video_core: Use a CV for blocking commands.

There is no need for a busy loop here. Let's just use a condition variable to save some power.
This commit is contained in:
Markus Wick 2021-04-07 11:41:31 +02:00
parent e6fb49fa4b
commit e8bd9aed8b
2 changed files with 32 additions and 24 deletions

View file

@ -56,11 +56,17 @@ static void RunThread(Core::System& system, VideoCore::RendererBase& renderer,
} else if (const auto* invalidate = std::get_if<InvalidateRegionCommand>(&next.data)) {
rasterizer->OnCPUWrite(invalidate->addr, invalidate->size);
} else if (std::holds_alternative<EndProcessingCommand>(next.data)) {
return;
ASSERT(state.is_running == false);
} else {
UNREACHABLE();
}
state.signaled_fence.store(next.fence);
if (next.block) {
// We have to lock the write_lock to ensure that the condition_variable wait not get a
// race between the check and the lock itself.
std::lock_guard lk(state.write_lock);
state.cv.notify_all();
}
}
}
@ -105,9 +111,8 @@ void ThreadManager::FlushRegion(VAddr addr, u64 size) {
case Settings::GPUAccuracy::Extreme: {
auto& gpu = system.GPU();
u64 fence = gpu.RequestFlush(addr, size);
PushCommand(GPUTickCommand());
while (fence > gpu.CurrentFlushRequestFence()) {
}
PushCommand(GPUTickCommand(), true);
ASSERT(fence <= gpu.CurrentFlushRequestFence());
break;
}
default:
@ -124,18 +129,16 @@ void ThreadManager::FlushAndInvalidateRegion(VAddr addr, u64 size) {
rasterizer->OnCPUWrite(addr, size);
}
void ThreadManager::WaitIdle() const {
while (state.last_fence > state.signaled_fence.load(std::memory_order_relaxed) &&
state.is_running) {
}
}
void ThreadManager::ShutDown() {
if (!state.is_running) {
return;
}
state.is_running = false;
{
std::lock_guard lk(state.write_lock);
state.is_running = false;
state.cv.notify_all();
}
if (!thread.joinable()) {
return;
@ -150,15 +153,21 @@ void ThreadManager::OnCommandListEnd() {
PushCommand(OnCommandListEndCommand());
}
u64 ThreadManager::PushCommand(CommandData&& command_data) {
std::unique_lock lk(state.write_lock);
const u64 fence{++state.last_fence};
state.queue.Push(CommandDataContainer(std::move(command_data), fence));
u64 ThreadManager::PushCommand(CommandData&& command_data, bool block) {
if (!is_async) {
// In synchronous GPU mode, block the caller until the command has executed
lk.unlock();
WaitIdle();
block = true;
}
std::unique_lock lk(state.write_lock);
const u64 fence{++state.last_fence};
state.queue.Push(CommandDataContainer(std::move(command_data), fence, block));
if (block) {
state.cv.wait(lk, [this, fence] {
return fence <= state.signaled_fence.load(std::memory_order_relaxed) ||
!state.is_running;
});
}
return fence;

View file

@ -90,11 +90,12 @@ using CommandData =
struct CommandDataContainer {
CommandDataContainer() = default;
explicit CommandDataContainer(CommandData&& data_, u64 next_fence_)
: data{std::move(data_)}, fence{next_fence_} {}
explicit CommandDataContainer(CommandData&& data_, u64 next_fence_, bool block_)
: data{std::move(data_)}, fence{next_fence_}, block(block_) {}
CommandData data;
u64 fence{};
bool block{};
};
/// Struct used to synchronize the GPU thread
@ -106,6 +107,7 @@ struct SynchState final {
CommandQueue queue;
u64 last_fence{};
std::atomic<u64> signaled_fence{};
std::condition_variable cv;
};
/// Class used to manage the GPU thread
@ -140,10 +142,7 @@ public:
private:
/// Pushes a command to be executed by the GPU thread
u64 PushCommand(CommandData&& command_data);
// Wait until the gpu thread is idle.
void WaitIdle() const;
u64 PushCommand(CommandData&& command_data, bool block = false);
Core::System& system;
const bool is_async;