Method Schedule

src/task/schedule.cpp:36–132

}

auto TaskManager::Schedule() -> void {
  auto& cpu_sched = GetCurrentCpuSched();
  cpu_sched.lock.Lock().or_else([](auto&& err) {
    klog::Err("Schedule: Failed to acquire lock: {}", err.message());
    while (true) {
      cpu_io::Pause();
    }
    return Expected<void>{};
  });

  cpu_sched.scheduler_started = true;

  auto* current = GetCurrentTask();
  assert(current != nullptr && "Schedule: No current task to schedule");

  // 处理当前任务状态
  if (current->GetStatus() == TaskStatus::kRunning) {
    // 将当前任务标记为就绪并重新入队（如果它还能运行）
    current->fsm.Receive(MsgYield{});
    auto* scheduler =
        cpu_sched.schedulers[static_cast<uint8_t>(current->policy)].get();

    if (scheduler) {
      scheduler->OnPreempted(current);
      // 调度器决定如何处理被抢占的任务
      // 大多数情况下需要重新入队，除非是特殊策略
      if (scheduler->OnTimeSliceExpired(current)) {
        scheduler->Enqueue(current);
      }
    }
  }

  // 选择下一个任务 (按策略优先级: RealTime > Normal > Idle)
  TaskControlBlock* next = nullptr;
  for (auto& scheduler : cpu_sched.schedulers) {
    if (scheduler && !scheduler->IsEmpty()) {
      next = scheduler->PickNext();
      if (next) {
        break;
      }
    }
  }

  // 如果没有任务可运行
  if (!next) {
    // 如果当前任务仍然可以运行，继续运行它
    if (current->GetStatus() == TaskStatus::kReady) {
      next = current;
    } else {
      // 否则统计空闲时间并返回
      cpu_sched.idle_time++;
      cpu_sched.lock.UnLock().or_else([](auto&& err) {
        klog::Err("Schedule: Failed to release lock: {}", err.message());
        while (true) {
          cpu_io::Pause();
        }
        return Expected<void>{};
      });