suyu/src/video_core/host1x/syncpoint_manager.cpp

// Copyright 2021 yuzu Emulator Project
// Licensed under GPLv3 or any later version
// Refer to the license.txt file included.

#include "video_core/host1x/syncpoint_manager.h"

namespace Tegra {

namespace Host1x {

SyncpointManager::ActionHandle SyncpointManager::RegisterAction(
    std::atomic<u32>& syncpoint, std::list<RegisteredAction>& action_storage, u32 expected_value,
    std::function<void(void)>& action) {
    if (syncpoint.load(std::memory_order_acquire) >= expected_value) {
        action();
        return {};
    }

    std::unique_lock<std::mutex> lk(guard);
    if (syncpoint.load(std::memory_order_relaxed) >= expected_value) {
        action();
        return {};
    }
    auto it = action_storage.begin();
    while (it != action_storage.end()) {
        if (it->expected_value >= expected_value) {
            break;
        }
        ++it;
    }
    return action_storage.emplace(it, expected_value, action);
}

void SyncpointManager::DeregisterAction(std::list<RegisteredAction>& action_storage,
                                        ActionHandle& handle) {
    std::unique_lock<std::mutex> lk(guard);
    action_storage.erase(handle);
}

void SyncpointManager::DeregisterGuestAction(u32 syncpoint_id, ActionHandle& handle) {
    DeregisterAction(guest_action_storage[syncpoint_id], handle);
}

void SyncpointManager::DeregisterHostAction(u32 syncpoint_id, ActionHandle& handle) {
    DeregisterAction(host_action_storage[syncpoint_id], handle);
}

void SyncpointManager::IncrementGuest(u32 syncpoint_id) {
    Increment(syncpoints_guest[syncpoint_id], wait_guest_cv, guest_action_storage[syncpoint_id]);
}

void SyncpointManager::IncrementHost(u32 syncpoint_id) {
    Increment(syncpoints_host[syncpoint_id], wait_host_cv, host_action_storage[syncpoint_id]);
}

void SyncpointManager::WaitGuest(u32 syncpoint_id, u32 expected_value) {
    Wait(syncpoints_guest[syncpoint_id], wait_guest_cv, expected_value);
}

void SyncpointManager::WaitHost(u32 syncpoint_id, u32 expected_value) {
    Wait(syncpoints_host[syncpoint_id], wait_host_cv, expected_value);
}

void SyncpointManager::Increment(std::atomic<u32>& syncpoint, std::condition_variable& wait_cv,
                                 std::list<RegisteredAction>& action_storage) {
    auto new_value{syncpoint.fetch_add(1, std::memory_order_acq_rel) + 1};

    std::unique_lock<std::mutex> lk(guard);
    auto it = action_storage.begin();
    while (it != action_storage.end()) {
        if (it->expected_value > new_value) {
            break;
        }
        it->action();
        it = action_storage.erase(it);
    }
    wait_cv.notify_all();
}

void SyncpointManager::Wait(std::atomic<u32>& syncpoint, std::condition_variable& wait_cv,
                            u32 expected_value) {
    const auto pred = [&]() { return syncpoint.load(std::memory_order_acquire) >= expected_value; };
    if (pred()) {
        return;
    }

    std::unique_lock<std::mutex> lk(guard);
    wait_cv.wait(lk, pred);
}

} // namespace Host1x

} // namespace Tegra