = default; CpuManager::~CpuManager() = default;
void CpuManager::ThreadStart(std::stop_token stop_token, CpuManager& cpu_manager, void CpuManager::ThreadStart(std::stop_token stop_token, CpuManager& cpu_manager,
@ -30,8 +31,10 @@ void CpuManager::Initialize() {
for (std::size_t core = 0; core < Core::Hardware::NUM_CPU_CORES; core++) { for (std::size_t core = 0; core < Core::Hardware::NUM_CPU_CORES; core++) {
core_data[core].host_thread = std::jthread(ThreadStart, std::ref(*this), core); core_data[core].host_thread = std::jthread(ThreadStart, std::ref(*this), core);
} }
pause_barrier = std::make_unique<Common::Barrier>(Core::Hardware::NUM_CPU_CORES + 1);
} else { } else {
core_data[0].host_thread = std::jthread(ThreadStart, std::ref(*this), 0); core_data[0].host_thread = std::jthread(ThreadStart, std::ref(*this), 0);
pause_barrier = std::make_unique<Common::Barrier>(2);
} }
} }
@ -138,51 +141,14 @@ void CpuManager::MultiCoreRunSuspendThread() {
auto core = kernel.CurrentPhysicalCoreIndex(); auto core = kernel.CurrentPhysicalCoreIndex();
auto& scheduler = *kernel.CurrentScheduler(); auto& scheduler = *kernel.CurrentScheduler();
Kernel::KThread* current_thread = scheduler.GetCurrentThread(); Kernel::KThread* current_thread = scheduler.GetCurrentThread();
current_thread->DisableDispatch();
Common::Fiber::YieldTo(current_thread->GetHostContext(), *core_data[core].host_context); Common::Fiber::YieldTo(current_thread->GetHostContext(), *core_data[core].host_context);
ASSERT(scheduler.ContextSwitchPending());
ASSERT(core == kernel.CurrentPhysicalCoreIndex()); ASSERT(core == kernel.CurrentPhysicalCoreIndex());
scheduler.RescheduleCurrentCore(); scheduler.RescheduleCurrentCore();
} }
} }
void CpuManager::MultiCorePause(bool paused) {
if (!paused) {
bool all_not_barrier = false;
while (!all_not_barrier) {
all_not_barrier = true;
for (const auto& data : core_data) {
all_not_barrier &= !data.is_running.load() && data.initialized.load();
}
}
for (auto& data : core_data) {
data.enter_barrier->Set();
}
if (paused_state.load()) {
bool all_barrier = false;
while (!all_barrier) {
all_barrier = true;
for (const auto& data : core_data) {
all_barrier &= data.is_paused.load() && data.initialized.load();
}
}
for (auto& data : core_data) {
data.exit_barrier->Set();
}
}
} else {
/// Wait until all cores are paused.
bool all_barrier = false;
while (!all_barrier) {
all_barrier = true;
for (const auto& data : core_data) {
all_barrier &= data.is_paused.load() && data.initialized.load();
}
}
/// Don't release the barrier
}
paused_state = paused;
}
/////////////////////////////////////////////////////////////////////////////// ///////////////////////////////////////////////////////////////////////////////
/// SingleCore /// /// SingleCore ///
/////////////////////////////////////////////////////////////////////////////// ///////////////////////////////////////////////////////////////////////////////
@ -235,8 +201,9 @@ void CpuManager::SingleCoreRunSuspendThread() {
auto core = kernel.GetCurrentHostThreadID(); auto core = kernel.GetCurrentHostThreadID();
auto& scheduler = *kernel.CurrentScheduler(); auto& scheduler = *kernel.CurrentScheduler();
Kernel::KThread* current_thread = scheduler.GetCurrentThread(); Kernel::KThread* current_thread = scheduler.GetCurrentThread();
current_thread->DisableDispatch();
Common::Fiber::YieldTo(current_thread->GetHostContext(), *core_data[0].host_context); Common::Fiber::YieldTo(current_thread->GetHostContext(), *core_data[0].host_context);
ASSERT(scheduler.ContextSwitchPending());
ASSERT(core == kernel.GetCurrentHostThreadID()); ASSERT(core == kernel.GetCurrentHostThreadID());
scheduler.RescheduleCurrentCore(); scheduler.RescheduleCurrentCore();
} }
@ -274,37 +241,21 @@ void CpuManager::PreemptSingleCore(bool from_running_enviroment) {
} }
} }
void CpuManager::SingleCorePause(bool paused) { void CpuManager::Pause(bool paused) {
if (!paused) { std::scoped_lock lk{pause_lock};
bool all_not_barrier = false;
while (!all_not_barrier) { if (pause_state == paused) {
all_not_barrier = !core_data[0].is_running.load() && core_data[0].initialized.load(); return;
}
core_data[0].enter_barrier->Set();
if (paused_state.load()) {
bool all_barrier = false;
while (!all_barrier) {
all_barrier = core_data[0].is_paused.load() && core_data[0].initialized.load();
}
core_data[0].exit_barrier->Set();
}
} else {
/// Wait until all cores are paused.
bool all_barrier = false;
while (!all_barrier) {
all_barrier = core_data[0].is_paused.load() && core_data[0].initialized.load();
}
/// Don't release the barrier
}
paused_state = paused;
} }
void CpuManager::Pause(bool paused) { // Set the new state
if (is_multicore) { pause_state.store(paused);
MultiCorePause(paused);
} else { // Wake up any waiting threads
SingleCorePause(paused); pause_state.notify_all();
}
// Wait for all threads to successfully change state before returning
pause_barrier->Sync();
} }
void CpuManager::RunThread(std::stop_token stop_token, std::size_t core) { void CpuManager::RunThread(std::stop_token stop_token, std::size_t core) {
@ -320,27 +271,29 @@ void CpuManager::RunThread(std::stop_token stop_token, std::size_t core) {
Common::SetCurrentThreadName(name.c_str()); Common::SetCurrentThreadName(name.c_str());
Common::SetCurrentThreadPriority(Common::ThreadPriority::High); Common::SetCurrentThreadPriority(Common::ThreadPriority::High);
auto& data = core_data[core]; auto& data = core_data[core];
data.enter_barrier = std::make_unique<Common::Event>();
data.exit_barrier = std::make_unique<Common::Event>();
data.host_context = Common::Fiber::ThreadToFiber(); data.host_context = Common::Fiber::ThreadToFiber();
data.is_running = false;
data.initialized = true;
const bool sc_sync = !is_async_gpu && !is_multicore; const bool sc_sync = !is_async_gpu && !is_multicore;
bool sc_sync_first_use = sc_sync; bool sc_sync_first_use = sc_sync;
// Cleanup // Cleanup
SCOPE_EXIT({ SCOPE_EXIT({
data.host_context->Exit(); data.host_context->Exit();
data.enter_barrier.reset();
data.exit_barrier.reset();
data.initialized = false;
MicroProfileOnThreadExit(); MicroProfileOnThreadExit();
}); });
/// Running /// Running
while (running_mode) { while (running_mode) {
data.is_running = false; if (pause_state.load(std::memory_order_relaxed)) {
data.enter_barrier->Wait(); // Wait for caller to acknowledge pausing
pause_barrier->Sync();
// Wait until unpaused
pause_state.wait(true, std::memory_order_relaxed);
// Wait for caller to acknowledge unpausing
pause_barrier->Sync();
}
if (sc_sync_first_use) { if (sc_sync_first_use) {
system.GPU().ObtainContext(); system.GPU().ObtainContext();
sc_sync_first_use = false; sc_sync_first_use = false;
@ -352,12 +305,7 @@ void CpuManager::RunThread(std::stop_token stop_token, std::size_t core) {
} }
auto current_thread = system.Kernel().CurrentScheduler()->GetCurrentThread(); auto current_thread = system.Kernel().CurrentScheduler()->GetCurrentThread();
data.is_running = true;
Common::Fiber::YieldTo(data.host_context, *current_thread->GetHostContext()); Common::Fiber::YieldTo(data.host_context, *current_thread->GetHostContext());
data.is_running = false;
data.is_paused = true;
data.exit_barrier->Wait();
data.is_paused = false;
} }
} }

View file

@ -69,13 +69,11 @@ private:
void MultiCoreRunGuestLoop(); void MultiCoreRunGuestLoop();
void MultiCoreRunIdleThread(); void MultiCoreRunIdleThread();
void MultiCoreRunSuspendThread(); void MultiCoreRunSuspendThread();
void MultiCorePause(bool paused);
void SingleCoreRunGuestThread(); void SingleCoreRunGuestThread();
void SingleCoreRunGuestLoop(); void SingleCoreRunGuestLoop();
void SingleCoreRunIdleThread(); void SingleCoreRunIdleThread();
void SingleCoreRunSuspendThread(); void SingleCoreRunSuspendThread();
void SingleCorePause(bool paused);
static void ThreadStart(std::stop_token stop_token, CpuManager& cpu_manager, std::size_t core); static void ThreadStart(std::stop_token stop_token, CpuManager& cpu_manager, std::size_t core);
@ -83,16 +81,13 @@ private:
struct CoreData { struct CoreData {
std::shared_ptr<Common::Fiber> host_context; std::shared_ptr<Common::Fiber> host_context;
std::unique_ptr<Common::Event> enter_barrier;
std::unique_ptr<Common::Event> exit_barrier;
std::atomic<bool> is_running;
std::atomic<bool> is_paused;
std::atomic<bool> initialized;
std::jthread host_thread; std::jthread host_thread;
}; };
std::atomic<bool> running_mode{}; std::atomic<bool> running_mode{};
std::atomic<bool> paused_state{}; std::atomic<bool> pause_state{};
std::unique_ptr<Common::Barrier> pause_barrier{};
std::mutex pause_lock{};
std::array<CoreData, Core::Hardware::NUM_CPU_CORES> core_data{}; std::array<CoreData, Core::Hardware::NUM_CPU_CORES> core_data{};

View file

@ -252,6 +252,7 @@ struct KernelCore::Impl {
core_id) core_id)
.IsSuccess()); .IsSuccess());
suspend_threads[core_id]->SetName(fmt::format("SuspendThread:{}", core_id)); suspend_threads[core_id]->SetName(fmt::format("SuspendThread:{}", core_id));
suspend_threads[core_id]->DisableDispatch();
} }
} }
@ -1073,9 +1074,6 @@ void KernelCore::Suspend(bool in_suspention) {
impl->suspend_threads[core_id]->SetState(state); impl->suspend_threads[core_id]->SetState(state);
impl->suspend_threads[core_id]->SetWaitReasonForDebugging( impl->suspend_threads[core_id]->SetWaitReasonForDebugging(
ThreadWaitReasonForDebugging::Suspended); ThreadWaitReasonForDebugging::Suspended);
if (!should_suspend) {
impl->suspend_threads[core_id]->DisableDispatch();
}
} }
} }
} }